Audio-visual experience strengthens multisensory assemblies in adult mouse visual cortex.

Area of Science:

• Neuroscience
• Sensory processing
• Cortical plasticity

Background:

• The brain integrates information from multiple senses simultaneously.
• Understanding how different sensory inputs interact and shape neural circuits is crucial for comprehending brain function.

Purpose of the Study:

• To investigate if auditory and visual sensory inputs can interact and induce plasticity in the primary visual cortex (V1).
• To explore the mechanisms of multisensory integration within the visual cortex.

Main Methods:

• Utilized genetically-encoded voltage and calcium indicators in mouse models.
• Recorded neural activity in layer 2/3 (L2/3) of the primary visual cortex (V1).
• Administered paired audio-visual stimuli to assess neural response modifications.

Main Results:

• Coincident audio-visual experiences altered both supra- and subthreshold response properties of V1 neurons.
• A subset of multimodal neurons exhibited enhanced auditory responses after audio-visual pairing.
• This cross-modal plasticity was sustained for several days and involved strengthening functional networks of L2/3 neurons.

Conclusions:

• The primary visual cortex (V1) processes coincident auditory and visual events by strengthening functional associations between neuronal assemblies.
• Multisensory experiences leave a lasting trace in the cortical network, highlighting V1's role in integrating sensory information.