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111.
During the first year of life, infants begin to have difficulties perceiving non‐native vowel and consonant contrasts, thus adapting their perception to the phonetic categories of the target language. In this paper, we examine the perception of a non‐segmental feature, i.e. stress. Previous research with adults has shown that speakers of French (a language with fixed stress) have great difficulties in perceiving stress contrasts ( Dupoux, Pallier, Sebastián & Mehler, 1997 ), whereas speakers of Spanish (a language with lexically contrastive stress) perceive these contrasts as accurately as segmental contrasts. We show that language‐specific differences in the perception of stress likewise arise during the first year of life. Specifically, 9‐month‐old Spanish infants successfully distinguish between stress‐initial and stress‐final pseudo‐words, while French infants of this age show no sign of discrimination. In a second experiment using multiple tokens of a single pseudo‐word, French infants of the same age successfully discriminate between the two stress patterns, showing that they are able to perceive the acoustic correlates of stress. Their failure to discriminate stress patterns in the first experiment thus reflects an inability to process stress at an abstract, phonological level.  相似文献   
112.
It is assumed that spatial memory contributes crucially to animal cognition since animals’ habitats entail a large number of dispersed and unpredictable food sources. Spatial memory has been investigated under controlled conditions, with different species showing and different conditions leading to varying performance levels. However, the number of food sources investigated is very low compared to what exists under natural conditions, where food resources are so abundant that it is difficult to precisely identify what is available. By using a detailed botanical map containing over 12,499 trees known to be used by the Taï chimpanzees, we created virtual maps of all productive fruit trees to simulate potential strategies used by wild chimpanzees to reach resources without spatial memory. First, we simulated different assumptions concerning the chimpanzees’ preference for a particular tree species, and, second, we varied the detection field to control for the possible use of smell to detect fruiting trees. For all these assumptions, we compared simulated distance travelled, frequencies of trees visited, and revisit rates with what we actually observed in wild chimpanzees. Our results show that chimpanzees visit rare tree species more frequently, travel shorter distances to reach them, and revisit the same trees more often than if they had no spatial memory. In addition, we demonstrate that chimpanzees travel longer distances to reach resources where they will eat for longer periods of time, and revisit resources more frequently where they ate for a long period of time during their first visit. Therefore, this study shows that forest chimpanzees possess a precise spatial memory which allows them to remember the location of numerous resources and use this information to select the most attractive resources.  相似文献   
113.
In the present study, we examined whether preparing motor responses under different emotional conditions alters motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation delivered to the motor cortex. Analyses revealed three findings: (1) Reaction times were expedited during exposure to unpleasant images, as compared with pleasant and neutral images; (2) force amplitude was greater during exposure to unpleasant images, as compared with pleasant and neutral images; and (3) MEPs were larger while participants viewed unpleasant images, as compared with neutral images. Hence, coupling the preparation of motor responses with the viewing of emotional images led to arousal-driven changes in corticospinal motor tract excitability, whereas movement speed and force production varied as a function of emotional valence. These findings demonstrate that the effects of emotion on the motor system manifest at varying sensitivity levels across behavioral and neurophysiological measures. Moreover, they validate the action readiness component of emotional experience by demonstrating that emotional states influence the execution of future movements but, alone, do not lead to overt movement.  相似文献   
114.
