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881.
Electromyographic (EMG) and temporal artery vasomotor activity was evaluated in three groups of headache patients (tension, migraine and combined) and nonheadache control subjects while in reclining, sitting and standing positions. Analysis of the EMG data revealed that at all measurement sites (bilateral frontalis, bilateral trapezius) the three headache groups demonstrated significantly higher levels than the nonheadache group but did not differ from each other. A secondary analysis of the trapezius EMG data revealed that a large percentage of headache patients had “normal” EMG levels in the reclining position but showed abnormalities in the sitting and standing positions. Analysis of the left temporal artery vasomotor activity revealed that all three headache groups vasoconstricted to a significantly greater extent than the nonheadache group in the sitting and standing positions. However, a diagnosis by position interaction was found for the right temporal artery with the migraine group demonstrating a unique pattern of activity.  相似文献   
882.
The validity of a test battery, organized by a theoretical framework of levels of language processing and production, was evaluated at the end of kindergarten and theend of first grade. At the end of kindergarten two levels of oral language, phonemic and lexical, and at the end of first grade three levels of oral language, phonemic, lexical, and text, were correlated with word decoding and reading comprehension. At the end of first grade, the combination of phonemic and lexical skills accounted for more variance in both word decoding and reading comprehension than either phonemic or lexical skills alone. The strength of the relationship between specific levels of oral language and specific component reading skills changed after formal reading instruction was introduced. Functional relationships were found between improvement in phonemic skills or lexical skills and improvement in word decoding. Partial correlations between two levels of oral language with a third partialed out (receptive or expressive task requirements held constant) provided evidence for three semiindependent levels of oral language—phonemic, lexical, and text. Because the battery has concurrent and construct validity, school psychologists can use it to monitor beginning readers in order to prevent reading disabilities due to subtle language dysfunctions.  相似文献   
883.
Two nested structural models were developed to determine whether test-session behaviors affect the manner in which intelligence is measured or whether their influence is related to the constructs being measured. Children’s test-session behaviors were assessed using the Guide to the Assessment of Test-Session Behaviors for the WISC-III and WIAT (GATSB; Glutting & Oakland, 1993) and intelligence was measured with the Wechsler Intelligence Scale for Children-Third Edition (WISC-III; Wechsler, 1991). Model 1 investigated relationships between test-session behaviors and the WISC-III’s four-factor solution by first evaluating the underlying factor structure of the instruments. Thereafter, this measurement model served as a baseline against which alternative models were compared. The alternative models considered the influence of test-session behaviors on: (a) the subtests used to measure the WISC-III’s constructs of intelligence, and (b) the actual constructs of intelligence. Model 2 explored similar relationships by considering only the WISC-III’s Verbal and Performance dimensions. Results indicate that test-session behaviors play a larger role influencing the mechanisms through which intelligence is measured than on the actual constructs of intelligence. Implications are discussed for clinical practice.  相似文献   
884.
In this article, we review literature relevant to multicultural issues in school-based consultation. Specifically, multicultural literature in the counseling and psychotherapy fields is presented as it relates to consultation. Ways in which culture may affect the consultant, consultee, and client are suggested. Because of the paucity of multicultural research in consultation and lack of major break-throughs in multicultural research as related to consultation, a conceptual framework related to the utility of multicultural issues is presented as a new paradigm for future investigations.  相似文献   
885.
This study employed a stimulus-class rating procedure to explore whether stimulus equivalence and stimulus generalization can combine to promote the formation of open-ended categories incorporating cross-modal stimuli. A pretest of simple auditory discrimination indicated that subjects (college students) could discriminate among a range of tones used in the main study. Before beginning the main study, 10 subjects learned to use a rating procedure for categorizing sets of stimuli as class consistent or class inconsistent. After completing conditional discrimination training with new stimuli (shapes and tones), the subjects demonstrated the formation of cross-modal equivalence classes. Subsequently, the class-inclusion rating procedure was reinstituted, this time with cross-modal sets of stimuli drawn from the equivalence classes. On some occasions, the tones of the equivalence classes were replaced by novel tones. The probability that these novel sets would be rated as class consistent was generally a function of the auditory distance between the novel tone and the tone that was explicitly included in the equivalence class. These data extend prior work on generalization of equivalence classes, and support the role of operant processes in human category formation.  相似文献   
886.
