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151.
Factors determining why acts are regarded as aggressive were investigated in a sample of 303 subjects (140 males, 163 females, M age = 17.7 yr., SD = 1.4). A model was tested, according to which people base their attribution of aggression to acts on four factors: (1) intention (yes/no), (2) reason (attack/defense), (3) injury (death/injury/no injury), and (4) mode (weapon/bare hands/nonphysical means). All four factors contributed to the explanation of attribution of aggression, and the order of importance was the one mentioned above, intention being most important. The interaction between intention and reason was the second most important, contributing more than reason alone. The findings are consistent with the severity of punishment in sentences for different crimes of violence.  相似文献   
152.
We examined the differential impact of chronic versus acute economic stress on depressive mood among a sample of 1241 low-income, single, European and African American women. Based on Hobfoll's (1988, 1989) conservation of resources (COR) theory, we predicted that acute resource loss would be more distressing than chronic economic lack. That is, although chronically impoverished conditions are stressful, the attendant resource losses created will be more distressing. We further predicted that mastery and social support would be more beneficial in offsetting the negative consequences of acute resource loss than the negative consequences of chronic economic lack, because acute loss creates identifiable demands that resources may address. Hence, we hypothesized that mastery and social support would show stress buffering effects only for material loss, not chronic lack. The findings generally supported the hypotheses, but mastery buffered only European American women's resource loss and social support buffered only African American women's resource loss. The findings are discussed in light of implications for prevention within theoretical and cultural contexts.  相似文献   
153.
Although the vagus nerve has traditionally been considered to perform efferent functions, in reality it performs significant afferent functions as well, carrying information from the body, head, and neck to the brain. Preliminary studies examining this afferent activity led to the theory that vagus nerve stimulation (VNS) could successfully control seizure activity in persons who are refractory to antiepileptic medications. Unlike other forms of brain stimulation, VNS is unable to directly stimulate multiple discrete areas of the brain; however, through several pathways, it is able to relay sensory information to higher brain regions. An implantable VNS device known as the VNSTM NeuroCybernetic Prosthesis (NCP) System has been used in approximately 9,000 epilepsy patients in Europe and the United States since 1994. The implant has reduced seizure frequency by an average of 25% to 30%, with minimal side effects. Studies underway are also showing some degree of success in the management of treatment-refractory depression. The future efficacy of the implantable system in other disorders may depend on whether the implant can be more precisely focused to affect different brain regions. Research in this area is underway.  相似文献   
154.
155.
Event-related brain potentials (ERPs) of 21 subjects were recorded in a choice reaction time task with a repeating eight-element long stimulus sequence. The regular event sequence was sometimes interrupted by 'perceptual' or by 'motor deviants' which both replaced an expected stimulus but either preserved or violated the sequence of motor responses. Response times confirmed that all subjects had acquired some knowledge of the sequential dependencies. By means of a post-experimental free recall and recognition test, subjects were classified as having either explicit or implicit knowledge of the event sequence. The ERPs showed different effects for different types of stimuli and the two groups. In the group of explicit learners, a larger N200 component was evoked by both types of deviants and a larger P300 by motor deviants only. In the group of implicit learners these 'perceptual components' remained unaffected. In contrast, in both groups of subjects the lateralized readiness potential (LRP) which accompanied motor deviants revealed a partial activation of the to be expected but incorrect response, i.e. motor learning. These results suggest that explicit learners acquire knowledge about both, stimulus and response dependencies while implicit learners acquire knowledge about response dependencies only.  相似文献   
156.
Response time (RT) distributions from three fixed foreperiod conditions (2, 4, and 8 s) in a warned four-choice RT task were obtained for a group of boys with attention-deficit/hyperactivity disorder, combined type (ADHD; n = 17) and for two groups of normal control boys (age-matched, n = 18, and younger-aged, n = 10). Quantitative measures of distributional shape were derived by fitting the ex-Gaussian distributional model to the individual RT data. Statistical results indicate that the ADHD distributions differ from the age-matched control distributions with respect to the size of the tail (larger for the ADHD boys), but differ from the younger control distributions with respect to the location of the leading edge (slower for the younger control boys). Receiver operating characteristic (ROC) results reveal that the ex-Gaussian exponential component is highly diagnostic of the ADHD boys.  相似文献   
157.
This study assessed family perception patterns of interpersonal behavior in families with a daughter diagnosed with an eating disorder 6 years after treatment that used a prospective design. Family perception patterns of patients found to have a poor outcome at followup (n = 15) were compared with patients with a good outcome (n = 23), as well as a control group (n = 36). Using the system of multiple level observation of groups (SYMLOG), all 238 family members evaluated themselves and each other. The index patients with a poor outcome perceived themselves as friendlier and more positive than they were perceived by their families. In comparison to parents of daughters with a good outcome and the control group, parents of daughters in the poor outcome group perceived themselves to be less friendly than their partners perceived them to be. A rigid polarization of the perception of the index patient by family members and a discrepancy in this perception between the index patient and the rest of the family were found to be indicative of a poor prognosis. Implications for treatment based on family perception patterns of interpersonal behavior are discussed.  相似文献   
158.
The processing of transparent Finnish compound words was investigated in 2 experiments in which eye movements were recorded while sentences were read silently. The frequency of the second constituent had a large influence (95 ms) on gaze duration on the target words, but its influence was relatively late in processing: A clear effect only occurred on the probability of a third fixation. The frequency of the whole compound word had a similar influence on gaze duration (82 ms) and influenced eye movements at least as rapidly as did the frequency of the second constituent. These results, together with an earlier finding that the frequency of the first constituent affected the first fixation duration, indicate that the identification of these compound words involves parallel processing of both morphological constituents and whole-word representations.  相似文献   
159.
Participants lifted pairs of successively presented weights and compared them for heaviness, using the constant method with 2, 3, or 6 judgment categories. The standard weight (St) was 100, 200, or 300 g, either roving or fixed within a block. For each St, there were 5 comparison (Co) weights. The lifting orders were St-Co and, with 6 categories, Co-St. Time-order errors were negatively related to St magnitude, particularly with roving St. In terms of Hellstr?m's sensation-weighting theory, this result was accounted for by a smaller weighting coefficient for the first-presented stimulus than for the second. Time-order errors were negative on average, which was explained as the result of this weighting in conjunction with a low position of the reference level because of light background heaviness. With roving St, the dispersion of the subjective intrapair difference increased with St magnitude, providing evidence for Ekman's law (G. Ekman, 1956, 1959).  相似文献   
160.
Electroencephalograms were recorded in 22 men while solving tasks of visual-pattern completion and during mental relaxation. They were primed (by foregoing trials) to solve these tasks either in a predicative or functional mode of thinking. Predicative thinking required that in order to complete the pattern the subject had to get involved with the logic of the static structure of the pattern and therefore had to recognize the recurrence of certain features of the elements (e.g., shape, color, and size). Functional thinking required involvement in a dynamic reading of the logic of the pattern and therefore to search for operations and actions to be performed on the pattern elements (e.g., pushing, mirroring, and rotating). The EEG complexity during predicative thinking decreased in comparison to functional thinking and mental relaxation, with this reduction being most pronounced over the right parietal cortex. A reduction in dimensional complexity during functional thinking as compared to mental relaxation, which was concentrated over the left central cortex, although significant, was less clear. The reduced EEG complexity during predicative thought, dominant over the right hemisphere, could reflect increased competitive inhibition among respective cortical neuron assemblies in association with the visual analysis of static element features, converging upon those predicates relevant for the solution.  相似文献   
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