Psychophysical Discrete Trial Method

A wheel manipulandum is usually used, although the method has been employed using a response lever. In this method, discrete trials are used, each demanding only a single response by the rat in order to receive the rewarding stimulation. A trial consists of an experimenter-delivered (non-contingent) stimulation. If the animal responds by turning the manipulandum within 7.5 seconds, it receives a second stimulation at the identical stimulation intensity as the first stimulus. Current intensities are varied in a stepwise fashion or descending and ascending order. This yields a response-intensity function, with the threshold defined as the intensity at which the animal responds to 50 percent of the trials. Of the methods currently used, this is the only one that does not make use of the response rate as an integral part of the procedure for the determination of the reward threshold— thus it is independent of the rate of response and the possible confounding motor effects of the drug.

Defeat Drugs and Live Free

Defeat Drugs and Live Free

Being addicted to drugs is a complicated matter condition that's been specified as a disorder that evidences in the obsessional thinking about and utilization of drugs. It's a matter that might continue to get worse and become disastrous and deadly if left untreated.

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