Face your fears: attenuating remote fear memories by reconsolidation-updating

• Published in: Trends in cognitive sciences Vol. 27; no. 4; pp. 404 - 416
• Main Authors: Silva, Bianca A., Gräff, Johannes
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.04.2023
• Subjects: Animals; extinction; Extinction, Psychological - physiology; fear; Fear - physiology; Humans; Memory - physiology; Memory, Long-Term; Neuronal Plasticity; plasticity; reconsolidation; remote memory; trauma; updating; trauma; remote memory; updating; extinction; plasticity; reconsolidation; fear
• ISSN: 1364-6613; 1879-307X
• DOI: 10.1016/j.tics.2023.01.004

Despite an inherent resistance to be changed, remote fear memories can be attenuated by reconsolidation-updating approaches.Reconsolidation-updating capitalizes on an etiologically relevant period of memory malleability induced by recall, which is characterized by elevated levels of neuronal plasticity.Such neuronal plasticity helps fearful memories to be updated toward safety, which has been evidenced at the level of fear circuits, engrams, and molecular changes.Therefore, treatments aimed at fostering this plasticity constitute a promising approach to support reconsolidation-updating for permanently changing remote fear memories. Traumatic events generate some of the most enduring memories, yet little is known about how long-lasting fear memories can be attenuated. In this review, we collect the surprisingly sparse evidence on remote fear memory attenuation from both animal and human research. What is becoming apparent is twofold: although remote fear memories are more resistant to change compared with recent ones, they can nevertheless be attenuated when interventions are targeted toward the period of memory malleability instigated by memory recall, the reconsolidation window. We describe the physiological mechanisms underlying remote reconsolidation-updating approaches and highlight how they can be enhanced through interventions promoting synaptic plasticity. By capitalizing on an intrinsically relevant phase of memory, reconsolidation-updating harbors the potential to permanently alter remote fear memories.