Fresh light shed on mystery of infant consciousness

October 12, 2023

Science Daily/Trinity College Dublin

There is evidence that some form of conscious experience is present by birth, and perhaps even in late pregnancy, an international team of researchers from Trinity College Dublin and colleagues in Australia, Germany and the USA has found.

The findings, published today in the peer-reviewed journal Trends in Cognitive Science, have important clinical, ethical and potentially legal implications, according to the authors.

In the study, entitled 'Consciousness in the cradle: on the emergence of infant experience', the researchers argue that by birth the infant's developing brain is capable of conscious experiences that can make a lasting imprint on their developing sense of self and understanding of their environment.

The team comprised neuroscientists and philosophers from Monash University, in Australia, University of Tübingen, in Germany, University of Minnesota, in the USA, and Trinity College Dublin.

Although each of us was once a baby, infant consciousness remains mysterious, because infants cannot tell us what they think or feel, explains one of the two lead authors of the paper Dr Tim Bayne, Professor of Philosophy at Monash University (Melbourne).

"Nearly everyone who has held a newborn infant has wondered what, if anything, it is like to be a baby. But of course we cannot remember our infancy, and consciousness researchers have disagreed on whether consciousness arises 'early' (at birth or shortly after) or 'late' - by one year of age, or even much later."

To provide a new perspective on when consciousness first emerges, the team built upon recent advances in consciousness science. In adults, some markers from brain imaging have been found to reliably differentiate consciousness from its absence, and are increasingly applied in science and medicine. This is the first time that a review of these markers in infants has been used to assess their consciousness.

Co-author of the study, Lorina Naci, Associate Professor in the School of Psychology, who leads Trinity's 'Consciousness and Cognition Group, explained: "Our findings suggest that newborns can integrate sensory and developing cognitive responses into coherent conscious experiences to understand the actions of others and plan their own responses."

The paper also sheds light into 'what it is like' to be a baby. We know that seeing is much more immature in babies than hearing, for example. Furthermore, this work suggests that, at any point in time, infants are aware of fewer items than adults, and can take longer to grasp what's in front of them, but they can easily process more diverse information, such as sounds from other languages, than their older selves.

https://www.sciencedaily.com/releases/2023/10/231012161754.htm

No universal body image experience in pregnancy

New meta-analysis finds large differences in people's body image dissatisfaction

October 12, 2023

Science Daily/Anglia Ruskin University

A new study has discovered large variations in how pregnancy can affect women's perceptions of their own body, including experiences of negative body image.

Negative body image during pregnancy is known to have serious adverse effects on both the mother and baby. Overall, average levels of body image dissatisfaction were found to be similar for pregnant women compared to the general female population, but the research discovered large differences -- both positive and negative -- on an individual basis.

The study, published in the journal BMC Pregnancy and Childbirth, is thought to be the first meta-analysis comparing the two groups of women, and was led by academics from Anglia Ruskin University (ARU) and the University of York.

The researchers initially screened 2,017 separate academic studies, before focusing on 17 studies that provided comparable data. In total, the research included 5,200 responses from women who were pregnant and 4,172 responses from women who were not pregnant.

By synthesising results from multiple studies, the new research found women's body image dissatisfaction overall was not statistically different during pregnancy compared with when not pregnant. However, when looking at the separate studies that formed part of the meta-analysis, there are significant variations on an individual level.

The researchers believe that body image dissatisfaction in pregnancy is made up of a combination of complex factors related to the experiences of each woman -- some positive, some negative.

For some women, body image satisfaction will worsen during pregnancy because of "feeling fat," while others describe feeling that their body is out of their control because they are aware their body will change but cannot stop it. Unrealistic portrayals of pregnant women in the media, often edited to remove uneven skin tone and stretch marks, are also believed to contribute to body image dissatisfaction.

However other pregnant women report having improved body positivity compared to when not pregnant, as they no longer compare their body to the "thin ideal" body type. Some say the improvement is because they place less attention on how their body looks and more on its functionality, focusing on the fetus' health and their maternal role.

Understanding the causes of body image dissatisfaction in pregnant women is important because it can have a serious effect on the mental and physical health of both mother and baby. Many women who display body image dissatisfaction during pregnancy also exhibit depression and anxiety, both postnatally and longer term. This can lead to negative emotional, cognitive, and behavioural outcomes for the child, as well as poor quality mother-infant interactions.

In addition, body image dissatisfaction has been linked with physical illness as the expectant mother may engage in practices such as unhealthy eating, dieting, purging, and fasting. This can have unwanted negative effects on the fetus, such as low birth weight and premature birth.

Lead author Anna Crossland, University of York, said: "Due to the impact that body dissatisfaction can have on the expectant mother and fetus, it is vital to understand how body image dissatisfaction may change on an individual basis when women are pregnant. What our study has found is there is no universal experience during pregnancy, and so we shouldn't assume how people feel. Pressures about how we look are still felt by some people during pregnancy and it is much more helpful to ask how someone is, rather than commenting on their appearance."

Co-author Dr Elizabeth Kirk, Senior Lecturer in Psychology at Anglia Ruskin University, said: "Our earlier work found that women who didn't feel good about their changing bodies in pregnancy reported lower feelings of bonding with their unborn baby. Therefore, it is crucial that we better understand and support women's body image during pregnancy, to help women on an individual basis."

https://www.sciencedaily.com/releases/2023/10/231012161748.htm

Young children who are close to their parents are more likely to grow up kind, helpful and 'prosocial'

October 9, 2023

Science Daily/University of Cambridge

A loving bond between parents and their children early in life significantly increases the child's tendency to be 'prosocial', and act with kindness and empathy towards others, research indicates.

The University of Cambridge study used data from more than 10,000 people born between 2000 and 2002 to understand the long-term interplay between our early relationships with our parents, prosociality and mental health. It is one of the first studies to look at how these characteristics interact over a long period spanning childhood and adolescence.

The researchers found that people who experienced warm and loving relationships with their parents at age three not only tended to have fewer mental health problems during early childhood and adolescence, but also displayed heightened 'prosocial' tendencies. This refers to socially-desirable behaviours intended to benefit others, such as kindness, empathy, helpfulness, generosity and volunteering.

Although the correlation between parent-child relationships and later prosociality needs to be verified through further research, the study points to a sizeable association. On average, it found that for every standard unit above 'normal' levels that a child's closeness with their parents was higher at age three, their prosociality increased by 0.24 of a standard unit by adolescence.

Conversely, children whose early parental relationships were emotionally strained or abusive were less likely to develop prosocial habits over time. The researchers suggest this strengthens the case for developing targeted policies and support for young families within which establishing close parent-child relationships may not always be straightforward; for example, if parents are struggling with financial and work pressures and do not have much time.

The study also explored how far mental health and prosocial behaviour are fixed 'traits' in young people, and how far they fluctuate according to circumstances like changes at school or in personal relationships. It measured both mental health and prosociality at ages five, seven, 11, 14 and 17 in order to develop a comprehensive picture of the dynamics shaping these characteristics and how they interact.

https://www.sciencedaily.com/releases/2023/10/231009191705.htm

Brain is 'rewired' during pregnancy to prepare for motherhood

October 5, 2023

Science Daily/The Francis Crick Institute

Researchers at the Francis Crick Institute have shown that pregnancy hormones 'rewire' the brain to prepare mice for motherhood.

Their findings, published today in Science, show that both estrogen and progesterone act on a small population of neurons in the brain to switch on parental behaviour even before offspring arrive. These adaptations resulted in stronger and more selective responses to pups.

It is well known that while virgin female rodents do not show much interaction with pups, mothers spend most of their time looking after young. It was thought that hormones released when giving birth are most crucial for this onset of maternal behaviour.

But earlier research also showed that rats who have given birth by Caesarean section, and virgin mice exposed to pregnancy hormones, still display this maternal behaviour, suggesting that hormone changes already during pregnancy may be more important.

In the current study, the researchers found that female mice indeed showed increased parental behaviour during late pregnancy, and that exposure to pups wasn't necessary for this change in behaviour.

They found that a population of nerve cells (galanin-expressing neurons) in an area of the brain called the medial preoptic area (MPOA) in the hypothalamus, associated with parenting, was impacted by estrogen and progesterone.

Brain recordings showed that estrogen simultaneously reduced the baseline activity of these neurons and made them more excitable, whereas progesterone rewired their inputs, by recruiting more synapses (sites of communication between neurons).

Making these neurons insensitive to hormones completely removed the onset of parental behaviour during pregnancy. Mice failed to show parental behaviour even after giving birth, suggesting there is a critical period during pregnancy when these hormones take effect.

