Assessment of Neurological Effects of Drugs on Oculomotor and Visual Function in the Primate

摘要

A number of cholinergic agents are deemed useful as prophylactics or antidotes to organophosphate poisoning yet have their own toxic effects. Dosages of these agents which are known to not grossly disrupt behavior may nonetheless degrade performance of sophisticated tasks required of the personnel of a modern mechanized army. The contract uses on animal model (primate) to assess the effects of cholinergic drugs on the performance of visual search and tracking tasks which mimic skills generally used in the field. The eye movements of cynomolgous monkeys (Macaca fascicularis) were recorded with the magnetic search coil technique while they searched for camouflaged visual targets. To date the research has defined the normal patterns of eye movements of monkeys engaged in visual search and there are preliminary results describing the effects of physostigmine and pralidoxime. Only at the highest dose did physostigimine consistently degrade eye movements and impair visual search. The deficit was a subtle one and was primarily an oculomotor effect rather than a motivational, visual, or cognitive impairment. Pralidoxime also had no consistent effect at any but the highest dose. Behavioral testing was erratic at this dose but visual search was successful when attempted at all by the monkey, suggesting a motivational rather than specifically oculomotor impairment.