Dissociable contributions of the amygdala and ventral hippocampus to stress-induced changes in defensive behavior

• Published in: Cell reports (Cambridge) Vol. 43; no. 11; p. 114871
• Main Authors: Pennington, Zachary T., LaBanca, Alexa R., Sompolpong, Patlapa, Abdel-Raheim, Shereen D., Ko, Bumjin, Christenson Wick, Zoe, Feng, Yu, Dong, Zhe, Francisco, Taylor R., Bacon, Madeline E., Chen, Lingxuan, Fulton, Sasha L., Maze, Ian, Shuman, Tristan, Cai, Denise J.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 26-11-2024; Elsevier
• Subjects: Amygdala; anxiety; CP: Neuroscience; fear; hippocampus; non-associative learning; plasticity; sensitization; stress; stress-enhanced fear learning; trauma; trauma; stress; anxiety; stress-enhanced fear learning; Amygdala; hippocampus; CP: Neuroscience; non-associative learning; plasticity; sensitization; fear
• ISSN: 2211-1247; 2211-1247
• DOI: 10.1016/j.celrep.2024.114871

Stress can have profound consequences on mental health. While much is known about the neural circuits supporting associative memories of stressful events, our understanding of the circuits underlying the non-associative impacts of stress, such as heightened stress sensitivity and anxiety-related behavior, is limited. Here, we demonstrate that the ventral hippocampus (vHC) and basolateral amygdala (BLA) support distinct non-associative behavioral changes following stress. Inhibiting stress-induced protein synthesis in the BLA blocked subsequent increases in stress sensitivity but not anxiety-related behaviors. Conversely, inhibiting stress-induced protein synthesis in the vHC blocked subsequent increases in anxiety-related behavior but not stress sensitivity. Inhibiting neuronal activity in the BLA and vHC during the assessment of stress sensitivity or anxiety-related behavior recapitulated these structures’ dissociable contributions to defensive behavior. Lastly, blocking the associative memory of a stressor had no impact on stress-induced changes in anxiety-related behavior. These findings highlight that multiple memory systems support the long-lasting effects of stress.
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•Stress induces changes in both associative and non-associative defensive behaviors•Increases in stress sensitivity and anxiety-related behavior are non-associative•Basolateral amygdala (BLA) is required for heightened stress sensitivity•Ventral hippocampus (vHC) is required for increased anxiety-related behavior
Impacts of stressful life events are often attributed to memories of stress-associated cues. Pennington et al. demonstrate that increased anxiety-related behavior and sensitivity to novel stressors resulting from a stressful life event are independent of these memories. They find that the amygdala and hippocampus contribute differently to these behaviors.