Post-mortem determinations of muscarinic cholinergic receptor parameters by means of binding procedures were carried out in human brains. In patients who died from internal capsule stroke a significant increase in cortical (Brodmann area 8) muscarinic receptor density was present when compared to non-neurological controls. No significant changes were detected in cortical choline acetyltransferase. Subcortical structures such as thalamus and caudate nucleus seemed to undergo opposite effects. It is suggested that acute interruption of fibers ascending to the cortex from subcortical areas can alter muscarinic receptor properties in the cerebral cortex.