Sequential discharges of phasic activities (PGO waves) during paradoxical sleep after selective cortical lesions in the cat.

We investigated the role that cortical areas have upon the sequences of PGO waves and associated phasic activity in the lateral rectus muscles of the eyes (PALRE) during PS. We performed several combined type of lesions (bilateral ablations of frontal lobes carried out in two sessions, or occipital lesions combined with bifrontla lobotomies). We used statistical methods previously described for the normal cat (4). We showed that frontal lesions need to be bilateral in order to be effective, that thereafter there is a recovery in the complexity of the patterns in the survival period. We showed that occipital lobectomies "per se" do not affect the PGO pattern, but their combination with bifrontal lobotomies produce the most dramatic changes which lasted throughout the survival period. These findings are discussed on the light of the well known anatomical cortical projections to brain stem structures which participate in the determinism of PGO waves during paradoxical sleep.