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111.
An on-line assessment of causal reasoning during comprehension   总被引:3,自引:0,他引:3  
Fletcher and Bloom (1988) have argued that as readers read narratives, clause by clause, they repeatedly focus their attention on the last preceding clause that contains antecedents but no consequences in the text. This strategy allows them to discover a causal path linking the text's opening to its final outcome while minimizing the number of times long-term memory must be searched for missing antecedents or consequences. In order to test this hypothesis, we examined the reading times of 25 subjects for each clause of eight simple narrative texts. The results show that: (1) causal links between clauses that co-occur in short-term memory (as predicted by the strategy) increase the time required to read the second clause; (2) potential causal links between clauses that never co-occur in short-term memory (again as predicted by the strategy) have no effect on reading time; and (3) reinstatement searches are initiated at the end of sentences that are causally unrelated to the contents of short-term memory or that contain clauses that satisfy goals no longer in short-term memory. These results support the claim that subjects engage in a form of causal reasoning when they read simple narrative texts.  相似文献   
112.
An investigation was made into the extent and time course of anticipatory coarticulation in the speech of two normal and two anterior aphasic, German-speaking subjects. Both labial and velar coarticulation gestures were investigated. Subjects produced sentences containing target words contrasting in postconsonantal vowel rounding (e.g., [geli:ge]/[gely:gel]) and in nasality (e.g., [ti:de]/[ti:ne]). Speech kinematics were monitored by means of electromagnetic articulography. The data revealed that for correct productions, aphasic speakers' coarticulatory patterns were more highly variable than those of control subjects. These differences, however, were found chiefly for spatial displacement characteristics, while the temporal aspects of articulator movement necessary for anticipatory coarticulation appeared largely intact. Articulator mistiming did not appear to explain a small corpus of stop/nasal substitution errors produced by one of the aphasic speakers.  相似文献   
113.
The cellular expression of S-100β protein is upregulated in Alzheimer's disease and in Down's syndrome, and this protein has been implicated in memory-related processes in laboratory animals. However, the possibility that the α subunit of S-100 is also involved in memory has not yet been examined. In the present study, day-old black Australorp white Leghorn cockerel chicks (Gallus domesticus) received injections of monoclonal antisera to S-100α (1:50) or S-100β (1:500) into each hemisphere immediately after training on a one-trial passive avoidance task. The chicks displayed significantly lower retention levels than control birds that had been injected with antisera to carbonic anhydrase, or with saline (p< .01). S-100α antisera had an amnestic effect when injected between 0 and 20 min after training, with memory deficits occurring from 30 min postlearning, at the point of transition between the A and the B phases of the Gibbs-Ng intermediate memory stage. By contrast, the S-100β antisera needed to be injected either 5 min before or immediately after training and produced amnesia 10 min earlier, at the start of the A phase of the intermediate memory stage. We conclude that the two subunits of the S-100 protein are required at different points in the sequence of events leading to the consolidation of passive avoidance memory.  相似文献   
114.
This study evaluates the behavioral consequences of childhood abuse (sexual, physical, or both), with particular focus on prevalence of posttraumatic stress disorder (PTSD). Three abuse type groups and nonabused controls were contrasted on behavioral rating scales and on structured psychiatric interview data. The participants (109 abused children and 16 normal control children) were recruited from Arkansas Children’s Hospital and local agencies for abused children. As expected, proportionately more females than males were sexually abused. Overall, males were rated as more disturbed than females. Type of abuse did not consistently influence behavioral ratings. Externalizing scores were significantly higher than internalizing scores in all abused groups. PTSD was diagnosed in 50% of the abused children, with a higher rate for boys who had been sexually abused as opposed to physically abused only (58% versus 13%). The most frequent comorbid condition with PTSD was Separation Anxiety. Sexually abused boys were hospitalized for psychiatric treatment at a higher rate than were other abused children.  相似文献   
115.
In a restricted class of item response theory (IRT) models for polytomous items the unweighted total score has monotone likelihood ratio (MLR) in the latent trait. MLR implies two stochastic ordering (SO) properties, denoted SOM and SOL, which are both weaker than MLR, but very useful for measurement with IRT models. Therefore, these SO properties are investigated for a broader class of IRT models for which the MLR property does not hold.In this study, first a taxonomy is given for nonparametric and parametric models for polytomous items based on the hierarchical relationship between the models. Next, it is investigated which models have the MLR property and which have the SO properties. It is shown that all models in the taxonomy possess the SOM property. However, counterexamples illustrate that many models do not, in general, possess the even more useful SOL property.Hemker's research was supported by the Netherlands Research Council, Grant 575-67-034. Junker's research was supported in part by the National Institutes of Health, Grant CA54852, and by the National Science Foundation, Grant DMS-94.04438.  相似文献   
116.
