# Behavioral engagement facilitates auditory neuron responses beyond their receptive fields

## TL;DR

This study shows that focusing on sound locations can boost brain cell activity beyond their usual response areas in marmosets.

## Contribution

The study reveals task-driven neural facilitation beyond receptive fields in auditory cortex, with spatial and regional specificity.

## Key findings

- Task engagement increases firing rates both within and outside receptive fields in auditory neurons.
- Off-RF facilitation was more common in the caudal area compared to rostral and primary auditory cortex.
- A normalization model with widespread suppression successfully predicted the observed off-RF facilitation.

## Abstract

In the auditory cortex, neural responses to stimuli inside receptive fields (RFs) can be further facilitated by behavioral demands, such as attending to a spatial location. It is less clear how off-RF stimuli modulate neural responses and contribute to behavioral tasks. Our recent study revealed a particular form of location-specific facilitation evoked by repeated stimulation from an off-RF location, suggesting behavioral modulation of spatial RFs. To further explore this question, we trained marmosets to attend to sound locations that were either inside or outside the RFs of auditory cortical neurons. The majority of neurons showed increased firing rates at target locations inside their RFs. Interestingly, this increase also occurred outside the RFs, sometimes exceeding the responses at the RF center during passive listening. This task-related off-RF facilitation was much more common in the caudal area than in the rostral area and the primary auditory cortex. A normalization model reproduced the off-RF facilitation using widespread suppression. The model’s prediction was confirmed by experimental observations of widespread reductions in firing rate and hyperpolarized membrane potentials for off-RF stimuli. These results suggest that behavioral task demands recruit a broader range of neurons than those that are responsive to a target sound in the passive state.

During passive listening, auditory cortical neurons typically respond only to stimuli within a particular receptive field, but repeated stimulation can facilitate responses to non-preferred locations. This study in marmosets shows that task engagement facilitates neuronal responses both within and beyond their receptive fields, reallocating limited neural resources to the most informative locations.