We find no effect of social deprivation or education on the association between verbal fluency and polygenic risk for alcohol dependence. Verbal fluency is believed to be a frontal lobe process (Fuster 2008) as patients with frontal lobe damage are significantly impaired on tests of phonemic word fluency (Robinson et al. 2012). Damage to the frontal lobes induces behaviour typically associated with addiction, such as the inability to defer immediate rewards for greater delayed rewards (Berlin, Rolls & Kischka 2004). Indeed, chronic alcohol consumption is associated with metabolic and morphological changes in the frontal lobes, particularly the prefrontal cortex (Adams et al. 1993; Pfefferbaum et al. 1997). Grey matter reductions in the prefrontal cortex of alcoholics are correlated with worse executive function (Chanraud et al. 2007). Here we show that polygenic risk for alcohol dependence is negatively associated with phonemic verbal fluency, suggesting that frontal lobe deficits may be pre‐existing risk factors for the development of alcohol dependence. However, because the present study is correlational in nature, evaluation of this relationship requires a prospective design in which cognitive function is evaluated prior to the onset of alcohol dependence.
