Task-induced modulations of neuronal activity along the auditory pathway

Area of Science:

• Neuroscience
• Auditory Neuroscience

Background:

• Sensory processing is context-dependent.
• Understanding how behavioral context modulates neural activity is crucial.

Purpose of the Study:

• To investigate how task engagement modulates neuronal activity in the auditory system.
• To compare neuronal responses during passive hearing versus active listening in a tone-detection task.

Main Methods:

• Electrophysiological extracellular recordings were performed in mice across auditory pathway regions: inferior colliculus, medial geniculate body, primary auditory cortex, and anterior auditory field.
• Mice were trained in a tone-detection task.
• Clustering analysis was used to identify distinct patterns of neuronal modulation.

Main Results:

• Widespread neuronal modulations were observed across all auditory regions and cortical layers in both regular- and fast-spiking neurons.
• Ten distinct modulation patterns were identified, either enhancing or suppressing neuronal activity.
• Task engagement altered tone-onset responses in most neurons, with modulations emerging first in subcortical areas.
• Late modulations, linked to licking, arousal, or reward, were observed in half the neurons.

Conclusions:

• Auditory system neurons exhibit context-dependent modulation during active listening.
• Subcortical modulation is not solely driven by cortical feedback.
• Functionally distinct neuronal subclasses exist within the auditory pathway, showing differential sensitivity to task-related variables.