George J. Wischner

Shock-right facilitation in an easy, noncorrection problem as effected by delay of reward ☆

Abstract To demonstrate shock-right (SR) facilitation utilizing an easy, bright-dark discrimination and noncorrection training, conditions under which SR training has previously had no effect or even a retarding one, the present study manipulated delay of reward for the correct response with shock administered in place of immediate food at the goal. Longer delays of reward led to more errors and trials to criterion and, associated with this increased difficulty, there was increased SR facilitation. Because the facilitation effect appears to depend on the extent to which shock can function as a “distinctive cue” to increase the discriminability of those stimuli that S experiences in the correct and incorrect goal arms, the findings suggest that the selectively facilitating, i.e., reinforcing, effect of a food object may well relate to its value as a distinctive cue. Taken in conjunction with other findings, the data also indicate that the SR facilitation effect has now been brought under experimental control: It can be produced where it formerly has not occurred and eliminated where it formerly has always occurred.

Discrimination performance as affected by duration of shock for either the correct or incorrect response

The present study extends our assessment of various shock parameters and training procedures as possible determinants of the paradoxical facilitating effect of shock for the correct response in discrimination training. Eighty hungry rats were trained with a non-correction procedure to make a light-dark discrimination for food under various durations of shock for either the right or wrong response. Trend analyses showed that, with greater durations of shock, errors decreased for the shock-wrong Ss but remained constant for the shock-right Ss and did not depart significantly from the performance of no-shock controls. The data delimit any broad generalization that shock for the correct response facilitates discrimination performance.

On the “secondary reinforcing” effect of shock for the correct response in visual discrimination learning

The finding that shock for a correct, food-reinforced response in visual discrimination training tends not to retard performance, and may even facilitate it, has been interpreted by some investigators as indicative of an acquired reinforcing property of the shock. To assess this interpretation, 40 hungry rats were given either no-shock or shock-right acquisition training, followed by extinction training in which the experimental Ss then received (a) shock for the previously correct response, as before, (b) no shock, or (c) shock for the previously incorrect response. The performances of these subgroups provided no evidence of an acquired reinforcing property of the shock, indicating instead an avoidance effect specific to the shocked arm.

RATE OF FORMATION OF ASSOCIATIONS BY SCHIZOPHRENIC AND NORMAL SUBJECTS AS A FUNCTION OF STIMULUS OR RESPONSE PLACEMENT OF AVERSIVE COMPONENTS

This study investigated the formation by schizophrenic and non-psychotic Ss of associations involving neutral and aversive stimulus components in two paired-associate paradigms. Both groups of Ss tended to form associations involving aversive stimuli faster than those involving neutral stimuli in both paradigms. These results were in marked contrast to those of a previous study in which the identical aversive words served as responses. The discrepancies in findings of the two studies were discussed in terms of certain characteristics of aversive words and differential reactions to them.