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911.
A series of experiments investigated the integration of new vocabulary words into semantic memory and the creation of new associations between preexisting, but previously unrelated, words. The ability of the newly learned vocabulary words and associations to facilitate lexical decisions when serving as primes under conditions associated with automatic processing was used to index integration. The results indicate that very extensive study is necessary for such integration to occur and that it is easier to add a new word to semantic memory than to establish a link between two formerly unconnected words already in semantic memory. The implications of these results for models of semantic memory and the episodic/semantic distinction are considered.  相似文献   
912.
Summary In the literature two different views on the time course of activation of recognition units — hypothetical units that represent identity information — are proposed. The first view assumes that the recognition units accumulate activation gradually over time. The second assumes that the activation levels increase fast initially and then start to decrease. Hagenzieker and Van der Heijden (1990) have proposed a more general information-processing model, which is compatible with both views. In this model a treshold determines what type of time course will be obtained. For below-threshold-activation values a gradual accumulation of activation will be found; for above-threshold values activation levels will first increase and then, because of inhibition, decrease. This model served as a starting-point for the present paper. Elaboration of this model led to two testable hypotheses with regard to identification performance. The first prediction is that evidence for inhibition should be observed only under relatively bright luminance conditions. The second is that, given inhibition, the amount of the effect of this inhibition should increase over time. A partial-report bar-probe task was used to test the predictions. The experiment involved two luminance conditions and the information was sampled at two different moments in time. To control for possible localization artefacts a digit-naming task was also used. Evidence for inhibition was found in both luminance conditions. In accordance with the model the amount of the effect of inhibition increased over time.  相似文献   
913.
Two experiments were performed to assess the accuracy and precision with which adults perceive absolute egocentric distances to visible targets and coordinate their actions with them when walking without vision. In experiment 1 subjects stood in a large open field and attempted to judge the midpoint of self-to-target distances of between 4 and 24 m. In experiment 2 both highly practiced and unpracticed subjects stood in the same open field, viewed the same targets, and attempted to walk to them without vision or other environmental feedback under three conditions designed to assess the effects on accuracy of time-based memory decay and of walking at an unusually rapid pace. In experiment 1 the visual judgments were quite accurate and showed no systematic constant error. The small variable errors were linearly related to target distance. In experiment 2 the briskly paced walks were accurate, showing no systematic constant error, and the small, variable errors were a linear function of target distance and averaged about 8% of the target distance. Unlike Thomson's (1983) findings, there was not an abrupt increase in variable error at around 9 m, and no significant time-based effects were observed. The results demonstrate the accuracy of people's visual perception of absolute egocentric distances out to 24 m under open field conditions. The accuracy of people's walking without vision to previously seen targets shows that efferent and proprioceptive information about locomotion is closely calibrated to visually perceived distance. Sensitivity to the correlation of optical flow with efferent/proprioceptive information while walking with vision may provide the basis for this calibration when walking without vision.  相似文献   
914.
Saccadic reaction times of dyslexic and age-matched normal subjects   总被引:2,自引:0,他引:2  
B Fischer  H Weber 《Perception》1990,19(6):805-818
Saccadic reaction times (SRT) were measured in a simple task: subjects had to make saccades from a central fixation point to peripheral targets, which appeared randomly 4 deg to the left or to the right. In the first test the fixation point went off before the target appeared (gap trials); in the second test it remained on the screen (overlap trials). The distribution of SRTs for trained normal adults (N = 4), untrained normal adults (N = 11), untrained normal children (aged 9-11 years, N = 9), untrained normal teenagers (aged 15-17 years, N = 8), dyslexic children (aged 9-11 years, N = 15), and dyslexic teenagers (aged 15-17 years, N = 5) were compared, with special emphasis on the number of express saccades, ie saccades with extremely short reaction times (100-120 ms, under the present conditions). In normal adults with the gap paradigm, the distribution of reaction times typically exhibits two or three modes (express saccades, fast regular saccades, and very few slow regular saccades), whereas in the overlap paradigm only one or two modes (few fast regular saccades and many slow regular saccades) are obtained. On average, normal children produce more express saccades than naive normal adults. Dyslexic children produce more express saccades than the normal age-matched controls. Among the dyslexic children, four different types of abnormalities in their reaction times were encountered. The group of dyslexic teenagers was characterized by a larger number of express saccades at the expense of fast regular saccades in gap trials and by fewer express saccades and fewer fast regular saccades in overlap trials when compared to the age-matched control group. It is concluded that the abnormal patterns of saccadic reaction times reflect defects in the system of visual attention and/or in its control over the oculomotor system, rather than indicating a defect in the oculomotor system itself. In this context, symptoms of dyslexia appear as a combination of attentional deficits and irregular timing of saccadic eye movements.  相似文献   
915.
