Auditory sensory processing induces cortical and thalamic event-related desynchronization in the mouse

Area of Science:

• Neuroscience
• Cognitive Science
• Electrophysiology

Background:

• Human perception involves early sensory encoding and later higher-order processing.
• Cortical event-related desynchronization (ERD) in alpha/beta bands is a key late signal linked to perceptual awareness.
• A suitable animal model is needed for detailed mechanistic investigation of ERD.

Purpose of the Study:

• To investigate the presence and characteristics of event-related desynchronization (ERD) in the mouse brain.
• To assess the mouse as an animal model for studying perceptual awareness.
• To compare early gamma activity and late alpha/beta ERD in different brain regions.

Main Methods:

• Local field potential recordings were performed in mouse frontal association cortex (FrA), thalamic centrolateral nucleus (CL), primary auditory cortex (A1), and primary visual cortex (V1).
• Two auditory tasks involving brief auditory stimuli were used.
• Analysis focused on early broadband gamma activity (30-100 Hz) and late alpha/beta ERD (8-12 Hz, 12-30 Hz).

Main Results:

• Auditory stimuli elicited early gamma activity followed by a late alpha/beta ERD in mouse FrA and A1, and thalamic CL.
• ERD was statistically significant in FrA and A1, but not V1.
• The magnitude and intensity-response slope of ERD were greatest in FrA, while early gamma activity was most pronounced in A1.

Conclusions:

• Mice demonstrate an ERD phenomenon analogous to humans, validating their use as a model for studying perceptual awareness.
• The mouse brain, particularly the FrA, shows distinct patterns of ERD and early gamma activity, offering insights into their neural origins and functions.
• This study provides a foundation for further research into the understudied electrophysiological phenomenon of ERD.