Sudden Death Revisited: Regression Of Stereotypies Into A Behavioral Trap

Abstract

Rats were injected with 20 mg/kg of d-amphetamine sulfate to elicit stereotypic stages which were recorded. These stages were (1) increase in forward locomotion; (2) head and paw rotation; (3) tactile visual avoidance; (k) circling; (5) backing; (6) reflexive stages. Upon reaching the reflexive stage a rat was placed in water, either 21.5° C or C, after which the rat dove underwater and exhibited many of the same stereotypies seen on land. Out of 19 subjects, 2 died during observation on land, 16 drowned in a mean time of f 0.2 seconds when placed in water If? minutes after the amphetamine injection (IP), 1 rat swam the required 9 minutes while under the influence of amphetamine.