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991.
Two parallel experiments used pigeons in a transfer of control design to determine the basis of the transfer of the use of the “advance strategy” across successive discriminations (W. K. Honig & H. Lindsay, Learning and Motivation, 1975, 6, 157–178). Pigeons were first trained under instrumental contingencies to use an “advance” response to maximize their exposure to SD and minimize their exposure to SΔ. Then orthogonal stimuli (key lights in Experiment 1 and diffuse illuminations in Experiment 2) were independently established through separate discriminative Pavlovian procedures as CS+ and CS? or as CSo's. Later in special tests, it was demonstrated that the associative values of the Pavlovian CS's were a major factor governing the use of the advance strategy: only pigeons exposed to CS+CS? used the advance response to regulate their exposure to either CS. Although these experiments showed that the necessary and sufficient conditions for utilization of the advance strategy are the Pavlovian associative values of the discriminative stimuli, opportunity for differential “operant” responding during the discriminative stimuli seems to be a contributor to the optimal use of the advance response across successive discriminations.  相似文献   
992.
993.
This report details the reliability of perceived parental and childhood illness behavior. Three versions of the Illness Behavior Inventory were created to assess perceived illness behavior of one's mother, father, and oneself as a child. The measures were administered twice to 32 students of linguistics at a major university with a 2-wk. interval between administrations. Each measure across administrations correlated highly and significantly (.98 to .99). It was concluded that perceptions of parental and childhood illness behavior are reliable over time but their sensitivity to actual historical events remains an empirical question.  相似文献   
994.
9 obese and 9 normal subjects performed a psychophysical task in which food- or non-food-related stimuli were briefly flashed tachistoscopically at a speed and intensity near the visual threshold. A signal was presented on one-half the trials and noise only on the other one-half of the trials. Using signal detection theory methodology, separate measures of sensory sensitivity (d') and response bias (beta) were calculated. No differences were noted between obese and normal subjects on measures of sensory sensitivity but significant differences on response bias. Obese subjects had consistently lower response criteria than normal ones. Analysis for subjects categorized by whether they were restrained or unrestrained eaters gave findings identical to those for obese and normal. The importance of using a methodology that separates sensory and non-sensory factors in research on obesity is discussed.  相似文献   
995.
In order to investigate the proposal that modifications in developmental rate may mediate differences in aggressive behavior, two series of selective breeding studies were completed. Stable lines of mice that differed in the frequency and latency of attacks were rapidly established in two series (by S1 in the first series and S3 or S4 in the second series). For evaluation of the developmental-genetic proposal, an analysis was made of the ontogeny of aggressive expression in male mice of the two series, with a detailed report provided of the S1 and S4 generations of the second breeding series. Comparisons between the results of a longitudinal design and the results of a new type of cross-sectional design (involving only siblings, or co-sibial) indicated (a) a reliable developmental course of attack expression, with a sharp rise in early maturity and a slow decline thereafter; (b) a convergence in later maturity of the behavior of lines selectively bred for high or low aggressive behavior, if the animals had been assigned to the longitudinal design; (c) a strong effect of repeated testing on attack latency and frequency, even though the dyadic tests were brief in duration and separated by long intervals. In addition, cross-generational comparisons suggested that the selective breeding differences came about primarily by changes in the behavior of the low aggressive lines, in that these animals failed to show in early maturity the sharp increases in attack occurrence that were observed in earlier generations. Certain implications of these findings for developmental and evolutionary concepts (e.g., neoteny, acceleration, heterochrony) are discussed.  相似文献   
996.
It has been suggested that psychopaths exhibit specific deficits in cognitive processes associated with frontal lobe functioning. There is also evidence which indicates that level of intelligence may influence expression of impulse control among psychopaths. The present study investigated these hypotheses by comparing groups of 44 psychopaths and 14 normal controls selected from a sample of incarcerated male felons using Minnesota Multiphasic Personality Inventory (MMPI)-defined criteria. Dependent variables included several measures of cognitive flexibility, perseveration, and impulsiveness. Compared to normal controls, psychopaths showed no greater tendencies to persist in incorrect responding, disregard cues suggesting the need to modify behaviors, or proceed impulsively in problem solving. Level of intelligence was found to be a moderator variable influencing performance for psychopaths and normal controls. Results suggest that deficits in cognitive functioning are not necessarily characteristic of psychopaths across situations.  相似文献   
997.
Few efforts have been made to understand antisocial-prone individuals who maintain adaptive functioning. This study identified a sample of potentially deviant but adaptively functioning persons to determine whether they differed significantly from their more conforming peers. A small sample of men was selected by Minnesota Multiphasic Personality Inventory (MMPI)-defined criteria for sociopathy and compared with MMPI-defined normals of similar ages, backgrounds, and intelligence. Response variables were those cited in the literature as characteristic of sociopathic psychopathology and included measures of abilities to plan ahead and inhibit impulsiveness, sensation seeking, interpersonal performance and style, and behavior conformity. Men labeled adaptive sociopaths showed greater impulsiveness and needs for experience seeking, earned lower scores on measures of socialization and self-control, and admitted greater adolescent behavior deviance. They were not shown to be less empathetic or less able to relate interpersonally in interview. The potential role of socially constructive self-determined goals and tangible vocational rewards as mediators of adaptive behavior are discussed in terms of overcoming antisocial tendencies and attenuation of behavior disinhibition.  相似文献   
998.
An adaptive psychometric procedure that places each trial at the current most probable Bayesian estimate of threshold is described. The procedure takes advantage of the common finding that the human psychometric function is invariant in form when expressed as a function of log intensity. The procedure is simple, fast, and efficient, and may be easily implemented on any computer.  相似文献   
999.
The present study examined the plasticity of the human perceptual system by means of laboratory training procedures designed to modify the perception of the voicing dimension in synthetic speech stimuli. Although the results of earlier laboratory training studies have been ambiguous, recently Pisoni, Aslin, Perey, and Hennessy (1982) have succeeded in altering the perception of labial stop consonants from a two-way contrast in voicing to a three-way contrast. The present study extended these initial results by demonstrating that experience gained from discrimination training on one place of articulation (e.g., labial) can be transferred to another place of articulation (e.g., alveolar) without any additional training on the specific test stimuli. Quantitative analyses of the identification functions showed that the new perceptual categories were stable and displayed well-defined labeling boundaries between categories. Taken together with the earlier findings, these results imply a greater degree of plasticity in the adult speech processing system than has generally been acknowledged in past studies.  相似文献   
1000.
The reported direction of autokinesis for naive observers is not biased by gaze deviations of 22.5 deg of arc. However, instructions to expect either “inward” or “outward” movement produce reports of autokinetic movement that are progressively biased in the expected direction. Instructions to expect “more” or “less” movement resulted in a decrease in the reported duration of apparent movement for the “less” group but no change for the “more” group. Response bias is not considered to play a role in these results. The results are discussed in terms of fixational bias and selective attention mechanisms of autokinesis.  相似文献   
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