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251.
252.
N-Methyl-D-aspartate (NMDA) receptor antagonists disrupt learning on a variety of tasks. Previous findings indicate that glucose, naloxone, and physostigmine ameliorate learning deficits produced by several treatments. The present experiment examines whether these agents also reverse the amnestic effects of NMDA receptor blockade. Mice were tested for spontaneous alternation performance in a Y-maze. The animals received either saline or the NMDA antagonist, NPC 12626 (35 mg/kg, IP), 50 min prior to testing and received an additional injection of saline, glucose, naloxone, or physostigmine 30 min prior to testing. NPC 12626 significantly decreased alternation scores. Glucose (250 mg/kg), physostigmine (0.01 mg/kg), and naloxone (1 mg/kg) reversed the effects of NPC 12626. Thus, impairments of learning after NMDA receptor blockade share with other amnestic conditions the susceptibility to attenuation by glucose, naloxone, and physostigmine. 相似文献
253.
Although visuoconstructive impairment has been reported in both Alzheimer's (DAT) and Huntington's (HD) disease, there is little knowledge concerning how this cognitive deficit differs quantitatively and qualitatively in these two progressive dementias. To address this issue, the present study compared performances on the Clock Drawing Test (CDT: command and copy) of 25 DAT patients, 25 equally demented HD patients, and 25 elderly normal controls (NC). In the command condition, both patients groups were significantly impaired compared to the NC group. Although there was no significant difference between DAT and HD patients' total quantitative scores, a qualitative error analysis revealed a number of dissociations between the two patient groups. Graphic difficulties, very common in HD patients, were virtually absent in DAT patients; in contrast, conceptual errors were almost exclusively seen in DAT patients and were related to the severity of their dementia. Perseveration and "stimulus-bound" responses were also more frequent in DAT patients, and both groups made visuospatial errors. In the copy condition, the DAT, but not the HD, patients evidenced a marked improvement in performance. These results indicate that while both DAT and HD patients have significant visuoconstructive difficulties even in the early stages of their disorders, the specific cognitive processes underlying their quantitative impairments are quite different. It is possible that the DAT patients' conceptual errors are yet another indicator of the deterioration of their semantic knowledge. 相似文献
254.
Remembering pictures: pleasure and arousal in memory. 总被引:17,自引:0,他引:17
M M Bradley M K Greenwald M C Petry P J Lang 《Journal of experimental psychology. Learning, memory, and cognition》1992,18(2):379-390
Incidental memory performance for pictures that varied along the affective dimensions of pleasantness and arousal was assessed. For both an immediate and delayed (1 year later) free-recall task, only the arousal dimension had a stable effect on memory performance: Pictures rated as highly arousing were remembered better than low-arousal stimuli. This effect was corroborated in a speeded recognition test, in which high-arousal materials encoded earlier in the experiment produced faster reaction times than their low-arousal counterparts. Pleasantness affected reaction time decisions only for pictures not encoded earlier. These results suggest that whereas both the dimensions of pleasantness and arousal are processed at initial encoding, long-term memory performance is mainly affected by arousal. 相似文献
255.
256.
This article describes a study conducted to identify the range of potential influences that a computer-assisted careers guidance system (PROSPECT (HE)) had on the functioning of organisations (careers services in higher education). Data from six institutions indicated that use of PROSPECT (HE) was associated with important and varied change within the organisations. It appears that when a careers service seeks opportunities for change, CACG systems can be an important catalyst for change in two respects: by providing a focal point for achieving previously established goals; or, as a consequence of system use, by making staff aware of the potential for new organisational goals. 相似文献
257.
