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251.
This study investigated whether parent-adolescent disagreement regarding adolescents' behavioral and emotional problems predicted adverse outcome. A Dutch sample of 15- to 18-year-olds was prospectively followed across a 4-year interval. The Child Behavior Checklist (CBCL: T. M. Achenbach, 1997) and Youth Self-Report (YSR; T. M. Achenbach, 1991b) were administered at initial assessment, and the following signs of poor outcome were assessed 4 years later: police/judicial contacts, expulsion from school/job, suicidal ideation, unwanted pregnancy, suicide attempts, deliberate self-harm, referral to mental health services, report of having a behavioral or emotional problem, and feeling the need for professional help without actually receiving help. Twenty CBCL syndrome scores, 23 YSR syndrome scores, and 16 discrepancy scores were significant predictors of poor outcome. It was concluded that to determine the prognosis of psychopathology in adolescents, discrepancies between informants may be important.  相似文献   
252.
The model of anterior asymmetry and emotion proposes an asymmetric representation of approach and withdrawal systems in the left and right anterior brain regions. Within this framework, 3 different concepts have been related to anterior asymmetry: affective valence, motivational direction, and behavioral activation. The aim of the present study was an empirical investigation into the relation between anterior cortical activity and questionnaire measures related to the 3 dimensions positive versus negative affect, approach versus withdrawal motivation, and behavioral activation versus inhibition. Subjects with relative greater left than right frontal cortical activity showed higher anger-out scores and lower anger-control scores. These results support the hypothesis that motivational direction is related to frontal asymmetry (approach-left and withdrawal-right). Furthermore, subjects with greater bilateral (left and right) frontal cortical activity showed higher behavioral activation scores. This finding might suggest that behavioral activation is related to approach and withdrawal motivation.  相似文献   
253.
Insights from appraisal theories of emotion are used to integrate elements of theories on collective action. Three experiments with disadvantaged groups systematically manipulated procedural fairness (Study 1), emotional social support (Study 2), and instrumental social support (Study 3) to examine their effects on collective action tendencies through group-based anger and group efficacy. Results of structural equation modeling showed that procedural fairness and emotional social support affected the group-based anger pathway (reflecting emotion-focused coping), whereas instrumental social support affected the group efficacy pathway (reflecting problem-focused coping), constituting 2 distinct pathways to collective action tendencies. Analyses of the means suggest that collective action tendencies become stronger the more fellow group members "put their money where their mouth is." The authors discuss how their dual pathway model integrates and extends elements of current approaches to collective action.  相似文献   
254.
In most individuals, food intake occurs as discrete bouts or meals, and little attention has been paid to the factors that normally determine when meals will occur when food is freely available. On the basis of experiments using rats, the authors suggest that when there are no constraints on obtaining food and few competing activities, 3 levels of interacting controls normally dictate when meals will start. The first is the genetically determined circadian activity pattern on which nocturnal animals tend to initiate most meals in the dark. The second is the regularly occurring changing of the light cycle: These changes provide temporal anchors. The third relates to the size of the preceding meal, such that larger meals cause a longer delay until the onset of the next meal. Superimposed on these 3 are factors related to learning, convenience, and opportunity.  相似文献   
255.
Verb production is notoriously difficult for individuals with Broca's aphasia, both at the word and at the sentence level. An intriguing question is at which level in the speech production these problems arise. The aim of the present study is to identify the functional locus of the impairment that results in verb production deficits in Broca's aphasia. Levelt's (1989) model is used as a theoretical framework for this study. Two experiments have been conducted, one on verb movement and one on verbs with alternating transitivity. The results suggest that the functional impairment in Broca's aphasia should be located in Levelt's "grammatical encoder."  相似文献   
256.
