Summary
An experimental study has been made of the afferent connections of the motor cortex of the monkey from the thalamus, contralateral motor cortex and ipsilateral somatic sensory and pre-motor areas using the electron microscope. The terminals from all these sites have asymmetric membrane specializations. The majority of the terminals from each site end on dendritic spines, probably of pyramidal cells, and a proportion end on the dendrites or somata of large stellate cells. The different laminar terminations are described and it was found that the thalamo-cortical terminals are also related to bundles of apical dendrites in the main laminae of their termination.
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Sloper, J.J. An electron microscope study of the termination of afferent connections to the primate motor cortex. J Neurocytol 2, 361–368 (1973). https://doi.org/10.1007/BF01103794
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DOI: https://doi.org/10.1007/BF01103794