The extinction of within-compound flavor associations

Three experiments studied extinction of the associations which are formed between two flavors presented in a simultaneous compound. In Experiment 1 those associations were identified by a sensory preconditioning procedure in which the poisoning of one element of the compound led to the rejection of the other element. Separate presentation of either element between their joint occurence and the poisoning of one element sharply attenuated the rejection of the other element. That attenuation was interpreted in terms of the extinction of within-compound associations. Experiment 2 obtained similar results with an alternative extinction procedure in which the elements of the original compound were presented in other compounds. Experiment 3 obtained similar results when the existence of the within-compound associations was determined by an alternative assessment procedure in which one element of the compound was made more attractive by the induction of a specific hunger. These experiments suggest that within-compound associations can be extinguished when the elements are separately presented outside of the compound. Experiments 2 and 3 make less plausible an alternative interpretation of the effects of separate element presentation in terms of reduction of the novelty of the element. The findings may be taken as implying that the elements of a simultaneously presented compound are joined by a single symmetrical association which acts at various points during a sensory preconditioning experiment.     

Cerebral lateralization in individuals diagnosed as autistic in early childhood

Early infantile autism was found to be associated with an atypical pattern of cerebral lateralization. Based on EEG measures of hemispheric activation during cognitive processing, it was found that 7 of the 10 autistic individuals tested showed a pattern of hemispheric specialization rarely seen in the normal population; namely, a “reversal” in lateralization reflective of a lack of left-hemisphere specialization for linguistic functions. Furthermore, the autistic individuals' pattern of cognitive strengths and weakness is suggestive of a selective impairment of the left cerebral hemisphere.     

Experimentally induced phonological paraphasias.

A motor aphasic patient had to repeat word lists that contained, among other things, words with the sequences r - r - l and l - l - r. These sequences were often repeated as l - r - l (anticipatory distant assimilation) and r - l - r (same type, but less frequently), respectively. These assimilations violate the cross-over constraint (or relevancy condition or adjacency principle) and thus represent another instance of a flagrant contradiction between pathological and normal (natural) phonological processes.     

Hemisphere functioning and motor imitation in autistic persons

Previous research has found that a high proportion of autistic individuals exhibit an atypical pattern of hemispheric specialization suggestive of impaired left hemisphere functioning: namely, right hemisphere dominance for both verbal and visual-spatial processing. Studies of brain-damaged persons have suggested that the left hemisphere is specialized for the use of nonverbal gesture. Since a major characteristic of autism is an impairment in the use of gesture, it was predicted that autistic persons would also show atypical hemispheric specialization for motor imitation. To test this hypothesis, hemispheric activation was measured using EEG recordings of alpha rhythm in autistic and matched normal control subjects during four motor imitation tasks. Autistic subjects showed significantly greater right hemisphere activation during the imitation tasks, than normal subjects. This pattern was particularly evident in younger autistic subjects and during oral, rather than manual, imitation tasks.     

Recovery of the US representation over time during extinction

Four experiments used a conditioned suppression procedure in rats to explore changes in the US representation over time during the course of extinction. They employed two previously reported effects: reinstatement of responding to an extinguished CS by separate US presentation, and the erasure of that effect by interposed nonreinforcement of a second excitatory CS. These effects have been interpreted as enhancing and depressing the US representation, respectively. Experiment 1 found the erasing effect to decrease but still to remain substantial after over a 4-day period, suggesting a partial recovery with time of a deliberately depressed US representation. Experiment 2 implicated this change as a contributor to the phenomenon of spontaneous recovery by showing that recovery to be sensitive to erasure effects. Experiments 3 and 4 found evidence for an interaction between the state of the US representation and the amount of associative change which results from nonreinforcement of an excitatory CS. When the US representation was strong, either because of reinstatement or the passage of time, nonreinforcement of a CS was especially effective in producing associative change. When the US representation had been depressed by erasure, those nonreinforcements produced relatively less associative loss. Moreover, these effects upon associations were reasonably stable in the sense that they left asymptotic differences in the strength of associations after extinction. Together with previous findings, these results point to an important role for the US representation in the performance and learning which occurs during extinction.     

