The role of GABA A in the expression of updated information through the reconsolidation process in humans

Abstract

Consolidated memory can be again destabilized by the presentation of a memory cue (reminder) of the previously acquired information. During this process of labilization/restabilization memory traces can be either impaired, strengthened or updated in content. Here, we study if a consolidated memory can be updated by linking one original cue to two different outcomes and whether this process was modulated by the GABAergic system. To aim that, we designed two experiments carried out in three consecutive days. All participants learned a list of non-sense syllable pairs on day 1. On day 2 the new information was introduced after the reminder or no-reminder presentation. Participants were tested on day 3 for the updated or original list (Exp. 1). In Exp. 2 we tested whether this new information was incorporated by an inhibitory process mediated by the GABAergic system. For that, participants retrieved the original information before being taken Clonazepam 0.25mg (GABA agonist) or Placebo pill. We found that the groups that received the reminder correctly recalled the old and new information. However, the no reminder groups only correctly recalled the original information. Furthermore, when testing occurred in the presence of Clonazepam, the group that received the reminder plus the new information showed an impaired original memory performance compared to the group that received only Clonazepam (without reminder) or the reminder plus Placebo pill. These results show that new information can be added to a reactivated declarative memory in humans by linking one cue to two different outcomes. Furthermore, we shed light on the mechanisms of memory updating being the GABAergic system involved in the modulation of the old and new information expression.

A reappraisal of acute doses of benzodiazepines as a model of anterograde amnesia

“…Acute BZs effects may aid in this respect, but we have no data to compare our results with. Prior studies in humans only administered these drugs after reactivation (Fernández et al, 2017;Rodríguez et al, 2013) and did not test changes in reactivated memories under their effects, as done here.…”

“…H. Walsh, Das, Saladin, & Kamboj, 2018), especially in animal studies (Makkar, Zhang, & Cranney, 2010). However, this has not been studied in human participants, in whom BZs have only been administered after reminder presentation (reactivation; e.g., Fernández, Moyano, Radloff, Campos, Allegri, 2017;Rodríguez et al, 2013).…”

Non-linear susceptibility to interferences in declarative memory formation

“…Subjects that reached at least 55% of correct responses during the last four training trials (11/20 correct responses) were included in the analysis [ 21 ]. 77 subjects were excluded from the analysis because they did not reach the learning criterion (43), did not followed/understand the instructions of the task (16), wrote the syllables in a piece of paper during the training session or the retention interval (10), used psychopharmaceuticals that they had not reported it the initial interview (4), slept a nap during retention interval (1), did not accomplished the schedule for carry out the experiment (2) or technical problems (1).…”