Orbitofrontal cortex modulates auditory cortical sensitivity and sound perception in Mongolian gerbils

Area of Science:

• Neuroscience
• Auditory Perception
• Sensory Processing

Background:

• Sensory perception dynamically adapts to environmental and behavioral context shifts.
• Rapid fluctuations in sensory cortical activity mediate these dynamics, but orchestrating brain regions remain unclear.
• Orbitofrontal cortex (OFC) neurons encode context, with some signals projecting to sensory cortices.

Purpose of the Study:

• To investigate if the OFC mediates context-dependent changes in auditory cortical sensitivity and sound perception.
• To monitor and manipulate OFC activity during different behavioral contexts.

Main Methods:

• Monitoring and manipulating orbitofrontal cortex (OFC) neural activity in freely moving Mongolian gerbils.
• Utilizing passive sound exposure and an amplitude modulation (AM) detection task as behavioral contexts.
• Employing pharmacological inactivation of the OFC.

Main Results:

• A majority of OFC neurons, including those projecting to the auditory cortex, were modulated by task engagement.
• OFC inactivation prevented context-dependent auditory cortical firing changes and impaired AM detection behavior.
• OFC activity is essential for rapid auditory cortex plasticity.

Conclusions:

• The orbitofrontal cortex (OFC) plays a critical role in mediating rapid plasticity within the auditory cortex.
• OFC signals facilitate the perception of behaviorally relevant sounds by adjusting auditory sensitivity based on context.
• This research elucidates a key pathway for context-dependent sensory processing.