Effect of deprivation state on successive negative contrast

Within-subjects positive and negative contrast effects in rats.

“…The deprivation conditions did, however, influence the latency measure: deprived rats responded faster overall, and showed a considerably larger NCE than nondeprived rats. The effect of the deprivation variable on negative contrast is consistent with findings from a number of runway studies (e.g., Ehrenfreund, 1971;Flaherty & Kelly, 1973) and indicates that the latency measure in the present paradigm may be functionally similar to running speed in more conventional instrumental paradigms. The differential effect of deprivation state on consummatory and instrumental response measures is also consistent with earlier data (e.g., Collier, 1962) The reliable occurrence of PCEs in the present study is at variance with the infrequent demonstration of positive contrast with other paradigms (Dunham, 1968).…”

Negative incentive contrast effects with sucrose and rats as due to aggression

“…The discrepant findings may be due to the different deprivation conditions selected by the present investigation (food and water deprivation) and the above-cited studies, which deprived subjects of only food or only water. There is good empirical support (e.g., Cleland, Williams, & DiLollo, 1969;Ehrenfreund, 1971;Ehrenfreund & Badia, 1962;Flaherty & Kelly, 1973) for the assertion that more severe deprivation schedules (as employed in the present study) are more likely to produce negative contrast effects than are less severe (water or food alone) deprivation schedules. It should be noted that a negative contrast effect has been obtained with constant-volume sucrose solutions as reward with both food and water deprivation (Weinstein, 1970a(Weinstein, , 1970b(Weinstein, , 1978 and with frequency of the lick response (Vogel, Mikulka, & Spear, 1968).…”

Expectancy, salience, and habit: A noncontextual interpretation of the effects of changes in the conditions of reinforcement on simple instrumental responses.

“…Obviously, contrast effects resulting from different levels of H should, all other considerations being equal, be more pronounced at higher levels of D. The observation that negative contrast increases with food-deprivation level (Ehrenfreund, 1971;Flaherty & Kelley, 1973) is thus consistent with the theory. Because the salience of A in relation to K in AK compounds might be expected to differ when A contains stimuli associated with high as opposed to low levels of D, assumptions regarding the weights assigned to D in the preceding equation as compared with drive-stimulus effects on the salience of A and K must be made before the present model has applicability to the effects of food deprivation on positive contrast.…”