Asynchronous development of the mouse auditory cortex is driven by hemispheric identity and sex

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Auditory Neuroscience

Background:

• Lateralized auditory processing, crucial for speech, is typically left-dominant in humans.
• Hemispheric specializations exist in the mouse auditory cortex (ACx), but their developmental basis is unknown.

Purpose of the Study:

• Investigate the developmental origins of hemispheric specialization in the mouse auditory cortex.
• Determine how asynchronous development influences sensory-driven plasticity and functional outcomes.

Main Methods:

• Comparative analysis of developmental milestones in the Left and Right ACx.
• Assessment of thalamocortical responses and synaptic dynamics maturation timing.
• Evaluation of sensory-driven plasticity following juvenile tone exposure.
• Examination of sex-dependent differences in ACx plasticity timing.

Main Results:

• The Right ACx matures earlier than the Left ACx, with earlier thalamocortical response and synaptic dynamics maturation.
• Developmental timing differences predict hemisphere-specific sensory-driven plasticity.
• Juvenile auditory experience leads to imbalanced adult tone frequency representations between hemispheres.
• Sex influences plasticity timing, with females exhibiting earlier Right ACx plasticity than males.

Conclusions:

• Asynchronous development of the Left and Right ACx is driven by hemispheric identity and sex.
• These developmental asynchronies contribute to functional differences in sensory cortices.
• Understanding these differences is key to comprehending auditory processing and plasticity.