Interrogating roles for VTA dopamine neurons in locomotion and ultrasonic vocalizations elicited by different classes of rewarding drugs.
Psychopharmacology July 14, 2026 Kate A Lawson, Stephen V Mahler
Rats can convey information about their internal states through ultrasonic vocalizations (USVs). In male and female TH:cre rats and wildtype littermates, amphetamine (2 mg/kg) elicited high-frequency USVs and increased locomotion, heroin (0.25 mg/kg) elicited low-frequency USVs in some rats without altering high-frequency USVs or locomotion, and ketamine (30 mg/kg) suppressed high-frequency USVs while transiently increasing locomotion. Chemogenetically inhibiting or stimulating ventral tegmental area dopamine neurons suppressed amphetamine- or ketamine-induced locomotion and amphetamine-induced USVs. USVs provide a behavioral readout of drug and brain manipulation effects that locomotion alone cannot capture, potentially helping bridge human and rodent neuroscience.