Retrieving fear memories, as time goes by

• Published in: Molecular psychiatry Vol. 21; no. 8; pp. 1027 - 1036
• Main Authors: Do Monte, F H, Quirk, G J, Li, B, Penzo, M A
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.08.2016; Nature Publishing Group
• Subjects: 13/51; 14/34; 631/1647; 64/110; 64/60; 9/74; 96/63; Amygdala - metabolism; Analysis; Animals; Auditory pathways; Behavioral Sciences; Biological Psychology; Brain research; Brain-Derived Neurotrophic Factor - metabolism; Central Amygdaloid Nucleus - physiology; Conditioning, Classical - physiology; Design; Fear - physiology; Fear conditioning; Humans; Laboratory animals; Medicine; Medicine & Public Health; Memory - physiology; Memory, Long-Term - physiology; Mental health; Midline Thalamic Nuclei - physiology; Neural Pathways - physiology; Neurobiology; Neurons; Neurosciences; Paraventricular nucleus; Pharmacotherapy; Psychiatry; review; Stimuli (Psychology); Thalamus; Thalamus - physiology; United States > US; Puerto Rico
• ISSN: 1359-4184; 1476-5578
• DOI: 10.1038/mp.2016.78

Research in fear conditioning has provided a comprehensive picture of the neuronal circuit underlying the formation of fear memories. In contrast, our understanding of the retrieval of fear memories is much more limited. This disparity may stem from the fact that fear memories are not rigid, but reorganize over time. To bring some clarity and raise awareness about the time-dependent dynamics of retrieval circuits, we review current evidence on the neuronal circuitry participating in fear memory retrieval at both early and late time points following auditory fear conditioning. We focus on the temporal recruitment of the paraventricular nucleus of the thalamus (PVT) for the retrieval and maintenance of fear memories. Finally, we speculate as to why retrieval circuits change with time, and consider the functional strategy of recruiting structures not previously considered as part of the retrieval circuit.