Predisposition To Blackouts
Research indicates that some users of alcohol, particularly those with a history of blackouts, are predisposed to experience blackouts more frequently than others. One such study indicated a link between prenatal exposure to alcohol and vulnerability towards blackouts, in addition to the oft-cited link between this type of exposure and alcoholism. Alternatively, another study has indicated that there appears to be a genetic predisposition towards blacking out, suggesting that some individuals are made to be susceptible to alcohol-related amnesia.
From a neurobiological perspective, central serotonin (5-hydroxytryptamine, 5-HT) neurotransmission has been shown to modulate both alcohol consumption and impulsivity. Some variations in 5-HT neurotransmission may thus contribute to a risk of AD (alcohol dependence), especially the forms of AD associated with a high level of impulsivity 2.
As the extracellular concentration of 5-HT is regulated by the activity of the 5-HT transporter (5-HTT), the gene SLC6A4 encoding this protein represents an important potential candidate gene for AD risk. Using a meta-analysis approach, Feinn et al. found evidence for an association of the short allele of the 5-HTTLPR (SLC6A4) with AD, but the overall effect size estimated by odd ratios was found weak. As expected in a complex condition like alcohol dependence, the disagreement in the association between AD and 5-HTTLPR likely reflects the impossibility for a single genetic determinant to explain the whole of the risk.
Aside fro m chemical components which may cause a predisposition to alcohol dependence and blackouts, expectations of alcohol use may predispose drinkers toward alcoholism and blackouts. In a study of 123 college students significant correlations were found between students’ alcohol expectancies, level of alcohol abuse, and blackout history. The students who experienced blackouts (38.6%) had much higher positive alcohol expectancies than those without blackouts. Positive and negative expectancies were positively correlated among the no-blackout group, but negatively correlated among the blackout group.
Read more about this topic: Blackout (alcohol-related Amnesia)