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bioRxiv · 10.1101/2020.01.08.898643

A working memory intervention weakens the reconsolidation of a threat memory and its biases processing towards threat.

Abstract

BACKGROUNDThreat-conditioning (TC) memory plays a central role in anxiety disorders, but not in a simple way. This memory impacts on complex cognitive systems by modifying behavioral responses with a bias to fearful stimuli and overestimating potential threats. In this study we proposed a global approach analyzing the scope of disrupting TC memory reconsolidation in the implicit memory, the declarative contingency and the cognitive biases. METHODSDay 1: Subjects were trained on TC. Day 2: after Threat-memory reactivation, one group performed a high demanding working memory task (HWM) and the other a low demanding working memory task (LWM). The last group, only performed the HWM task. Day 3: TC memory was tested by an extinction session followed by reinstatement. Finally, all subjects completed tasks targeting stimuli representation, valuation and attentional bias towards threat. RESULTSDisrupting reconsolidation of TC memory with a HWM weakened the implicit memory retention and faded the representation and valuation towards threat but it had no effect on attentional bias. Moreover, we revealed that subjects performance during the working memory task was specifically associated in TC memory retention. CONCLUSIONSOur findings reveal a strong impairment of the threat-memory restabilization and associated emotional biases. This may result from the competition between defensive survival and central-executive control networks. Our results fits with Experimental Psychopathology approach, disentangling the relation between the implicit memory, cognitive, valenced systems and the possibility to weaken both the threatening memory and the systems associated with the maintenance of anxiety profile.

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Picco, S., Bavassi, L., Fernandez, R. S., Pedreira, M. E.. 2020-01-09. A working memory intervention weakens the reconsolidation of a threat memory and its biases processing towards threat.. https://doi.org/10.1101/2020.01.08.898643

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