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951.
Several researchers who have compared the performance of dyslexic and normal-reading children on a variety of different tasks have suggested that dyslexic children may have subtle deficits in the phonemic analysis of spoken as well as written language. Thus it is of interest to know how children who have extraordinary difficulty learning to read can perform explicity auditory-phonetic tasks. Seventeen dyslexic children (10 years of age) and a group of 17 controls were administered tests of identification and discrimination of synthesized voiced stop consonants differing in place of articulation. These were tests of the type used to study categorical perception in adults, adapted for use with young children. Significant differences between dyslexics and controls were found in both kinds of tasks; the pattern of identification and discrimination differences suggests an inconsistency in the dyslexics' phonetic classification of auditory cues. A significant relationship was found between reading level and speech discrimination.  相似文献   
952.
Currently, in the United States, redundancy counseling, dealing with jobless or displaced workers, is the exception rather than the rule in cases of plant closures. It is likely, however, that redundancy counseling will become more common in the future, as more U.S. manufacturers turn to production sharing. Indeed, it has been suggested that redundancy counseling might replace the traditional unemployment compensation system as a better method of dealing with unemployment in a rapidly changing, highly technological world.  相似文献   
953.
The purpose of this study was to illustrate the use of time-series analysis with long-term cardiovascular responding. Analyses of two successive 1000-minute mean blood pressure and heart-rate series in five chronically instrumented dogs showed that the autocorrelation function of the original series appeared highly nonstationary and that differencing the data produced a simple autocorrelation pattern which could be successfully modeled with stepwise autoregression. Evidence for reliable individual differences as well as change over sessions is presented and discussed.  相似文献   
954.
Marcel (1978) has shown that semantic priming can occur in the lexical-decision task even if the prime is masked to the point at which its presence cannot be detected. The purpose of the present experiments was to determine if primes that begin four or five spaces to the right of fixation can also produce semantic facilitation even though they are very difficult to recognize. Experiment 1 showed that facilitation did occur when the parafoveal primes used in the subsequent experiments were presented foveally. In Experiment 2, the primes were moved to the parafovea, but the task demands directed the subject’s attention toward the fovea. When subjects were ignoring the information presented to the parafovea (an allocation pattern that should correspond to that used during normal reading), neutral primes were just as effective as either semantically related or identical primes. In Experiment 3, the task demands were altered so that subjects were actively attending to the parafoveal primes. Although subjects were trying to process the primes, there was still no evidence that benefits could be derived from parafoveal primes. A final experiment showed that subjects given extensive practice with the materials will produce large amounts of identity and semantic priming. The results support the conclusion that readers can benefit little from the preprocessing of information in the parafovea unless that information can be supplemented with contextual expectations.  相似文献   
955.
Subjects heard a series of two-part melodies, in which each part was a random sequence of eight pitches (Experiment 1) or five pitches(Experiment 2) from the diatonic scale. The task was to rate each melody on how well the second part followed the first. It was predicted that the presence of symmetry between the two parts would increase the perception of good continuation. In Experiment 1, two symmetrical relat/lons—(itinversion) and (itretrograde)—yielded melodies that were more highly rated than the control melodies, which consisted of nominally (itdifferent) parts. A third symmetry, the (itretrograde inversion), did not enhance good continuation ratings. In Experiment 2, inversions and retrograde inversions were compared with control melodies, using shorter sequences and pitches with equal durations. Again, inversions, but not retrograde inversions, were significantly preferred. The results suggest that the aesthetic judgment of good continuation depends at least partially on a cognitive analysis of the relation between the melody parts. The positive symmetry effects are further discussed in relation to other studies of symmetry transformations in the contexts of both musical sequences and visual arrays.  相似文献   
956.
Subjective contours were compared with objective contours in their ability to facilitate performance in speeded tasks that required judging the position of a dot or the slope of a line segment relative to the contour. Subjective contours were found to reduce both reaction times and error rates for dot localization but not for the more difficult slope discrimination task. These results add to the growing body of evidence suggesting that subjective contours have functional properties similar to those of objective contours.  相似文献   
957.
The Ramey and Haskins intervention experiment succeeded in producing IQ gains at three years of age averaging about one standard deviation in young children who were selected for being at risk for subnormal intellectual development. The study is examined in terms of its consistency with other findings, the heritability of IQ, the g aspect of IQ, the simplex pattern of longitudinal interage mental test score correlations, mother-child IQ correlations, and criteria for establishing educationally and socially significant gains in intelligence defined as g rather than as a score on a particular test. Narrow transfer of training from cognitive intervention techniques to IQ test performance in early childhood, rather than enhancement of the g factor itself, is hypothesized as a cause of the typical fadeout of early IQ gains in later childhood.  相似文献   
958.
959.
Medication effects in the classroom: Three naturalistic indicators   总被引:2,自引:0,他引:2  
Hyperactive and comparison boys participated in 5-week summer enrichment programs that included classroom activities and structured assessments of peer interaction patterns. During the 3rd and 4th weeks of these programs, a double-blind, methylphenidate-placebo crossover design was implemented within the hyperactive group. Three heterogeneous indicators of everyday behaviors were obtained: number of negative incidents noted by staff, quality of handwriting, and number of times the teacher called the boys' names aloud in the classroom. Medication effects emerged for each of these indicators. When hyperactive boys were taking placebos, they were involved in more negative incidents, their handwriting was poorer, and their names were called more frequently than when the boys were taking methylphenidate. Interrelationships among the measures suggest moderate cross-situational generality of medication responsiveness. Discussion focused on the bandwidth of medication effects and the need to examine the social ramifications of child treatments.This research was supported in part by NIMH grant 29475 and NIDA grant 01070. We gratefully acknowledge the participation of the data coders and the many summer school staff. Special thanks go to Mike Berlin, Barry E. Collins, and Sharon Dotemoto. Methylphenidate and placebo were supplied by Ciba-Geigy, Summit, New Jersey.  相似文献   
960.
In recent years, several studies have been conducted in which the fluency of stutterers was compared with that of normal speakers. These investigations have been of two basic types, some involving objective measures of physiologic, aerodynamic, or acoustic features of the subjects' fluent speech signal, and others involving experiments performed in which listeners attempted to distinguish the fluency produced by stutterers from that generated by normal speakers. The body of literature pertaining to each of these two types of investigations is reviewed and interpreted. The interpretations offered are then developed in an effort to shed further light on both fluency and stuttering. Implications for further research, as well as for the evaluation, treatment, and post-therapy assessment of stutterers are drawn.  相似文献   
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