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101.
102.
Despite speculation that sucrose consumption affects behavior, little empirical information is available. Accordingly, this study investigated the effect of sucrose consumption on the behavior of eight preschool children. Children were tested individually using a double-blind, crossover design. On separate mornings each child received 6 ounces of juice, sweetened on one morning with sucrose and on the other with an artificial sweetener. Children were observed for 90 minutes following the drinks, alternating between 15-minute sessions of work on structured tasks and 15-minute sessions of free play. Following the sucrose drink the children showed a decrement in performance in the structured testing situation, and they demonstrated more inappropriate behavior during free play. These differences in behavior were most pronounced approximately 45 to 60 minutes after the drinks. Thus, the study provides objective evidence in young children of a rather subtle, yet significant, time-dependent behavior effect of sucrose ingestion.This research was funded in part by grants from the General Research Grants Committee, University Hospital, Boston University Medical Center, and from the University of Connecticut Research Foundation. The project was conducted at the Clinical Research Center, Massachusetts Institute of Technology (National Institute of Health/General Clinical Research Center Grant 5M01-RR00088-20). We would like to express our appreciation to the many staff members of the Clinical Research Center for their extensive cooperation in helping us to plan and carry out this study, and to the director and staff of Technology Children's Center for their assistance in helping us to reach interested families. We also would like to thank the parents and children who participated in the study. Portions of this paper were presented at the annual meeting of the American Psychological Association, Toronto, August 1984.  相似文献   
103.
The ability to think of a previously studied item has often been shown to be impaired when, in one way or another, the extraitem context is changed from study to test. In a series of five experiments, such impairment is induced in a somewhat different way. A fragment (e.g. r-i--rop) of a just-studied word (raindrop) is shown to be less readily completed if it is presented bit by bit (r------p, r----r-p, r-i--r-p, r-i--rop) rather than all at once (Experiments 1, 3, 4, and 5). No such effect is found if the word has not been studied beforehand (Experiments 2, 3, 4, and 5). This pattern of results occurs even when fragments of studied and nonstudied words occur in the same test and under conditions in which subjects cannot tell whether a given fragment is of a studied or nonstudied word (Experiments 4 and 5). In addition, for words that have been studied beforehand, the impairment is shown to increase systematically with the number of steps involved in the presentation of the word fragment (Experiment 3) and also to persist when the time allowed for completion of the final version of the fragment is increased from 4 s to a full minute (Experiment 5).  相似文献   
104.
Although single-subject research techniques are relevant and valuable to counselors, analyzing change by graphs alone is open to major sources of error. The author discusses these sources and explores the issues of serial dependency, unreliability of graphs, interjudge disagreement on graphed data, and the use of a more reliable statistical procedure (the time-series statistic) with relevance to the counselor in the field.  相似文献   
105.
Psychopathology and symptom patterns were studied in 60 former prisoners-of-war (POWs) by administering standardized tests including the Minnesota Multiphasic Personality Inventory (MMPI), an adjustment problem checklist, and a structured clinical interview. Most POWs showed marked psychological impairment, but modal profile analysis identified two prototypic MMPI patterns, which differed in pervasiveness and type of psychopathology. Profile subtypes were defined by unique clusters of clinical symptoms and differed in confinement stress severity. The typology of symptoms argues against a homogeneous conceptualization of stress-induced disorders and suggests the need for definition of the severity and subtype of stress phenomena and individual difference factors in responding to trauma.  相似文献   
106.
The purpose of this study was to provide age-comparative evidence of social cognitive reasoning in adulthood, as mediated by the emotional saliency of tasks tapping postformal reasoning. Specifically, the tasks focused on the ability to resolve discrepant accounts of the same event sequence. It was assumed that less mature thinking may be more evident in reasoning contexts in which emotional factors play a major role. A postformal coding scheme was used to assess levels of reasoning in an interpersonal context. Tasks were administered to 60 subjects--adolescents and young and middle-aged adults. Measures of formal operations, ego level, and verbal ability were also administered. An interaction was found between age and degree of emotional saliency of the task for reasoning level. Specifically, adolescents performed less well on tasks higher in degree of emotional saliency. In addition, developmental differences in postformal reasoning as a function of age and ego level were found.  相似文献   
107.
Fluid intelligence belongs to that cluster of intellectual abilities evincing aging loss. To examine further the range of intellectual reserve available to aging individuals and the question of replicability in a new cultural and laboratory setting, 204 healthy older adults (mean age = 72 years; range = 60-86) participated in a short-term longitudinal training study. For experimental subjects, 10 sessions consisted of cognitive training involving two subability tests (Figural Relations, Induction) of fluid intelligence. The pattern of outcomes replicates and expands on earlier studies. Older adults have the reserve to evince substantial increases in levels of performance in fluid intelligence tests. Transfer of training, however, is narrow in scope. Training also increases accuracy of performance and the ability to solve more difficult test items. Difficulty level was estimated in a separate study, with a comparable sample of N = 112 elderly adults. Future research is suggested to examine whether intellectual reserve extends to near-maximum levels of performance.  相似文献   
108.
This study evaluated the relative efficacy of long (1 minute) and short (15 seconds) durations of negative practice for reducing self-stimulatory leg pounding of a traumatically brain-injured adult. In individual social skill training classes, long negative practice and short negative practice were administered concurrently in an alternating treatments design. Generalization of treatment effects outside of training sessions was assessed during the client's lunch period. The results revealed that both durations of negative practice were equally effective in reducing leg pounding during training sessions. However, the effects of training did not generalize to settings in which the practice contingency was not enforced. Pounding was more frequent and negative practice somewhat less effective during periods of high social stimulation.  相似文献   
109.
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   
110.
Relaxation-induced anxiety: mechanisms and theoretical implications   总被引:1,自引:0,他引:1  
Literature evidence documenting the occurrence of relaxation-induced anxiety is reviewed, and several hypothesized mechanisms to explain the phenomenon are discussed. Possible avenues for circumventing the problem in therapy are offered. Finally, a theoretical model is presented wherein the phenomenon is viewed with a broader framework designed to explain the development and maintenance of the more generalized anxiety disorders. That framework emphasizes the emergence of fear of somatic anxiety cues and fear of loss of control from more fundamental interpersonal anxieties.  相似文献   
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