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71.
Sustained attention in children at risk for schizophrenia: Findings with two visual continuous performance tests in a new sample 总被引:1,自引:0,他引:1
J. Rutschmann Barbara Comblatt L. Erlenmeyer-Kimling 《Journal of abnormal child psychology》1986,14(3):365-385
In partial replication of an earlier study, 35 children at high risk for schizophrenia, 25 children at high risk for affective disorder, and 53 normal control children from a new sample of 7- to 12-year-old subjects were tested with two new visual continuous performance tests. Response levels and intrasubject variability were analyzed separately. Multivariate analyses on factor scores derived from response levels indicate that "groups" is a significant predictor for a factor reflecting discriminability (or sensitivity) for the more difficult of these tests but not for the less difficult one, and that high risk for schizophrenia is associated with lower performance. Factor scores and multiple regression analyses were used to dichotomize subjects as to whether or not they are low performance outliers. A significantly larger proportion of subjects from the high risk for schizophrenia group than from the control groups were low performance outliers. Among subjects that developed psychopathology in adolescence, subjects at high risk for schizophrenia were more likely to have contributed low performance outliers early during childhood. 相似文献
72.
Though the term “new technology” is widely used and discussed, there has been very little systematic study of attitudes to
technology and their relation to other beliefs and group memberships. This article describes an initial investigation into
the nature of attitudes towards new technology (n=534 undergraduates) and demonstrates that, as yet, these attitudes are only weakly structured and are not fully integrated
with other social beliefs. General evaluations of the benefits of technological advance appear to be almost unrelated to beliefs
about the inevitability of these advances or the desire to acquire training to deal with them. Contrary to popular expectations,
evaluations of video games are unrelated to other beliefs about technology while other social beliefs are, as yet, only weakly
integrated with these attitudes. This study also identifies gender differences in the assessment of potential benefits and
highlights other differences attributable to academic group memberships. These finding are discussed with reference to the
literature on sex-role stereotyping and group socialization processes. 相似文献
73.
Factors affecting spontaneous alternation behavior (SAB) in animals, for example, age, gender and species studied; type of
apparatus and cues employed; and neuro-anatomical, neuro-chemical and motivational status of the organism, were reviewed.
Despite a myriad of experiments showing interesting main effects of such variables, little research has been performed assessing
the interactive affects of these factors on alternation behavior. For example, psychologists test rats in central nervous
system (CNS) lesion studies, whereas psychopharmacologists tend to assess SAB in mice. Most importantly, studies have not
been reported investigating the possible interactions among species, brain lesions and drugs. This is an unfortunate omission
since several important alternation models include propositions relating to cholinergic and/or serotonergic coding in the
hippocampus. Examination of behavioral studies revealed the primary cue for alternation among invertebrates to be body turn,
whereas vertebrates rely primarily on directional and odor cues. Reference to the seeking of stimulus change remains the most
compelling motivational account of why animals manifest this ubiquitious and reliable behavior pattern.
This review and the unpublished studies were supported by Research Grants MH16962, MH21288, and MH36491 from the National
Institute of Mental Health and the Wake Forest University Research and Publication Fund. 相似文献
74.
Inpatient Multimodal Therapy (imt) is a residential treatment program, lasting a maximum of 36 weeks, for patients with severe neurotic symptoms. A group of
44 chronic obsessive-compulsive patients and a group of 40 chronic phobic patients were treated in order to assess the outcome
and the process of treatment and to identify prognostic factors associated with the effect. At follow-up—on average, eight
months after discharge—it was found that 60% had improved, 32% had remained the same, and 8% had deteriorated, indicating
that, in general, the treatment was beneficial. That these effects were long-lasting is supported by the fact that, at follow-up,
78% of all patients were no longer receiving treatment, 18% were receiving outpatient or day treatment, and 4% were receiving
inpatient treatment. Phobic patients appear to have gained more from the multimodal approach than did obsessive-compulsive
patients, as indicated by the fact that the severity of symptoms decreased as they improved in rational thinking, assertiveness,
and arousal. By contrast, obsessive-compulsive patients relapsed more than phobic patients did. This was attributed to the
fact that the former gained less from the rational-emotive training, denied problems with assertiveness, and did not practice
the acquired relaxation skills. It further appeared that a favorable outcome could be induced in patients who (1) expressed
relatively mild symptoms in this otherwise severe group, (2) reported relatively few additional complaints, (3) could clearly
indicate interpersonal problems, and (4) did not use psychotropic drugs. These prognostic factors are so widespread that not
much weight can be ascribed to them. Yet they are useful for indication ofimt until better predictors are found. 相似文献
75.
This article is based on a review of recent literature on “computing stress”; that is, on the psychological stress effects
of working with computer systems. Current research into the sources of computer-related stress has tended to concentrate on
those employees who operate Visual Display Units (VDUs), either on a full-time professional basis as word-processor (WP) operators,
data-entry clerks, secretaries, or those dealing with enquiries from the public; or employees who use the VDU irregularly
as part of their other duties. A few studies have looked at specific occupation groups, such as printers (Kalimo & Lepp?nen,
1985), information technology professionals (programers and analysts), process workers, and college students (Sproull, Kiesler,
& Zubrow, 1984). Generally, however, research has been carried out on office workers, more often women, carrying out administrative
tasks. An attempt is made to identify those potential work-related stressors that have been isolated by these studies, and
also included are criticisms of the general methodologies used in many of them.
The terms “visual display unit,” “visual display terminal,” VDU, VDT, and “terminal” are used interchangeably. 相似文献
76.
Brief presentations of letter arrays were probed by bar markers within or outside the fovea after various time delays. Figural
information presented to the foveal region was retained better under a photopic condition than information in the parafoveal
region, but under a scotopic condition parafoveal information demonstrated superior retention. However, decay rates over time
of all functions were similar, demonstrating that figural information in the rods and cones decays at similar rates. 相似文献
77.
Two experiments investigated the nature of the code in which lip-read speech is processed. In Experiment 1 subjects repeated words, presented with lip-read and masked auditory components out of synchrony by 600 ms. In one condition the lip-read input preceded the auditory input, and in the second condition the auditory input preceded the lip-read input. Direction of the modality lead did not affect the accuracy of report. Unlike auditory/graphic letter matching (Wood, 1974), the processing code used to match lip-read and auditory stimuli is insensitive to the temporal ordering of the input modalities. In Experiment 2, subjects were presented with two types of lists of colour names: in one list some words were heard, and some read; the other list consisted of heard and lip-read words. When asked to recall words from only one type of input presentation, subjects confused lip-read and heard words more frequently than they confused heard and read words. The results indicate that lip-read and heard speech share a common, non-modality specific, processing stage that excludes graphically presented phonological information. 相似文献
78.
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
79.
80.
Glynis M. Breakwell Barbara Harrison Carol Propper 《British Journal of Guidance & Counselling》1984,12(2):132-140
Evidence of the effects of duration of unemployment and gender upon the psychological response to unemployment is reviewed. It is suggested that many of the apparent contradictions in this evidence can be resolved by reference to situational factors which shape how stressful unemployment is for a particular individual. The study reported tested the effects of a stressful period of unemployment on the psychological well-being, self-esteem and life-satisfaction of young people. No sex differences in response to unemployment were found, and this is explained in terms of the similarity of their experiences. The relevance of these findings for counselling the unemployed is discussed. 相似文献