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831.
832.
Prior experiments on shape constancy from novel views are inconclusive: Some show that shapes of objects can be recognized reliably from novel views, whereas others show just the opposite. Our analysis of prior results suggests that shape constancy from novel views is reliable when the object has properties that constrain its shape: The object has volumetric primitives, it has surfaces, it is symmetrical, it is composed of geons, its contours are planar, and its images provide useful topological information about its three-dimensional structure. To test the role of some of these constraints, we performed a set of experiments. Solid shapes (polyhedra) were shown on a computer monitor by means of kinetic depth effect. Experiment 1 showed that shape constancy can be reliably achieved when a polyhedron is represented by its contours (most of the constraints are present), but not when it is represented by vertices or by a polygonal line connecting the vertices in a random order (all the constraints are absent). Experiments 2 and 3 tested the role of individual constraints. Results of these experiments show that shape constancy from novel views is reliable when the object has planar contours and when the shapes of the contours together with topological information about the relations among the contours constrain the possible interpretations of the shape. Symmetry of the object and the topological stability of its image also contribute to shape constancy.  相似文献   
833.
We have abandoned the slave trade, and come to abhor it. Could the same happen with the arms trade? Even if we are not pacifists, and allow some use of force in self-defence, we must have serious ethical questions to ask about the trade in weaponry on which our economies are now so dependent. I distinguish the various forms these questions take for governments and individuals, and argue for some answers.  相似文献   
834.
Previous research has demonstrated that infants under 17 months have difficulty learning novel words in the laboratory when the words differ by only one consonant sound, irrespective of the magnitude of that difference. The current study explored whether 15‐month‐old infants can learn novel words that differ in only one vowel sound. The rich acoustic/phonetic properties of vowels allow for a detailed analysis of the contribution of acoustic/phonetic cues to infants’ performance with similar‐sounding words. Infants succeeded with the vowel pair /i/–/I/, but failed with vowel pairs /i/–/u/ and /I/–/u/. These results suggest that infants initially use the most salient acoustic cues for vowels and that this staged use of acoustic cues both predicts and explains why infants can learn some words that differ in only a single vowel.  相似文献   
835.
We report three experiments to test the possibilities reasoners think about when they understand a conditional of the form ‘A only if B’ compared to ‘if A then B’. The experiments examine conditionals in the indicative mood (e.g., A occurred only if B occurred) and counterfactuals in the subjunctive mood (A would have occurred only if B had occurred). The first experiment examines the conjunctions of events that reasoners judge to be consistent with conditionals, e.g., A and B, not-A and not-B. It shows that people think about one possibility to understand ‘if’ and two possibilities to understand ‘only if’; they think about two possibilities to understand counterfactual ‘if’ and ‘only if’. The second experiment shows that the possibilities people think about when they understand ‘only if’ are in a different temporal order (e.g., B and A) to the possibilities they think about for ‘if’ (A and B). The third experiment shows that people make different inferences from ‘only if’ and ‘if’ conditionals and counterfactuals. The implications of the results for theories of counterfactual conditionals are considered.  相似文献   
836.
Theory of Mind (ToM) and Executive Function (EF) have been associated with autism and with attention-deficit hyperactivity disorder (ADHD), and hence might play a role in similar syndromes found following profound early institutional deprivation. In order to examine this possibility the current study included a group of 165 Romanian adoptees, of whom 144 were adopted into the UK from deprived institutional settings before 43months of age, and a group of 52 within-UK adoptees, all adopted before 6months of age. Both groups were assessed at 6 and 11years. The Strange Stories task was used to assess ToM and the Stroop task was used to assess EF, both at age 11. The Romanian adoptees displayed deficits in both ToM and EF compared with the within-UK adoptee group. The degree of deficit was greater for children who had experienced more than 6months of institutional deprivation. Deficits in both domains (ToM and EF) were associated with each of the three apparently deprivation-specific problems, namely quasi-autism, disinhibited attachment and inattention/overactivity. Statistical analyses indicated a mediating role for both ToM and EF with respect to quasi-autism; possibly a partial mediating role for EF with respect to inattention/overactivity; and probably no mediating role for either ToM or EF in the case of disinhibited attachment. In conclusion, there is evidence for a possible mediating role for ToM and EF in the development of some apparently deprivation-specific difficulties in institution-reared Romanian adoptees, but neither accounts for the overall pattern of deprivation-related difficulties.  相似文献   
837.