Genetic studies of stuttering in a founder population   总被引:2,自引:0,他引:2  
Genome-wide linkage and association analyses were conducted to identify genetic determinants of stuttering in a founder population in which 48 individuals affected with stuttering are connected in a single 232-person genealogy. A novel approach was devised to account for all necessary relationships to enable multipoint linkage analysis. Regions with nominal evidence for linkage were found on chromosomes 3 (P=0.013, 208.8 centiMorgans (cM)), 13 (P=0.012, 52.6 cM), and 15 (P=0.02, 100 cM). Regions with nominal evidence for association with stuttering that overlapped with a linkage signal are located on chromosomes 3 (P=0.0047, 195 cM), 9 (P=0.0067, 46.5 cM), and 13 (P=0.0055, 52.6 cM). We also conducted the first meta-analysis for stuttering using results from linkage studies in the Hutterites and The Illinois International Genetics of Stuttering Project and identified regions with nominal evidence for linkage on chromosomes 2 (P=0.013, 180-195 cM) and 5 (P=0.0051, 105-120 cM; P=0.015, 120-135 cM). None of the linkage signals detected in the Hutterite sample alone, or in the meta-analysis, meet genome-wide criteria for significance, although some of the stronger signals overlap linkage mapping signals previously reported for other speech and language disorders. EDUCATIONAL OBJECTIVES: After reading this article, the reader will be able to: (1) summarize information about the background of common disorders and methodology of genetic studies; (2) evaluate the role of genetics in stuttering; (3) discuss the value of using founder populations in genetic studies; (4) articulate the importance of combining several studies in a meta-analysis; (5) discuss the overlap of genetic signals identified in stuttering with other speech and language disorders.  相似文献   
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Four commonly used operationalizations of the social support concept: network contact frequency, satisfaction with support (including nine dimensions), perceived availability of support, and use of support, were related to two measures of psychological adjustment (Beck Depression Inventory and Symptom Checklist-90) and to one measure of physical adjustment (Cornell Medical Index). Subjects were 68 45- to 85-year-old, highly stressed care-givers to spouses with Alzheimer's disease. Results indicate that of the four operationalizations, Satisfaction with Support was the only significant predictor of depression and general psychopathology. The set of four support variables showed the strongest relationship to depression level, next strongest to general psychopathology, and least to physical health. The satisfaction with nine social support dimensions related differentially to the types of adjustment. Results suggest the importance of specificity (sample, support operationalization, dimensions, adjustment measures) in social support research.  相似文献   
118.
The Beck Anxiety Inventory (BAI) has become a popular measure in anxiety assessment and the BAI does not overlap in content with measures of depression. There is also some factor analytic evidence to support this distinction. However, an inspection of the BAI's content indicates that many of its items resemble, or are identical to, the symptoms of panic attacks listed in the DSM-IV. Further empirical support for this suspicion is provided from the results of a factor analysis of the BAI items and the individual DSM-IV panic symptoms contained in the Panic Attack Questionnaire, using data from a sample of 157 panic disorder patients. A three-factor model (dizziness related, catastrophic cognitions/fear, cardiorespiratory distress) emerged that replicated a three-factor model of panic symptoms identified in earlier work with another panic disorder sample. All but one of the BAI items loaded highly on the three panic symptom clusters and no separate BAI factor was obtained. The BAI appears to be confounded with, or actually measures, panic attacks rather than anxiety in general. Several implications of this finding are discussed.  相似文献   
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120.
The evidence indicates that adolescent depression may be more difficult to recognize than its adult counterpart, although the reasons for this difficulty remain unclear. The research in this area is in part impeded by the lack of adolescent-specific measures of personality functioning. In this study the personality styles, expressed concerns, and behavioral tendencies of depressed adolescents were investigated by means of the Millon Adolescent Personality Inventory (MAPI), a relatively new personality inventory designed specifically for this age group. Three hundred sixty-six high school students completed the Beck Depression Inventory (BDI) and the MAPI, resulting in 332 valid and reliable MAPI profiles. The data were reduced to two factors, accounting for 65.1% of the total variance, by means of a principal components analysis. The two factors were interpreted as two dimensions of personality functioning associated with depression in adolescents. The first dimension suggested a socially withdrawn, overtly recognizable depression, whereas the second presents acting-out tendencies that may overshadow depressive symptomatology. The findings are integrated with the theoretical positions represented in the literature. Theoretical and practical implications for the use of the MAPI with depressed adolescents are discussed.  相似文献   
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