Multi-region recordings reveal collapse of hippocampal CA3-amygdala gamma communication at seizure onset in mice

Gamma CA3→amygdala directed coupling collapses abruptly at seizure onset in pilocarpine-induced temporal lobe seizures in awake mice, without a preceding decline.

• Why it matters: Mesial temporal lobe epilepsy involves coordinated limbic dysfunction, but how directed information flow reorganizes during the seizure transition is unresolved.
• What they did: Using a thermally drawn multifunctional fiber probe, the study recorded amygdala, hippocampal CA1/CA3, and cortex simultaneously in awake mice, then applied seizure-state classification and phase transfer entropy across seizure onset.
• The result: Pre-seizure gamma CA3→amygdala coupling co-occurred with reciprocal theta amygdala→CA3 coupling, while theta directional asymmetry reversed and gamma amygdala→cortex coupling increased at onset.