Memory formation and retrieval of neuronal silencing in the auditory cortex

• DOI: 10.1073/pnas.1500869112
• Publication Date: 2015-07-22T02:10:15Z
• Authors: Hiroshi Nomura; Kojiro Hara; Reimi Abe; Natsuko Hitora-Im...; Ryota Nakayama; Takuya Sasaki; Norio Matsuki; Yuji Ikegaya
• Keywords: Auditory Cortex; Male; Neurons; 0303 health sciences; Light; Archaeal Proteins; Conditioning, Classical; Association Learning; Fear; Transfection; Mice, Inbred C57BL; Optogenetics; 03 medical and health sciences; Reward; Mental Recall; Animals; Freezing Reaction, Cataleptic

Significance Cortical neurons exhibit spontaneous activity without explicit external stimuli. Sensory stimuli not only activate specific populations of those neurons but can also silence other populations. However, it remains unclear whether neuronal silencing per se leads to memory formation and behavioral expression. Here, we used optogenetic silencing of a neuronal ensemble in the auditory cortex and found that mice exhibited a fear response to silencing that had been previously paired with footshock, and could find a reward based on the presence or absence of the silencing. These findings indicate that neuronal silencing per se, which is originally believed to be involved in neuronal modulation, is enough to elicit a cognitive behavior.