While some of these changes lasted for at least a month after giving birth, others seem to be permanent, suggesting pregnancy can lead to long-term rewiring of the female brain.

Jonny Kohl, Group Leader of the State-Dependent Neural Processing Laboratory at the Crick, said: "We know that the female body changes during pregnancy to prepare for bringing up young. One example is the production of milk, which starts long before giving birth. Our research shows that such preparations are taking place in the brain, too.

"We think that these changes, often referred to as 'baby brain', cause a change in priority -- virgin mice focus on mating, so don't need to respond to other females' pups, whereas mothers need to perform robust parental behaviour to ensure pup survival. What's fascinating is that this switch doesn't happen at birth -- the brain is preparing much earlier for this big life change."

Rachida Ammari, postdoctoral fellow at the Crick, and first author along with PhD student Francesco Monaca, said: "We've demonstrated that there's a window of plasticity in the brain to prepare for future behavioural challenges. These neurons receive a large number of inputs from elsewhere in the brain, so now we're hoping to understand where this new information comes from."

The researchers believe the brain may also be rewired in a similar way during pregnancy in humans, as the same hormonal changes are expected to impact the same areas of the brain. This could influence parental behaviour alongside environmental and social cues.

https://www.sciencedaily.com/releases/2023/10/231005161752.htm

Should fathers be screened for postpartum depression?

October 4, 2023

Science Daily/University of Illinois Chicago

Dads can suffer from postpartum depression, and a new pilot study at the University of Illinois Chicago suggests they can and should be screened for the condition. Given the intertwined effects of mothers' and fathers' physical and mental health, addressing the health of fathers may be a powerful untapped tool in improving the nation's ongoing maternal health crisis.

The researchers got mothers' permission to interview and screen 24 dads, 30% of whom screened positive for postpartum depression on the same tool that is commonly used to screen moms. Lead author Dr. Sam Wainwright said this points to the importance of asking new dads how they're doing.

"A lot of dads are stressed. They're scared. They're struggling with balancing work and parental and partner responsibilities," he said. "Men are often not doing well, but no one is asking them about it."

Talking to new dads about their mental health takes on additional importance when considering how it can impact their partners' health.

"A woman at risk for postpartum depression is much more likely to get postpartum depression if she has a depressed partner," said Wainwright, assistant professor of internal medicine and pediatrics.

Other studies have estimated that 8% to 13% of new fathers have postpartum depression. Wainwright suspects this study's rate was higher because nearly 90% of the participants identified as being from a racial or ethnic group that faces issues of structural racism and social determinants that can worsen mental health.

The study, published in the journal BMC Pregnancy and Childbirth, was conducted at UI Health's Two-Generation Clinic. Opened in 2020, the clinic grew out of the understanding that new mothers, especially low-resource mothers of color who are taking on parenthood alongside a host of structural challenges often do not prioritize their own health care. However, they are often very diligent in bringing their children to the doctor, Wainwright explained. The Two-Generation Clinic capitalizes on children's visits by offering moms primary care at the same time.

Yet, dads were often left out of this process. Members of the clinic team began chatting with dads to see how they were doing. Wainwright said they'd often hear comments such as, "I'm really stressed, but I don't want my partner to know because I'm here to support her." This study grew out of those conversations.

Those conversations also spurred a larger research project that Wainwright has begun to learn more about the experiences of dads, especially as related to their mental and physical health. Perhaps well-baby visits aren't the only place to reach dads, he said, so he's started talking to fathers-to-be in the obstetrics waiting area, too. He's also asking to screen dads for conditions like high blood pressure during these conversations.

The medical world struggles to connect with young men, who often aren't eager to see a doctor, Wainwright said, so reaching them as they enter fatherhood presents an important opportunity. In fact, some of the men in the postpartum depression study who did not have a primary care physician are now seeing Wainwright for medical care, and others requested mental health services.

The overarching goal of this line of research is to better understand how to help men stay healthy so that their relationships and families are healthy, too, Wainwright explained.

"How can we show them that it's important to take care of yourself for the sake of your baby, for the sake of your partner and for your own sake?" he said.

https://www.sciencedaily.com/releases/2023/10/231004105219.htm

Women living in more walkable neighborhoods have lower rates of obesity-related cancers

October 4, 2023

Science Daily/Columbia University's Mailman School of Public Health

Residing in a more walkable neighborhood protects against the risk of overall obesity-related cancers in women, specifically postmenopausal breast cancer, but also ovarian cancer, endometrial cancer, and multiple myeloma, according to a new study by Columbia University Mailman School of Public Health and NYU Grossman School of Medicine. Obesity has been linked to increased risk for 13 types of cancer in women, and physical activity, independent of body size, lowers risk for some of these cancers. Neighborhood walkability is a set of urban design features that promotes pedestrian activity, supports overall physical activity and is associated with lower body mass index. However, until now long-term studies of neighborhood walkability and risk for obesity-related cancer were limited. The findings are published in the journal Environmental Health Perspectives.

Women who resided in neighborhoods with higher walkability levels, as measured by average destination accessibility and population density over approximately 24 years of follow-up, had lower risk of obesity-related cancers, particularly postmenopausal breast cancer. However, moderate protective associations were also found for endometrial cancer, ovarian cancer, and multiple myeloma. Women in who had lived in areas with the highest levels of neighborhood walkability (the top 25 percent of walkability) had a 26 percent lower risk of obesity-related cancers compared to those who lived in neighborhoods in the lowest 25th percent of walkability.

"These results contribute to the growing evidence of how urban design affects the health and wellbeing in aging populations," said Andrew Rundle, DrPH, professor of epidemiology at Columbia Mailman School. Individual-level interventions to increase physical activity and reduce obesity are costly and often have only short-term effects, according to Rundle and colleagues. "However, urban design can create a context that promotes walking, increases overall physical activity, and reduce car-dependency, which could lead to subsequent improvements in preventing diseases attributed to unhealthy weight," Rundle observed.

"We further observed that the association between high neighborhood walkability and lower risk of overall obesity-related cancers was stronger for women living in neighborhoods with higher levels of poverty" said Sandra India-Aldana, Ph.D., Icahn School of Medicine at Mount Sinai, and lead author. "These findings suggest that neighborhood social and economic environments are also relevant to risk of developing obesity-related cancers."

The researchers studied 14,274 women between the ages of 34 and 65 and recruited at a mammography screening center in NYC between 1985 and 1991 and followed them over nearly three decades. They measured neighborhood walkability in the participant's residential Census-tract throughout follow-up and assessed the association between neighborhood walkability and risk of overall and site-specific obesity-related cancers including postmenopausal breast cancer, ovarian cancer, endometrial cancer, and multiple myeloma. Of the total number of women studied, 18% had a first obesity-related cancer by the end of 2016.The most common cancer was postmenopausal breast cancer at 53%, followed by colorectal cancer at 14%, and endometrial cancer at 12%.

"Our study is unique in that the long-term follow-up allowed us to study effects of walkability with potential long latency periods of cancer and we were able to measure neighborhood walkability as the participants moved residences around the country during follow-up" said co-author Yu Chen Ph.D., NYU Grossman School of Medicine.

https://www.sciencedaily.com/releases/2023/10/231004105202.htm

Job loss is linked to increased risk of miscarriage and stillbirth

September 28, 2023

Science Daily/European Society of Human Reproduction and Embryology

Researchers have found a link between a pregnant woman or her partner losing their job and an increased risk of miscarriage or stillbirth.

The study, which is published today (Thursday) in Human Reproduction, one of the world's leading reproductive medicine journals, found a doubling in the chances of a pregnancy miscarrying or resulting in a stillbirth following a job loss.

The researchers, led by Dr Selin Köksal from the Institute for Social and Economic Research at the University of Essex, UK, emphasise that their findings highlight an association between job loss and an increased probability of miscarriage or stillbirth and that the study cannot show that losing a job causes the pregnancy loss.

"Further research would need to be carried out to understand if losing one's job actually causes the increased risk of pregnancy loss," she said. "I would like to analyse socioeconomic factors influencing pregnancy loss in contexts where data for the entire population are available through administrative records. These data can help clarify whether there are solid causal links between job loss and pregnancy loss, and whether there are certain socioeconomic groups in the population that are particularly at risk, such as economically precarious employees.

"Being able to examine the association between job loss and pregnancy loss among different socioeconomic groups could help us to understand how exactly a job loss is related to higher risk of a miscarriage or a stillbirth. Is it because of economic hardship, or an experience of an unexpected event or is it due to loss of social status? These are the questions that I am hoping to answer in the future."

The study is based on data from the "Understanding Society" survey of 40,000 households in the UK between 2009 and 2022. It includes 8142 pregnancies for which there was complete information on the date of conception and pregnancy outcome.

