Infralimbic parvalbumin neural activity facilitates cued threat avoidance

Area of Science:

• Neuroscience
• Behavioral Neuroscience
• Molecular Psychiatry

Background:

• The infralimbic cortex (IL) plays a key role in flexible behavioral responses to threats.
• Understanding the specific roles of IL neural subtypes in avoidance behavior is crucial.
• Parvalbumin (PV) interneurons are a distinct subtype within the IL with poorly understood functions.

Purpose of the Study:

• To investigate the role of IL parvalbumin (PV) interneurons in active avoidance behavior.
• To determine how PV interneuron activity relates to suppressing freezing and enabling movement to safety.

Main Methods:

• Utilized a mouse model to study active avoidance behavior following a single shock.
• Recorded PV interneuron activity during avoidance, reward-seeking, and general locomotion tasks.
• Employed optogenetics to suppress PV neuron activity and assess behavioral changes.

Main Results:

• IL PV interneuron activity increased during movement to avoid shock, emerging after initial shock exposure.
• PV neuron activity did not change during reward-seeking or general locomotion.
• Optogenetic suppression of PV neurons prolonged freezing and delayed avoidance onset, without affecting other movements.

Conclusions:

• IL PV interneurons are critical for strategic avoidance behavior by actively suppressing freezing.
• These findings elucidate a specific neural mechanism underlying threat avoidance and behavioral flexibility.