Freyd and Tversky's [Am. J. Psychol. 97 (1984) 109] data suggested that human observers tend to overestimate relatively high levels of symmetry (symmetry effect), and tend to underestimate relatively low levels of symmetry (asymmetry effect). However, on the basis of their holographic approach to visual regularity, van der Helm and Leeuwenberg [Psychol. Rev. 103(3) (1996) 429] predicted that, at any level of symmetry, both symmetry and asymmetry effects may occur as a consequence of correct estimates of symmetry-to-noise ratios. This prediction was tested in two experiments, with tasks and stimuli similar to those in Freyd and Tversky's study. First, subjects had to judge whether a noisy symmetry is more similar to a slightly more symmetrical variant or to a slightly less symmetrical variant. Second, for every pair of stimuli in such a triadic comparison, subjects had to judge which stimulus is the more symmetrical one. The results from both experiments show that the occurrence of (a)symmetry effects indeed depends on symmetry-to-noise ratios.  相似文献   
257.
It is often intuitively assumed that disconnected image fragments result in a representation of separate objects. When objects are partly occluded, disconnected image fragments can still result in a representation of a single object, based on visual completion. In a simultaneous matching task, displays showing one object, partly occluded objects, or two objects were compared with each other. When only a translation was required to match pairs of displays, one-object displays were matched faster than both occluded-object and two-object displays, which did not differ significantly from each other. When mental rotation and translation were required, the one-object displays were again matched the fastest. In addition, an advantage for occluded-object displays compared with two-object displays was found. We conclude that when the generation of a mental representation is likely, object-based connectedness determines object matching. Mental rotation then seems to depend on the number of objects rather than on the number of image fragments.  相似文献   
258.
Grammatical-specific language impairment (G-SLI) in children, arguably, provides evidence for the existence of a specialised grammatical sub-system in the brain, necessary for normal language development. Some researchers challenge this, claiming that domain-general, low-level auditory deficits, particular to rapid processing, cause phonological deficits and thereby SLI. We investigate this possibility by testing the auditory discrimination abilities of G-SLI children for speech and non-speech sounds, at varying presentation rates, and controlling for the effects of age and language on performance. For non-speech formant transitions, 69% of the G-SLI children showed normal auditory processing, whereas for the same acoustic information in speech, only 31% did so. For rapidly presented tones, 46% of the G-SLI children performed normally. Auditory performance with speech and non-speech sounds differentiated the G-SLI children from their age-matched controls, whereas speed of processing did not. The G-SLI children evinced no relationship between their auditory and phonological/grammatical abilities. We found no consistent evidence that a deficit in processing rapid acoustic information causes or maintains G-SLI. The findings, from at least those G-SLI children who do not exhibit any auditory deficits, provide further evidence supporting the existence of a primary domain-specific deficit underlying G-SLI.  相似文献   
259.
In several recent studies, saccadic eye movements were found to be influenced by concurrent reaching movements. The authors investigated whether that influence originates in limb kinematic or kinetic signals. To dissociate those 2 possibilities, the authors required participants (N = 6) to generate pointing movements with a mass that either resisted or assisted limb motion. With practice, participants were able to generate pointing responses with very similar kinematics but whose kinetics varied in a systematic manner. The results showed that saccadic output was altered by the amount of force required to move the arm, consistent with an influence from limb kinetic signals. Because the interaction occurred before the pointing response began, the authors conclude that a predictive signal related to limb kinetics modulates saccadic output during tasks requiring eye-hand coordination.  相似文献   
260.
Investigators often use mass perturbation of body segments as an experimental paradigm to study movement coordination. To analyze the effect of mass perturbation on small-amplitude oscillations, the authors linearize the equation of motion of a single segment moving in a vertical plane and derive the effect of added mass on the undamped eigenfrequency, the relative damping, and the low-frequency control gain of the segment. Mass addition results in a decrease in both the relative damping and the low-frequency control gain; the undamped eigenfrequency increases for mass addition between the pivot point and R0 (where R0 is the length of a point mass pendulum whose undamped eigenfrequency is identical to that of the unperturbed segment), decreases for mass addition beyond R0, and remains unaffected for mass addition at R0. For a typical lower leg + foot segment, R0 is just proximal to the ankle joint. That location may explain the absence of an effect on oscillation frequency in studies in which mass has been added to the ankle. The authors' analysis provides a basis for a more effective application of mass perturbations in future experiments.  相似文献   
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