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981.
Raz A Landzberg KS Schweizer HR Zephrani ZR Shapiro T Fan J Posner MI 《Consciousness and cognition》2003,12(3):332-346
Recent data indicate that under a specific posthypnotic suggestion to circumvent reading, highly suggestible subjects successfully eliminated the Stroop interference effect. The present study examined whether an optical explanation (e.g., visual blurring or looking away) could account for this finding. Using cyclopentolate hydrochloride eye drops to pharmacologically prevent visual accommodation in all subjects, behavioral Stroop data were collected from six highly hypnotizables and six less suggestibles using an optical setup that guaranteed either sharply focused or blurred vision. The highly suggestibles performed the Stroop task when naturally vigilant, under posthypnotic suggestion not to read, and while visually blurred; the less suggestibles ran naturally vigilant, while looking away, and while visually blurred. Although visual accommodation was precluded for all subjects, posthypnotic suggestion effectively eliminated Stroop interference and was comparable to looking away in controls. These data strengthen the view that Stroop interference is neither robust nor inevitable and support the hypothesis that posthypnotic suggestion may exert a top-down influence on neural processing. 相似文献
982.
983.
In three experiments, we investigated the influence of the overt performance of signs on memory. Deaf and hearing participants
studied lists of action phrases (Experiment 1) or nouns (Experiment 2) under standard verbal instruction, under the instructions
to sign the verbal phrase, to symbolically perform the denoted action, or to carry out a prototypical action corresponding
to each noun. Higher recall and recognition performances were observed when actions were performed than in the verbal encoding
condition, and signing was as effective for memory as was enactment. Thus, overt signing can induce an enactment effect. In
contrast, Experiment 3 demonstrated that performing an unrelated action did not. A unique but unrelated action was not memory
efficient. 相似文献
984.
Profile subtypes, based on the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) factor index scores, were examined in a sample of 166 patients with traumatic brain injury (TBI) by means of a two-stage clustering procedure. Three reliable subtypes were found that were differentiated primarily by level of performance across all factor index scores, although each of them demonstrated a relative weakness on the Processing Speed index. These subtypes were then validated on the basis of demographic variables, injury parameters, and additional psychometric measures that had not been included in the clustering procedures. The results indicated that performance on the WAIS-III after TBI was affected by both injury severity and level of education. It is concluded that there is no unique "signature" profile on the WAIS-III after TBI, except that a relative strength on the Processing Speed index is uncommon with this condition. 相似文献
985.
Mizuno M Yamada K He J Nakajima A Nabeshima T 《Learning & memory (Cold Spring Harbor, N.Y.)》2003,10(2):108-115
The N-methyl-D-aspartate (NMDA) receptors are involved in long-term potentiation (LTP), and are phosphorylated by several tyrosine kinases including a Src-family tyrosine kinase Fyn. Brain-derived neurotrophic factor (BDNF) is a neurotrophin, which also enhances hippocampal synaptic transmission and efficacy by increasing NMDA receptor activity. Here, we show that Fyn is a key molecule linking the BDNF receptor TrkB with NMDA receptors, which play an important role in spatial memory formation in a radial arm maze. Spatial learning induced phosphorylation of TrkB, Fyn, and NR2B, but not NR2A, in the hippocampus. Fyn was coimmunoprecipitated with TrkB and NR2B, and this association was increased in well-trained rats compared with control animals. Continuous intracerebroventricular infusion of PP2, a tyrosine kinase inhibitor, in rats delayed memory acquisition in the radial arm maze, but PP2-treated animals reached the same level of learning as the controls. The phosphorylation of Fyn and NR2B, but not TrkB, was diminished by PP2 treatment. Our findings suggest the importance of interaction between BDNF/TrkB signaling and NMDA receptors for spatial memory in the hippocampus. 相似文献
986.
Effects of environmental enrichment on spatial memory and neurochemistry in middle-aged mice 总被引:7,自引:0,他引:7 下载免费PDF全文
Frick KM Stearns NA Pan JY Berger-Sweeney J 《Learning & memory (Cold Spring Harbor, N.Y.)》2003,10(3):187-198
The present study compared the effects of environmental enrichment on spatial memory, glutamic acid decarboxylase (GAD) activity, and synaptophysin levels in middle-aged male and female mice. Prior to testing, a subset of 18-month-old male and female C57BL/6 mice was housed with two to three toys and a running wheel in the home cage for up to 29 d. Adult mice (7 mo) of both sexes and the remaining middle-aged mice were group (social) housed, but not exposed to enriching objects. After the enrichment period, all mice were tested in a 1-day version of the Morris water maze, in which both spatial and nonspatial memory were assessed. Immediately after testing, the hippocampus and frontoparietal cortex were dissected, and GAD activity and synaptophysin levels were measured. Environmental enrichment reduced the age-related impairment in spatial acquisition and retention; relative to adult social controls, middle-aged enriched mice were unimpaired, whereas middle-aged social controls were impaired. This reduction was similar in middle-aged males and females. Enrichment did not affect cued memory in either sex. Although hippocampal GAD activity was increased by enrichment in males, all other neurochemical measurements were unaffected by enrichment or aging in either sex. These data suggest that environmental enrichment initiated at middle age can reduce age-related impairments in spatial memory in males and females, although the underlying neurobiological mechanisms of this effect remain unknown. 相似文献
987.
Emotional risk factors were examined in 129 litigant and nonlitigant patients diagnosed with Postconcussional Disorder (PCD) following Mild Traumatic Brain Injury (MTBI). According to Millon Clinical Multiaxial Inventory (MCMI) criteria, four subgroups emerged: (a) 14.7% met criteria for an Axis I disorder, (b) 24.8% for an Axis II disorder, (c) 24.0% for bout Axis I and II disorders, and (d) 36.4% fell below threshold for psychopathology. Thus, 63.5% endorsed emotional pathology. Of the four groups, those with both Axis I and II psychopathology presented the greatest number of emotional complaints in a clinical interview and manifested the lowest neurocognitive test scores. Motor skills, verbal abilities, memory functioning, and IQ were primarily affected. With the exception of post-morbid emotional complaints, no significant differences were identified between litigants and nonlitigants. Our analysis suggests that the combination of both Axis I and II psychopathology is associated with greater impairment following MTBI. 相似文献
988.
989.
990.
Generalized eta and omega squared statistics: measures of effect size for some common research designs 总被引:1,自引:0,他引:1
The editorial policies of several prominent educational and psychological journals require that researchers report some measure of effect size along with tests for statistical significance. In analysis of variance contexts, this requirement might be met by using eta squared or omega squared statistics. Current procedures for computing these measures of effect often do not consider the effect that design features of the study have on the size of these statistics. Because research-design features can have a large effect on the estimated proportion of explained variance, the use of partial eta or omega squared can be misleading. The present article provides formulas for computing generalized eta and omega squared statistics, which provide estimates of effect size that are comparable across a variety of research designs. 相似文献