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231.
In this study, we investigated patients with focal neurodegenerative diseases to examine a formal linguistic distinction between classes of generalized quantifiers, like "some X" and "less than half of X." Our model of quantifier comprehension proposes that number knowledge is required to understand both first-order and higher-order quantifiers. The present results demonstrate that corticobasal degeneration (CBD) patients, who have number knowledge impairments but little evidence for a deficit understanding other aspects of language, are impaired in their comprehension of quantifiers relative to healthy seniors, Alzheimer's disease (AD) and frontotemporal dementia (FTD) patients [F(3,77)=4.98; p<.005]. Moreover, our model attempts to honor a distinction in complexity between classes of quantifiers such that working memory is required to comprehend higher-order quantifiers. Our results support this distinction by demonstrating that FTD and AD patients, who have working memory limitations, have greater difficulty understanding higher-order quantifiers relative to first-order quantifiers [F(1,77)=124.29; p<.001]. An important implication of these findings is that the meaning of generalized quantifiers appears to involve two dissociable components, number knowledge and working memory, which are supported by distinct brain regions.  相似文献   
232.
S. E. Clark, A. Hori, A. Putnam, and T. J. Martin (2000) showed that collaboration on a recognition memory task produced facilitation in recognition of targets but had inconsistent and sometimes negative effects regarding distractors. They accounted for these results within the framework of a dual-process, recall-plus-familiarity model but showed only weak evidence to support it. The present results of 3 experiments present stronger evidence for Clark et al.'s dual-process view and also show why such evidence is difficult to obtain.  相似文献   
233.
In the first three experiments, subjects felt solid geometrical forms and matched raised-line pictures to the objects. Performance was best in experiment 1 for top views, with shorter response latencies than for side views, front views, or 3-D views with foreshortening. In a second experiment with blind participants, matching accuracy was not significantly affected by prior visual experience, but speed advantages were found for top views, with 3-D views also yielding better matching accuracy than side views. There were no performance advantages for pictures of objects with a constant cross section in the vertical axis. The early-blind participants had lower performance for side and frontal views. The objects were rotated to oblique orientations in experiment 3. Early-blind subjects performed worse than the other subjects given object rotation. Visual experience with pictures of objects at many angles could facilitate identification at oblique orientations. In experiment 5 with blindfolded sighted subjects, tangible pictures were used as targets and as choices. The results yielded superior overall performance for 3-D views (mean, M = 74% correct) and much lower matching accuracy for top views as targets (M = 58% correct). Performance was highest when the target and matching viewpoint were identical, but 3-D views (M = 96% correct) were still far better than top views. The accuracy advantage of the top views also disappeared when more complex objects were tested in experiment 6. Alternative theoretical implications of the results are discussed.  相似文献   
234.
Following a pretest, 8 participants who were unfamiliar with algebraic and trigonometric functions received a brief presentation on the rectangular coordinate system. Next, they participated in a computer-interactive matching-to-sample procedure that trained formula-to-formula and formula-to-graph relations. Then, they were exposed to 40 novel formula-to-graph tests and 10 novel graph-to-formula tests. Seven of the 8 participants showed substantial improvement in identifying formula-to-graph relations; however, in the test of novel graph-to-formula relations, participants tended to select equations in their factored form. Next, we manipulated contextual cues in the form of rules regarding mathematical preferences. First, we informed participants that standard forms of equations were preferred over factored forms. In a subsequent test of 10 additional novel graph-to-formula relations, participants shifted their selections to favor equations in their standard form. This preference reversed during 10 more tests when financial reward was made contingent on correct identification of formulas in factored form. Formula preferences and transformation of novel mathematical and stimulus functions are discussed.  相似文献   
235.
The Classification of Violence Risk (COVR) is an interactive software program designed to estimate the risk that a person hospitalized for mental disorder will be violent to others. The software leads the evaluator through a chart review and a brief interview with the patient. At the end of this interview, the software generates a report that contains a statistically valid estimate of the patient's violence risk-ranging from a 1% to a 76% likelihood of violence-including the confidence interval for that estimate, and a list of the risk factors that the program took into account to produce the estimate. In this article, the development of the COVR software is described and several issues that arise in its administration are discussed.  相似文献   
236.