Out of these pregnancies, 11.6% miscarried (947), which may be an underestimate because many pregnancies do not survive beyond the first month and pregnancy loss can go undetected. There were 38 stillbirths, representing 0.5% of conceptions, which is in line with the UK's official statistics for stillbirths.

Out of 136 women who were affected by their own or their partner's job loss, 32 (23.5%) miscarried and one (0.7%) had a still birth. Among 8006 women who were not affected by their own or their partner's job loss, 915 (10.4%) miscarried and 37 (0.5%) had a stillbirth.

Co-author of the paper, Dr Alessandro Di Nallo, from the Dondena Centre for Research on Social Dynamics and Public Policy at Bocconi University, Milan, Italy, said: "The reasons for these associations may be related to stress, reduced access to prenatal care, or changes in lifestyle.

"My previous research indicates that job loss reduces the likelihood of having children. This might be because people postpone their plans to have children under conditions of economic uncertainty, but it could also be due to other reasons. Stress results in a physiological response, releasing hormones that are known to increase the risk of miscarriage or premature delivery. The reduction in income following a job loss could restrict access and compliance with prenatal care, so that at-risk pregnancies are discovered late or are undetected. In addition, the emotional discomfort of job loss could prompt unhealthy behaviours, such as alcohol consumption, smoking or unhealthy eating."

Dr Köksal said: "Our findings are important as we uncover a potential socioeconomic, hence preventable, factor behind pregnancy losses that can be addressed through effective policymaking.

"It is important to raise awareness of women's legal rights and protection in the workplace during pregnancy, so that women can feel safer and more empowered to communicate their pregnancy with their employer. Moreover, stress during pregnancy can have negative effects on both maternal and foetal health. So, provision of psychological support during pregnancy through the public health system is important regardless of women's and their partner's job status.

"In the UK, pregnancy is a period that is protected fairly well by labour market legislation. However, there is no job loss protection for the partners of pregnant women who are dismissed without notice.Policymakers, for instance, could consider extending job protection to workers whose partners are pregnant as our results shows that a partner's job stability is equally as important as the woman's job stability for the course of pregnancy. Additionally, it makes sense to increase economic support for individuals -- and their partners -- who lose their jobs because the lack of economic support is shown to be one of the main causes of stress and personal distress, which can eventually increase the risk of pregnancy loss."

Limitations of the study include the fact that pregnancy and job loss were self-reported and may be affected by recall and a bias towards what is socially desirable; other factors might also be correlated with both job loss and pregnancy loss; and finally the researchers do not know if the findings hold true for different socioeconomic groups.

"The UK welfare state has an anti-poverty focus and unemployment benefits are less generous than in the rest of Europe -- on average only 34% of the last job's salary for six months. Therefore, it would be interesting to see if more generous welfare regimes are better at reducing the psychosocial hardship of job loss," concluded Dr Köksal.

https://www.sciencedaily.com/releases/2023/09/230928152436.htm

Grandparent childcare may not help the wellbeing of mums or reduce mother-child conflict

September 28, 2023

Science Daily/University of Exeter

Grandparent childcare for toddlers doesn't have an impact on the wellbeing of their mothers, a new study suggests.

Extra help from another generation alone doesn't help mother- child closeness or reduce mother-child conflict, researchers have found.

Researchers who examined information from a sample of mothers could find no statistical link between their children spending time with grandparents at age three and better social and emotional development when they were seven, or better maternal wellbeing and mother-child relationship at age three.

The academics have called for more investment in child and maternal mental health and wellbeing in early childhood. Parents who took part in the study indicated grandparents were their primary source of childcare, and they had less other support.

The study was carried out by Nevra Atış Akyol, from Sivas Cumhuriyet University, Turkey, Derya Atalan Ergin, from Cappadocia University, Turkey, and Angeliki Kallitsoglou, from the University of Exeter.

The researchers examined information from 1,495 mothers and their children. The findings showed that time spent in the care of grandparents for at least six months was not significantly associated with better maternal mental health and wellbeing and mother-child relationship, or better social and emotional outcomes for children when they were seven.

The study, which used data from the Millennium Cohort Study, shows poor maternal wellbeing at age three predicted poor child social and emotional outcomes at age seven.

A total of 39.3 per cent of the children (587), spent between 1 to 10 hours with their grandparents, 33.7 per cent, (505) spent between 11 and 20 hours, and 27 per cent, (403), spent above 21 hours.The Kessler Screening Scale for Psychological Distress was used to assess maternal psychological wellbeing. The 15-item Child Parent Relationship Scale was used to measure maternal perceptions of mother-child relationship. The parent report of the 25- item Strengths and Difficulties Questionnaire was used to assess child ratings of emotional or behavioural difficulties.

"Poor maternal well-being was linked directly with more mother -- child conflict and less mother-child closeness. Poor maternal wellbeing was associated with higher level of emotional problems, conduct problems and peer problems at age seven. Both mother-child conflict and mother-child closeness were linked directly with child social and emotional difficulties when they were seven.

More mother-child conflict at age three was associated with fewer prosocial behaviours and higher levels of inattention/hyperactivity, emotional problems, peer problems and conduct problems at age seen. Lower mother-child closeness at age three was associated with fewer prosocial behaviours, and higher inattention/hyperactivity, emotional problems, peer problems, and conduct problems at age seven.

Dr Kallitsoglou said: "Our findings suggest that there is no direct relationship between maternal psychological wellbeing and the quantity of support provided to families which rely primarily on grandparental childcare arrangements.''

"While an extra pair of hands may impact maternal outcomes such as stress with child upbringing it may not potentially be enough to alleviate more distal parenting outcomes such as maternal psychological distress.''

"However, the findings are tentative. Grandparental support in the form of childcare may have different implications for maternal mental health for families who may have access to fewer resources of support, for instance, single mothers or across different ethnic groups or mothers in full time employment. So, we cannot rule out the possibility the help of grandparents for mothers with characteristics different to those in our sample to have a different impact.''

"We did not find any evidence to suggest that practical support with childcare as measured by the time children spent time in the care of grandparents during the week is beneficial for the parent-child relationship."

https://www.sciencedaily.com/releases/2023/09/230928151119.htm

Is a longer reproductive lifespan good for your brain?

September 28, 2023

Science Daily/American Academy of Neurology

People with a higher cumulative estrogen exposure throughout their life may have a lower risk of cerebral small vessel disease, according to a new study published in the September 27, 2023, online issue of Neurology®, the medical journal of the American Academy of Neurology.

Cerebral small vessel disease, a form of cerebrovascular disease, results from damage to small blood vessels in the brain. It raises the risk of cognitive impairment and dementia.

"Previous research has shown that rates of cerebrovascular disease increase after menopause, which is often attributed to the absence of hormones," said study author Kevin Whittingstall, PhD, of the University of Sherbrooke in Quebec, Canada. "It remains unknown whether the amount of exposure to hormones before menopause extends that window of protection to after menopause."

Researchers looked at the relationship between lifetime hormone exposure, or the number of times a person has been pregnant and their reproductive lifespan, and white matter hyperintensities, a common biomarker of vascular brain health that develops with age.

The study involved 9,000 postmenopausal female participants with an average age of 64 living in the United Kingdom. They did not have cerebral small vessel disease at the start of the study.

Participants answered questions on reproductive health information, including age at first menstruation and start of menopause, number of pregnancies, oral contraceptive use and hormone therapy.

Participants also had brain scans to look for cerebral small vessel disease by estimating white matter hyperintensities, which indicate injury to the brain's white matter.

Researchers calculated lifetime hormone exposure by adding up the number of years participants were pregnant with the duration of their reproductive lifespan, which is the number of years from first menstruation to menopause. The average lifetime hormone exposure was 40 years.

After adjusting for factors like age, high blood pressure, and smoking, researchers found that participants with higher lifetime hormone exposure had lower white matter hyperintensity volumes. Average total white matter hyperintensity volume was 0.0019 milliliters (ml). They found that people with higher lifetime hormone exposure had a smaller volume of white matter hyperintensities, with a difference of 0.007 ml compared to people with lower lifetime hormone exposure.

Researchers also calculated the lifetime hormone exposure by adding up the number of years participants took oral contraceptives and hormone replacement therapy. These factors did not alter the effect the number of pregnancies and number of reproductive years had on white matter hyperintensities.

The number of pregnancies participants had and their number of reproductive years both affected white matter hyperintensity volumes independently

"Our study highlights the critical role of reproductive history in shaping the female brain across the lifetime," said Whittingstall. "These results emphasize the need to integrate reproductive history into managing brain health in postmenopausal women. Future research should investigate ways to develop better hormonal therapies."

