Joint modulation of neocortical electrical activity by nicotinic and muscarinic receptors.

A combination of subthreshold doses of nicotinic and muscarinic antagonist induced an increase in all the spectral components. The spectral amplitude change induced by a large scopolamine dose could not be augmented by either mecamylamine or an additional injection of scopolamine. NB lesions increased frontal slow wave activity (delta and theta amplitudes). Single or combined injections of scopolamine and mecamylamine produced a significantly smaller change in the frontal EEG amplitude values of NB-lesioned rats than in controls.