Perseveration and rotational behavior elicited by d-amphetamine in a Y-maze exploratory task: differential effects of intraperitoneal and unilateral intraventricular administration.

Mice received either intraperitoneal (1.0, 3.0, 5.0, or 15.0 mg/kg) or unilateral intraventricular injection (50.0, 100.0 or 200.0 microgram) of d-amphetamine. Both routes of injection produced circling behavior in a dose-related fashion when animals were tested in a circular alley-way. In contrast, performance in a free running Y-maze alternation task was differentially affected by the route of administration. Whereas intraperitoneal injection induced perseveration (i.e., animals consecutively visited only two arms of the maze), intraventricular injection augmented alternation behavior normally seen in saline-treated mice. It was suggested that Y-maze performance following intraventricular d-amphetamine injection reflects response perseveration, whereas systemic d-amphetamine treatment produced stimulus perseveration (repetition of location rather than direction). Moreover d-amphetamine-induced circling produced by intraperitoneal administration probably is an artifact of drug-induced stimulus perseveration as opposed to motor biases observed following intraventricular injections.