Experience-dependent functional plasticity and visual response selectivity of surviving subplate neurons in the mouse...

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Visual System Research

Background:

• Subplate neurons are crucial for early cortical development but mostly undergo cell death.
• The functional properties of surviving subplate neurons, identified as layer 6b (L6b) neurons, remain largely uncharacterized.

Purpose of the Study:

• To investigate the visual response properties and experience-dependent plasticity of L6b neurons in the primary visual cortex (V1).
• To determine if L6b neurons, remnants of subplate neurons, exhibit functional plasticity similar to other cortical layers.

Main Methods:

• Two-photon calcium imaging in awake juvenile mice to record V1 neuronal activity.
• 3D immunohistochemistry to confirm L6b neuron identity using connective tissue growth factor (CTGF).
• Monocular deprivation experiments to assess ocular dominance (OD) plasticity.

Main Results:

• L6b neurons displayed broader visual tuning (orientation, direction, spatial frequency) and lower interocular orientation preference matching than L2/3 and L6a neurons.
• L6b neurons expressing CTGF demonstrated ocular dominance plasticity following monocular deprivation.
• The extent of OD shift was influenced by the neuron's pre-deprivation response strength, but plasticity occurred across various response selectivities.

Conclusions:

• Surviving subplate neurons (L6b neurons) possess distinct visual response characteristics.
• L6b neurons exhibit significant experience-dependent ocular dominance plasticity, even at later developmental stages.
• These findings highlight the continued functional relevance and plasticity of subplate neuron remnants in the mature visual cortex.