Persistent remembering and directed forgetting: Appraising emotional memory attenuation techniques

The permanent nature of memory has been a long-held axiom; under this axiom, memories were regarded as set entities that were invulnerable to disruption after a certain period of stabilization, referred to as consolidation, had passed. Challenging this view of memory, recent (and not-so-recent) empirical evidence suggests that under certain conditions, a previously consolidated memory trace can become active again and susceptible to modification for a limited time window. During this time, various post-reactivation manipulations can be applied with the intention to either update the memory trace or to disrupt its restabilization, commonly referred to as reconsolidation. Reconsolidation-based manipulations have thus presented novel opportunities for the attenuation of emotional memory expression. However, many of the seminal findings in the literature do not readily replicate. The aim of this project was to subject various techniques to attenuate experimentally-induced emotional memories in humans, and their underlying mechanisms, to a critical test. In the first part of the project, the effects of various post-reactivation manipulations on subsequent emotional memory expression were examined, namely, propranolol administration, extinction training, and the cognitive processing blockade approach. All three manipulations failed to attenuate emotional memory expression, yet we did detect an acute effect of propranolol on extinction performance (i.e., attenuated conditioned responding). Further, we discovered several problems and inconsistencies in the first report of experimental amnesia following post-reactivation extinction training in humans, thus explaining our failure to obtain the reported results after directly replicating this procedure. When examining the literature, one would believe that reconsolidation is a robust phenomenon that is observed across species and paradigms, but during this project we gathered extensive evidence against the presence of reconsolidation-based effects. In the second part of the project, directed forgetting, a procedure involving instructed forgetting of declarative information, was explored as a novel means of disrupting emotional memory expression. The manipulation we designed was consistently successful in disrupting declarative, verbal report and also resulted in the disruption of physiological conditioned responding, suggesting that directed forgetting manipulations can be applied to interfere with emotional memories.

Jaar van publicatie:2020

Toegankelijkheid:Open