Plasticity of Local-Circuit Constraint Properties During Functional Reorganization of Adult Cortex Author: Paullus,
نویسندگان
چکیده
The primary somatosensory cortex (SI) is topographically organized into a map of the body. This organization is dynamic, undergoing experience-dependent modifications throughout life. It has been hypothesized that excitatory and inhibitory synaptic plasticity of horizontal intracortical connections contributes to functional reorganization. However, very little is known about synaptic plasticity of these connections; particularly the characteristics of inhibitory synaptic plasticity, its relationship to excitatory synaptic plasticity, and their relationship to the functional organization of the cortex. To investigate this, I located the border between the somatosensory forepaw and lower jaw representation in vivo, and used whole cell-patch electrophysiology to record postsynaptic excitatory and inhibitory currents (EPSCs and IPSCs) of supragranular polysynaptic horizontal connections in vitro. Connections that remained within the representation (continuous) and those that crossed from one representation to another (discontinuous) were stimulated differentially, allowing us to examine differences associated with the border. To induce synaptic plasticity, tetanic stimulation was applied to either continuous or discontinuous pathways. Tetanic stimulation induced diverse
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