Fitts's law holds that movement time (MT) increases with longer distances. Here we report a violation of this law: When the target appears in a structured, linear display with placeholders indicating the possible target locations, MT to the most distant target is not longer than MT to the second most distant target, but rather tends to be shorter. Furthermore, the presence of placeholders attenuates the range effect that occurs in the absence of placeholders. These findings suggest that Fitts's law may be limited to egocentric visuomotor action, and that the visual control of hand movements may use allocentric, in addition to egocentric, spatial information.  相似文献   
237.
Younger and older African American and Caucasian American adults, who were matched by age (M age = 40.63 years), completed a survey on perceptions of aging and subjective age. The 2 groups did not differ in the age they considered someone to be old (M age = 74.5 years). However, when asked which age was the happiest age, African Americans chose a significantly younger age (M age = 18.26 years) than did Caucasian Americans (M age = 31.32 years), and this racial group difference interacted with age differences such that older Caucasian Americans named an older age than did younger Caucasian Americans. The authors found no such age difference for African Americans. When asked if old age was a happy time, 60% of Caucasian Americans answered yes, whereas only 2% of African Americans answered yes. These and other differences in images and concerns of old age and subjective age suggest a far more negative view of aging for African Americans and a need for changes in the provision of positive information about aging for this group.  相似文献   
238.
This study investigated the extent to which the link between perceived social support and affect reflected support recipients' trait perceived support as well as three distinct social processes: the objective supportiveness of providers, the unique relationships among recipients and providers that were stable over occasions, as well as the unique relationships that varied across occasions. Ten recipients interacted with each of the same four providers on five separate occasions, for a total of 200 interactions. Recipients and independent observers rated recipient affect and provider support. Greater perceived support was related to greater positive affect for recipients' trait perceived support, as well as for relationships that were stable over occasions and relationships that varied across occasions. No social support effects were found for negative affect. Perceived similarity was a consistent predictor of recipients' support perceptions. Implications for social support models and interventions were discussed.  相似文献   
239.
Recent reports have shown that saccades can deviate either toward or away from distractors. However, the specific conditions responsible for the change in initial saccade direction are not known. One possibility, examined here, is that the direction of curvature (toward or away from distractors) reflects preparatory tuning of the oculomotor system when the location of the target and distractor are known in advance. This was investigated by examining saccade trajectories under predictable and unpredictable target conditions. In Experiment 1, the targets and the distractors appeared unpredictably, whereas in Experiment 2 an arrow cue presented at fixation indicated the location of the forthcoming target prior to stimulus onset. Saccades were made to targets on the horizontal, vertical, and principal oblique axis, and distractors appeared simultaneously at an adjacent location (a separation of +/- 45 degrees of visual angle). On average, saccade trajectories curved toward distractors when target locations were unpredictable and curved away from distractors when target locations were known in advance. There was no overall difference in mean saccade latencies between the two experiments. The magnitude of the distractor modulation of saccade trajectory (either toward or away from) was comparable across the different saccade directions (horizontal, vertical, and oblique). These results are interpreted in terms of the time course of competitive interactions operating in the neural structures involved in the suppression of distractors and the selection of a saccade target. A relatively slow mechanism that inhibits movements to distractors produces curvature away from the distractor. This mechanism has more time to operate when target location is predictable, increasing the likelihood that the saccade trajectory will deviate away from the distractor.  相似文献   
240.
Previous research has shown that in a three-term spatial reasoning task, the second premise of a German premise pair is especially easy to comprehend if (1) the prepositional object rather than the grammatical subject denotes the given entity, and if (2) the term denoting the given entity precedes the term denoting the new entity. Accordingly, the second premise is easiest to comprehend with noncanonical word order--that is, with the prepositional object in preverbal position denoting the given entity (e.g., To the right of the given object is the new subject). This finding is explained in terms of contextual licensing of noncanonical word order. Here, we discuss and tested two alternative accounts of contextual licensing, given-new and partially ordered set relations (Poset). The given-new account claims that noncanonical word order is licensed by the term denoting the given entity preceding the term denoting the new entity. On the Poset account, noncanonical word order is licensed if the preverbal constituent introduces a new entity that stands in a transitive, irreflexive, and asymmetric relation to a given entity. Comprehension times for second premises with spatial adverbs in four different word orders support both accounts of contextual licensing; Poset licensing was stronger than given-new licensing.  相似文献   
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