Authors:

Abstract

[Pharmacology of Implicit Memory]

Belonging to both neurosciences and cognitive sciences, the pharmacology of implicit memory is new. Likewise neurological and psychiatric conditions, drugs can specifically impair some forms of explicit and/or implicit memory, and spare others. For instance, diazepam, a benzodiazepine, and alcohol impair explicit memory, but not repetition priming, therefore inducing a pharmacological dissociation between the two forms of memory. In contrast lorazepam, another benzodiazepine, impairs both explicit memory and repetition priming; this probably holds true for scopolamine, an anticholinergic agent. This indicates that benzodiazepines have differential amnestic effects. Chlorpromazine, a neuroleptic, disturbs some forms of procedural memory, but leaves intact explicit memory and repetition priming. Lorazepam induces an opposite profile of memory dysfunction. Therefore, chlorpromazine and lorazepam provoke a double dissociation between repetition priming and procedural memory. Taken together, these findings suggest that explicit memory and the various forms of implicit memory rely upon memory systems which are psychobiologically distinct. They indicate that pharmacological approaches, using drugs as tools for investigating cognition, should not only based on the search for dissociations, but could be developed according to new kinds of logic, such as that aimed at determining the psychobiological and cognitive processes wich are specifically impaired by drugs.