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161.
Prism adaptation, a form of procedural learning, is a phenomenon in which the motor system adapts to new visuospatial coordinates imposed by prisms that displace the visual field. Once the prisms are withdrawn, the degree and strength of the adaptation can be measured by the spatial deviation of the motor actions in the direction opposite to the visual displacement imposed by the prisms, a phenomenon known as aftereffect. This study was designed to define the variables that affect the acquisition and retention of the aftereffect. Subjects were required to throw balls to a target in front of them before, during, and after lateral displacement of the visual field with prismatic spectacles. The diopters of the prisms and the number of throws were varied among different groups of subjects. The results show that the adaptation process is dependent on the number of interactions between the visual and motor system, and not on the time spent wearing the prisms. The results also show that the magnitude of the aftereffect is highly correlated with the magnitude of the adaptation, regardless of the diopters of the prisms or the number of throws. Finally, the results suggest that persistence of the aftereffect depends on the number of throws after the adaptation is complete. On the basis of these results, we propose that the system underlying this kind of learning stores at least two different parameters, the contents (measured as the magnitude of displacement) and the persistence (measured as the number of throws to return to the baseline) of the learned information.  相似文献   
162.
The authors tested an attribution-affect model of schizophrenic relapse attending to the role of families' positive affect (warmth) and negative affect (criticism). Coders listened to interviews of 40 family members taken from C. E. Vaughn, K. S. Synder, S. Jones, W. B. Freeman, and I. R. Falloon (1984) and rated their attributions of controllability for the symptoms and behaviors of their relatives with schizophrenia. For family members not designated as emotionally overinvolved, perceptions that their ill relatives' symptoms and behaviors were under the patients' control were related to family members' warmth and criticism and to patients' clinical outcomes. Of the affective reactions, only criticism predicted outcome. In addition, patients' use of street drugs was related to attributions, criticism, and outcome. Together these findings suggest that families' attributions and criticism are important in understanding the relationship between family factors and course of illness.  相似文献   
163.
It is not clear from the literature why, as children develop, there are important increases in memory span, the number of just-presented items that the participant can repeat in the correct serial order. To understand this, some recent results on capacity limits and processing rates were re-analyzed. We first describe results using a conventional measure of performance in immediate memory tasks that is affected by the list length (proportion correct). Next we describe results using a less conventional measure (number correct) that is unaffected by list length under circumstances in which attention to the list during its presentation is curtailed. This measure can estimate an individual's limited-capacity storage ability. Last, we examine measures of spoken response timing that do and do not change with list length. We show that unconventional measures that do not change with list length, but do change with development, are especially useful in assessing basic changes in information processing parameters, including increases in memory capacity and processing speed.  相似文献   
164.
We investigate the emergence of iconicity, specifically a bouba‐kiki effect in miniature artificial languages under different functional constraints: when the languages are reproduced and when they are used communicatively. We ran transmission chains of (a) participant dyads who played an interactive communicative game and (b) individual participants who played a matched learning game. An analysis of the languages over six generations in an iterated learning experiment revealed that in the Communication condition, but not in the Reproduction condition, words for spiky shapes tend to be rated by naive judges as more spiky than the words for round shapes. This suggests that iconicity may not only be the outcome of innovations introduced by individuals, but, crucially, the result of interlocutor negotiation of new communicative conventions. We interpret our results as an illustration of cultural evolution by random mutation and selection (as opposed to by guided variation).  相似文献   
165.
This longitudinal study was conducted among 102 women with non-metastasic breast cancer to identify the time evolution and prevalence of distress at specific times through diagnosis and treatment of disease: preliminary diagnosis, surgery, definitive diagnosis and chemotherapy. Additionally, the study aimed to examine the role of demographic, medical and psychosocial factors on distress. The results indicated that prevalence of distress was higher at initial diagnosis (25%) than the following time points (approximately 17%). The differences inter-individuals in the levels of distress were observed over the four assessments. No relation between distress and demographic and medical factors was found. However, psychosocial aspects were significant risk factors. Patterns of emotional suppression and specific coping responses like helplessness/hopelessness, anxious preoccupation, cognitive avoidance and fatalism were positively related to distress, whereas fighting spirit and perceived social support showed a protective role. Moreover, helplessness/hopelessness and anxious preoccupation jointly predicted 75% of cases and 98% non-cases of distress. Finally, a mediational model between emotional suppression and distress through helplessness/hopelessness was tested. Results support the necessity of routine distress screening all through the illness. Implications of data for psychosocial interventions with breast cancer patients are highlighted.  相似文献   
166.