Anscombe On 'I'     
I examine the main arguments of Elizabeth Anscombe's difficult but fecund paper 'The First Person'. Anscombe argues that the first-person singular is not a device of reference, and, in particular, that it is not a device of indexical reference. Both arguments fail, but in ways that we can learn from.  相似文献   
117.
To determine the relative effectiveness of telephone intervention styles with suicidal callers, researchers listened unobtrusively to 617 calls by suicidal persons at two suicide prevention centers and categorized all 66,953 responses by the 110 volunteer helpers according to a reliable 20-category checklist. Outcome measures showed observer evaluations of decreased depressive mood from the beginning to the end in 14% of calls, decreased suicidal urgency ratings from the beginning to the end in 27% of calls, and reaching a contract in 68% of calls, of which 54% of contracts were upheld according to follow-up data. Within the context of relatively directive interventions, a greater proportion of Rogerian nondirective responses was related to significantly more decreases in depression. Reduction in urgency and reaching a contract were related to greater use of Rogerian response categories only with nonchronic callers.  相似文献   
118.
Two studies of college undergraduates (ns = 95 and 92, primarily non-Hispanic whites and Asian Americans) investigated gender stereotypes of stress and emotion, as well as variables that influence the perception of gender-related differences. Study 1 assessed how gender stereotypes differ from the self-reports of men and women. When asked to choose a label for the subjective experience of the average man and the average woman in a series of problematic hypothetical situations, participants generally tended to believe that the average female would feel ‘emotional,” but that the average male would feel “stressed.” By contrast, the label participants chose to describe their own subjective experience was not significantly affected by their gender. In addition, participants believed the average woman and man differed more in the intensity of their emotions than in the intensity of their stress, a belief contradicted by their own self-reports. Results of Study 2 indicated that gender-related differences in estimations of stress and emotion for the self were reduced or eliminated when specific information about experience-eliciting situations was provided. We would like to thank Matthew Dank for his help in preparing the stimulus materials.  相似文献   
119.
The misperception of alignment which is found in many geometric illusions can be quantified using relatively simple stimulus configurations. Perceived collinearity of one segment (designated as the test segment) is biased by a second segment (designated as the induction segment), with the size of effect being a function of the relative angle between the two segments. The process can be described as angular induction. The strength of bias is greatest when the induction segment is centered at the tip of the test segment. Tong and Weintraub have reported that lateral displacement from the tip, i.e., at right angles to the axis of the induction segment, produces a sharp drop in the strength of effect. This decline is described as a decay gradient for the angular induction. One experiment replicates and provides better quantification of this decay gradient. Two other experiments examine the decay gradient using a pair of induction segments, one on each side of the tip of the test segment. Displacement of the segments (either in the same direction or in opposite directions) produces substantially the same gradient of effect. Therefore, previous evidence of tandem boosting of effect for segment pairs does not depend on collinearity among the stimulus components. Finally, a fourth experiment finds that an induction segment which is at a fixed position and orientation differentially affects the influence of a variable induction segment. At some angles the influence of the variable segment is augmented, and at others it is suppressed. These findings are discussed in a neuroreductionist context, and a simple model for angular induction is presented.  相似文献   
120.
ASSOCIATIVE PROCESSES IN FALSE RECALL AND FALSE RECOGNITION   总被引:4,自引:0,他引:4  
Abstract— Studying a list of words associated to a critical nonpresented word results in high rates of false recall and false recognition for that nonpresented item (Roediger & McDermott, 1995) Two experiments examined the effect of manipulating the number of associates presented on false recall and later false recognition of a nonpresented item. In Experiment 1, associate lists of varying lengths were studied, in Experiment 2, list length was held constant and the number of associates within the list was manipulated. In both experiments, the rate of critical intrusions in recall increased steadily with increasing number of associates studied Most notably, the filler words used in Experiment 2 to equate the list lengths did not affect the rate of critical intrusions, although they did depress recall of studied words. False recall and false recognition appear to be tied to the total, not the mean, associative strength of items in the list.  相似文献   
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