| Popis: |
Monkeys which drank small doses, once daily, of methadone mixed with Tang orange drink were trained to perform a series of two-object visual discrimination problems. Their average number of trials to criterion was the same as that of normal monkeys, and they made the same number of errors on test trials in which the orientation of the stimulus objects was changed. Their average choice latencies, however, were significantly longer than those shown by the normal group. In a second experiment, on each trial Ss were given a decision interval to observe the stimulus objects. Latencies, as measured from the end of the interval, were the same for control and methadone-consuming monkeys. These data suggest that the previously elevated latencies were not due to motor or motivational lethargy, but to a drug-induced prolongation of the time necessary to decide which was the correct object. |
