Fictive vocalization in the cat.

A new animal model is described for the study of fictive vocalization, evoked by electrical stimulation of the periaqueductal grey (PAG) in decerebrate, paralyzed and artificially ventilated cats. Changes in activities of the phrenic, abdominal, recurrent and superior laryngeal nerves induced by PAG stimulation after induction of paralysis were compared with the activities of these nerves or the muscles innervated by them during actual vocalization induced before paralysis. The PAG-induced respiratory and laryngeal motor pattern in paralyzed cats is similar to that of PAG-induced vocalization. Furthermore, the switch from inspiration to vocal-like activity is usually synchronized with lung inflation in both paradigms. It is concluded that fictive vocalization can be induced by PAG stimulation in paralyzed cats.