A limitation of the study was that information on reproductive factors was collected mainly based on participants' ability to recall events, and participants may not have remembered such events correctly.

The study does not prove that lower estrogen exposure causes cerebral small vessel disease; it only shows an association.

https://www.sciencedaily.com/releases/2023/09/230928152643.htm

Risk of premature birth from smoking while pregnant more than double previous estimates

September 28, 2023

Science Daily/University of Cambridge

Cambridge researchers have found that women who smoke during pregnancy are 2.6 times more likely to give birth prematurely compared to non-smokers -- more than double the previous estimate.

The study, published today in the International Journal of Epidemiology, also found that smoking meant that the baby was four times more likely to be small for its gestational age, putting it at risk of potentially serious complications including breathing difficulties and infections.

But the team found no evidence that caffeine intake was linked to adverse outcomes.

Women are currently recommended to stop smoking and limit their caffeine intake during pregnancy because of the risk of complications to the baby. For example, smoking during pregnancy is associated with an increased risk of fetal growth restriction, premature birth and low birthweight, though it has also been linked to a reduced risk of preeclampsia (high blood pressure during pregnancy).

High caffeine intake has also been shown to be associated with lower birthweights and possibly fetal growth restriction. Caffeine is more difficult to avoid than cigarette smoke as is found in coffee, tea, chocolate, energy drinks, soft drinks, and certain medications.

Studies looking at the links between smoking, caffeine and adverse pregnancy outcomes tend to rely on self-reported data to estimate exposure, which is not always reliable. A more objective measure is to look at levels of metabolites in the blood -- chemical by-products created when substances such as tobacco and caffeine are processed in the body.

Researchers at the University of Cambridge and the Rosie Hospital, part of Cambridge University Hospitals NHS Foundation Trust, recruited more than 4,200 women who attended the hospital between 2008 and 2012 as part of the Pregnancy Outcome Prediction (POP) study. The team analysed blood samples taken from a subset of these women four times during their pregnancies.

To assess exposure to cigarette smoke, the team looked at levels of the metabolite cotinine, which can be detected in blood, urine, and saliva. Only two out of three women with detectable levels of cotinine in every blood sample were self-reported smokers, showing that this measure is a more objective way of assessing smoking behaviour.

A total of 914 women were included in the smoking analysis. Of these, 78.6% were classified as having no exposure to smoking while pregnant, 11.7% as having some exposure and 9.7% as having consistent exposure.

Compared to women who were not exposed to smoking while pregnant, those with consistent exposure were 2.6 times more likely to experience spontaneous preterm birth -- more than double the previous estimate of 1.27 from a meta-analysis of studies -- and 4.1 times as likely to experience fetal growth restriction.

Babies born to smokers were found to be on average 387g lighter than babies born to non-smokers -- that is, more than 10% smaller than the weight of an average newborn. This increases the risk that the baby will have a low birth weight (2.5kg or less), which in turn is linked to an increased risk of developmental problems as well as poorer health in later life.

Unlike in previous studies, however, the team found no evidence that smoking reduced the risk of pre-eclampsia.

Professor Gordon Smith, Head of the Department of Obstetrics and Gynaecology at the University of Cambridge, said: "We've known for a long time that smoking during pregnancy is not good for the baby, but our study shows that it's potentially much worse than previously thought. It puts the baby at risk of potentially serious complications from growing too slowly in the womb or from being born too soon.

"We hope this knowledge will help encourage pregnant mums and women planning pregnancy to access smoking-cessation services. Pregnancy is a key time when women quit and if they can remain tobacco free after the birth there are lifelong benefits for them and their child."

Smoking cessation is offered routinely to all pregnant women and the NHS has local smoking cessation services for anyone, pregnant or not. Further information is available on the NHS website (https://www.nhs.uk/live-well/quit-smoking/nhs-stop-smoking-services-help-you-quit/).

To assess caffeine intake, the researchers looked for the metabolite paraxanthine, which accounts for 80% of caffeine metabolism and is both less sensitive to recent intake and more stable throughout the day.

915 women were included in the caffeine analysis. Of these women, 12.8% had low levels of paraxanthine throughout pregnancy (suggesting low caffeine intake), 74.0% had moderate levels and 13.2% had high levels. There was little evidence of an association between caffeine intake and any of the adverse outcomes.

https://www.sciencedaily.com/releases/2023/09/230928152456.htm

Wearable device data reveals that reduced sleep and activity in pregnancy is linked to premature birth risk

September 28, 2023

Science Daily/Stanford Medicine

A lack of sleep and reduced physical activity during pregnancy are linked to risk of preterm birth, according to new research led by the Stanford School of Medicine.

In the study, which will publish online Sept. 28 in npj Digital Medicine, the researchers collected data from devices worn by more than 1,000 women throughout pregnancy. With a machine learning algorithm, the scientists sifted through participants' activity information to detect fine-grained changes in sleep and physical activity patterns.

"We showed that an artificial intelligence algorithm can build a 'clock' of physical activity and sleep during pregnancy, and can tell how far along a patient's pregnancy is," said senior study author Nima Aghaeepour, PhD, an associate professor of anesthesiology, perioperative and pain medicine and of pediatrics at Stanford Medicine. Normal pregnancy is characterized by progressive changes in sleep and physical activity as the pregnancy advances, he said. "But some patients don't follow that clock." When patients' sleep and activity levels don't change on a typical trajectory, the study showed, it',s a warning sign for premature birth, he added.

The study's lead author is Neal Ravindra, PhD, a former postdoctoral scholar at Stanford Medicine.

As the pregnancies progressed, sleep typically became more disrupted, and women became less physically active, the study showed. However, some women's sleep and activity patterns changed on an accelerated timeline relative to how far along they were in their pregnancies. These individuals were more likely to deliver early, the study found.

"The people who look 'very pregnant' to the AI algorithm -- but are not -- end up being at significantly increased risk of preterm birth," Aghaeepour said.

A struggle to prevent early deliveries

Premature birth, when a baby is born 3 or more weeks early, affects 10.5% of births in the United States; these rates are higher in some other parts of the world. Premature newborns can suffer many medical complications, including diseases of the eyes, lungs, brain and digestive system. Prematurity is the leading cause of death for children under age 5 around the world.

Research has identified a variety of risk factors for premature delivery, including greater levels of inflammation in the pregnant person, specific immune-system changes, African American race, higher levels of stress, history of having a preterm birth and certain types of bacteria in the mother's microbiome.

But doctors still can't reliably determine which pregnancies are at risk for premature delivery. Even when they know a mom is at risk -- because she's previously had a premature delivery, for example -- they still don't have great treatments to extend the pregnancy closer to the due date. Developing medications that could do this would be complex, in part because of ethical concerns regarding testing drugs that might harm the fetus.

If researchers can identify sleep and activity patterns that lower prematurity risk, they can design interventions to help expectant mothers adopt better sleep and exercise habits, a potentially low-risk way of reducing preterm births, Aghaeepour said.

Focusing on at-risk moms

The Stanford Medicine team collaborated with scientists at Washington University in St. Louis, who collected the sleep and physical activity data from 1,083 pregnant women treated there. More than half of the cohort (706 participants) were Black. In the United States, the rate of premature birth is about 50% higher in Black women than in white women.

"Our patient population experiences a lot of adversity, and our preterm birth rates are much higher than at Stanford," said study coauthor Sarah England, PhD, professor of obstetrics and gynecology at Washington University School of Medicine in St. Louis. The study participants included women experiencing a variety of stressors linked with higher rates of preterm birth, such as racism, low socioeconomic status and living in areas with higher crime rates, England said, adding that it is important for studies of preterm birth to include populations with the greatest need. "Typically, Black women and women of color have not been included in many large cohort studies," she said.

The participants wore actigraphy devices similar to smartwatches to collect once-a-minute measurements of physical activity and light exposure starting in the first trimester of pregnancy and continuing until their babies were born. The researchers also had data from participants' electronic medical records on gestational age, or how far along each pregnancy was; maternal medical conditions such as high blood pressure, diabetes, heart disease and depression; pregnancy complications such as preeclampsia and infections; and information about the birth, including duration of the pregnancy, the baby's birth weight and newborn medical complications.

With the movement and light exposure data, the research team developed a machine learning model of activity and sleep during pregnancy. The model shows that patterns of sleep and physical activity change over the course of pregnancy, which generally is associated with more sleep disruption and less physical activity as pregnancy progresses.

"Anecdotally, lots of women will say, 'Of course!'" said study coauthor Erik Herzog, PhD, professor of biology at Washington University in St. Louis, adding that, for example, women experience more sleep disruptions as the baby gets larger and more active. "But, surprisingly, the literature has not had a real consensus about what exactly happens to sleep in pregnancy," he said. Using imprecise methods to measure sleep habits, such as questionnaires, has not provided adequate answers.

