Abstract
Observation of hens in egg-laying cages indicates a high incidence of rotary spasms of the head. These movements are clearly related to movement frustration, being much less noticeable in chickens in large houses or on free range. Discussion follows of similar movements in other animals, i.e., weaving tic in horses, head bobbing in bears, stereotyped movements in certain caged animals in the zoo. The 2d half of the article is clinical, relating these observations to the head-rolling of infants and tic reactions in children.

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