B. Michael Ferencik Ph.D. 《Group》1992,16(2):113-124
The essential activity of group therapy consists of members taking an interest in each other by asking questions, showing concern, and conveying understanding. When members have not done this it has often been taken as a sign of resistance. A review of the research on helping suggests that there are four social factors that affect assistance giving in groups: 1) ambiguity-often people fail to give help because they are uncertain about who should give it, what should be done, and how it should be done; 2) often help is not given because of the way in which problems are presented; 3) the social comparisons that individuals make affect help-giving; and 4) there are costs associated with providing assistance. This discussion suggests that leaders can facilitate interaction among group members as teachers who clarify and as indirect helpers who redirect concerns back to group members. 相似文献
258.
Marilyn P. Safir Rachel Hertz-Lazarowitz Shoshanna BenTsvi-Mayer Haggai Kupermintz 《Sex roles》1992,27(9-10):439-453
Several studies have revealed teachers' asymmetric perceptions of girls and boys in their classes. The present research examines these effects on schoolchildren's own perceptions of the prominence of male and female peers in school relevant categories. A total of 147 (native born, Jewish middle class) second and sixth graders participated in the study. A questionnaire in two versions was prepared: One formulated in the masculine plural, habitually used in Hebrew as the generic plural for both sexes. The other in both masculine and feminine (optional he/she) plural, also admissible in Hebrew usage. Overall, students judged more boys as prominent, even more so in sixth grade. Subjects also pointed to same-sex peers as prominent. Surprisingly, the sex-optional formulation of the questionnaire did not decrease stereotyping perceptions. Results raise questions about the status of girls in school. Implications for girls' future as achievers in modern society are discussed. Furthermore, the effectiveness of language manipulation in Hebrew regarding sexist vs. nonsexist attitudes is put into question. 相似文献
259.
This study explored patterns emerging in videotaped sessions of group psychotherapy with seven outpatients of a large mental health facility. The 22 sessions spanned the 12th to 27th months of the group's existence. Group members had long histories (25–50 years) of symptoms characteristic of schizophrenia. Each session was rated on the Group Environment Scale. One session from a group in its earlier stages was also rated on the same instrument to give some indication of baseline patterns. Analyses of changes across the 15 months were not statistically significant. However, some GES subscales, including Cohesion, Independence, and Self-Discovery, showed relatively high mean levels across the 15-month period. These elevations are discussed as suggesting the codevelopment of orientations that have sometimes been viewed as incompatible and unattainable for schizophrenics. Interpreted clinically, the GES patterns help to elaborate recent findings about the relatively good success of long-term group therapy with such populations. The study, although merely suggestive, illustrates the potential for gleaning solid and clinically useful data from group psychotherapy research.The authors would like to thank Drs. Jill Rierdan, Nina Fieldsteel, Joseph Christy, and an anonymous reviewer for their suggestions, Kendra Bryant for serving as the reliability rater, and Janet Eltinge for her skilled videotaping. 相似文献
260.
Two experiments are reported which investigated how subject gender and time-of-day influenced the estimation of duration and
the perception of task-related mental workload. In the first experiment, 24 subjects performed a filled time-estimation task
in a constant blacked-out, noise-reduced environment at 0800h, 1200h, 1600h, and 2000h, respectively. In the second experiment,
12 different subjects performed an unfilled time estimation task in similar conditions at 0900h, 1400h, and 1900h. At the
termination of all experimental sessions, participants completed the NASA Task Load Index workload assessment questionnaire
as a measure of perceived mental workload. Results indicated that physiological response, reflected in body temperature change,
followed an expected pattern of sequential increase with time-of-day. However, estimates of duration and the perception of
mental workload showed no significant effects for time-of-day. In each of the experiments there were significant differences
in time estimation and mental workload response contingent on the gender of the participant. These results are interpreted
in light of the previous positive findings for circadian fluctuation in performance efficiency and the equivocal findings
of a gender difference in time estimation. A unifying account of these collective results is given based on gender by time-of-day
interactional effects.
An earlier version of this paper was presented at the 32nd Annual Meeting of the Human Factors Society, Anaheim, CA, October,
1988. 相似文献