Auditory cortex modulates call duration in rats

TL;DR

The rat's auditory cortex directly influences the timing and duration of its vocalizations through specific types of neurons and chemical interventions.

Contribution

This study identifies distinct auditory cortex neuron classes and demonstrates their role in modulating vocal behavior in rats.

Findings

Five types of auditory cortical vocalization response neurons were identified in rats.

Pharmacological manipulation of the auditory cortex altered vocalization duration.

External noise stimulation mimicked the effects of GABA_A receptor antagonists on call duration.

Abstract

The flexibility of human vocal production is well studied, but the direct role of the auditory system in regulating vocalizations in rodents remains largely unexplored. We show that during vocalizations, a fraction of rat auditory cortex neurons shows pre-call activity and different patterns of responses during calls and playback of calls. Additionally, we classified five auditory cortical vocalization responses: pre-call activated, onset activated, onset suppressed, ramping activated and ramping suppressed neurons. Intriguingly, onset suppressed cells can predict vocalization duration and occurrence. Injecting the auditory cortex with muscimol (GABA_A receptor agonist) prolonged vocalizations, while injecting the auditory cortex with gabazine (GABA_A receptor antagonist) shortened them. Similar reductions in call duration were observed during external white-noise stimulation of the auditory cortex and/or other auditory brain structures, resembling the effects of gabazine. Together, neuronal recordings, pharmacological interference and noise induced vocal modifications indicate direct modulation of vocal productions by the rat auditory cortex.

Neuronal and pharmacological analysis of rat auditory cortex reveals its direct role in regulating vocal production, identifying distinct neuron classes that predict call timing and duration and demonstrating auditory modulation of vocal behavior

Figures