Mice navigate scent trails using predictive policies

Area of Science:

• Neuroscience
• Animal Behavior
• Sensory Systems

Background:

• Animals actively sense their environment to guide behaviors, with olfaction being key for mammals.
• Mice use active sniffing and orofacial orientation to sample odors for navigation.

Purpose of the Study:

• To investigate the strategies mice employ for navigating surface-bound odor trails.
• To understand the neural and behavioral mechanisms underlying odor-guided navigation in mice.

Main Methods:

• Utilized a paper treadmill to present dynamic, non-repeating odor trails to mice.
• Employed high-speed videography and quantitative behavioral analysis.
• Investigated the effects of unilateral nostril blockage and anterior commissure transection on trail tracking.

Main Results:

• Mice demonstrated rapid learning and precise, persistent tracking of odor trails.
• Unilateral nostril blockage resulted in lateral bias and reduced tracking precision.
• Anterior commissure transection severely impaired tracking and abolished the rapid turning response to sniffs near the trail.
• Trail tracking involves short-term memory of trail geometry and statistics, not just reactive behavior.

Conclusions:

• Mice combine immediate sensory input with an internal environmental model for efficient odor trail following.
• Interhemispheric communication is essential for precise, bilateral odor-guided navigation in mice.
• Odor-guided navigation relies on a sophisticated interplay between sensory processing, motor control, and cognitive strategies.