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91.
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.  相似文献   
92.
Four young stutterers were observed during 10 weekly sessions. Each session was divided into pretreatment, treatment, and posttreatment segments. Redeemable tokens were administered contingent upon stuttering behaviors in the treatment segment of the Experimental condition. In a Parallel Control condition, no tokens were administered during the entire session. The differences between the pretreatment and treatment segments were compared for the two conditions. Three subjects had dramatically fewer stuttering behaviors when tokens were being administered, while the fourth had more stuttering under the same condition. The subject whose stuttering increased had a history of therapy in which voluntary, “faked” stuttering had been called for, and the behaviors that increased were judged to be of this type. The decreases were interpreted as suggesting that the contingent tokens acted to countercondition the aversiveness of the stuttering experience, which reduced the anticipation of stuttering and hence the stuttering itself. The increase was felt to be simple reinforcement. The counterconditioning interpretation was borne out in two clinical applications in which money was presented contingent on stuttering behaviors judged to be aversive to the stutterer, and in which dramatically sudden, but long-lasting, improvement was seen.  相似文献   
93.
The performances of two groups of retarded spellers (who were equated with respect to the level of deficient performance in spelling, but who differed in the level of phonetic accuracy of their misspellings) at two different age levels were compared to those of normal spellers who had been matched for age and WISC Performance IQ with the retarded spelling groups. The results indicated very marked differences in a number of linguistic skills between the normal spellers and the retarded spellers whose misspellings were characterized by phonetic inaccuracy. The performances of the retarded spellers who produced a preponderance of phonetically accurate misspellings differed markedly from those of the normal spellers only when the task demands involved fairly complex linguistic-cognitive operations. For the most part, the differences among the three groups were in evidence only at the older age level studied.  相似文献   
94.
Most phonological investigations of aphasic speech have focused on consonants. In this study, the vowel substitutions of five English-speaking Broca's aphasics were investigated with respect to several major explanatory hypotheses. An important possible motivating factor for aphasic substitutions, phonological environment, is an unlikely origin for these errors, since most substitutions occur along the paradigmatic axis. Another prominent hypothesis, markedness, also has no predictive power for the data of this sample. However, an analysis of the five Chomsky and Halle (1968, (The Sound Pattern of English), New York: Harper and Row) vowel features indicates that the two features for vowel height are selectively impaired: There is a strong tendency for lower vowels to replace higher targets. Moreover, the substitution sounds tend to be close to their target sounds along the height axis. Four possible hypotheses are advanced to account for this consistent lowering tendency.  相似文献   
95.
This experiment assessed the proposal that performance differences associated with field independence/field articulation reflect differential efficiency in the use of a limited capacity information-processing system termed working memory. Extreme scores on a group-administered version of the embedded figures test were used to identify subjects “high” and “low” in degree of field articulation. The task required that a subject retain a series of digits for subsequent report while performing a semantic modification of a target phrase. Concurrent information load on working memory was varied in two ways: by increasing memory load from 3 to 6 digits, and by increasing the complexity of the semantic processing required. In low information load conditions no differences were found between high FA and low FA groups. In high information load conditions low FA subjects made more errors in digit recall and took longer to perform the difficult semantic modification.  相似文献   
96.
Principal-components analysis was performed on a set of averaged evoked potentials in order to extract components of cerebral activity functionally related to hemisphere, handedness, processing task, and stimulus feature variables. Eight such components were isolated. Degree of dextrality, hemispheric differences, and cognitive operations in processing distinct stimulus characteristics were identified as reflected in functionally distinct components of brain activity.  相似文献   
97.
Investigated were differences in paired-associate learning for auditory versus visual modalities and within each modality the anticipation and study test methods of item presentation were compared. Extant reports re these two sensory modalities and of the two learning methods had been inconsistent. In this study of 40 university students, the learning of CVC-CVC nonsense syllable pairs was significantly better with the visual than with the auditory modality. The study-test method was significantly superior to the anticipation method in the visual mode. With auditory presentations, however, acquisition levels for both methods were the same. Significant interactions were observed between sensory modalities and methods of presentation. At present the retention interval theory (Izawa 1972–1979b) appears to account best for the varied findings with respect to the two methods of presentation.  相似文献   
98.
Slow brain potentials were recorded during the foreperiod of a reaction time task, and the effects of instructions governing the trade-off between speed and accuracy were investigated. One brain potential, a slow negative shift preceding S2, was largely attenuated under accuracy instructions. It is suggested that this shift is dependent on a motor response and that its amplitude reflects the level of motor preparation. Two other brain potentials, a slow positive and a slow negative wave, seem to depend on the psychological properties of S1. Enhanced amplitudes were found, when S1 provides information, besides its warning function.  相似文献   
99.
100.
This study purports to test a theory of life and career stages developed by Daniel Levinson and his associates. The theory suggests four distinct stages between ages 20 and 45 each with their own developmental tasks and related behaviors and attitudes. Subjects (759 managerial, professional, and technical employees) were selected randomly from levels and departments of a major public sector employer in the midwest United States. The measure of career stage asked respondents to indicate whether they had passed through, were still in, or had not yet reached each stage as operationalized by a short vignette. Attitudinal and behavioral measures were abstracted from previously developed instruments. Only moderate support for the theory was found with little or no evidence to support the age-linked notion of these stages. Stages were found to be discriminable in terms of certain attitudes (upward mobility, career and overall job satisfaction, and job commitment) as predicted. Suggestions are given for improvements in measurement, research design, and theory refinement.  相似文献   
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