No safe amount of alcohol during pregnancy

Brain connectivity issues found in children who have experienced prenatal alcohol exposure

April 26, 2019

Science Daily/American Institute of Physics

An international group of researchers has taken one of the first major steps in finding the biological changes in the brain that drive fetal alcohol spectrum disorder (FASD). New work using chaos theory to analyze brain signals, discussed this month in the journal Chaos, from AIP Publishing, shows the long-term effects.

Researchers found that teenagers who were exposed to alcohol while in the womb showed altered brain connections that were consistent with impaired cognitive performance. Their findings were reached by measuring the responses from a brain imaging technique called magnetoencephalography (MEG) and then analyzing them with tools developed using chaos theory.

FASD is one of the leading causes of intellectual disability worldwide and is linked to a wide array of neurological issues, including ADHD. While the prevailing theory links expectant mothers' alcohol consumption to cognitive impairments for children, questions about the extent of this effect remain. Despite the known link, researchers are uncertain about the precise mechanism by which alcohol alters the developing brain.

The group's efforts mark one of the first times researchers have been able to quantify the effects of alcohol exposure on the developing brain.

"The paper provides important integrative results for the field of FASD," said Julia Stephen, an author on the paper. "These results may then indicate that simple sensory measures may provide sensitivity for brain deficits that affect the broader cognitive domain."

Previous attempts to study the brain circuitry in affected individuals have been hampered by the difficulty of drawing conclusions from complicated MEG data.

To get to the heart of the problem, members of the team developed a sophisticated computer technique called Cortical Start Spatio-Temporal multidipole analysis that could identify which areas of the brain were active when research subjects were in the MEG machine.

After data from 19 FASD patients and 21 subjects without FASD was collected, the computational approach revealed several areas of the brain that showed impaired connectivity among the FASD group.

Subjects who were exposed to alcohol in the womb were more likely to have issues with connections through their corpus callosum, the band of brain tissue that connects the left and right halves of the brain. Deficits in this area have been reported in people with schizophrenia, multiple sclerosis, autism, depression and abnormalities in sensation.

"This work presents major evidence that children exposed to alcohol prenatally are at risk of suffering from impaired cognitive abilities and other secondary factors," said Lin Gao, an author on the paper. "Our study ... shows that there is no safe amount or safe stages during pregnancy for alcohol consumption."

The authors hope their work inspires other groups to conduct similarly collaborative research on diseases like FASD that benefit from drawing together medical and computational fields.

https://www.sciencedaily.com/releases/2019/04/190426150639.htm

Why does prenatal alcohol exposure increase the likelihood of addiction?

July 7, 2017

Science Daily/University at Buffalo

One of the many negative consequences when fetuses are exposed to alcohol in the womb is an increased risk for drug addiction later in life. Neuroscientists in the University at Buffalo Research Institute on Addictions are discovering why.

Through a research grant from the National Institute on Alcohol Abuse and Alcoholism (NIAAA) of the National Institutes of Health (NIH), Senior Research Scientist Roh-Yu Shen, PhD, is studying how prenatal alcohol exposure alters the reward system in the brain and how this change continues through adulthood.

The key appears to lie with endocannibinoids, cannabis-like chemicals that are produced by the brain itself.

"By understanding the role endocannibinoids play in increasing the brain's susceptibility to addiction, we can start developing drug therapies or other interventions to combat that effect and, perhaps, other negative consequences of prenatal alcohol exposure," Shen says.

Prenatal alcohol exposure is the leading preventable cause of birth defects and neurodevelopmental abnormalities in the United States. Fetal Alcohol Spectrum Disorders (FASD) cause cognitive and behavioral problems. In addition to increased vulnerability of alcohol and other substance use disorders, FASD can lead to other mental health issues including Attention Deficit Hyperactivity Disorder (ADHD), depression, anxiety and problems with impulse control.

"After the prenatal brain is exposed to alcohol, the endocannibinoids have a different effect on certain dopamine neurons which are involved in addicted behaviors than when brain is not exposed to alcohol," Shen says. "The end result is that the dopamine neurons in the brain become more sensitive to a drug of abuse's effect. So, later in life, a person needs much less drug use to become addicted."

Specifically, in the ventral tegmental area (VTA) of the brain, endocannibinoids play a significant role in weakening the excitatory synapses onto dopamine neurons. The VTA is the part of the brain implicated in addiction, attention and reward processes. However, in a brain prenatally exposed to alcohol, the effect of the endocannabinoids is reduced due to a decreased function of endocannabinoid receptors. As a result, the excitatory synapses lose the ability to be weakened and continue to strengthen, which Shen believes is a critical brain mechanism for increased addiction risk.

https://www.sciencedaily.com/releases/2017/07/170707211125.htm