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921.
Rebecca Logsdon Larry Hochhaus Harold L. Williams O.H. Rundell Dale Maxwell 《Acta psychologica》1984,55(2):179-193
An experiment which employed each of 18 subjects in four days of testing was used to examine acute secobarbital dose treatment effects on choice reaction time in a Cooper and Shepard (1973) character recognition task. Manipulations of visual stimulus degradation, character difficulty, 180 degree rotation, and mirror-image reversal were included in order to evaluate the hypothesis that the drug affects performance by disrupting early stimulus input processing. The results indicate significant increases in the effect of secobarbital on reaction time and errors under conditions of visual stimulus degradation. The effects of the drug, however, were not changed by 180 degree rotation of the target character or by the other task variables. The results were interpreted to indicate that secobarbital impairs performance primarily by placing selective stress on hypothetical early encoding activities and that later processing operations (associated with use of an internal representation of the target character) are not affected by the drug. Strengths and weaknesses of the two-stage model of visual stimulus processing are discussed and implications of the model for future drug research are indicated. 相似文献
922.
The present study examined some previously reported relationships between drug use by adolescents and perceived attitudes and behaviors of their parents. An anonymous questionnaire was administered to the student body of an inner-city secondary school for difficult students. Relationships between parental use of drugs and adolescent use of the same drugs were moderate and roughly equivalent across drugs. However, parental use of marijuana was strongly related to the adolescent's use of other, harder drugs such as opiates, cocaine, amphetamines, and barbiturates. This finding is explained within the framework of Kandel's postulated stages of drug initiation. It points to a need for further study of parental influences, which may be increasingly problematic as more individuals who have grown up in our marijuana-accepting society become parents of adolescents. 相似文献
923.
Several inherent limitations to secondary school sex education program evaluations are: limited generalizability, lack of longitudinal research, and no clear consensus of program outcomes. With a Bureau of Health Education, Center for Disease Control study as the criterion for program outcomes, a study was undertaken to examine the immediate and long-term impact of sex education upon program participants. Two of the 20 schools in the CDC study identified as having exemplary sex education programs provided access to their students and alumni. Inventories which measured perceived achievement of 33 sex education outcomes were piloted for reliability and validity. Each inventory examined participant changes in knowledge, understanding of self, values, interaction skills, self-esteem, and fear of sex-related activities. Students were surveyed in school; alumni were surveyed through the mail. Response rates ranged from 30 to 100 percent for students and alumni at both schools. Overall there was no statistically significant difference between the perceptions of students and alumni as to achievement of investigated outcomes. Alumni responses at one school did, however, indicate some potentially weak areas of their school's program with respect to values and interaction skills outcomes. It appears that program impact may decrease with time. Thus, isolating and addressing the factors involved may be necessary. This would assist program planners and instructors to strengthen curricula and program activities in order to enhance the overall impact of sex education. The present study supports the notion that positive gains are achieved as a result of each school's sex education program, and these gains remained over time. 相似文献
924.
The relationship between the availability of visual information and attention demands during the production of a discrete motor act was examined. Subjects were required to move a linear slide a distance of 15 cm in both 150 and 600 msec conditions under three light manipulations, viz., light always on; light always terminated as movement began; or, subject was unsure as to whether light would stay on or terminate. A simple key press by the index finger of the opposite hand to a tone was used as a secondary task and a measure of attention demands. The light manipulation influenced attention demands on the rapid 150 msec movement such that more attention was demanded when the subject knew the light would terminate. No such attentional strategy differences were found with the slow 600 msec movement. These findings suggest that task constraints in the form of kinematic criteria, together with the perceived availability of visual information, contribute to determining attentional strategy in movement production. 相似文献
925.
926.
A comparison of the WISC-R and the Woodcock-Johnson Psycho-Educational Educational Battery (W-J) was made for children with regular and learning-disabled (LD) class placement. The W-J and Wechsler Intelligence Scale for Children-Revised (WISC-R) evidence low to moderate correlations and significant mean differences, indicating that the two tests are measuring somewhat different abilities to somewhat differing degrees. W-J—WISC-R correlations for the regular students exceed those of the LD students in the greater majority of the cases. Rank ordering of the WISC-R subtests and the W-J clusters indicate, as might be expected, that the LD students fare the worst in the WISC-R academic subtests (Arithmetic, Information and Vocabulary) and in the W-J academic clusters. More research needs to be conducted with the W-J before it should be adopted for use in the placement of exceptional children. 相似文献
927.
David P. Lindeman Henry A. Goodstein Arlene Sachs Clifford C. Young 《Journal of School Psychology》1984,22(1):111-117
The purpose of the present study was to evaluate the predictive validity of the Yellow Brick Road Test (YBRT) relative to performance in reading as measured by the Metropolitan Achievement Test (MAT). A full prediction-performance comparison matrix was employed to compare three different cutoff scores for the YBRT for the identification of “at-risk” children. Four hundred and fourteen kindergarten-aged children were administered the YBRT, 214 of whom were followed to the end of second grade. It was concluded that the YBRT is a moderately valid instrument for predicting the level of reading achievement in a population with a different average performance level from the normative sample. However, the results of this study failed to support the utility of the test author's suggested use of a score of 120 as the cutoff score. Finally, it is recommended that a prediction-performance comparison study be considered standard methodology for the evaluation of the validity and efficiency of screening instruments. 相似文献
928.
929.
Traditional strategies for determining whether a reinforcer schedule enhances the occurrence of an activity are reviewed and critically evaluated. A basic assumption underlying these strategies is that it is possible to isolate the effect of reinforcer intermittency on schedule induction. It is concluded that this is not, in fact, possible. An alternative approach is proposed that emphasizes the inductive effects of the reinforcer schedule as a unit and the effects of particular aspects of the reinforcer schedule (e.g., interreinforcer interval, repetition of the reinforcer, reinforcer magnitude). 相似文献
930.
Harzem P 《Journal of the experimental analysis of behavior》1984,42(3):385-395
In psychological studies individual differences that result in variability in data and thus mask the effects under investigation have been reduced or eliminated in two ways: (1) through the use of large numbers of subjects and statistical manipulations, or (2) through extensive and controlled studies of individual subjects. The latter, behavior-analytic, method is scientifically better because it permits identification of the variables that result in individual differences. This paper advocates the direct study of individual differences and personality rather than indirect study through experimental control procedures. Some data are presented showing that individual differences in response patterns have orderly characteristics. Extension of the experimental analysis of behavior to the study of individual differences and personality is likely to be important both scientifically and for the future growth of behavior analysis. 相似文献