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681.
This research investigated goal setting on engineering teams with geographically dispersed members. A survey was designed to measure the Quality of Goal Setting, Goal Commitment, Perceived Task Outcomes, and Perceived Psychosocial Outcomes, all constructs and scales used in previous research on project teams. 82 respondents from 12 virtual teams participated. Analysis suggested the quality of goal setting affected Perceived Task Outcome (t = 2.40, p < .05) but not Perceived Psychosocial Outcomes. Further regression analysis indicated goal commitment predicted significant variance in both Perceived Task Outcomes (t = 2.35, p < .05) and Perceived Psychosocial Outcomes (t = 4.3, p < .01). These results suggest that setting high quality goals and building commitment to goals significantly affect perceptions of outcomes on virtual project teams.  相似文献   
682.
Eighteen examiners, well trained in the Comprehensive System (CS; Exner, 2003), administered the Rorschach to 357 Portuguese children, in the first through fifth grades, attending schools located in Lisbon and the surrounding neighborhood. Coding was done by 5 of the examiners, each one having more than 5 years of experience with the CS. For this study, coding was reviewed by the authors. Five records were randomly selected from each age group to assess intercoder reliability. Janson and Olsson's (2004) iota was used to assess reliability of the main variable categories. Results are high, with iota ranging from 0.87 to 0.98 across the coding categories. CS variables are presented and key data were chosen and reviewed. A discussion of some data and their comparison with corresponding American data are made, permitting some interesting developmental and cross-cultural questions to be addressed.  相似文献   
683.
The bilateral intranigral infusion of 1 micromol 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in adult male Wistar rats caused a specific and partial loss of substantia nigra pars compacta (SNc) dopamine neurons, a partial depletion of striatal dopamine, and a deficit to learn the intra-maze cued version of the Morris water maze. Pre-training the SNc rats in the spatial version of the water maze or simply maintaining the animals on the water maze platform reversed this deficit. This improvement was even observed when the order of the extra-maze cues presented to the rats during pre-training of the spatial version was changed during training of the intra-maze cued version. However, this deficit was not reversed either by maintaining the animals on the platform if the spatial cues were surrounded and covered with a curtain or by swimming sessions in the maze without the escape platform and the curtain. These findings suggest that none of the following elements alone, learned during the spatial task pre-training, could help SNc rats learn the intra-maze cued task: improvement of swimming skills or knowledge of the existence of the escape platform; distance between the platform and the border of the pool; location of a particular extra-maze cue; relations among extra-maze cues. However, the simultaneous presence of the escape platform and extra-maze cues (irrespective of their relational configuration) during the pre-training sessions proved to be necessary for this improving effect to occur.  相似文献   
684.
Environmental enrichment (EE) results in improved learning and spatial memory, as well as attenuates morphological changes resulting from cerebral ischemia in adult animals. This study examined the effects of daily EE on memory deficits in the water maze and cerebral damage, assessed in the hippocampus and cerebral cortex, caused by neonatal hypoxia-ischemia. Male Wistar rats in the 7th postnatal day were submitted to the Levine-Rice model of neonatal hypoxia-ischemia (HI), comprising permanent occlusion of the right common carotid artery and a period of hypoxia (90 min, 8%O(2)-92%N(2)). Starting two weeks after the HI event, animals were stimulated by the enriched environment (1h/day for 9 weeks); subsequent to the stimulation, performance of animals in the water maze was assessed. HI resulted in spatial reference and working memory impairments that were completely reversed by EE. Following the behavioral study, animals were killed and the hippocampal volume and cortical area were estimated. There was a significant reduction of both hippocampal volume and cortical area, ipsilateral to arterial occlusion, in HI animals; environmental stimulation had no effect on these morphological measurements. Presented data indicate that stimulation by the daily environmental enrichment recovers spatial memory deficits caused by neonatal hypoxia-ischemia without affecting tissue atrophy in either hippocampus or cortex.  相似文献   
685.
Recent event-related potential studies report a P600 effect to incongruous verbs preceded by semantically associated inanimate noun-phrase (NP) arguments, e.g., "eat" in "At breakfast the eggs would eat...". This P600 effect may reflect the processing cost incurred when semantic-thematic relationships between critical verbs and their preceding NP argument(s) bias towards different interpretations to those dictated by their sentences' syntactic structures. We have termed such violations of alternative thematic roles, 'thematic role violations.' Semantic-thematic relationships are influenced both by semantic associations and by more basic semantic features, such as a noun's animacy. This study determined whether a P600 effect can be evoked by verbs whose thematic structures are violated by their preceding inanimate NP arguments, even in the absence of close semantic-associative relationships with these arguments or their preceding contexts. ERPs were measured to verbs under four conditions: (1) non-violated ("At breakfast the boys would eat..."); (2) preceded by introductory clauses and animate NPs that violated their pragmatic expectations but not their thematic structures ("At breakfast the boys would plant..."); (3) preceded by semantically related contexts but inanimate NPs that violated their thematic structures ("At breakfast the eggs would eat..."); (4) preceded by semantically unrelated contexts and inanimate NPs that also violated their thematic structures ("At breakfast the eggs would plant..."). Pragmatically non-thematic role violated verbs preceded by unrelated contexts and animate NPs evoked robust N400 effects and small P600 effects. Thematically violated verbs preceded by inanimate argument NPs evoked robust P600 effects but no N400 effects, regardless of whether these inanimate arguments or their preceding contexts were semantically related or unrelated to these verbs. These findings suggest that semantic-thematic relations, related to animacy constraints on verbs' arguments, are computed online and can immediately impact verb processing within active, English sentences.  相似文献   
686.
