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311.
Discriminability between alternatives in a switching-key concurrent schedule 总被引:1,自引:1,他引:0
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Six pigeons were trained to discriminate between two intensities of white light in a symbolic matching-to-sample procedure. These stimuli were then used to signal which schedule was available on the main key in a switching-key concurrent schedule. The concurrent schedules led to a symbolic matching-to-sample phase in which the subject identified the concurrent schedule to which it last responded before a reinforcer could be obtained. The concurrent schedules were varied across conditions. Discriminability, measured during the symbolic matching-to-sample performance, was high throughout and did not differ across the two procedures. Performance in the concurrent schedules was like that typically obtained using these schedules. Delays were then arranged between completion of the concurrent schedules and presentations of the symbolic matching-to-sample phase. A series of conditions with an intervening delay of 10 s showed that both concurrent-schedule performance and symbolic matching-to-sample performance were affected by the delay in a similar way; that is, choice responding was closer to indifference. 相似文献
312.
The scale illusion (Deutsch, 1975) shows the importance of frequency range in the perceptual organization of a sequence of notes. This paper includes three experiments on the scale illusion. Experiments 1 and 2 demonstrated that if the structure of the pattern of notes used in the original scale illusion study is altered slightly, by adding or subtracting a pair of notes from the ends of the sequence, there is a significant decrease in the rate of frequency-based responses, suggesting a weaker illusion. Experiment 3 investigated two features of the note patterns that may have led to this change. Specifically, it asked whether the decrease in the strength of the illusion is due to (1) the nature of the notes at the extremes of the frequency range and/or (2) the nature of the notes at the crossing point of the two scales. While both sources were found to affect the strength of the scale illusion, the former had a greater influence. 相似文献
313.
The Brain-Age Quotient (BAQ) of Reitan has been proposed as a means of studying age-related cognitive differences. This study examined age and education correlates of the BAQ and a BAQ short form. A heterogeneous group of 100 subjects were selected from the neuropsychological testing case records published by Golden, Osmon, Moses, and Berg in 1981, Boll (undated), and Reitan (undated). Results suggest the BAQ and the BAQ short form are not significantly correlated with age and education. 相似文献
314.
Assessors evaluated assessees'performances in one of three performance conditions in an assessment center simulation: a consistent performance condition, a within-assessee performance variation condition, or a between-assessee performance variation condition. Contrast effects influenced ratings of assessees when there was variation in performance within assessees. For each assessee, the low target performance was rated lower when the assessee's prior performance had been dissimilar (high) than when the assessee's prior performance had been similar (low). Contrast effects also infiuenced assessors'ratings of the target assessee when there was variation in performance among assessees. The low performing target assessee was rated significantly lower when he was evaluated with two high performers than when he was evaluated with two low performers. In addition, ratings obtained when there was performance variation among assessees were more accurate than those obtained when there was no performance variation, suggesting that under some circumstances contrast effects may not lead to inferior judgments. 相似文献
315.
The classical visual latency explanation of the Pulfrich phenomenon is generalized to allow for the possibility that the visual system uses velocity information from motion detectors to compensate for spatial lag due to time lag, in identifying the instantaneous position of a moving object. The results of the reported experiment verify one consequence of the generalized version: the elliptical apparent path is skewed away from the filtered eye. The results suggest also that the extrapolation factor increases with visual latency and that there is a different extrapolation factor for each eye when the eyes are illuminated unequally. 相似文献
316.
R A Jones G D Morrow B R Morris J B Ries D R Wekstein 《Perceptual and motor skills》1992,74(1):227-238
The research was intended to identify the dimensions underlying self-perceived information needs and concerns of an elderly population. The spontaneously mentioned needs and concerns expressed in 271 letters from a sample of the population were extracted and a multidimensional scaling procedure was used to represent the 58 most frequently mentioned items in configurations of varying dimensionality. To interpret the multidimensional spaces, another sample of 176 elderly subjects was asked to rate the 58 concerns on eight properties. These ratings were then regressed onto the multidimensional configurations. The results indicate that the most frequently mentioned information needs and concerns of elderly persons can be parsimoniously understood in terms of three underlying dimensions: (1) Improving the Quality of Life vs Securing the Necessities of Life, (2) Health-related vs Not Health-related, and (3) Individual vs Societal Responsibility. 相似文献
317.
A paradigm for studying oral sensory tactile function through use of single frequency vibration applied to the dorsal surface of the tongue was administered to a group of 10 young black women and 10 young white normal-speaking women. Analyses showed no differences between groups with regard to lingual vibrotactile threshold of sensitivity or suprathreshold magnitude-estimation scaling responses. 相似文献
318.
The purpose of this study was to investigate differences in function of the tactile sensory system between groups of normal-speaking children and children with articulation problems. This task was accomplished by studying possible tactile threshold shifts occurring during magnitude-estimation scaling of vibratory stimuli presented to the dorsal surface of the tongue. 10 normal-speaking children (M age = 7.8 yr.) and 9 children with articulation problems (M age = 7.5 yr.) participated. The normal-speaking children and articulatory defective children performed differently on the magnitude-estimation scaling task in which threshold was allowed to return to baseline after each stimulus presentation. These two groups of children also showed dissimilar threshold shifts for the suprathreshold intensities employed in the magnitude-estimation scaling. 相似文献
319.
P Tassi A Nicolas G Dewasmes R Eschenlauer J Ehrhart P Salame A Muzet J P Libert 《Perceptual and motor skills》1992,75(1):291-302
The purpose of the present study was to analyse the arousing effects of noise on sleep inertia as a function of circadian placement of a one-hour nap. In a first experiment, we measured the effects of sleep inertia in a neutral acoustic environment after a one-hour nap placed either at 0100 or 0400 on response time during a spatial memory test. In a second experiment were analysed the effects of an intense continuous noise on sleep inertia. The results showed that noise produced a total abolition of sleep inertia after an early nap (0000 to 0100). This may be due to the arousing effect of noise; however, results are less clear after a late nap 0300 to 0400 as noise seems to be ineffective. This result is discussed in terms of either a function of time-of-day effect or of prior sleep intensity. Moreover, our data suggest a possible interaction of noise with partial sleep deprivation leading to a slight deleterious effect those subjects who did not sleep at all. 相似文献
320.
Deborah G. Mayo 《Synthese》1992,90(2):233-262
I document some of the main evidence showing that E. S. Pearson rejected the key features of the behavioral-decision philosophy that became associated with the Neyman-Pearson Theory of statistics (NPT). I argue that NPT principles arose not out of behavioral aims, where the concern is solely with behaving correctly sufficiently often in some long run, but out of the epistemological aim of learning about causes of experimental results (e.g., distinguishing genuine from spurious effects). The view Pearson did hold gives a deeper understanding of NPT tests than their typical formulation as accept-reject routines, against which criticisms of NPT are really directed. The Pearsonian view that emerges suggests how NPT tests may avoid these criticisms while still retaining what is central to these methods: the control of error probabilities.A portion of this research was carried out during tenure of a National Endowment for the Humanities Summer Stipend Fellowship; I gratefully acknowledge that support. A version of this paper was presented at the 1987 meeting of the Society for Exact Philosophy. This paper benefited from discussions and communications with George Barnard and Isaac Levi. I thank Harlan Miller for helpful comments on earlier drafts. 相似文献