The researchers were surprised at how strongly deviations from the normal pattern of sleep and physical activity could predict preterm birth. If the machine-learning model classified a woman as sleeping better and being more physically active than usual for her stage of pregnancy, this was linked with a 48% reduction in risk for preterm delivery. Conversely, if the model classified a woman as sleeping worse and being less physically active than usual for her stage of pregnancy, her risk for preterm delivery was 44% higher than for pregnant women with typical sleep and activity patterns.

Strong clues for preventing prematurity

"This is exciting preliminary data," Aghaeepour said. The results suggest that scientists should run studies to test whether tracking and modifying pregnant women's sleep or physical activity could their lower prematurity risk, he said, adding, "It's telling us where to go for future interventions."

The circadian clock regulates several other biological pathways implicated in premature birth, such as those regulating inflammation and the immune response, the scientists said. They plan to test whether improving sleep and physical activity in pregnancy could modify other key pathways, such as those controlling inflammation.

"Our feeling is that if we look at this overarching regulator, we may be able to control individual systems that lead to preterm birth," England said.

Although the findings are at an early stage, and more work is needed to understand their implications for preventing prematurity, there's little risk in advising pregnant women to maintain good sleep habits now, she added. For instance, women should try to maintain consistent bedtimes and wake-up times, get enough sleep, and get some natural light during the day to help regulate their body clock.

"I tell everyone who is pregnant, 'I hope you keep a regular sleep schedule,'" England said.

"If we can use sleep and physical activity to modulate biology in the right direction, it could be a great intervention for reducing the rate of preterm birth," Aghaeepour added.

https://www.sciencedaily.com/releases/2023/09/230928152205.htm

College athletes experience worse post-injury outcomes for concussions suffered outside of sports

Female athletes also had more severe symptoms associated with these injuries

September 20, 2023

Science Daily/Children's Hospital of Philadelphia

Researchers from Children's Hospital of Philadelphia (CHOP) found that college athletes had worse post-injury outcomes related to concussions they experienced outside of sports than those they experienced while playing sports. Additionally, female athletes who sustained their injury outside of sports had more severe symptoms and more days in sports lost to injury relative to male athletes. These findings suggest the need for improved concussion recognition, reporting, and monitoring outside of sports.

The study was recently published online by the Journal of Athletic Training.

Concussions have the potential to impact the daily function and quality of life of those who sustain them. Prompt recognition of symptoms and early access to care can help minimize those effects. Most concussion research has primarily focused on injuries that occur while playing sports, but those studies often exclude concussions that can happen outside of sports, usually the result of falls or car crashes. Some research has indicated that patients with non-sports-related concussions have worse outcomes, but research into those effects in college-age patients is very limited.

"Patients who experience a concussion outside of sports may lack the resources that athletes who sustain their injury on the field have for concussion care, like immediate access to health care providers such as athletic trainers," said study first author Patricia Roby, PhD, an injury scientist who conducted this research while she was a postdoctoral fellow at CHOP.

To help address this gap in knowledge, researchers analyzed data from the National Collegiate Athletic Association-Department of Defense Concussion Assessment, Research, and Education (CARE) Consortium. A total of 3,500 college athletes were included in the study, including 555 that experienced a non-sports-related concussion. More than 40% of athletes included were female so that potential differences in recovery between males and females could be explored.

The study found that athletes who experienced non-sports-related concussions were less likely to report their injuries immediately, potentially due to lack of recognition of symptoms outside of the sport setting or hesitation to report the injury caused by unusual or careless mechanisms. Athletes who sustained non-sports-related concussions reported greater severity of their symptoms, more days with symptoms, and more days in sports lost to injury relative to patients who experienced sports-related concussions, and these findings were even more true in female patients compared with male patients.

"Our findings show that non-sports mechanisms of injury for concussion are an important consideration in college age young adults, something we had already described in our research in younger children. There is an opportunity to improve clinical outcomes by increasing awareness and education around concussions that happen outside of sports and reducing healthcare reporting barriers in this older age group as well," said senior study author Christina L. Master, MD, clinical director of the Minds Matter Concussion Program at CHOP. "Additionally, our findings related to sex differences in the trajectory of these injuries warrant additional investigation to see the extent to which reporting behaviors and access to medical teams are contributing to this disparity in outcomes."

https://www.sciencedaily.com/releases/2023/09/230920152424.htm

New parent? Night shift? New analysis suggests ideal nap strategy to survive all-nighters

September 15, 2023

Science Daily/Hiroshima University

New analysis of pilot studies on night shift naps conducted from 2012 to 2018 revealed the ideal snoozing strategy that might help counteract drowsiness and fatigue during a 16-hour overnight duty. The findings can also benefit new parents.

Reanalysis of data showed that when staying up all night, scheduling two nap sessions -- a 90-minute one followed by a quick 30-minute shut-eye later -- is the optimal choice over a single 120-minute snooze in putting off drowsiness and fatigue. The study was published in the journal Scientific Reports.

"A 90-minute nap to maintain long-term performance and a 30-minute nap to maintain lower fatigue levels and fast reactions, as a strategic combination of naps, can be valuable for early morning work efficiency and safety," said study sole author Sanae Oriyama, a nursing science professor at Hiroshima University's Graduate School of Biomedical and Health Sciences.

Shift work is a norm in emergency sectors such as healthcare where round-the-clock access to services can be life-saving. And working double shifts on nontraditional hours isn't unheard of among medical professionals. However, night shift work is also known to increase the risk for sleep-related physical and mental health disorders and impair job performance.

During the daytime, our light-sensitive internal clock activates wakefulness. The opposite happens at nighttime when alertness dims as our biorhythm readies to switch off, elevating the likelihood of errors and accidents. In the medical field, this may inadvertently lead to serious harm to patients or to oneself. Naps are usually taken by shift workers to offset disruptions to the body clock.

In Japan, nurses are typically allowed to sleep up to two hours during 16-hour night shifts. Oriyama wanted to find out which napping schedule is the best in fighting off sleepiness and diminished cognitive function during such grueling work hours. And while at it, figure out how sleep quality factors in.

Single versus split naps

Oriyama reexamined past pilot studies she co-authored to compare alertness and cognitive performance after taking a nap and throughout a simulated 4 p.m. to 9 a.m. shift. The one-nap condition experiment was conducted in 2012, the two-nap in 2014, and the no-nap in 2018.

"I want to be able to combine multiple naps, depending on the type of work and time of day, and choose naps that are effective at reducing drowsiness, fatigue, and maintaining performance," she said.

She found that those who took a single 120-minute nap ending at midnight experienced worse drowsiness as soon as 4 a.m. and lasted until the end of the shift. However, participants who scheduled two naps -- the 90-minute one lasting until midnight and the 30-minute one ending at 3 a.m. -- staved off drowsiness until 6 a.m. Oriyama suggested adding an extra 30 minutes of shut-eye between 5-6 a.m. given that drowsiness might shoot up from 7-8 a.m.

As for fatigue, although all nap groups expressed significantly heightened levels of it from 4-9 a.m., the two-nap group experienced it at an intensity lower than the rest.

"During a night shift that, for example, lasts from 4 p.m. to 9 a.m. the next morning, a split nap of 90 minutes and 30 minutes, ending at 12 a.m. and 3 a.m., respectively, is thought to be more effective than a 120-minute monophasic nap ending at 12 a.m. when tasks requiring quick responses to maintain a high level of safety are scheduled between 2 a.m. and 9 a.m.," Oriyama said.

Finding the best nap length, timing

Both the single and split naps did not result in improved cognitive task performance. However, Oriyama noted that those who took longer to fall asleep during the 90-minute nap session showed poorer scores in the Uchida-Kraepelin test (UKT), a timed basic math exam meant to measure speed and accuracy in performing a task.

It takes 90 minutes to complete a full sleep cycle. And waking up before it is finished could exacerbate sleep inertia, the grogginess and disorientation felt upon first waking up. Similarly, the study found that if total sleep time is prolonged, fatigue and drowsiness could also increase.

Meanwhile, past research showed that a nap of 30 minutes or less could help boost vigilance, alertness, and energy levels.

The study also found that the timing of your nap plays a crucial role: the later you take it, the more potent it is in fending off sleepiness and exhaustion. However, delaying it too much could interfere with your focus as your sleep drive builds up.

"Hence, the ideal time for taking a nap and the ideal nap schedule during long night shifts need further elucidation," Oriyama said.

Beneficial for new parents, too

Oriyama said her findings could also be helpful to new parents.

"The results of this study can be applied not only to night shift workers but also to minimize sleep deprivation fatigue in mothers raising infants."

