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71.
This investigation examined the relationship between methylphenidate (MPH) and the learning and recall of paired associations by children with attention deficit disorder with hyperactivity (ADDH). Forty-five children with ADDH were randomly assigned to one of three groups (novel, partial mastery, and mastery learning) that varied in the amount of previous learning of paired associations and participated in a double-blind, placebo-control, repeated-measures-across-dose (crossover) design. Each child received four doses of MPH (5 mg, 10 mg, 15 mg, and 20 mg) and a placebo in a random, counterbalanced sequence. The results indicated that both the rate of acquisition and accuracy in learning paired associations were significantly, but differentially, affected by MPH dose and the degree of learning mastery. The implications of these results for psychopharmacological research and the monitoring of psychostimulant effects on children's learning performance in academic settings are discussed.The authors wish to acknowledge and express their sincere appreciation to the graduate and undergraduate student members of the Children's Learning Clinic.  相似文献   
72.
A group of 115 black male adolescents drawn from a clinically unselected birth cohort, half of whom were known to have had neurological soft signs at age 7, were examined at age 17 to determine the relation between soft signs and performance on standard tests of school achievement and sustained attention. Three signs measured at age 17-dysgraphesthesia, difficulties with rapid alternating movements (dysdiadochokinesis), and motor slowness—were related to lower concurrent and past IQ and to impaired performance on laboratory and paper-and-pencil measures of sustained attention. The relation between signs and the attentional measures remained significant after IQ was statistically controlled. The three age 17 soft signs as well as age 7 signs were related to impaired performance on standardized tests (age 17) of school achievement. Most of the relation between signs and school achievement could be accounted for by the variance signs shared with sustained attention. One sign, mirror movements, was unrelated to all other attentional and cognitive measures.The study was supported by center grant MH 306906 and research training grant 5 T32 MH 13043-13 from the National Institute of Mental Health, as well as by the City College and the City University Computing Centers. We thank Lillian Belmont and two reviewers for their critical comments on an earlier version of the paper. We dedicate this paper to the memory of Joseph Barmack.  相似文献   
73.
Semantic priming in a lexical decision task was investigated with concurrent pretarget and posttarget primes. The posttarget prime also served as a pattern mask of the lexical decision target. Forward priming is defined as the presence of a semantically related pretarget prime and an unrelated posttarget prime. Backward priming is defined as the presence of a semantically related posttarget prime and an unrelated pretarget prime. Forward and backward priming were compared both when the nonword foils were "legal" and when they were "illegal" with respect to English orthography. Predictions were derived for two general approaches to word recognition: spreading-activation and expectancy-set theories. Both approaches assume that word representations occupy distinct, nonoverlapping locations in memory. Backward-prime facilitation was equivalent to forward-prime facilitation when nonword foils were illegal; however, backward-prime facilitation was not significant when nonword foils were legal. These results challenge both approaches. The proposed solution uses semantic-space (distributed) representations that are functionally unitized by a resonant matching (verification) process.  相似文献   
74.
The problem of detecting instructional sensitivity (item basis) in test items is considered. An illustration is given which shows that for tests with many biased items, traditional item bias detection schemes give a very poor assessment of bias. A new method is proposed instead. This method extends item response theory (IRT) by including item-specific auxiliary measurement information related to opportunity-to-learn. Item-specific variation in measurement relations across students with varying opportunity-to-learn is allowed for.This paper was presented at the 1987 AERA meeting in Washington, DC. This research was supported by grant OERI-G-86-003 from the Office of Educational Research and Improvement, Department of Education. The author thanks Michael Hollis and Chih-fen Kao for valuable research assistance, and appreciates valuable comments made by an anonymous reviewer.  相似文献   
75.
The Additive Factor Method assumes that task performance is the sum of sequential and independent processes. We studied the duration of the central processes (memory search and decision) and the motor decision process in hyperactive and learning-disabled children under socalled divided attention and S-R compatibility conditions. It was found that the learning-disabled were impaired in memory search and decision processes whereas hyperactives were impaired in the motor decision process.The authors wish to thank L. Leertouwer for making the drawings.  相似文献   
76.
Some properties are discussed of regular polygons that may result from angular homeostatic processes in stable orbit. To characterize these homeostatic polygons we need to discuss the winding number, the sidedness (integer, fractional and irrational), multiplicity, envelopes, and density. A regular (i.e., equilateral, equiangular) polygon may be closed in one revolution about its unique center, in multiple revolutions, or not at all. A homeostatic polygon can be generated only if all vertices are included in a single polygon, which occurs if and only if the number of vertices and the number of revolutions required to complete the polygon are relatively prime. For the homeostatic polygon to have a finite number of sides (without repeating itself) the angle subtended by any two successive vertices at the center must be a rational multiple of 2. Biological implications of these properties are illustrated.  相似文献   
77.
Y Rich  M Brook  O Yechieli 《Adolescence》1989,24(94):433-438
Fifty-eight male and 66 female junior high school students were examined to determine their preferences for sex of counselor under personal/social and educational hypothetical counseling situations. Girls demonstrated a definite same-sex preference for both counseling situations, while boys preferred male counselors for personal/social counseling and had opposite-sex preferences for educational counseling. Implications of the findings are discussed in light of earlier contradictory results from research on college students.  相似文献   
78.
Acquired affective-evaluative value: conservative but not unchangeable   总被引:3,自引:0,他引:3  
In a previous study on Evaluative Conditioning it was found that unlike signal-learning, evaluative learning is resistant to extinction. In the present experiment we tried to replicate and corroborate this finding. In addition, we investigated the effectiveness of a counterconditioning procedure to alter acquired evaluative value. On a within-subject base (n = 30), it was found that the mere contingent presentation of neutral with (dis)liked pictures of human faces was sufficient to change the affective-evaluative tone of the originally neutral stimuli in (negative) positive direction. Next, we replicated the finding that an extinction procedure does not have any influence on the acquired evaluative value of the originally neutral stimuli, and this even in subjects fully aware of the extinction presentations. We demonstrated the effectiveness of a counterconditioning procedure to alter acquired evaluative value, and in addition, found some evidence that awareness of the counterconditioning manipulations is not a prerequisite for its effectiveness. The theoretical consequences of these findings are phrased in terms of a fundamental distinction between signal-learning and evaluative learning, and some important implications for the behavioral treatment of affective-emotional disorders are suggested.  相似文献   
79.
A new method is proposed for estimating factor means and factor covariances in a group of individuals selected on their observed scores. The selection variable is, for example, the total score on an admissions test. Given a factor model for the test items based on the group of test takers, we may be interested in the factor structure for those in the top quartile. The differences in factor means and covariances between this selected group and the full group gives useful information both on successful test performance and on test validity. The new method draws on the classic Pearson-Lawley selection formulas. It avoids the fallacy of factor analysis on the selected group, which would lead to incorrect estimates. The new method is applied to a simple factor structure model for the GMAT test. Although the majority of the GMAT items test verbal skills, it is found that a quantitative factor shows the greatest change in moving from average to top quartile test takers.  相似文献   
80.
Analyzed explanatory style across the life span. 30 Ss whose average age was 72 responded to questions about their current life and provided diaries or letters written in their youth, an average of 52 years earlier. A blind content analysis of explanatory style derived from these 2 sources revealed that explanatory style for negative events was stable throughout adult life (r = .54, p less than .002). In contrast, there appeared to be no stability of explanatory style for positive events between the same 2 time periods. These results suggest that explanatory style for negative events may persist across the life span and may constitute an enduring risk factor for depression, low achievement, and physical illness.  相似文献   
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