Light tunes long-term threat avoidance behavior in male mice

Area of Science:

• Neuroscience
• Behavioral Biology
• Vision Science

Background:

• Animals require continuous environmental monitoring for safety and must integrate past experiences to predict future threats.
• Visual input is crucial for threat detection, but its role in shaping long-term threat assessment based on prior experience remains unclear.

Purpose of the Study:

• To develop and characterize a behavioral assay for long-term threat avoidance learning.
• To investigate the neural mechanisms, particularly the role of specific retinal cell types and brain circuits, underlying this learned avoidance behavior in male mice.

Main Methods:

• Development of a novel behavioral paradigm to assess long-term threat avoidance after single threat exposure.
• Utilizing male mice to study the role of melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs).
• Investigating the involvement of the perihabenula-nucleus accumbens circuit in modulating threat avoidance.

Main Results:

• A sensitive, multi-day long-term threat avoidance behavior was established, where animals avoid locations associated with past threats.
• Melanopsin-expressing ipRGCs were found to significantly tune this long-term avoidance behavior.
• The perihabenula-nucleus accumbens pathway was identified as a key circuit, distinct from canonical threat detection pathways, mediating this learned behavior.

Conclusions:

• This study defines a novel long-term threat avoidance behavior in mice.
• Melanopsin-expressing ipRGCs play a critical role in shaping learned threat avoidance based on prior experience.
• A distinct neural circuit involving the perihabenula and nucleus accumbens mediates this experience-dependent visual threat memory.