Oneiric behavior in cats]

The bilateral lesion of the medial portion of the nucleus Locus Coeruleus α or of its descending pathway selectively suppresses the muscular atonia during Paradoxical Sleep (PS) in the cat. After such a lesion various stereotyped behaviors (oneiric behavior) occur during PS. The repertoire of the oneiric behavior is described. It corresponds to the natural behavior which may occur during waking (predatory attack, rage, flight, grooming, exploration). Attack is the most frequent behavior occurring during PS while sexual behavior was never noticed. The significance of oneiric behavior is discussed and compared with natural, electrically induced behavior and play.