How the connection between thinking, memory, and emotion areas relates to brain changes in antidepressant response

Chemogenetic activation of the infralimbic cortex induces rapid antidepressant-like effects in a mouse model of stress-induced depression.

• Activation of the infralimbic cortex enhances structural plasticity in the hippocampus.
• Restoration of long-term potentiation deficits occurs following infralimbic cortex stimulation.
• The thalamic nucleus reuniens is identified as a necessary mediator for these effects.
• Inhibition of the nucleus reuniens or its pathways blocks both the antidepressant response and neuroplastic effects associated with infralimbic cortex stimulation and ketamine treatment.
• The infralimbic cortex to nucleus reuniens to ventral hippocampus circuit is crucial for linking circuit activity, hippocampal plasticity, and depressive-like behaviors.

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