Auditory input enhances somatosensory encoding and tactile goal-directed behavior

The capacity of the brain to encode multiple types of sensory input is key to survival. Yet, how neurons integrate information from multiple sensory pathways and to what extent this influences behavior is largely unknown. Using two-photon Ca2+ imaging, optogenetics and electrophysiology in vivo and in vitro, we report the influence of auditory input on sensory encoding in the somatosensory cortex and show its impact on goal-directed behavior. Monosynaptic input from the auditory cortex enhanced dendritic and somatic encoding of tactile stimulation in layer 2/3 (L2/3), but not layer 5 (L5), pyramidal neurons in forepaw somatosensory cortex (S1). During a tactile-based goal-directed task, auditory input increased dendritic activity and reduced reaction time, which was abolished by photoinhibition of auditory cortex projections to forepaw S1. Taken together, these results indicate that dendrites of L2/3 pyramidal neurons encode multisensory information, leading to enhanced neuronal output and reduced response latency during goal-directed behavior. Multi-sensory input can lead to dendritic integration at the single neuron level. Here the authors show that combined auditory and somatosensory input increases distal dendritic and somatic activity in layer 2/3 pyramidal neurons of the primary somatosensory cortex and decreases response latency during somatosensory-based goal-directed behaviour.

Automated summary

The study demonstrates the impact of auditory input on sensory encoding in the somatosensory cortex and its positive influence on goal-directed behavior. Auditory input enhances neuronal output and reduces response latency during goal-directed behavior in a tactile-based task.