Craving for alcohol and pre-attentive processing of alcohol stimuli

The present study was designed to test the hypothesis of unconscious attending to alcohol-related information in alcoholics experiencing a high level of craving for alcohol. Subjects included a group of alcoholics (n=34) divided by a median split on a craving measure into two groups labeled as 'high craving' (n=18) and 'low craving' (n=16) alcoholics, and a non-alcoholic control group (n=39). The cardiovascular reactions of these groups were compared after their exposure to masked and unmasked alcohol and control stimuli. As expected the 'high craving' alcoholics showed an immediate heart rate deceleration after exposure to masked and non-consciously accessible alcohol pictures. The 'high craving' alcoholics reported a small but significant increase in difficulty resisting a drink after exposure to masked alcohol pictures. When the alcohol pictures were presented unmasked a significant increase was found in both high and low craving alcoholics on consciously expressed urges, fidgeting and reduced coping with temptation to drink. The 'high craving' alcoholics had lower tonic heart rate variability compared to the control group and the level of craving was positively associated with salivation during the exposure to all picture types. The findings generally support the psychobiological theory of craving, which suggests that the uncontrollability of the craving experience is rooted in unconscious processing of drug-related information.