Response-contingent deliveries of oral pentobarbital maintained responding of 3 rhesus monkeys during daily 3-hr sessions. Deliveries of pentobarbital were arranged under nonindependent concurrent variable-ratio variable-ratio schedules. Responses to either schedule counted toward completion of both variable-ratio schedule requirements. This schedule is similar in some respects to conventional concurrent variable-interval variable-interval schedules, in which passage of time counts toward completion of the interval value on both schedules. Restricted nonindependent concurrent variable-ratio variable-ratio schedules were also studied. On that schedule, when a drug delivery was assigned to one spout, it had to be collected before responses on the opposite spout again counted toward completion of the schedule requirements. Relative reinforcer magnitude was varied by changing the drug concentration on one schedule while keeping the drug concentration constant on the other variable-ratio schedule. Under both types of concurrent variable-ratio schedules, the relative rate of responding corresponded to the relative drug intake. Unlike earlier studies of concurrent variable-interval variable-interval intravenous cocaine reinforcement, preference was proportionate to concentration, and exclusive preferences did not develop. The relationship between relative rate of responding and relative drug intake was well described by the generalized matching law.  相似文献   
887.
Groups of 8 experimentally naive rats were exposed during 8-hr sessions to resetting delay procedures in which responses on one lever (the reinforcement lever) produced water after a delay of 8, 16, 32, or 64 s. For rats in one condition, responses on a second (no-consequences) lever had no programmed consequences. For rats in another condition, responses on a second (cancellation) lever during a delay initiated by a response on the reinforcement lever prevented delivery of the scheduled reinforcer; responses on the cancellation lever at other times had no programmed consequences. Under both conditions and at all delays, most subjects emitted more responses on the reinforcement lever than did control rats that never received water emitted on either lever. At 8-s delays, both conditions engendered substantially more responding on the reinforcement lever than on the other lever, and performance closely resembled that of immediate-reinforcement controls. At delays of 16 and 32 s, however, there was clear differential responding on the two levers under the cancellation condition but not under the other condition. When the delay was 64 s, differential responding on the two levers did not occur consistently under either condition. These findings provide strong evidence that the behavior of rats is sensitive to consequences delayed by 8, 16, and 32 s, but only equivocal evidence of such sensitivity to consequences delayed 64 s. They also indicate that acquisition depends, in part, on the measure of performance used to index it.  相似文献   
888.
Letter series and number series tests, consisting of items based on identical rules, were administered in a counterbalanced design to 58 persons (46 women and 12 men) between the ages of 61 and 88 years to determine their relative efficacy (relative difficulty and acceptability) as measures of inductive/deductive reasoning ability. Results indicated that letter and number series tests, in which each item in one has a same-rule counterpart in the other, were not equivalent in regard to their relative difficulty or popularity among the elderly. The number series test was significantly (p 0001) easier and more popular than its letter series counterpart. Some of the implications of these findings for assessing reasoning ability in the elderly were specified.  相似文献   
889.
This study examines the accuracy of judgements of relative distance of traffic sounds (car and lorry) compared with nonattributed sounds (white noise). Adults judged whether sounds were comparatively nearer or further away in both conditions when decibel levels were the same and when decibel levels differed. Results indicated that judgement of relative distance is generally difficult and that such judgements are not based on loudness alone, particularly for traffic sounds. More errors were made when decibel levels were the same, indicating a reluctance to rely on loudness as an indicator of distance. Also more errors were made for traffic sounds. It was suggested that nonauditory criteria may be used in interpreting sounds, possibly including past experience and visual imagery. Finally, the implications of the results for road safety are discussed.  相似文献   
890.
Many of the topics of interest in the social and behavior sciences are often hierarchical or multilevel in nature. These multiple levels (e.g., individual versus group) create problems for researchers related to the choice of measurement and analysis. Recent innovations in statistical analysis have made it possible to account for the hierarchical nature of observations. Therefore, in this article we begin with a review of multilevel analysis techniques and discuss advances that have been made in the social sciences using multilevel models. Next, we summarize contemporary research specific to the organizational psychology literature that uses multilevel analysis. Possible applications for industrial and personnel psychology are then discussed. Guidelines for determining if multilevel analysis is appropriate for a given applied research project are provided. We conclude with a summary and call for increased use of multilevel analysis in industrial and personnel psychology.  相似文献   
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