Do alcohol-dependent patients show different neural activation during response inhibition than healthy controls in an alcohol-related fMRI go/no-go-task?

RATIONALE: Alcohol dependence is associated with impaired response inhibition and heightened cue reactivity towards alcohol-related stimuli. Several brain areas, but mainly prefrontal structures, have been linked to response inhibition in addiction. This study aimed at combining both aspects: salience of drug-associated cues and response inhibition using a go/no-go task with alcohol-associated stimuli during functional magnetic resonance imaging (fMRI). OBJECTIVES: Nineteen abstinent alcohol-dependent patients (ADP) and 21 healthy control subjects (HC) were compared on blood oxygen level-dependent (BOLD) responses during successful inhibition of no-go stimuli and successful reactions to go stimuli. RESULTS: ADP and HC did not significantly differ in their behavioural performance in the task. However, both groups performed worse during the inhibition of alcoholic-associated stimuli compared to neutral stimuli. On the neural level, ADP displayed enhanced BOLD activity relative to HC during successful response inhibition in several areas involved in visual processing, cognitive and impulse control, including occipital structures, anterior cingulate gyrus, medial frontal gyrus and medial orbitofrontal cortex. CONCLUSIONS: We interpret these findings as a possible compensation strategy for impaired cognitive processing. Furthermore, the results underline the impact of salience of alcohol-related stimuli on response inhibition, which seems to affect both ADP and HC.

The impact of cognitive impairment and impulsivity on relapse of alcohol-dependent patients: implications for psychotherapeutic treatment.

Recent models of the development of addiction propose a transition from a pleasure-driven to a heavily automatized behaviour, marked by a loss of cognitive control. This study investigated the deficits in different components of cognitive functions including behavioural inhibition in response to alcohol-related stimuli in alcohol-dependent patients (ADP) and healthy controls (HC). The aims of the study were to identify which particular cognitive functions are impaired in ADP. Furthermore, we analysed the association between cognitive deficits and relapse rates and the reversibility of cognitive deficits under abstinence in a 6-month follow-up period. Ninety-four recently detoxified ADP and 71 HC completed the cognitive tasks as well as questionnaire measures assessing drinking behaviour and personality traits. Compared with HC, ADP showed poorer performance in response initiation, response inhibition, complex-sustained attention and executive functions. Impairment in response inhibition was a significant predictor for relapse, yet the strongest predictor was the interaction between the number of previous detoxifications and response-inhibition deficits. The results of a moderation analysis showed that patients with many previous detoxifications and large deficits in response inhibition showed the highest relapse risk. These findings indicate that interventions should take into account inhibitory deficits especially in ADP with a high number of previous detoxifications.

Is binge drinking in young adults associated with an alcohol-specific impairment of response inhibition?

BACKGROUND/AIMS: Little is known about the association of binge drinking with impulsivity related to trait- or state-like aspects of behavior. The aim of the present study was therefore to investigate whether binge drinkers show an impairment of inhibitory control in comparison to non-binge drinkers when confronted with alcohol-associated or control stimuli, and whether this is reflected in self-reported impulsivity. METHODS: A go/no-go task with pictures of alcoholic and nonalcoholic beverages as well as control stimuli was administered to binge drinkers and a gender-matched group of non-binge drinkers. All participants also completed the Barratt Impulsiveness Scale (BIS-11). RESULTS: We found an alcohol-specific impairment of response inhibition for binge drinkers only, while the groups did not differ with regard to overall response inhibition to the experimental stimuli or self-reported impulsiveness (BIS-11). In addition, the number of commission errors in response to alcohol-associated stimuli was the only significant predictor of binge drinking. CONCLUSION: The findings of the present study suggest that when young adults have established binge drinking as a common drinking pattern, impairment of inhibition in response to alcoholic stimuli is the only significant predictor of binge drinking, but not general impulsive behavior.