Pre-encephalopathic Changes

The behavioral effects of aluminum have not been extensively studied. Crapper and Dalton described a number of behavioral changes in cats after infusion of aluminum chloride into the brain. 

They observed subtle changes in motor coordination 7 d postinjection. Animals were trained to jump from a height of 75 cm onto a platform that measured the sequence of limb impacts. At approximately 7 d post-injection their impact posture began to change, with the cats failing to break the fall by forelimb flexion. The difficulty in motor coordination increased such that by 12-18 d most animals landed so awkwardly that they refused to jump spontaneously. 

Similar behavioral results were more recently reported by Petit et al. in rabbits. Ten days after aluminum infusion, rabbits were trained on a step down active avoidance task, i.e., they were taught to step down from an elevated platform to avoid an electric 

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