Inhibition of auditory cortical neurons during phonation

Area of Science:

• Neuroscience
• Auditory Neuroscience
• Primate Communication

Background:

• The auditory cortex processes sound, while phonation involves vocalization production.
• Understanding the interplay between auditory processing and vocalization is crucial for studying communication.

Purpose of the Study:

• To investigate the relationship between brain activity during vocalization (phonation) and auditory processing in squirrel monkeys.
• To explore neuronal mechanisms underlying audiovocal communication.

Main Methods:

• Extracellular recordings of single-cell activity in the auditory cortex (superior temporal gyrus) of squirrel monkeys.
• Stimulation using self-produced vocalizations (elicited or spontaneous) and recorded vocalizations.
• Comparison of neuronal responses during phonation versus playback of vocalizations.

Main Results:

• Over half of auditory cortex cells showed weaker or no response to self-produced vocalizations during phonation.
• A subset of neurons did not distinguish between self-produced and recorded vocalizations.
• Evidence suggests an inhibitory influence from phonation-related brain structures on the auditory cortex.

Conclusions:

• Phonation activates brain structures that inhibit parts of the auditory cortex.
• This suggests a neuronal feed-forward circuit mechanism in audiovocal communication.
• Findings contribute to understanding neural control of vocal communication in primates.