This study examined the internal consistency, diagnostic efficiency, and validity of selected scales of the Millon adolescent clinical inventory (MACI; Millon et al., Manual for the Millon Adolescent Clinical Inventory, National Computer Systems, Minneapolis, MN, 1993). 241 psychiatrically hospitalized adolescents were administered the MACI and a battery of established self-report measures and a multidisciplinary team independently assigned DSM-IV psychiatric diagnoses at the time of discharge. The internal consistency of MACI scales ranged from 0.71 to 0.93. Conditional probabilities (sensitivity, specificity, positive predictive power, and negative predictive power) were calculated for selected disorders using independently generated clinical diagnoses as the standard. The diagnostic efficiencies for the selected scales were variable, with adequate performance for predicting classes of diagnoses but not for specific diagnoses. The MACI showed good criterion validity for most disorders, with participants with a clinical diagnosis having a significantly higher corresponding MACI scale score than participants not assigned that diagnosis. Concurrent validity, tested by correlating MACI scale scores with those of relevant, validated measures, was generally good. The MACI appears to be a psychometrically sound self-report instrument and appears valuable as a screening instrument for many problems found in adolescent psychiatric inpatients.  相似文献   
687.
Ayton P  Fischer I 《Memory & cognition》2004,32(8):1369-1378
The representativeness heuristic has been invoked to explain two opposing expectations--that random sequences will exhibit positive recency (the hot hand fallacy) and that they will exhibit negative recency (the gambler's fallacy). We propose alternative accounts for these two expectations: (1) The hot hand fallacy arises from the experience of characteristic positive recency in serial fluctuations in human performance. (2) The gambler's fallacy results from the experience of characteristic negative recency in sequences of natural events, akin to sampling without replacement. Experiment 1 demonstrates negative recency in subjects' expectations for random binary outcomes from a roulette game, simultaneously with positive recency in expectations for another statistically identical sequence-the successes and failures of their predictions for the random outcomes. These findings fit our proposal but are problematic for the representativeness account. Experiment 2 demonstrates that sequence recency influences attributions that human performance or chance generated the sequence.  相似文献   
688.
Why are human observers particularly sensitive to human movement? Seven experiments examined the roles of visual experience and motor processes in human movement perception by comparing visual sensitivities to point-light displays of familiar, unusual, and impossible gaits across gait-speed and identity discrimination tasks. In both tasks, visual sensitivity to physically possible gaits was superior to visual sensitivity to physically impossible gaits, supporting perception-action coupling theories of human movement perception. Visual experience influenced walker-identity perception but not gait-speed discrimination. Thus, both motor experience and visual experience define visual sensitivity to human movement. An ecological perspective can be used to define the conditions necessary for experience-dependent sensitivity to human movement.  相似文献   
689.
Several lines of evidence indicate that gamma-aminobutyric acid (GABA) type A (GABA(A)) receptors regulate memory consolidation. Here we studied the effect on consolidation of the selective antagonist of GABA(A) receptors, bicuculline, given into several regions of the cortex at different times after one-trial step-down inhibitory avoidance (0.5 mA, 2-s footshock). Rats were bilaterally implanted with cannulae aimed at the CA1 region of the dorsal hippocampus, entorhinal cortex or posterior parietal cortex, three areas known to be involved in the memory consolidation of this task. At different times after training, bicuculline (0.5 microg/side) was infused into the above mentioned structures. Bicuculline increased memory retention when administered either immediately or 1.5h after training into CA1, and both immediately and 3h after training in the entorhinal or parietal cortex. Thus, in agreement with previous findings using other drugs, the response was biphasic in these latter structures. This suggests that GABAergic mechanisms normally downregulate, memory processing by inhibiting on-going activities necessary for consolidation at the times in which bicuculline was effective in each structure. Based on previous findings, in the hippocampus, such activity involves a number of receptors and signaling pathways in the first 1.5h after training. In the entorhinal and parietal cortex memory-related activities include the participation of protein kinase A and extracellularly regulated kinase (ERK) twice, right after training and then again 3h later.  相似文献   
690.
To be effective, criminal justice policies should affect the underlying social norms for which the policies were enacted. This study sought to determine whether public perceptions of criminal justice policies on domestic violence affected social norms. Two waves of data were collected via a telephone survey where a random probability sample of 973 residents was drawn from 4 communities. A structural equation model was tested and confirmed. Results provided strong support for the hypothesis that perceptions of criminal justice policies have direct effects on attitudes toward criminal justice response, and indirect effects on victim-blaming attitudes, both underlying social norms related to domestic violence. The enactment of criminal justice policies, therefore, may have an impact beyond victims and perpetrators and lead to a transformation of the community through the emergence of new social norms. Public awareness campaigns designed to disseminate criminal justice policies may be instrumental in provoking social change.  相似文献   
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