Overgeneralization of autobiographical memory strategies in cannabis users and multiple psychoactive substance consumers

Objectives

Psychoactive substance consumption induces cognitive impairments in terms of episodic memory and attentional and executive function deficits. This study aims to investigate whether the recall of autobiographical memories is disturbed in substance consumers, and in particular whether those patients tend to evoke memories at a general level rather than at a specific level when confronted by an emotional cue word. Furthermore, we aim to verify whether adopting a more general memory retrieving style is a dynamic phenomenon and if it depends on the type of substance consumed.

Design and methods

The participants of this research were 51 cannabis users, including 17 occasional cannabis users, 17 cannabis abusers and 17 individuals addicted to cannabis. They were compared to 18 multiple substance-dependent individuals and to 38 nondependent individuals. Participants were subjected to the Williams and Scott (1988) [39] autobiographical memory test. After an assessment of the mode of substance consumption, several clinical dimensions were measured, such as depression (BDI), anxiety (STAI Y A and B), alexithymia (TAS 20) and episodic memory (RLS-15).

Results

The results show that the percentage of general positive and negative memories recalled increases progressively as the consumption takes on the characteristics of addictive behavior, while we observe no deficit in episodic memory. The level of alexithymia evolved in parallel with the percentage of general memories. These results are not dependent on the type of substance used and can not be explained by the level of depression.

Conclusions

Overgeneralization is a phenomenon observable in psychoactive substance consumers, whatever the type of substances used, which sets in progressively as the dependence develops. Our results show that overgeneralization is not only due to an impairment of mnesic abilities, implying that this phenomenon could be underlined by several mechanisms. The role of overgeneralization as a functional avoidance established in attempt to protect individuals from emotion resurgence is discussed. Furthermore, the impact of deficits in executive functions on the recall of autobiographical memories in substance abusers has not been studied and would be an interesting path of research.