This study was designed to examine the correlates of developmental psychological stress for 36 middle-aged professional men. Based on sex role convergence and role adjustment theories, two sets of predictor variables were hierarchically entered into a multiple regression equation with a third set of variables entered to control for individual stressors. Controlling for individual stressors, midlife stress outcome was found to be influenced only by role adjustment (R2=.3593). The sex role convergence cluster did not account for a significant increase in variance. Controlling for individual stressors, the best univariate predictors of stress outcome associated with the midlife transition were (a) the quality of the parent-adolescent relationship and (b) marital satisfaction.  相似文献   
916.
Interdisciplinary training in behavioral sciences and the law should be appropriate for a criminal justice education program. However, adopting such an interdisciplinary goal is problematic because the divisions in the types of educational curricula need to be confronted. The relationships of the criminal justice academic community with the profession, and of the behavioral sciences with present criminal justice policies, must also be addressed in the attempt to develop familiarity with behavioral sciences and their legal relevance in shaping the criminal justice system. These factors may hinder extensive implementation of such training. Suggestions are made for incorporating this raining in a criminal justice curriculum.  相似文献   
917.
Feigned insanity in nineteenth-century America is appraised through a review of the medical and legal literature. The authors focus on the explanations for feigning, procedures used in uncovering feigning, and the role of feigning in the courtroom. This discussion of feigned insanity demonstrates the remarkable consistency of approach to this form of malingering over the past 200 years.  相似文献   
918.
Spouse abuse is examined from the perspective of attribution theory. Aggressors are seen as attributing their violent behavior to external causes, whether by projecting their negative traits onto their spouses or by finding excuses which blame temporary environmental factors. In contrast, victims often attribute the abuse to defects within themselves or situational factors affecting their spouses. The attribution process seems affected by the frequency, intensity and duration of the abuse, with temporal factors playing an important role in the woman's internalizing style. Furthermore, inadequate early coping efforts play a powerful role in establishing cognitive-perceptual patterns that serve to perpetuate the abuse.  相似文献   
919.
The purpose of this study was to investigate the structure of emotional responses to pictorial stimuli within the affective space defined by orthogonal dimensions of positive affect (PA) and negative affect (NA). College student participants (N = 151) viewed 60 color photographic slides from the International Affective Picture System (Lang, Bradley, & Cuthbert, 1995) and rated their emotional responses to each slide using the Positive and Negative Affect Schedule (Watson, Clark, & Tellegen, 1988). Consistent with prediction, affective reactions to pleasant slides were characterized as high in PA, and low in NA. Unpleasant slides produced elevations on the NA scale, but contrary to expectation, also produced elevated ratings of PA, with the magnitude of PA scale scores increasing systematically with NA scale scores. The results suggest an interesting divergence between the structure of pictorially elicited affective reactions and that of ad hoc mood states. Directions for future research are discussed in relation to the unique properties of the slide viewing paradigm.  相似文献   
920.
The face-to-face interactions of 43 polydrug-with-cocaine-using mothers and their infants at 3 and 6 months were compared to 17 non-cocaine-but other-drug-using mothers and 21 mothers who used no drugs during their pregnancy. Coders blind to mothers' drug use status scored 3 min of face-to-face interactions for 16 measures of maternal and infant interactive behaviors. A principal component of 7 behaviors formed a measure of maternal attentiveness; a principal component of 5 behaviors formed a measure of mother-infant dyadic organization; and a principal component of 4 behaviors formed a measure of infant readiness to interact. A measure of maternal interruption was computed as the mean standard score of 3 additional interruptive behaviors. At 3 and 6 months, polydrug-with-cocaine-using mothers were less attentive to interactions, and polydrug-with-cocaine-using mothers and their infants engaged in fewer dyadic interactions than either non-cocaine or non-drug-using mothers. Compared to 3 months, polydrug-with-cocaine-using mothers at 6 months were less attentive to interactions and more frequently interrupted interactions by looking away, redirecting the infant, or withdrawing, whereas non-cocaine-using and non-drug- using mothers showed no change or an improvement in attentiveness to interactions and a decrease in interruptions. No differences emerged in the interactive behaviors of the infants of polydrug- with-cocaine-using, non-cocaine-using, or non-drug-using mothers. Cocaine use represents a significant risk for diminished parental attentiveness and responsiveness to infants and for diminished interactiveness in infants.  相似文献   
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