An increase in dendritic plateau potentials is associated with experience-dependent cortical map reorganization

Area of Science:

• Neuroscience
• Cortical Plasticity
• Sensory Map Organization

Background:

• Cortical sensory map organization relies on experience-driven synaptic plasticity.
• The posterior medial thalamic nucleus (POm) influences plasticity in the primary somatosensory cortex (S1) via disinhibition and dendritic plateau potentials.

Purpose of the Study:

• To investigate the role of thalamocortically mediated responses in whisker map plasticity in S1.
• To determine if POm-driven plateau potentials contribute to experience-dependent changes in sensory representations.

Main Methods:

• Whisker trimming in mice to alter sensory input.
• Electrophysiological recordings in S1 to measure neural activity.
• Pharmacological blockade of plateau potentials.

Main Results:

• Partial fusion of spared whisker representations observed after trimming.
• Increased occurrence of N-methyl-D-aspartate receptor-dependent plateau potentials driven by POm.
• Blocking plateau potentials restored the typical organization of the S1 whisker map.

Conclusions:

• Higher-order thalamocortical plateau potentials are a mechanism for experience-dependent cortical map plasticity.
• These potentials facilitate the fusion of segregated cortical representations based on sensory experience.