Caged canaries exhibit two general repetitive stereotypies which have been termed route-tracing and spot-picking. Since certain stereotyped behaviors in chimpanzees have been related to level of arousal, and even regarded as mechanisms for regulating the arousal level, an attempt was made to determine the relationship between stereotypies and level of arousal in the canary. The arousal level was manipulated through administration of drugs known to affect arousal mechanisms. These pharmacological agents were administered orally 60 min before testing occurred. An equal volume of water served as the placebo. Stereotypies were counted in 5-rain observation periods, excluding time spent singing, feeding, drinking, and preening.
The results suggest that canary stereotypies reflect the level of arousal but do not serve to alter it. Drugs which cause decreases in arousal also produce decreases in the number of stereotypies. The effects of the arousal-raising drugs are variable and seem to depend on whether the drug exerts its effects mainly on increasing motor activity or on increasing responsiveness to external stimuli. The muscle relaxant carisoprodol apparently increases spot-picking by reducing proprioceptive feedback from muscles associated with pecking.