A new study published in JNeurosci reports how experiences before birth may shape the brain and behavior later in life. Led by Mary Schneider and Alexander Converse at the University of Wisconsin-Madison, the interdisciplinary research examined how exposure to alcohol and stress during pregnancy affects rhesus monkey offspring once they reach adulthood.
How Alcohol and Stress Were Studied Before Birth
In the study, pregnant rhesus monkeys were placed into different conditions. Some consumed moderate amounts of alcohol, some were exposed to mild stress, and others experienced both. When the offspring became adults, researchers examined changes in the brain’s dopamine system and measured how the animals consumed alcohol.
Both prenatal alcohol exposure and prenatal stress altered the dopamine system in the adult offspring. Monkeys exposed to alcohol before birth also drank alcohol more quickly as adults. Notably, measurements of the dopamine system taken before the animals had any alcohol were able to predict their later drinking behavior. These findings align with evidence from human studies of alcohol use disorder and suggest that certain brain differences may be present even before problematic drinking begins.
Brain Changes That Continue With Drinking
As the adult offspring consumed alcohol, researchers observed additional changes in the dopamine system. These changes influenced how much alcohol each individual drank and differed from one animal to another. The research team suggests that these individualized brain responses to alcohol may help drive the shift from typical drinking patterns to alcohol use disorder in some individuals.
Implications for Pregnancy and Human Health
According to the researchers, the findings reinforce the message that drinking during pregnancy is not advisable, linking prenatal alcohol exposure to unhealthy drinking patterns later in life. While the study did not find a direct association between prenatal stress and adult drinking behavior, the authors note that prenatal stress may still affect other behaviors not examined in this work.
The researchers also emphasize that their experimental design closely reflects how prenatal alcohol exposure and stress occur in humans. This strengthens the clinical relevance of the findings and helps bridge the gap between animal research and human health outcomes