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61.
This study investigated whether an observed inverse relationship between self-stimulation and learning in autistic children is due to a physical inability of the subject to use the same body part for self-stimulation and task responding, or whether self-stimulation “distracts” the subject from task responding. Four actively self-stimulating autistic children were taught two discrimination tasks; one required a response that physically interferred with their self-stimulation; the other did not. Results were: (a) all subjects responded similarly across both tasks; (b) the three subjects with higher mental age scores learned both tasks without external suppression of self-stimulation; and (c) none of the subjects showed an inverse relationship between self-stimulation and learning. The study demonstrated that elimination of self-stimulation is not a necessary prerequisite for the acquisition of a new behavior in all autistic children.  相似文献   
62.
Four rhesus monkeys were trained to respond on one key when a one-second noise burst was presented through one speaker and to respond on a second key when the noise burst was presented through a second speaker. The acquisition of stimulus control was studied under three conditions, in each of which the relationship between the sound source and the response-key positions varied: an adjacent condition in which the noise burst was presented through the key and a response on this key was reinforced; a reversed-adjacent condition in which the noise burst was presented through one key and responding on the other key was reinforced: and a nonadiacent condition in which responding on the key nearer the sound was reinforced. Under adjacent conditions, stimulus control developed within one or two sessions. Under reversed and nonadjacent conditions, 10 sessions were required for the development of control. The asymptote of correct responding was the same under each condition in all animals.  相似文献   
63.
Six pigeons were trained to discriminate between two noise intensities using a procedure that assessed choice, time allocation, and response rate simultaneously and independently. Responses on the left or right key (R1 or R2) were respectively correct in the presence of two different intensities, S1 and S2. After a correct response, reinforcement became available for pecks on the center key. Reinforcement density for R1¦S1 relative to R2¦S2 was varied across experimental conditions. Generalization tests followed extensive training at each condition. As a function of stimulus intensity, proportions of initial choices of R2, of time spent in R2-initiated components, and of center-key responses emitted in R2-initiated components all yielded sigmoidal gradients of similar slope, which shifted slightly in location when relative reinforcement density changed. Changeovers were maximal where initial choice proportions approximated 0.5. Gradients relating the absolute number of center-key responses to stimulus intensity were also roughly sigmoidal, but were more sensitive to changes in reinforcement density. Gradients of momentary response rate also depended on reinforcement density. During training, large but transitory shifts in choice responding occurred when reinforcement density changed, while differences in momentary response rate developed slowly, suggesting separate control of choice and response rate by the contingencies of reinforcement.  相似文献   
64.
Eight retarded adolescents were trained to select one (a trained S+) of two visual stimuli in response to a spoken word (a trained word). Two different visual stimuli alternated randomly as the S-. To determine if the spoken work was merely a temporal discriminative stimulus for when to respond, or if it also specified which visual stimulus to select, the subjects were given intermittent presentations of untrained (novel) spoken words. All subjects consistently selected the trained S+ in response to the trained spoken word and selected the previous S- in response to the untrained spoken words. It was hypothesized that the subjects were responding away from the trained S+ in response to untrained spoken words, and control by untrained spoken words would not be observed when the trained S+ was not present. The two visual S- stimuli selected on trials of untrained spoken words were presented simultaneously. The untrained spoken words presented on these trials no longer controlled stimulus selections for seven subjects. The results supported the hypothesis that previous control by spoken words was due to responding away from the trained S+ in response to untrained spoken words.  相似文献   
65.
The stages of acquisition in stimulus fading   总被引:1,自引:1,他引:0       下载免费PDF全文
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   
66.
A paradigm for the control of visual fixation of the macaque monkey in vision experiments was described. Using a Maxwellian view, the procedure permits the placement of discrete test-light stimuli in a specific area of the retina as the monkey fixates a primary target. This procedure holds foveal fixation as other behaviorally significant visual stimuli are presented to the visual field. By a methods-of-limits procedure, the sensitivity of the monkey eye was measured at different retinal locations under both photopic and scotopic visual adaptation.  相似文献   
67.
The traditional interpretation of symptom over‐reporting is that it indicates malingering. We explored a different perspective, namely that over‐reporting of eccentric symptoms is related to deficits in articulating internal experiences (i.e., alexithymia). Given that alexithymia has been linked to sleep problems and that fatigue may fuel inattentive responding to symptom lists, we administered measures of alexithymia (TAS ‐20) and symptom over‐reporting (SIMS ), but also sleep quality (SLEEP ‐50) to forensic psychiatric outpatients (n = 40) and non‐forensic participants (n = 40). Forensic patients scored significantly higher on all three indices than non‐forensic participants. In the total sample as well as in subsamples, over‐reporting correlated positively and significantly with alexithymia, with r s being in the 0.50–0.65 range. Sleep problems were also related to over‐reporting, but in the full sample and in the forensic subsample, alexithymia predicted variance in over‐reporting over and above sleep problems. Although our study is cross‐sectional in nature, its results indicate that alexithymia as a potential source of over‐reporting merits systematic research.  相似文献   
68.
Abstract: Joining a vast Wittgensteinian anti‐theoretical movement, John Canfield has argued that it is possible to read the claims that (1) “language is essentially communal” and (2) “it is conceptually possible that a Crusoe isolated from birth should speak or follow rules” in such a way that they are perfectly compatible, and, indeed, that Wittgenstein held them both at once. The key to doing this is to drain them of any theoretical content or implications that would put each claim at odds with the other. I argue here, first of all, that it is not possible to detheorize both (1) and (2) and still hope to say anything illuminating about the nature of language. In fact, Canfield himself does not succeed in detheorizing both (1) and (2) but ends up trivializing (1) and leaving (2) with quite a bit of theoretical content. I further argue, however, that this is getting the matter the wrong way around. Contra Canfield et al., it is only when we recognize this that we can appreciate how radical and innovative Wittgenstein's claims about language really are.  相似文献   
69.
The aim of this paper is to highlight the role of the Decision Support System within the field of multi‐criteria decision aid (MCDA). The MCDA tools have been incorporated into systems to create Multi‐Criteria Decision Support Systems (MCDSSs). In our literature review, we noticed that more than 100 papers have been written over a 20‐year period in which MCDSS was used as a decision‐making tool. The present paper describes some real applications of MCDSS in different fields, harmoniously combined with decision‐making methods such as analytic hierarchy process, Utility Additive, and Goal Programming. The present study proposes an integrative MCDSS evaluation through guidance on the tools most useful for a specific user with a particular decision problem. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
70.
Adam Pryor 《Dialog》2021,60(1):97-102
Responding to the analyses that Andreas Losch and Lucas John Mix offer regarding Living with Tiny Aliens: The Image of God for the Anthropocene, this article begins to address how their respective concerns regarding ratiocentric and anthropocentric ideas haunt the construction of a planetary account of the imago Dei. The article then introduces a subsequent line of critique not mentioned by Losch or Mix related to decentering the human individual from accounts of the imago Dei in order to highlight an ongoing challenge for transdisciplinary theological projects that involve astrobiology.  相似文献   
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