Autobiographical memory and differentiation of schematic models in substance-dependent patients

This study aims at investigating reduced autobiographical memory specificity in substance-dependent patients. We examined whether this phenomenon is related to undifferentiated schematic models of self and to depression and anxiety levels. We also investigated the maintenance of these impairments after early clinical remission.

Seventy-three dependent patients (including 30 active users, 23 methadone-maintained patients, 20 early abstinent patients) and 31 control participants were given Williams' and Scott's Autobiographical Memory Test (AMT) to evaluate the level of memory specificity. Depression and anxiety levels were assessed with the Hospital Anxiety and Depression Scale (HADS), and the ability of differentiation in affect-related schematic models of self with the Level of Emotional Awareness Scale (LEAS).

Dependent patients recall less specific memories than control individuals to the AMT. For all the participants, only the ability to differentiate emotional states predicts the level of specificity, whereas reduced specificity is not linked to depression and anxiety levels. The results also show that reduced specificity is still observable in methadone-maintained patients and in abstinent patients.

Despite the absence of difference in the level of memory specificity in the three groups of dependent patients, we cannot state that reduced memory specificity is stable over time because non-active consumers may not remain in remission for a long period.

Only a lack of emotional differentiation seems to impede the access to specific memories in dependent patients and in general population. The reduced memory specificity observed in dependent patients seems to last after recent clinical improvement.