Determinants of reduction in intended effort as a strategy for coping with anticipated failure

The present study investigated the use of reduction in intended effort as a strategy for protecting self-esteem from the threat of anticipated failure. It was hypothesized that people reduce the amount of effort they intend to exert when they expect a low probability of success on a highly ego-relevant task. Female subjects anticipated taking an easy (high probability of success) or difficult (low probability of success) test that was either high or low in ego relevance. Subjects' levels of intended effort and other task-relevant cognitions were assessed. It was found that subjects in the low-probability condition intended to exert less effort on the highly ego-relevant test than did subjects in the high-probability condition; probability of success had no effect on intended effort level on the low ego-relevance test. Subjects also reported that it was a worse day for a test in the low-probability condition than in the high-probability condition. The relevance of these findings to the egotism explanation of learned helplessness effects and general theories of motivation was discussed.     

Individual differences in the ability to focus and divide attention

This research deals with individual differences in the ability to focus and divide attention. Eighty-five subjects performed visual search and auditory detection tasks in three conditions: single channel, focused attention, and divided attention. Reaction time (RT) was fastest in the single channel condition, intermediate in the focused attention condition, and longest in the divided attention condition, and these effects were much stronger in the auditory than the visual task. Correlations among RTs in the three conditions were very high within modality (>.88), and lower between modalities (.5 to .6). The correlational data was well fit by a model that included separate factors for the visual and auditory tasks. Measures from the three attentional conditions within each modality loaded equally on these factors. The data provided no evidence for distinct abilities to divide or focus attention.     

Second-order conditioning with diffuse auditory reinforcers in the pigeon

Pigeon subjects were used in five experiments investigating second-order conditioning with visual second-order and diffuse auditory first-order stimuli. Experiment 1 used a discriminative conditioning procedure to demonstrate reliable and substantial second-order conditioning with these stimuli. In Experiments 2 and 3, extinction of the auditory first-order stimulus after second-order conditioning had little effect upon responding to the second-order stimulus, when compared to a stimulus whose reinforcer was maintained. Experiment 4 compared directly the susceptibility of second-order responding to extinction of the first-order reinforcing stimulus as a function of the modality of that reinforcer. When a visual second-order stimulus was paired with a visual reinforcer, and the response to the latter was extinguished, then second-order responding was greatly reduced relative to control levels. In contrast, when that reinforcer was an auditory stimulus, second-order responding was not affected by the current value of the first-order stimulus after conditioning. Finally, in Experiment 5 the auditory stimulus was established as a reinforcer through discriminative-operant training. Following second-order conditioning, extinction of responding to this stimulus again had little impact upon responding to the second-order stimulus with which it had been paired. These results are discussed in terms of previous work on second-order conditioning with rat and pigeon subjects.     

Social comparison after success and failure: Biased search for information consistent with a self-serving conclusion

Based on the traditional and attributional perspectives on social comparison, it was hypothesized that the search for social comparison information after performance outcomes is biased so as to provide evidence consistent with a favorable self-evaluation. In Experiment 1, subjects were led to believe that they obtained 16 or 8 out of 20 items correct on a bogus social sensitivity test and were then led to expect that most other students performed either well or poorly on the test. They were then given the opportunity to inspect up to 50 scored answer sheets from previous subjects. Consistent with the hypothesis, failure subjects requested more information when they expected it to reveal that most students performed poorly than when they expected it to reveal that most students performed well; success subjects showed little interest in this additional information, regardless of their expectancies as to what it would reveal. Experiment 2 employed a different approach to manipulating performance outcomes and led subjects to expect that most other subjects performed better, the same, or worse than themselves. Regardless of their own performance, subjects showed the least interest in additional information in the higher score expectancy condition and the most interest in additional information in the lower score expectancy condition. The role that this information search bias may play in producing self-serving attributions for success and failure and maintaining positive self-evaluations was discussed.     

Cognitive and motivational determinants of children's humor responses

Cognitive and motivational influences on children's humor responses were examined. Forty-eight Caucasian children from three economically heterogeneous schools were tested. Equal numbers of middle SES and lower SES boys and girls from kindergarten and third grade were shown 12 aggression and dependency cartoons of different difficulty levels. Three responses to each cartoon were recorded: mirth, funniness rating, and comprehension score. Results support aspects of both psychodynamic and cognitive theories of humor response. All children preferred aggressive themes to dependency themes, and third graders especially showed attenuated response to dependency cartoons. Funniness ratings decreased as difficulty levels increased. IQ, as assessed by the Peabody Picture Vocabulary Test-R, was positively related to humor. Mirth responses and funniness ratings increased as comprehension increased.