A total of 41 females in their 20s participated in the studies. Research participants were invited to a windowless and soundproofed laboratory for a 16-hour night shift simulation. The room temperature was kept at a comfortable 26 degrees Celsius and light intensity above work desks was set at 200 lux, the typical illuminance level in offices. All took the UKT each hour. Their hourly temperature, self-reported drowsiness and fatigue levels, heart rate, and blood pressure were also measured. After the tests, participants have free time to do anything they want on their desks like reading, drawing, or drinking water. During the scheduled nap time, they moved to a neighboring bedroom where they were allowed to darken the light according to their preference. Their sleep parameters were measured during this time.

https://www.sciencedaily.com/releases/2023/09/230915105258.htm

How education, work and motherhood shape women's life 'pathways'

September 13, 2023

Science Daily/North Carolina State University

A new study from North Carolina State University and Duke University offers insights into the ways that education, work and motherhood shape the lives of women in the United States. In a longitudinal study of more than 8,100 women, the researchers found seven "pathways" that illustrate the way major life events can have long-term ripple effects.

"Our goal here was to examine how family, work and education influence each other in the lives of women, rather than viewing education as a separate process from work and family," says Anna Manzoni, co-author of a paper on the study and an associate professor of sociology at NC State. "Our approach highlights the fluidity of education in many women's lives, and challenges the idea that completing one's education and transitioning from school to a full-time job are essential elements of how we define adulthood."

For the study, researchers examined data from 8,101 women who participated in the National Longitudinal Study of Adolescent to Adult Health, which is a nationally representative panel study that followed people in the United States from youth through adulthood.

The researchers then conducted analyses of these data to find patterns and subgroups among study participants, which helped them identify distinct pathways or commonalities among subgroups. The researchers also assessed the extent to which these pathways related to the race and socioeconomic class of the study participants.

"We found that women's lives tend to take one of seven pathways, with six of those pathways broadly defined by when or if women become parents," Manzoni says. "These pathways really underscore the extent to which specific life events, opportunities or constraints can shape later patterns in women's lives. However, it's important to recognize that there are notable nuances in the way women's lives end up unfolding in more ways than one."

The first three pathways all include women who became parents between the ages of 18 and 25:

• Early Mothers with High School Interrupted (making up 13.29% of participants);

• Early Mothers with Limited Education (13.01%), which refers to women who obtained a high school diploma or GED;

• Early Mothers with Continuing Education (19.31%).

The second three pathways include women who got college degrees by the time they were 25:

• College then Work Focused (11.95%);

• College then Family Focused (8.97%); and

• Graduate Degree Professionals (13.31%).

The seventh pathway was Independents with Continuing Education (20.17%), which is largely made up of women who pursue education at community colleges and vocational schools into adulthood and are unlikely to marry or have children until they are in their 30s and 40s.

"These groups are based on various longitudinal patterns that we observe across the life course," says Jane Bo-Hyeong Lee, co-author of the paper and a research associate in Duke University's Center for Health Policy & Inequalities Research. "For example, about 24% of women in the Early Mothers with Limited Education pathway went on to get associate's degrees by the time they were in their late 30s or early 40s. However, this pattern is very different from that of women who postponed starting a family until they'd completed an advanced degree."

"Much of this is informed by socioeconomic background and the resources that women have access to," says Manzoni. "For example, the three college-centered pathways largely reflect the experiences of women who come from privileged socioeconomic backgrounds.

"This work is important because it provides a structured way of understanding the ways in which family, work and education influence each other in the lives of women," Manzoni says.

"Our work builds on previous research, many of which use qualitative methods or cross-sectional data," Lee adds. "We have the advantage of using a nationally representative dataset that followed these women for many years."

https://www.sciencedaily.com/releases/2023/09/230913122644.htm

Toddlers learn to reason logically before they learn to speak

September 5, 2023

Science Daily/Universitat Pompeu Fabra - Barcelona

Nineteen-month-old toddlers already use natural logical thinking, even before they learn to speak, to deal with uncertainties about the world. This natural logic contributes to their learning process, both in terms of language and in other fields of knowledge, according to a new study.

How do we learn to speak during childhood or how do we acquire knowledge about the world around us? Toddlers' social interactions in their social and family environment and in schools help to explain this, but they are not the only factors involved. Natural logical thinking, which manifests itself from a very early age and does not depend on knowledge of language, also facilitates the learning process, according to a study led by UPF's Center for Brain and Cognition, the results of which have been published this Friday, 1 September, in the journal Current Biology.

The study focuses on a question that still generates debate among neuroscientists: whether infants who have not yet learned to speak (or are developing speech) are capable of logical reasoning. This pioneering research shows that this natural logical reasoning exists from at least 19 months of age, does not depend on knowledge of language and is developed mainly through the strategy of exclusion by elimination. In other words, if toddlers are faced with an unknown reality, they would try to analyse it and reach some conclusion about it by ruling out the options that are not possible, according to their level of knowledge at the time.

The results of the paper are presented in the article entitled The scope and role of deduction in infant cognition, written by Kinga Anna Bohus, Nicolo Cesana-Arlotti, Ana Martín-Salguero and Luca Lorenzo Bonatti. The principal researcher, L. Bonatti (ICREA), is the director of the Reasoning and Infant Cognition (RICO) research group at the Center for Brain and Cognition (CBC) at UPF. Kinga Anna Bohus (main author) also belongs to the group. N. Cesana-Arlotti and Ana Martín-Salguero, previously linked to the CBC at UPF, are currently researchers at Yale University (USA) and at the École Normale Supérieure in Paris.

Toddlers tend to solve uncertainties by ruling out impossible options according to the level of knowledge they have at any given moment

The study analyses the importance of two strategies for infants to deal with uncertainties: association and exclusion (or disjunction elimination). The first strategy would mean that toddlers hearing a new word that may refer to two unfamiliar objects that they can see, mentally associate the term with each of them. Subsequently, they would associate the term with the object with which this name fits better.

The second strategy (exclusion) explains how a toddler can learn a new word through logical reasoning by eliminating alternatives. For example, if they see two objects (A and B) and hear an unknown term that they know is not A (because they know the name of A), they will determine that it is the name of B. This is the predominant strategy, according to the results of the study.

Two experiments to analyse toddlers' natural logic posed with known and unknown objects and terms

The research team conducted two different experiments, the first with 61 monolingual (26) and bilingual (35) 19-month-old toddlers and the second with 33 (19 mono and 14 bilingual). The analysis of each group was crucial to determine whether deductive processes depend on linguistic experience.

In the first experiment, the participants were shown two objects, which they had to associate with one of the words they heard, through different tests. In the first test, they had to look at two objects they knew (e.g., a spoon and a biscuit) and, upon hearing a term (e.g., spoon), associate it with one of the two. In the second test, the infants were shown an object they knew (e.g., an apple) and an object they did not know (e.g., a carburettor), and they heard the word corresponding to the known object (apple), which they had to identify. The third test was the same as the second, except that the word heard corresponded to the unknown word (e.g., carburettor).

In the second experiment, two objects or animate beings were used (for example, an umbrella and a figure of a boy), each associated with a sound. Subsequently, the two objects were covered so that the infant could not see them and one of them was placed in a glass. When they were uncovered, the toddler could only see one of the two objects and had to guess, by elimination, which one was inside the glass. In a subsequent test (with the two objects covered and without changing their position), the infant listened to the sound associated with one of them and it was analysed whether he/she looked in the direction of the correct object.

In all these tests, their gaze movement patterns were assessed. For example, when reasoning by exclusion, toddlers look at object A and, if they rule out that the term they have heard refers to it, then they turn their gaze towards B. This is known as the double check strategy.

There are no relevant differences in the logic of monolingual and bilingual toddlers

The main author of the research, Kinga Anna Bohus, summarizes the main findings of the study as follows: "We studied the presence of the concept of logical disjunction in 19-month-old infants. In a word-referent mapping task, both bilingual and monolingual infants display a pattern of oculomotor inspection previously found to be a hallmark of disjunctive reasoning in adults and children."

In short, the results of the study show no relevant differences between the logical reasoning of monolingual and bilingual toddlers, which confirms that it does not depend on linguistic knowledge. This natural logical thinking could be present before the age of 19 months, although there is still not enough scientific evidence to demonstrate its presence at earlier ages.

https://www.sciencedaily.com/releases/2023/09/230905125028.htm

Adding complex component of milk to infant formula confers long-term cognitive benefits for bottle-fed babies

August 31, 2023

Science Daily/University of Kansas

New research has shown how a complex component of milk that can be added to infant formula has been shown to confer long-term cognitive benefits, including measures of intelligence and executive function in children.

