Catatonia in birds

Conclusions

A state of intoxication resembling in many respects that of catatonia can be induced in birds by injections of bulbocapnine in doses varying from five to ten per cent of the body weight of the animal. Compared with the catatonic state likewise induced in higher animals such as the mouse, the cat and the monkey, the catatonic manifestations in birds are somewhat imperfectly developed. In the presence of external stimuli they tend to disappear. These observations tend to show that birds occupy in this respect an intermediate position between the mammals and those animals devoid of a neo-cortex.

When larger doses of bulbocapnine are given to birds a more stable condition of immobility can be obtained. Still larger doses are followed by motor phenomena characteristic of a state of hypercitability and hyperkinesis which may be terminated with tonic spasms, convulsions and death. The hyperkinetic reaction to large doses of bulbocapnine is not unlike that induced by excessive doses of numerous other motor excitants.

These experiments may be regarded as producing additional evidence of toxic factors in human catatonia. The reproduction of catatonic phenomena experimentally suggests that toxic as well as psychogenic factors must be investigated before the secrets of this disease can be known.