Vocalization after electrostimulation of the brain of pigeons in relation to heart- and breathing-rates.

Vocalizations elicited by electrical stimulation in the midbrain of pigeons were studied in connection with heart- and breathing-rates. Most of the sites where sound production could be elicited were found in the nucleus intercollicularis (ICo), lying rostromedial to the nucleus mesencephalicus lateralis, pars dorsalis (Mld). All vocalizations were accompanied by an increase of heart- and breathing-rates. Electrical stimulation elicits predominantly changes in breathing-rate which can be accompanied by passive vocalization.