Breast milk is widely acknowledged as the most beneficial nutrition for infants, but many families face medical or logistical challenges in breastfeeding. In the U.S., just 45% of infants continue to be exclusively breastfed at 3 months of age, according to the Centers for Disease Control.

For decades, researchers have sought to create a viable complement or alternative to breast milk to give children their best start for healthy development. New research out of the University of Kansas has shown how a complex component of milk that can be added to infant formula has been shown to confer long-term cognitive benefits, including measures of intelligence and executive function in children.

The research by John Colombo, KU Life Span Institute director and investigator, along with colleagues at Mead Johnson Nutrition and in Shanghai, China, adds to the growing scientific support for the importance of ingredients found in milk fat globule membrane (MFGM) in early human development.

The study, which was published in the Journal of Pediatrics, showed that feeding infants formula supplemented with MFGM and lactoferrin for 12 months raised IQ by 5 points at 5 ½ years of age. The effects were most evident in tests of children's speed of processing information and visual-spatial skills. Significant differences were also seen in children's performance on tests of executive function, which are complex skills involving rule learning and inhibition.

All forms of mammalian milk contain large fat globules that are surrounded by a membrane composed of a variety of nutrients important to human nutrition and brain development, Colombo said. When milk-based infant formula is manufactured, the membrane has typically been removed during processing.

"No one thought much about this membrane," Colombo said, "until chemical analyses showed that it's remarkably complex and full of components that potentially contribute to health and brain development."

The 2023 study was a follow-up to one that Colombo also co-wrote with colleagues in Shanghai, China, published in the Journal of Pediatrics in 2019. That study showed that babies who were fed formula with added bovine MFGM and lactoferrin had higher scores on neurodevelopmental tests during the first year and on some aspects of language at 18 months of age.

The global nutrition research community has been looking at MFGM for about a decade, Colombo said. Because the membrane is made up of several different components, it isn't known whether one of the components is responsible for these benefits, or whether the entire package of nutrients act together to improve brain and behavioral development.

These benefits were seen in children long after the end of formula feeding at 12 months of age.

"This is consistent with the idea that early exposure to these nutritional components contribute to the long-term structure and function of the brain," said Colombo, who has spent much of his career researching the importance of early experience in shaping later development.

https://www.sciencedaily.com/releases/2023/08/230831142823.htm

First-time fathers seem to experience a steeper decline in relationship satisfaction in the first two years post-partum than second-time fathers

By 14 months postpartum, second-time fathers' reported relationship satisfaction had increased back to baseline

August 30, 2023

Science Daily/PLOS

First-time fathers seem to experience a steeper decline in relationship satisfaction in the first two years post-partum than second-time fathers, who appear to recover lost relationship satisfaction by the time their second child is 14 months old, according to a study published August 30, 2023 in the open-access journal PLOS ONE by Judith T. Mack and Lena Brunke from Technische Universität Dresden, Germany, and colleagues.

Having a strong primary relationship can help couples more successfully weather potentially-challenging transitions like the birth of a child. Most research on postpartum relationship satisfaction has focused on mothers after the birth of their first child; in this study the authors studied fathers' experiences of relationship satisfaction before and after the birth of a first or second child. They also assessed how variables like age, education, income, relationship duration, marital status, child's biological sex, or child's temperament might predict relationship satisfaction for fathers over this period.

The authors analyzed survey data from 500 first-time fathers and 106 fathers expecting their second child, collected over 2017-2020 as part of the ongoing, prospective, longitudinal Dresden Study of Parenting, Work, and Mental Health. The survey asked about relationship satisfaction two months before the birth of the child, eight weeks postpartum, 14 months postpartum, and two years postpartum; the eight weeks postpartum check-in also asked about the child's temperament and biological sex.

The first survey check-in collected the demographic information studied. Having a child was associated with a decline in relationship satisfaction for both first- or second-time fathers. However, first-time fathers showed a higher level of relationship satisfaction before birth, and a steeper decline in satisfaction after birth. At eight weeks postpartum, first-time fathers still tended to report higher relationship satisfaction than second-time fathers, but satisfaction continued to decline for first-time fathers up until 14 months postpartum. In contrast, second-time fathers tended to report an increase in relationship satisfaction by 14 months that continued through the two year check-in. During both these points, second-time fathers had higher relationship satisfaction scores than first-time fathers -- scores which had returned to their original baseline levels. This study is the first to show this type of satisfaction increase, which has not been reported in studies of second-time mothers. This study found no significant association between reported relationship satisfaction and the other variables studied besides relationship duration: couples in longer relationships tended to report lower relationship satisfaction initially.

The authors suggest that fathers becoming parents for the first time should be prepared for expected changes in their relationship -- and know that, should they choose to have another child, the changes a newborn brings will likely be easier to weather.

The authors add: "The transition to parenthood can negatively affect the relationship satisfaction of fathers, more so for first than for second-time fathers, however, this can recover over time. Preparation and anticipation may be key."

https://www.sciencedaily.com/releases/2023/08/230830151756.htm

Stress and insomnia linked to irregular heart rhythms after menopause

August 30, 2023

Science Daily/American Heart Association

A study of more than 83,000 questionnaires by women ages 50-79, found more than 25% developed irregular heart rhythms, known as atrial fibrillation, which may increase their risk for stroke and heart failure

After menopause an estimated 1 in 4 women may develop irregular heart rhythms -- known as atrial fibrillation -- in their lifetime, with stressful life events and insomnia being major contributing factors, according to new research published today in the Journal of the American Heart Association, an open access, peer-reviewed journal of the American Heart Association.

Atrial fibrillation may lead to blood clots, stroke, heart failure or other cardiovascular complications. It primarily affects older adults, and more than 12 million people in the U.S. are expected to develop atrial fibrillation by 2030, according to the American Heart Association.

"In my general cardiology practice, I see many postmenopausal women with picture perfect physical health who struggle with poor sleep and negative psychological emotional feelings or experience, which we now know may put them at risk for developing atrial fibrillation," said lead study author Susan X. Zhao, M.D., a cardiologist at Santa Clara Valley Medical Center in San Jose, California. "I strongly believe that in addition to age, genetic and other heart-health related risk factors, psychosocial factors are the missing piece to the puzzle of the genesis of atrial fibrillation."

Researchers reviewed data from more than 83,000 questionnaires by women ages 50-79 from the Women's Health Initiative, a major U.S. study. Participants were asked a series of questions in key categories: stressful life events, their sense of optimism, social support and insomnia. Questions about stressful life events addressed topics such as loss of a loved one; illness; divorce; financial pressure; and domestic, verbal, physical or sexual abuse. Questions about sleeping habits focused on if participants had trouble falling asleep, wake up several times during the night and overall sleep quality, for example. Questions about participants' outlook on life and social supports addressed having friends to talk with during and about difficult or stressful situations; a sense of optimism such as believing good things are on the horizon; and having help with daily chores.

During approximately a decade of follow-up, the study found:

• About 25% or 23,954 women developed atrial fibrillation.

• A two-cluster system (the stress cluster and the strain cluster).

• For each additional point on the insomnia scale, there is a 4% higher likelihood of developing atrial fibrillation. Similarly, for each additional point on the stressful life event scale, there is a 2% higher likelihood of having atrial fibrillation.

"The heart and brain connection has been long established in many conditions," Zhao said. "Atrial fibrillation is a disease of the electrical conduction system and is prone to hormonal changes stemming from stress and poor sleep. These common pathways likely underpin the association between stress and insomnia with atrial fibrillation."

Researchers noted that stressful life events, poor sleep and feelings, such as depression, anxiety or feeling overwhelmed by one's circumstances, are often interrelated. It's difficult to know whether these factors accumulate gradually over the years to increase the risk of atrial fibrillation as women age.

Chronic stress has not been consistently associated with atrial fibrillation, and the researchers note that a limitation of their study is that it relied on patient questionnaires utilized at the start of the study. Stressful life events, however, though significant and traumatic, may not be long lasting, Zhao notes. Further research is needed to confirm these associations and evaluate whether customized stress-relieving interventions may modify atrial fibrillation risk.

Study details and background:

• Participants were recruited between 1994 and 1998.

• The average age of the 83,736 women included in the study was about 64 years old. Approximately 88% of the group were women who self-identified as white; 7.2% identified as Black women; and 2.9% self-identified as Hispanic women.

• As women live longer, they may face higher risk and poorer outcomes associated with atrial fibrillation. While high blood pressure, obesity, Type 2 diabetes and heart failure are recognized risk factors, more research is needed about how the exposure to psychosocial stress and overall emotional well-being over time may affect the potential development of atrial fibrillation.

https://www.sciencedaily.com/releases/2023/08/230830131847.htm

Women more severely affected by chronic fatigue syndrome

Science Daily/University of Edinburgh

Women with ME/CFS tend to have more symptoms and co-occurring conditions than men, according to initial results from the world's largest study of the disease.

