Why being left-handed matters for mental health treatment
June 18, 2018
Science Daily/Cornell University
Treatment for the most common mental health problems could be ineffective or even detrimental to about 50 percent of the population, according to a radical new model of emotion in the brain.
Since the 1970s, hundreds of studies have suggested that each hemisphere of the brain is home to a specific type of emotion. Emotions linked to approaching and engaging with the world -- like happiness, pride and anger -- lives in the left side of the brain, while emotions associated with avoidance -- like disgust and fear -- are housed in the right.
But those studies were done almost exclusively on right-handed people. That simple fact has given us a skewed understanding of how emotion works in the brain, according to Daniel Casasanto, associate professor of human development and psychology at Cornell University.
That longstanding model is, in fact, reversed in left-handed people, whose emotions like alertness and determination are housed in the right side of their brains, Casasanto suggests in a new study. Even more radical: The location of a person's neural systems for emotion depends on whether they are left-handed, right-handed or somewhere in between, the research shows.
The study, "Approach motivation in human cerebral cortex," is published in Philosophical Transactions of the Royal Society B: Biological Sciences.
According to the new theory, called the "sword and shield hypothesis," the way we perform actions with our hands determines how emotions are organized in our brains. Sword fighters of old would wield their swords in their dominant hand to attack the enemy -- an approach action -- and raise their shields with their non-dominant hand to fend off attack -- an avoidance action. Consistent with these action habits, results show that approach emotions depend on the hemisphere of the brain that controls the dominant "sword" hand, and avoidance emotions on the hemisphere that controls the non-dominant "shield" hand.
The work has implications for a current treatment for recalcitrant anxiety and depression called neural therapy. Similar to the technique used in the study and approved by the Food and Drug Administration, it involves a mild electrical stimulation or a magnetic stimulation to the left side of the brain, to encourage approach-related emotions.
But Casasanto's work suggests the treatment could be damaging for left-handed patients. Stimulation on the left would decrease life-affirming approach emotions. "If you give left-handers the standard treatment, you're probably going to make them worse," Casasanto said.
"And because many people are neither strongly right- nor left-handed, the stimulation won't make any difference for them, because their approach emotions are distributed across both hemispheres," he said.
"This suggests strong righties should get the normal treatment, but they make up only 50 percent of the population. Strong lefties should get the opposite treatment, and people in the middle shouldn't get the treatment at all."
However, Casasanto cautions that this research studied only healthy participants and more work is needed to extend these findings to a clinical setting.
https://www.sciencedaily.com/releases/2018/06/180618222617.htm
Loneliness is bad for the heart
June 9, 2018
Science Daily/European Society of Cardiology
Loneliness is bad for the heart and a strong predictor of premature death, according to a new study. The study found that feeling lonely was a stronger predictor of poor outcomes than living alone, in both men and women.
"Loneliness is more common today than ever before, and more people live alone," said Anne Vinggaard Christensen, study author and PhD student, The Heart Centre, Copenhagen University Hospital, Denmark. "Previous research has shown that loneliness and social isolation are linked with coronary heart disease and stroke, but this has not been investigated in patients with different types of cardiovascular disease."
The study investigated whether poor social network was associated with worse outcomes in 13,463 patients with ischaemic heart disease, arrhythmia (abnormal heart rhythm), heart failure, or heart valve disease. Data from national registers was linked with the DenHeart survey, which asked all patients discharged from April 2013 to April 2014 from five heart centres in Denmark to answer a questionnaire about their physical and mental health, lifestyle factors such as smoking, and social support.
Social support was measured using registry data on living alone or not, and survey questions about feeling lonely -- Do you have someone to talk to when you need it? Do you feel alone sometimes even though you want to be with someone? "It was important to collect information on both, since people may live alone but not feel lonely while others cohabit but do feel lonely," explained Ms Vinggaard Christensen.
Feeling lonely was associated with poor outcomes in all patients regardless of their type of heart disease, and even after adjusting for age, level of education, other diseases, body mass index, smoking, and alcohol intake. Loneliness was associated with a doubled mortality risk in women and nearly doubled risk in men. Both men and women who felt lonely were three times more likely to report symptoms of anxiety and depression, and had a significantly lower quality of life than those who did not feel lonely.
"Loneliness is a strong predictor of premature death, worse mental health, and lower quality of life in patients with cardiovascular disease, and a much stronger predictor than living alone, in both men and women," said Ms Vinggaard Christensen.
Ms Vinggaard Christensen noted that people with poor social support may have worse health outcomes because they have unhealthier lifestyles, are less compliant with treatment, and are more affected by stressful events. But she said: "We adjusted for lifestyle behaviours and many other factors in our analysis, and still found that loneliness is bad for health."
She concluded: "We live in a time when loneliness is more present and health providers should take this into account when assessing risk. Our study shows that asking two questions about social support provides a lot of information about the likelihood of having poor health outcomes."
European guidelines on cardiovascular prevention state that people who are isolated or disconnected from others are at increased risk of developing and dying prematurely from coronary artery disease. The guidelines recommend assessment of psychosocial risk factors in patients with established cardiovascular disease and those at high risk of developing cardiovascular disease.
https://www.sciencedaily.com/releases/2018/06/180609124652.htm
Common anesthetic procedure dramatically improves well being of veterans with PTSD
October 11, 2014
Science Daily/American Society of Anesthesiologists (ASA)
A single application of a common anesthetic procedure could be the answer to alleviating anxiety, depression and psychological pain in those suffering from chronic, extreme post-traumatic stress disorder (PTSD).
In a study presented at the ANESTHESIOLOGY™ 2014 annual meeting, researchers followed 12 patients with PTSD who had undergone a simple anesthetic procedure called a stellate ganglion block (SGB). This common procedure involves injecting a small amount of local anesthesia into the base of the neck. SGB is traditionally used to treat a variety of conditions, from pain syndromes to sleep disorders.
"While it doesn't cure the problem, we found that SGB appears to be a fast-acting and effective long-term treatment for chronic, extreme PTSD in veterans," said Michael T. Alkire, M.D., staff anesthesiologist at the Long Beach VA Healthcare System in California. "These improvements far outlasted what we would expect from SGB, which is usually used as a temporary nerve block and typically lasts three to five hours."
In the study, the patients each were given one SGB and followed closely with structured interviews and other psychological tests for six months after treatment. The positive effects of the SGB were evident often within minutes and resulted in significant improvement of scores for the Clinician Administered PTSD Score, or CAPS, the test used to measure the severity of PTSD.
Symptoms improved over time, and after one month, CAPS scores registered normal to mild PTSD levels for most of the patients. Positive effects were still seen at three months, but began fading and were generally gone by six months. Overall, 75 percent of the participants reported significant improvement of their PTSD symptoms after the SGB.
Data from the study further suggested that SGB might also be an effective initial treatment for depression and anxiety disorders.
"Further work is needed to identify which patients might respond best to this treatment as well as understand the mechanisms involved that produce such a rapid, dramatic and long-term change in psychological health for some patients," said Dr. Alkire, who also is a professor of anesthesiology at the University of California-Irvine.
http://www.sciencedaily.com/releases/2014/10/141011172042.htm