Neuronal activity in the human amygdala and hippocampus enhances emotional memory encoding

Nat Hum Behav. 2023 May;7(5):754-764. doi: 10.1038/s41562-022-01502-8. Epub 2023 Jan 16.


Emotional events comprise our strongest and most valuable memories. Here we examined how the brain prioritizes emotional information for storage using direct brain recording and deep brain stimulation. First, 148 participants undergoing intracranial electroencephalographic (iEEG) recording performed an episodic memory task. Participants were most successful at remembering emotionally arousing stimuli. High-frequency activity (HFA), a correlate of neuronal spiking activity, increased in both the hippocampus and the amygdala when participants successfully encoded emotional stimuli. Next, in a subset of participants (N = 19), we show that applying high-frequency electrical stimulation to the hippocampus selectively diminished memory for emotional stimuli and specifically decreased HFA. Finally, we show that individuals with depression (N = 19) also exhibit diminished emotion-mediated memory and HFA. By demonstrating how direct stimulation and symptoms of depression unlink HFA, emotion and memory, we show the causal and translational potential of neural activity in the amygdalohippocampal circuit for prioritizing emotionally arousing memories.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amygdala / diagnostic imaging
  • Amygdala / physiology
  • Brain
  • Emotions* / physiology
  • Hippocampus / physiology
  • Humans
  • Mental Recall* / physiology