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71.
Deep dyslexia in childhood? 总被引:1,自引:0,他引:1
L S Siegel 《Brain and language》1985,26(1):16-27
Deep dyslexia is an acquired reading disorder in which semantic substitutions (e.g., city read as town) are made in reading single isolated words. In this paper, evidence for deep dyslexic-type errors is presented from the word-recognition responses of six children, aged 7 years and 0 month to 8 years and 9 months, with severe reading disorders. These semantic substitutions occur in the absence of phonological skills. Therefore, it appears that there exists a small subset of developmental dyslexics who at the beginning of acquisition of reading skills are able to engage in semantic processing, but who show severe impairment of phonological processing. The existence of these reading errors indicate that the use of a phonological code is not necessary to extract meaning from the printed word. 相似文献
72.
Four chronic global aphasics were treated with Blissymbols (C. K. Bliss, 1965, Semantography-Blissymbolics, Sydney: Semantography Pub.). As soon as possible the therapeutic communication was based solely on the use of the symbols. Three patients seemed to benefit from therapy. In one case therapy had to be discontinued because of massive perseveration. In one patient expression of needs relied solely on the use of the symbols. In another, expressive speech could be restored to such an extent that communication by the use of symbols was discontinued. 相似文献
73.
Observers detected a briefly flashed target letter embedded in word, pronounceable nonword, and unpronounceable nonword contexts. The word context facilitated perception under both holistic and analytical processing strategies; the facilitative effect was enhanced when processing was analytical. 相似文献
74.
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76.
Michael Washburn 《Zygon》1987,22(1):67-85
Abstract. Five types of psychic duality are distinguished: bipolarity, bimodality, contrariety, dualism, and the coincidentia op–positorurn. Bipolarity is the basic division of the psyche into egoic and nonegoic (physico–dynamic) poles. Bimodality is the division of egoic functioning into active and receptive modes. Contrariety is the division of the nonegoic sphere into opposing sympathetic and parasympathetic systems. Dualism is the organization imposed upon the bipolar structure by primal repression. And the coincidentia opositorum is the condition of psychic integration that would emerge were dualism to be transcended and the bipolar structure (together with the bimodal and contrarietal structures) unified into a higher whole. 相似文献
77.
Concurrent access to two concentrations of orally delivered phencyclidine: effects of feeding conditions. 总被引:1,自引:1,他引:0
M E Carroll 《Journal of the experimental analysis of behavior》1987,47(3):347-362
Two experiments addressed the effects of food satiation and deprivation on oral self-administration of two concurrently available phencyclidine concentrations. In the first experiment, 8 rhesus monkeys self-administered either of two concentrations of phencyclidine ("PCP, angel dust") and water under concurrent fixed-ratio 16 schedules. One concentration was always held constant (0.25 mg/mL) while a series of other phencyclidine concentrations, ranging from 0 (water) to 1.0 mg/mL, was presented in a nonsystematic order. Initially the monkeys were tested while food satiated, and the procedure was then repeated during food deprivation. The monkeys usually selected the higher concentration within the first few minutes of the session, indicating that taste and/or other immediate postingestional effects were important factors. Contrary to a number of previous reports, there were no consistent differences across subjects in the mean number of liquid deliveries or mean drug intake (mg/kg) during food satiation and deprivation. However, for all monkeys the within-session time course of responding during food satiation consistently differed from that during deprivation. A second experiment assessed whether the failure to find consistent differences in drug intake during food satiation and deprivation had been due to the history of concurrent access to different phencyclidine concentrations or to the extended experience with phencyclidine under food-satiation conditions. Six additional monkeys (Group 2) were exposed to the phencyclidine self-administration procedure (during food satiation and deprivation) for the same length of time as the monkeys in Experiment 1 (Group 1), except they received only concurrent access to phencyclidine (0.25 mg/mL) and water. Both groups then received concurrent access to phencyclidine and water during five repeated cycles of food deprivation and satiation. There were also marked individual differences in Group 2: During food satiation, 2 of the monkeys' responding increased, 1 showed no change, and 3 decreased. Examination of a number of historical variables indicated that the greater the percentage of total sessions spent during food satiation with phencyclidine available (before these experiments began), the greater the amounts of phencyclidine consumed during food satiation and the smaller the differences in phencyclidine intake when the two feeding conditions were compared. 相似文献
78.
Effects of delayed conditioned reinforcement in chain schedules. 总被引:3,自引:3,他引:0
The contingency between responding and stimulus change on a chain variable-interval 33-s, variable-interval 33-s, variable-interval 33-s schedule was weakened by interposing 3-s delays between either the first and second or the second and third links. No stimulus change signaled the delay interval and responses could occur during it, so the obtained delays were often shorter than the scheduled delay. When the delay occurred after the initial link, initial-link response rates decreased by an average of 77% with no systematic change in response rates in the second or third links. Response rates in the second link decreased an average of 59% when the delay followed that link, again with little effect on response rates in the first or third links. Because the effect of delaying stimulus change was comparable to the effect of delaying primary reinforcement in a simple variable-interval schedule, and the effect of the unsignaled delay was specific to the link in which the delay occurred, the results provide strong evidence for the concept of conditioned reinforcement. 相似文献
79.
William Stout 《Psychometrika》1987,52(4):589-617
Assuming a nonparametric family of item response theory models, a theory-based procedure for testing the hypothesis of unidimensionality of the latent space is proposed. The asymptotic distribution of the test statistic is derived assuming unidimensionality, thereby establishing an asymptotically valid statistical test of the unidimensionality of the latent trait. Based upon a new notion of dimensionality, the test is shown to have asymptotic power 1. A 6300 trial Monte Carlo study using published item parameter estimates of widely used standardized tests indicates conservative adherence to the nominal level of significance and statistical power averaging 81 out of 100 rejections for examinee sample sizes and psychological test lengths often incurred in practice.The referees' comments were remarkably detailed and greatly enhanced the writeup and sensitized the author to certain pertinent issues. Discussions with Fritz Drasgow, Lloyd Humphreys, Dennis Jennings, Brian Junker, Robert Linn, Ratna Nandakumar, and Robin Shealy were also very useful.This research was supported by the Office of Naval Research under grant N00014-84-K-0186; NR 150-533, and by the National Science Foundation under grant DMS 85-03321. 相似文献
80.
Studies that have superimposed response-independent reinforcement (or reinforcers scheduled by contingencies placed on the absence of responding) upon conventional response-dependent schedules are reviewed. In general, providing alternative sources of reinforcement reduced response rates below the levels observed when alternative reinforcement was absent. However, response-rate elevation was sometimes found, particularly when rates of superimposed response-independent reinforcement were low. Superimposition of schedules providing reinforcers contingent on the absence of responding usually produced more severe response-rate decrements than superimposition of response-independent reinforcement. A variant of Herrnstein's equation, which assumes that some of the alternative reinforcers function as if they were delivered by baseline response-dependent source of reinforcement, is in qualitative agreement with the overall body of results obtained, and can predict both increases and decreases in response rate as resulting from superimposed reinforcers. 相似文献