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151.
H.G. Wells warned, in 1895, not to allow economic injustices to become so acute that they ultimately transform human biology. Wells's warning is all the more pertinent today as society contemplates the use of biotechnologies to manipulate or "enhance" the human genome.  相似文献   
152.
This article examines whether various cognitive abilities are associated with symptoms of ADHD. Cognitive ability is conceptualized using Cattell-Horn-Carroll (CHC) theory as measured using the Woodcock-Johnson Tests of Cognitive Ability (3rd ed.). This article also examines whether test session behavior mediates the association between cognitive ability and ADHD. Participants are children ages 6 to 12 with (n= 33) and without (n= 19) ADHD. Results show that inattentive symptoms of ADHD are significantly related to the CHC ability of processing speed above and beyond the effect of test session behavior. Symptoms of ADHD (both inattention and hyperactivity/impulsivity) are also significantly associated with visual spatial processing, but this is completely mediated by test session behavior. It is concluded that inattentive symptoms of ADHD are associated with slower processing speed and that this relationship is not explained by test session behavior.  相似文献   
153.
Response time (RT) generally slows with aging, but the contribution of structural brain changes to this slowing is unknown. We used voxel-based morphometry (VBM) to determine gray matter (GM) and white matter (WM) brain volumes in 9 middle-aged adults (38–58 years old) and 9 seniors (66–82 years old). We correlated brain volumes with RT assessed in both a simple visual stimulus-response task and a visual continuous recognition memory task. No GM correlations with simple RT were significant; there was one WM correlation in the right fusiform gyrus. In the memory task, faster RT was correlated (p<.05, corrected) with less GM in the globus pallidus, the parahippocampus, and the thalamus for both groups. Several Brodmann areas (BA) differed between the groups such that in each area, less GM was correlated with slower RTs in the middle-aged group but with faster RTs in the senior group (BAs 19, 37, 46, 9, 8, 6, 13, 10, 41, and 7). The results suggest that individual differences in specific brain structure volumes should be considered as potential moderating factors in cognitive brain imaging studies.  相似文献   
154.
Statistical methods designed for categorical data were used to perform confirmatory factor analyses and item response theory (IRT) analyses of the Fear of Negative Evaluation scale (FNE; D. Watson & R. Friend, 1969) and the Brief FNE (BFNE; M. R. Leary, 1983). Results suggested that a 2-factor model fit the data better for both the FNE and the BFNE, although the evidence was less strong for the FNE. The IRT analyses indicated that although both measures had items with good discrimination, the FNE items discriminated only at lower levels of the underlying construct, whereas the BFNE items discriminated across a wider range. Convergent validity analyses indicated that the straightforwardly-worded items on each scale had significantly stronger relationships with theoretically related measures than did the reverse-worded items. On the basis of all analyses, usage of the straightforwardly-worded BFNE factor is recommended for the assessment of fear of negative evaluation.  相似文献   
155.
These cancer genetic counseling recommendations describe the medical, psychosocial, and ethical ramifications of identifying at-risk individuals through cancer risk assessment with or without genetic testing. They were developed by members of the Practice Issues Subcommittee of the National Society of Genetic Counselors Cancer Genetic Counseling Special Interest Group. The information contained in this document is derived from extensive review of the current literature on cancer genetic risk assessment and counseling as well as the personal expertise of genetic counselors specializing in cancer genetics. The recommendations are intended to provide information about the process of genetic counseling and risk assessment for hereditary cancer disorders rather than specific information about individual syndromes. Key components include the intake (medical and family histories), psychosocial assessment (assessment of risk perception), cancer risk assessment (determination and communication of risk), molecular testing for hereditary cancer syndromes (regulations, informed consent, and counseling process), and follow-up considerations. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a client.  相似文献   
156.
157.
Self-help and psychoeducation have been identified as effective methods for delivering treatment, yet not everyone benefits from these brief interventions. Therefore it is clinically and economically useful to identify who is likely to require more intensive assistance. This paper develops a prognostic scale which predicts who will recover from panic attacks and who will require more assistance. Method: Random regression models were used to evaluate the relationship between predictive variables, baseline severity, and the rate of improvement in 117 people with DSMIV panic attacks who participated in a trial of a psycho-educational booklet, a self-help workbook, and brief group CBT over a 9-month period. ROC analysis was used to choose cut-off points on a scale made up of significant predictors. Results: Panic disorder and agoraphobia symptom measures were predicted by baseline social anxiety, and general mental health. There was no significant effect on the outcome for baseline depression or anxiety sensitivity. While general mental health (SF12 Mental Component scores) was predicted by the age at first panic attack, neuroticism, panic disorder and/or agoraphobia symptoms and a positive screen for alcohol use disorders. A prognostic scale based on simple additive scoring was equivalent to standard scores and significantly better than chance at predicting who would recover and who required face-to-face therapy. Conclusions: The prognostic scale may be used to guide the choice of psychoeducation, self-help or face-to-face therapy as the first step in stepped care.  相似文献   
158.
This study addressed the role of proprioceptive and visual cues to body posture during the deployment of tactile spatial attention. Participants made speeded elevation judgments (up vs. down) to vibrotactile targets presented to the finger or thumb of either hand, while attempting to ignore vibrotactile distractors presented to the opposite hand. The first two experiments established the validity of this paradigm and showed that congruency effects were stronger when the target hand was uncertain (Experiment 1) than when it was certain (Experiment 2). Varying the orientation of the hands revealed that these congruency effects were determined by the position of the target and distractor in external space, and not by the particular skin sites stimulated (Experiment 3). Congruency effects increased as the hands were brought closer together in the dark (Experiment 4), demonstrating the role of proprioceptive input in modulating tactile selective attention. This spatial modulation was also demonstrated when a mirror was used to alter the visually perceived separation between the hands (Experiment 5). These results suggest that tactile, spatially selective attention can operate according to an abstract spatial frame of reference, which is significantly modulated by multisensory contributions from both proprioception and vision.  相似文献   
159.
The present study examined performance during 3 hr. of simulated sentry duty with and without the intermittent administration of low-level sensory stimuli (odor or vibration). For odor and control conditions, target-detection latency increased steadily over the course of the 3-hr. session. Administration of a tactile stimulus reduced the increase in detection latency compared to that found in odor and control conditions. For all conditions, there were no significant differences in target-detection frequency, shot accuracy, or friend-foe discrimination. Across all conditions, restlessness (motor activity) increased significantly the first hour and remained elevated for the rest of the session. Subjective measures of workload (NASA-TLX) indicated that the 3-hr. task rated high on physical demand, mental demand, frustration, and overall workload. These findings suggest that the intermittent delivery of a clearly detectable tactile stimulus can reduce reaction-time decrements that occur as time on task increases.  相似文献   
160.
Hamel R  Panicola M 《America》2004,190(14):6-13
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