Purpose  

This study investigated whether meeting electronically first using computer-mediated communication (CMC) before meeting face-to-face (FTF) increases the inclusion of a female group member in a predominantly male project team.  相似文献   
167.
The BRIEF-P is one of the most used instruments to measure Executive Function (EF). This report is aimed at showing the psychometric properties of the Catalan version of it. To do this, a random cluster sampling was carried out in Osona (Catalonia), recruiting 417 teachers and 408 parents of children aged 3 to 6 years. As with the original instrument, results show that reliability is excellent and that girls have a better EF than boys in the following areas: Working Memory, Plan/Organize, and Inhibit. Since in some areas Catalonia's preschool children show EF values slightly better than those of the reference sample, a new scale for using it in this population is provided.  相似文献   
168.
In this paper we present a new framework of idealization in biology. We characterize idealizations as a network of counterfactual and hypothetical conditionals that can exhibit different ??degrees of contingency??. We use this idea to say that, in departing more or less from the actual world, idealizations can serve numerous epistemic, methodological or heuristic purposes within scientific research. We defend that, in part, this structure explains why idealizations, despite being deformations of reality, are so successful in scientific practice. For illustrative purposes, we provide an example from population genetics, the Wright-Fisher Model.  相似文献   
169.
Diagnostic tests are available to detect several mutations related to adult-onset, autosomal dominant, neurodegenerative diseases. We aimed to describe our experience in a presymptomatic testing program run by the Brazilian Public Health System from 1999 to 2009. A total of 184 individuals were eligible for presymptomatic testing due to a risk for spinocerebellar ataxia (SCA) - SCA3 (80%), Huntington’s disease (11.9%), familial amyloidotic neuropathy (4.3%), SCA1, SCA2, SCA6, or SCA7. Most were women (70%), married (54%), and had children prior to presymptomatic testing (67%). Their mean age at entrance was 34 (SD = 11 years). Educational level was above the average Brazilian standard. After receipt of genetic counseling, 100 individuals (54%) decided to undergo testing; of these, 51 were carriers. Since no individual returned for post-test psychological evaluation, we conducted a subsequent survey, unrelated to test disclosures. We contacted 57 individuals of whom 31 agreed to participate (24 had been tested, 7 had not). Several ascertainment concerns relating to these numerous losses prevented us from generalizing our results from this second survey. We concluded that: decision-making regarding presymptomatic testing seems to be genuinely autonomous, since after genetic counseling half the individuals who asked for presymptomatic testing decided in favor and half decided against it; general characteristics of Brazilians who sought presymptomatic testing were similar to many European samples studied previously; and individuals at risk for SCA3 may be at greater risk of depression. Although no clear-cut reason emerged for rejection of follow-up psychological sessions after presymptomatic testing, this finding suggests adjustments to our presymptomatic testing program are necessary.  相似文献   
170.
The purpose of this study was to examine parents’ attitudes about and patterns of providing financial assistance to their children during college, and how varying levels of parental financial support were related to children’s beliefs (e.g., perceptions of adulthood), behaviors (e.g., work hours, drinking, and drug use), and identity development. The sample consisted of 402 undergraduate students (62% women) recruited from four college sites across the United States (M age = 19.89), and one of their parents (310 mothers and 92 fathers). Using cluster analysis, results suggested four distinct approaches to parental financial involvement and found that emerging adults’ beliefs, behaviors, and identity development differed as a function of parents’ cluster membership. Discussion focuses on implications for emerging adult children whose parents endorse varying levels of financial involvement.  相似文献   
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