This paper evaluated the quality of life (QOL) of people with multiple sclerosis (MS) and people from the general population. Gender differences between the 2 groups of respondents and the influence of coping style on adjustment were also evaluated. The participants were 381 (144 males, 237 females) people with MS, and 291 (101 males, 190 females) people from the general population. The results demonstrated that people with MS experienced lower levels of QOL than people from the general population for both the objective and subjective dimensions of all domains (physical health, psychological adjustment, social relationships, environmental adjustment). All coping strategies (problem-focused, focusing on the positive, detachment, wishful thinking, seeking social support) were important predictors of QOL for both males and females with MS, with wishful thinking being the strongest predictor of poor QOL. These results are discussed in terms of the various factors that impact on QOL among people with MS, and the types of coping strategies that are most adaptive in improving the QOL of people with this illness.  相似文献   
838.
The relationship between interest and knowledge was investigated in a representative sample of 11th grade students from cultures that differ in the strength of their gender-role stereotypes and their endorsement of effort-based versus interest-based learning. Among 11th graders from the United States (N = 1052), Taiwan (N = 1475), and Japan (N = 1119), boys preferred science, math, and sports, whereas girls preferred language arts, music, and art. General information scores were comparable across the three locations; however, boys consistently outscored girls. Gender and interest in science independently predicted general information scores, whereas gender and interest in math independently predicted mathematics scores. Cultural variations in the strength of the relationship between gender, interest, and scores indicate that specific socialization practices can minimize or exaggerate these gender differences.  相似文献   
839.
The present study was designed to assess children's memory and suggestibility in the context of ongoing child maltreatment investigations. One hundred eighty-nine 3-17-year-olds involved in evaluations of alleged maltreatment were interviewed with specific and misleading questions about an anogenital examination and clinical assessment. For the anogenital examination, children's stress arousal was indexed both behaviorally and physiologically. For all children, individual-difference data were gathered on intellectual and short-term memory abilities, general psychopathology, and dissociative tendencies. Interviewers' ratings were available for a subset of children concerning the amount of detail provided in abuse disclosures. Results indicated that general psychopathology, short-term memory, and intellectual ability predicted facets of children's memory performance. Older compared to younger children evinced fewer memory errors and greater suggestibility resistance. Age was also significantly related to the amount of detail in children's abuse disclosures. Neither dissociation nor stress arousal significantly predicted children's memory. Implications for understanding maltreated children's eyewitness memory are discussed.  相似文献   
840.
A three-factor model of personality pathology was investigated in a clinical sample of 183 female patients in an outpatient eating disorders treatment program. Cluster analysis of MCMI-II personality scales (Millon, 1987) yielded three distinct personality profiles, which were consistent with previous studies. First, 16.9% of the sample comprised a High Functioning cluster, which manifested no clinical elevations on the MCMI-II and had significantly lower scores on the Eating Disorder Inventory (EDI; Garner; 1991) scales than the other two clusters. Second, 49.1% of the sample comprised an Undercontrolled/Dysregulated cluster. Finally, the remaining 34% of the sample comprised an Overcontrolled/Avoidant cluster. This final cluster had significantly higher EDI Ineffectiveness scale scores than the Undercontrolled/Dysregulated cluster group. Cluster membership was not associated with eating disorder subtype, suggesting that there is considerable variance in personality pathology within eating disorder diagnostic categories.  相似文献   
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