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231.
The light-emitting diode (LED) is becoming increasingly popular as a luminance source in behavioral research. We describe a simple, inexpensive LED driver circuit that produces luminances almost linearly proportional to an input voltage. Negative feedback provides a stable output. Unlike previous designs, the LED is ground referenced. 相似文献
232.
While several guidelines for avoiding sexist language in career materials have been published, little empirical evidence exists to support the assumption that sexist language in career information has deleterious effects on clients. The purpose of this study was to explore the effects of sex-biased language in occupational information on subject interest and attitudes regarding gender appropriateness of occupations. Eighth-grade students read occupational briefs on two occupations presented in either neutral, female-biased, or male-biased language. Results showed a nonsignificant language effect and a significant sex difference in interest in the occupations. A significant three-way interaction (language by subject sex by occupation) was found for gender-appropriateness ratings. The findings, together with previous research, suggest that language may have little impact on specific occupational interests, but may affect other career attitudes related to interests. 相似文献
233.
234.
A lie detection instrument, the Psychological Stress Evaluator, has been reported by the manufacturer as being capable of quantifying changes in the degree of “stress” as reflected by a subject's voice. Speech pathologists might consider the use of the instrument in clinical and research activities concerning the stutterer's emotional (stress) reaction to stuttering.To test the validity of the instrument, four stutterers and four normal speakers were recorded while making consecutive telephone calls. Randomized recordings were analyzed by a company trained technical to determine the degree of stress for each speech sample.Results indicated that both groups had a significant reduction of stress from the first to the fourth telephone call. However, the groups did not differ in the degree of stress during the ordered series of calls. Due to the inability of the Psychological Stress Evaluator to differentiate between the groups, the validity of the instruments is questioned. 相似文献
235.
236.
William F. Chaplin 《Journal of personality》1991,59(2):143-178
237.
Previous research (Hall, Scholnick, & Hughes, 1987) suggested that cognitive word meanings denote six increasingly abstract and complex cognitive processes. In this paper, we further investigated two interrelated aspects of this framework. A set of 36 conversations with children aged 4:5 to 5 provided the data. In Study 1, issues related to the optimal ordering of levels were examined by comparing the original sequence with a restructured model. In Study 2, the hypothesis that, in addition toknow, other polysemous cognitive internal state words would be hierarchically organized was tested. The findings lent support to the restructured model, but rejected the hypothesis that polysemous words within the domain were characterized by equivalent,hhierarchically organized levels. We conclude by proposing that cognitive internal state words were related by complementarity of levels rather than equivalence.The research on which this paper is based was supported by a grant from the Carnegie Corporation of New York to William S. Hall. Data analysis was supported by the Computer Science Center at the University of Maryland, College Park. 相似文献
238.
Two experiments were performed that involved an initial word-identification task in which the acoustic signal was degraded by either 50% or 60% compression of the recorded words. A control group was tested at the original recording rate (0% compression). The compression manipulation was successful in increasing the number of identification errors. During the second stage of the experiments, words were read at a normal rate. In Experiment 1, the subjects indicated whether each word had appeared on the prior list, and in Experiment 2, the subjects estimated the number of times each word had been read on the prior list. The false-negative rate decreased and frequency ratings increased as a function of the number of prior presentations (one, two, or three) of the target words. The most interesting result was that the effect of repetitions was present even for words that had been misperceived. 相似文献
239.
Michael J. Balthazor Richard K. Wagner William E. Pelham 《Journal of abnormal child psychology》1991,19(1):35-52
There appear to be beneficial effects of stimulant medication on daily classroom measures of cognitive functioning for Attention Deficit Disorder (ADD) children, but the specificity and origin of such effects is unclear. Consistent with previous results, 0.3 mg/kg methylphenidate improved ADD children's performance on a classroom reading comprehension measure. Using the Posner letting-matching task and four additional measures of phonological processing, we attempted to isolate the effects of methylphenidate to parameter estimates of (a) selective attention, (b) the basic cognitive process of retrieving name codes from permanent memory, and (c) a constant term that represented nonspecific aspects of information processing. Responses to the letter-matching stimuli were faster and more accurate with medication compared to placebo. The improvement in performance was isolated to the parameter estimate that reflected nonspecific aspects of information processing. A lack of medication effect on the other measures of phonological processing supported the Posner task findings in indicating that methylphenidate appears to exert beneficial effects on academic processing through general rather than specific aspects of information processing. 相似文献
240.
William E. MacLean Jr. David N. Ellis Holly N. Galbreath Leslie F. Halpern Alfred A. Baumeister 《Journal of abnormal child psychology》1991,19(3):319-330
The developmental course of rhythmic motor behavior was followed longitudinally for three groups of preambulatory children — normally developing, Down syndrome, and those with profound motor impairment. The groups differed in chronological age but were comparable with respect to motor age. The motor impaired subjects displayed significantly less rhythmic motor behavior than the nondisabled and Down syndrome groups. In comparing particular subtypes of rhythmic motor behavior, differences were found in both the average number of bouts and duration of subtypes among the groups. Longitudinal analyses of the data over the entire observation period revealed that the rhythmic motor behavior of the children with Down syndrome was more similar to that exhibited by the nondisabled children than was the rhythmic motor behavior of the children with motor impairment. However, there was considerable variability among the groups in several particular subtypes.This research was supported by grants from the National Institute of Child Health and Human Development (HD 17650 and HD 07226).The authors acknowledge the assistance of Robert E. Arendt, Grant Youngquist, Michael Hohn, and Charles Lowitzer in obtaining the observational data and thank the families of the subjects for their enthusiasm and dedication to the project.This study was presented at the 23rd Annual Gatlinburg Conference on Research and Theory in Mental Retardation and Developmental Disabilities, April 21, 1990. 相似文献