Impaired conditional reasoning in alcoholics: a negative impact on social interactions and risky behaviors?


Charles Kornreich, CHU Brugmann, Psychiatric Institute, Place Van Gehuchten 4, 1020 Brussels, Belgium. E-mail:


Aims  To study the ‘social brain’ in alcoholics by investigating social contract reasoning, theory of mind and emotional intelligence.

Design  A behavioral study comparing recently detoxified alcoholics with normal, healthy controls.

Setting  Emotional intelligence and decoding of emotional non-verbal cues have been shown to be impaired in alcoholics. This study explores whether these deficits extend to conditional reasoning about social contracts.

Participants  Twenty-five recently detoxified alcoholics (17 men and eight women) were compared with 25 normal controls (17 men and eight women) matched for sex, age and education level.

Measurements  Wason selection task investigating conditional reasoning on three different rule types (social contract, precautionary and descriptive), revised Reading the Mind in the Eyes Test, Trait Emotional Intelligence Questionnaire (modified version) and additional control measures.

Findings  Conditional reasoning was impaired in alcoholics. Performance on descriptive rules was not above chance. Reasoning performance was markedly better on social contract and precautionary rules, but this performance was still significantly lower than in controls. Several emotional intelligence measures were lower in alcoholics compared to controls, but these were not correlated with reasoning performance.

Conclusions  Conditional reasoning, including reasoning about social contracts and emotional intelligence appear to be impaired in alcoholics. Impairment seems to be particularly severe on descriptive rules. Impairment in social contract reasoning might lead to misunderstandings and frustration in social interactions, and reasoning difficulties about precautionary rules might contribute to risky behaviors in this population.