Binge Alcohol Effects on the Prefrontal Cortex

Approximately 92% of U.S. adults who drink excessively report binge drinking in the past 30 days. Increased alcohol marketing in recent years has particularly targeted women, causing a 36% increase in the last 10 years in the number of women who are engaging in binge alcohol consumption. Since women appear to be more vulnerable to the harmful neurological effects of alcohol, this increase is of particular concern. One of the brain regions most affected by binge alcohol consumption is the frontal cortex, an area important for many functions and decision making of daily life. Loss of prefrontal grey matter resulting from heavy alcohol consumption has been documented, however this volume loss does not appear to be caused by a decrease in the number of prefrontal cortex neurons. This study aimed to determine whether the medial prefrontal cortex (mPFC) in female rats is more vulnerable to alcohol induced damage (compared to males), by examining neuronal volume and quantity as well as prefrontal- dependent behavioral tasks following binge alcohol exposure. To assess this, adult male and female Long-Evans rats were assigned to binge or control groups and exposed to ethanol using a well-established 4-day model of alcohol-induced neurodegeneration. Both male and female binged animals had significantly smaller average neuronal volumes than their respective control groups, as well as spatial working memory deficits detected during behavioral testing. No differences were found between binged male and binged female rats on neuronal volume, population or behavioral outcomes. These results support prior research indicating that frontal regions are vulnerable to binge alcohol damage.