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Negative patterning in classical conditioning:Summation of response tendencies to isolable and configural components* Six rabbits were given classical eyelid discrimination training involving "negative patterning," i.e., the reinforced presentation of two isolable cues, A+ and B+, and the nonreinforced presentation of their compound, AB-. The basis for discriminative responding which was thereby produced was evaluated by additionally reinforcing a third single cue, C+, and testing the responding to the novel compounds AC and BC as well as the responding to AB, A, B, and C. Although there was less responding to the nonreinforced compound than to any of the single cues, there was significantly more responding to the novel compounds, AC and BC. The results are consistent with the view that component response strengths summate to determine compound responding, but that there are functional, configurational components relatively unique to a stimulus compound.

The present study evaluated two assumptions of restraint theory. The first is that “restrained eating” and “dieting” are functionally equivalent. The second is that the effect of dieting on eating regulation is similar in normal‐weight and overweight individuals. The first hypothesis was tested by examining, using the standard forced preload paradigm, the eating of normal‐weight women classified as unrestrained nondieters, restrained nondieters, and restrained dieters. A significant restraint/dieting x preload interaction emerged. Restrained dieters ate much more without a preload than with one, while the two nondieting groups showed the opposite tendency. The second assumption was tested by reclassifying these normal weight subjects simply as dieters or nondieters and running additional groups of dieting and nondieting overweight subjects through the preload manipulation (creating a Weight x Dieting x Preload factorial). A three‐way interaction was found. Among normal‐weight subjects, nonpreloaded dieters overate; among overweight subjects, nondieters overate. Implications of these findings for restraint theory and the boundary model of eating were discussed.

Recent research on habituation suggests two separable sources of response decrement during a sequence of iterated stimulation-a transient, refractorylike decrement generated by recent stimulus presentations and a more persistent decrement that varies with the parameters of the overall sequence. The present research evaluated the refractorylike response decrement, as found in habituation of auditory evoked peripheral vasoconstriction in rabbits, to determine whether or not it represents a short-term habituation process distinct from effector fatigue or sensory adaptation. In each of three experiments subjects were exposed to pairs of discrete tones (Si-Sa) in which the second member was either the same as or different from the first member. Responding to Sa revealed a transient stimulus-specific decrement, that is, one that was present when Si was the same as Sa but not when Si was different from Sa. The stimulus-specific decrement was shown to be reduced by the interpolation of dishabituators between Si and Sa. And, finally, it was shown that the serial location of Si in a list of dishabituators modulated the stimulus-specific proactive effect on responding to S 2 . The pattern of findings is interpreted as evidence of a short-term habituation process and is discussed in terms of a dual-process unimechanism theory of habituation.

Four experiments, using a study-test paradigm, examined the effects of event presentation frequency on perceptual identification. In each cycle, subjects studied a list with different items presented from one to four or more times, then received identification tests of studied and nonstudied items. Pseudoword repetition (Experiments 1 and 4) produced a priming effect, that is, enhanced identification for presented items, and a repetition effect, that is, incremental improvements in identification for repeated items. In contrast, word repetition (Experiments 2, 3, and 4) produced priming but not repetition effects, a pattern that was not due to learning asymptotes or scaling distortions. We conclude that presentation frequency effects act on at least two distinct processing paths, selected on the basis of processing and task demands. Under conditions of simple exposure, perceptual enhancement is mediated, for codified events like words, primarily by nodal activation, and, for noncodified events like pseudowords, by information accumulation.

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Four experiments using a study-test paradigm provide evidence of differences in the nature of perceptual enhancement effects for words compared with results for meaningless pseudowords. Subjects studied words (Experiments 1,2, and 4) or pseudowords (Experiments 3 and 4) presented from 1 to 6 times in a list, then performed perceptual identification tests of studied and nonstudied items. Better identification of studied than of nonstudied items (i.e., a priming effect) was found for words and nonwords, but for words the function relating enhancement to the amount of prior exposure (i.e., a repetition effect) depended on whether subjects expected a later recall test. The results support dual-process accounts of word identification that assume a flexible use of either lexical code activation or episodic trace retrieval. A framework for understanding priming, repetition, and word frequency effects is discussed.I thank Maria Edano and Melissa Ciampi for help running subjects. Comments by several reviewers, including Aydin Durgunoglu, Larry Jacoby and an anonymous individual, were also appreciated.

The importance of configural cues and whether a situation involves beneficent or maleficent outcomes was investigated in two experiments on human causal reasoning, based on experienced causal information. Participants learned positive and negative patterning discriminations involving either beneficent or maleficent outcomes in a health-reasoning task and in a social-reasoning task. With maleficent outcomes, positive patterning was consistently easier to learn than negative patterning, a positive patterning advantage that is predicted by current associative theories and commonly taken as evidence for configural cues. However, with beneficent outcomes, the two discrimination tasks were not significantly different in ease of learning, a result not predicted by current theories. The reliable positive patterning effect found with maleficent outcomes broadens the range of conditions in which the effect can be shown in causal reasoning. The novel effect of outcome valence poses an interesting theoretical challenge for attempts to account for the relation between learning about individual cues and combinations of those cues.