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921.
Pigeons were exposed to a stimulus fading procedure in which control of responding was transferred from red and black stimuli to lines of different angular orientation. After superimposing one line on the red stimulus and the other line on the black stimulus, the intensity of the lines was gradually increased and that of the red stimulus was gradually reduced. Probes consisting of red and line stimuli presented separately were used during the course of fading to assess control exerted by each element of the compound. As the lines were faded in, they did not acquire control of responding. As red was faded out, control of responding was acquired first by the lower intensity red stimuli in combination with the line stimulus, and finally by the angular orientation of the lines. Probes also determined the point at which the line stimuli, presented alone, would maintain a high degree of stimulus control. The results demonstrated that new stimuli in fading acquire dimensional control of responding in two sequential stages. Acquisition of stimulus control in fading was explained in terms of attenuation of stimulus blocking. 相似文献
922.
923.
924.
The properties of serial position functions for tachistoscopic report were investigated over a wide range of viewing times. Four-letter strings of random consonants were presented in varying display locations relative to the fixation point with the observers’ eye movements monitored to limit them to a single fixation for each display. Salient properties of the serial position curves include an overall central-peripheral gradient, higher performance at the ends than the interior of letter strings regardless of absolute location, and left-right asymmetry in the visual field, all of these being largely independent of viewing time. Errors reflecting loss of positional information are prominent even at extended viewing times, are more nearly symmetrical in the left and right visual fields than other types of errors, and, in contrast to item errors, occur less frequently in letter sequences that have high frequencies in English. Further, transposition errors exhibit a pronounced peripheral-to-central drift, possibly reflecting gradients of positional uncertainty. Such gradients may be implicated in the peripheral-central asymmetry of the lateral interference effects exerted by other letters on a target letter in a nonfoveal location. 相似文献
925.
John K. Collins 《Attention, perception & psychophysics》1976,20(1):45-48
The effect of a digital block on the voluntary positioning of the index finger from a point of extreme extension through 45° flexion was examined in 12 subjects. A xylocaine ring block of the second proximal interphalangeal joint was used to eliminate the joint receptors while weights were attached to the finger. An inverse relationship was found between weight and distance moved when the subject was required to move the index finger of the nonpreferred hand to the required position. The results indicate that the muscular system is ancillary to the joint system in proprioceptive space perception. 相似文献
926.
Calvin K. Adams Deborah C. Hall H. S. Pennypacker Mark Kane Goldstein Larry L. Hench Michael C. Madden Gerald H. Stein A. Charles Catania 《Attention, perception & psychophysics》1976,20(3):163-167
Sixteen observers palpated silicone models of human breasts containing lumps 1.6-12.1 mm in diameter. Detectability depended on the size of the lump, producing a systematic psychometric function. In eight observers who participated in three or more sessions, performance improved with practice, with most improvement occurring within one or two 26-trial sessions. Three-week retention measures disclosed no appreciable decrease in performance, but a significant correlation was found between the number of lumps detected and duration of trial (p < .01). There was no difference in performance between four observers who used their preferred hands and four observers who used their nonpreferred hands. These data establish that examination of breast models for the detection of lumps simulating cancer is a task amenable to experimental analysis. 相似文献
927.
Lee Willerman Robert Gerald Turner Marsha Peterson 《Journal of research in personality》1976,10(4):482-492
Most personality tests are based on concepts assessing typical performance, and tests of this sort have not been generally successful in predicting criterion behaviors with useful levels of efficiency. Ability tests, which call for maximal performance, have been much more successful as predictors of criterion outcomes. Following a model derived from ability tests, predictors requiring separate typical and maximal self-reports of emotional expressivity were compared to measures of typical and maximal emotional expression in the laboratory. For angry expression, self-reports of maximal expressivity tended to outpredict self-reports of typical expressivity for both typical and maximal laboratory measures of angry expression. Although similar trends were observed for elation, the advantage of maximal self-report measures over typical self-report measures was negligible. Results were discussed in terms of both experimental and clinical implications. 相似文献
928.
Ronald E Smith John P Keating Reid K Hester Herman E Mitchell 《Journal of research in personality》1976,10(3):346-357
This study was designed to assess the extent to which social role and “just world” considerations would affect perceptions and attributions of responsibility to a rape victim. The rape victim was either a topless-bottomless dancer, a social worker, or a Catholic nun, and she was either acquainted or unacquainted with her assailant. In the acquainted condition, the dancer was attributed the greatest and the nun the least amount of responsibility, indicating that social role factors can govern the range of attributional judgments which might be made in any given instance. However, unacquainted victims were ascribed more responsibility for the rape than were acquainted victims, a difference which was significant when the victim was the nun. The latter findings are discussed in terms of Lerner's just world hypothesis. Significant sex differences were found in subjects' perceptions of and responses to the rape incident and, contrary to earlier findings, no relationship was found between victim attractiveness and punitiveness toward the wrongdoer. 相似文献
929.
A group of 16 children from a normal community population was compared with two groups of 16 children referred for clinical evaluation of hyperactivity. These three groups were matched on age, sex, and race. One of the clinic groups was matched with the community sample on IQ and social class as well, while the children in the other clinic group were mentally retarded and of somewhat lower social class. All children were observed in a standardized playroom for two 15-minute sessions, one under free play instructions and the other under instructions restricting activity and toy-changing behavior. The two groups of children referred for evaluation of hyperactivity had significantly higher playroom activity scores than controls under both instructional conditions and significantly higher toy-change scores under restrictive instructions. Parental ratings of activity were also significantly higher in both clinic groups than in the community group. The mentally retarded clinic sample did not differ from the other clinic sample on any of the measures of activity or toy switching.A preliminary version of this article was presented at the meeting of the American Psychological Association, Chicago, Illinois, August 30, 1975, as part of a Symposium on Hyperactive Children: Assessment, Treatment, and Outcome. This research was supported by U. S. Public Health Service, Maternal and Child Health Project No. 916 and by Grants HD-03110 and ES-01104. 相似文献
930.
D M Green A K Purohit 《Journal of experimental psychology. Human learning and memory》1976,2(1):32-37
Recognition memory for pictures was tested using matrices of 0s and 1s as stimuli in two experiments. In the first experiment dimensionality of matrices was varied (5 X 5 and 10 X 10 matrices). The results showed better recognition memory for 10 X 10 matrices. The second experiment investigated the importance of certain areas, such as center or surround, using 10 X 10 matrices only. The results suggested that neither center nor surround is given unusual weight. 相似文献