It has long been known that women are more likely to have ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome) but the DecodeME study has shown for the first time how their experience differs from men.

The study reveals that women who have ME/CFS -- a long-term neurological condition where an excessive increase in symptoms can be triggered by normal levels of exertion -- for more than 10 years are more likely to experience increasingly severe symptoms as they age.

Experts say that gaining a better understanding of how ME/CFS affects people is the first step to developing effective treatment options.

To aid their efforts, the study team from the University of Edinburgh are calling on more people with ME/CFS, aged 16 and over and based in the UK to take part in the study.

Experts analysed anonymous survey questionnaires from more than 17,000 people with ME/CFS. They included information on how long the respondent has had ME/CFS symptoms, when they were diagnosed, and whether they had any co-occurring conditions.

The study confirmed the well-established sex bias amongst ME/CFS patients, with women making up 83.5 per cent of respondents.

Two-thirds (66.7 per cent) of women, and slightly more than half (52.7 per cent) of men, reported at least one active co-occurring condition. Similarly, 39.2 per cent of women and 28.6 per cent of men reported at least one inactive co-occurring condition.

A condition was considered active if the participant had experienced symptoms in the preceding six months.

The most common active co-occurring condition was irritable bowel syndrome (41.3 per cent), with clinical depression (32.4 per cent), fibromyalgia (29.5 per cent), anaemia (14.1 per cent) and hypothyroidism (12.8 per cent) also featuring prominently.

Women also reported, on average, more symptoms than men -- 42 compared with 36.

The most common of these symptoms were brain fog -- a term commonly used to describe the cognitive impairment experienced by participants -- unrefreshing sleep, and muscle pain.

Participants were also asked to define the severity of their illness from mild to very severe using definitions from the UK's National Institute for Health and Care Excellence (NICE) guidelines.

Experts identified that being a woman and having ME/CFS for more than 10 years are risk factors for severe illness, with symptoms increasing in intensity as they age.

To increase their understanding of the disease, the study team want to recruit a further 6000 participants to the study.  

In the next stage of the project experts will study at least 20,000 individual DNA samples to explore whether the disease is partly genetic and, if so, research its cause.

ME/CFS is estimated to affect more than one quarter of a million people in the UK, of all ages and from all social and economic backgrounds.

Its key feature, called post-exertional malaise, is a delayed dramatic worsening of symptoms following minor physical effort. Other symptoms include pain, brain fog and extreme energy limitation that does not improve with rest. Causes are unknown and there is currently no diagnostic test or cure.

Initial results from the study have been posted on NIHR Open Research: https://openresearch.nihr.ac.uk/articles/3-20.

As well as the University of Edinburgh, the study involves the charity Action for M.E., the Forward M.E. alliance of UK charities, and people who have experienced the condition. The study is funded by the Medical Research Council and the National Institute for Health and Care Research.

Professor Chris Ponting, study lead from the MRC Human Genetics Unit at the University of Edinburgh's Institute of Genetics and Cancer, said: "ME/CFS is a devastating disease affecting a UK population the size of Derby. We discovered that the disease is worse for women, in older people, and many years after their ME/CFS started. Our hope is that DecodeME's genetic results will shed light on why certain groups are more susceptible to ME/CFS than others."

Sonya Chowdhury, Chief Executive of Action for M.E. and Chair of the Management Group of the study, added: "These findings highlight the very serious impact ME/CFS has on women who are disproportionately affected. It's important to also recognise the impact that it has on men who have ME/CFS, and we thank the 20,000 men and women who have already signed up to take part in this very important study. But we still need more to join us so if you are 16 or older, live in the UK and have a diagnosis of ME/CFS, please do take part now to help us decode ME at www.decodeme.org.uk/portal."

https://www.sciencedaily.com/releases/2023/08/230824111857.htm

Brain cells of males and females respond differently to chronic stress

August 9, 2023

Science Daily/Weizmann Institute of Science

Scientific excellence requires diversity -- research conducted by men and women, by people from different backgrounds and with varied worldviews. The need for diversity extends to scientific experiments themselves, but even today the vast majority of studies in the life sciences are done on male mice only, which could harm the findings, as well as our ability to extrapolate from them to humans. A new study by researchers from the Weizmann Institute of Science addresses this challenge, revealing in unprecedented detail how the brains of male and female mice respond differently to stress. In the study, published in Cell Reports, researchers from Prof. Alon Chen's joint laboratory at the Weizmann Institute and the Max Planck Institute of Psychiatry in Munich discovered that a subcategory of brain cells responds to stress in a totally different manner in males and females. The findings could lead to a better understanding of health conditions affected by chronic stress, such as anxiety, depression and even obesity and diabetes, and they could pave the way toward personalized therapies for these disorders.

Mental and physical disorders caused by chronic stress are constantly on the rise, putting a significant strain on society. They affect both men and women, but not necessarily in the same way. Although plenty of evidence suggests that men and women deal differently with stress, the causes of these differences are not yet fully understood, and in any event, personalized treatments for men and women are still beyond the reach of medicine. But researchers from Chen's laboratory, which specializes in studying the response to stress, hypothesized that innovative research methods could help to change the picture. Previous studies in other labs had uncovered certain sex differences in the response to stress, but those findings were obtained using research methods that could mask significant differences in the responses of specific cells or even entirely erase the roles played by relatively rare cells. Chen's laboratory, in contrast, uses advanced methods that allow scientists to analyze brain activity at an unprecedented resolution -- on the level of the individual cell -- and could therefore shed new light on the differences between the sexes.

"We turned the most sensitive research lens possible onto the area of the brain that acts as a central hub of the stress response in mammals, the paraventricular nucleus (PVN) of the hypothalamus," says Dr. Elena Brivio, who led the study. "By sequencing the RNA molecules in that part of the brain on the level of the individual cell, we were able to map the stress response in male and female mice along three main axes: how each cell type in that part of the brain responds to stress, how each cell type previously exposed to chronic stress responds to a new stress experience and how these responses differ between males and females."

The researchers mapped out gene expression in more than 35,000 individual cells, generating a huge amount of data that provides a picture of stress response that's unprecedented in its scope and in highlighting the differences between how males and females perceive and process stress. As part of the study, and in keeping with the principles of open-access science, the researchers decided to make the entire detailed mapping publicly available on a dedicated interactive website, which went live at the same time the study was published, providing other researchers with convenient, user-friendly access to the data. "The website will, for example, allow researchers who are focusing on a specific gene to see how that gene's expression changes in a certain cell type in response to stress, in males as well as females," Brivio explains.

The comprehensive mapping has already allowed the researchers to identify a long list of differences in gene expression -- between males and females, and between chronic and acute stress. The data showed, inter alia, that certain brain cells respond differently to stress in males and females: Some cells are more susceptible to stress in females and some to stress in males. The most significant difference was found in a type of brain cell called the oligodendrocyte -- a subtype of glial cell that provides support to nerve cells and plays an important role in regulating brain activity. In males, exposure to stress conditions, especially chronic stress, changed not only the gene expression in these cells and their interactions with surrounding nerve cells but also their very structure. In females, however, no significant change was observed in these cells, and they were not susceptible to stress exposure. "Neurons attract most of the scientific attention, but they only make up approximately a third of all cells in the brain. The method we implemented allows us to see a much richer and fuller picture, including all the cell types and their interactions in the part of the brain under study," says Dr. Juan Pablo Lopez, a former postdoctoral fellow in Chen's group and now the head of a research group at the Department of Neuroscience of the Karolinska Institute in Sweden.

Basic diversity

Until the 1980s, clinical trials of new drugs were conducted on men alone. The accepted view was that including women was unnecessary, and that it would only complicate the research, bringing into play new variables such as menstruation and hormonal changes. For the same reasons, preclinical studies avoided using female animals until very recently. But it's now known that the variability among male animals, on a molecular and behavioral level, is usually greater than among females, so there is no reason to suppose that females would complicate the experiments any more than males. Nonetheless, in basic research it's still common to conduct experiments only on males. "Our findings show that, when it comes to stress-related health conditions, from depression to diabetes, it's very important to take the sex variable into account, since it has a significant impact on how different brain cells respond to stress," Chen explains. "Even if a study does not specifically focus on the differences between males and females, it's essential to include female animals in the research, especially in neuroscience and behavioral science, just as it is important to implement the most sensitive research methods, in order to obtain as complete a picture of brain activity as possible," Brivio adds.

https://www.sciencedaily.com/releases/2023/08/230809130625.htm