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81.
This article examines the statistical determinants of risk preference. In a meta-analysis of animal risk preference (foraging birds and insects), the coefficient of variation (CV), a measure of risk per unit of return, predicts choices far better than outcome variance, the risk measure of normative models. In a meta-analysis of human risk preference, the superiority of the CV over variance in predicting risk taking is not as strong. Two experiments show that people's risk sensitivity becomes strongly proportional to the CV when they learn about choice alternatives like other animals, by experiential sampling over time. Experience-based choices differ from choices when outcomes and probabilities are numerically described. Zipf's law as an ecological regularity and Weber's law as a psychological regularity may give rise to the CV as a measure of risk.  相似文献   
82.
To explore the influence of client characteristics in premarital counseling, a five factor model is presented that includes the social context, family-of-origin influences, individual characteristics, couple interactional processes, and motivation for attending premarital counseling. The findings demonstrate that providers believe that many client characteristics influence the degree to which couples benefit from premarital counseling. Providers rated the influence of the client characteristic factors in the following order (from most to least influential): couple interactional processes, family-of-origin influences, individual characteristics, motivation for premarital counseling, and the social context. Recommendations for future theory development, practice, and research are discussed.The findings presented in this article were part of the authors doctoral dissertation at the University of Florida.  相似文献   
83.
Locomotion,incidental learning,and the selection   总被引:2,自引:0,他引:2  
In three experiments, we examined the effects of locomotion and incidental learning on the formation of spatial memories. Participants learned the locations of objects in a room and then made judgments of relative direction, using their memories (e.g., "Imagine you are standing at the clock, facing the jar. Point to the book"). The experiments manipulated the number of headings experienced, the amount of interaction with the objects, and whether the participants were informed that their memories of the layout would be tested. When participants were required to maintain a constant body orientation during learning (Experiment 1), they represented the layout in terms of a single reference direction parallel to that orientation. When they were allowed to move freely in the room (Experiment 2), they seemed to use two orthogonal reference axes aligned with the walls of the enclosing room. Extensive movement under incidental learning conditions (Experiment 3) yielded a mixture of these two encoding strategies across participants. There was no evidence that locomotion, interaction with objects, or incidental learning led to the formation of spatial memories that differed from those formed from static viewing.  相似文献   
84.
This article reviews some of our recent functional magnetic resonance imaging (fMRI) studies of stuttering. Using event-related fMRI experiments, we investigated brain activation during speech production. Results of three studies comparing persons who stutter (PWS) and persons who do not stutter (PWNS) are outlined. Their findings point to a region in the right frontal operculum (RFO) that was consistently implicated in stuttering. During overt reading and before fluency shaping therapy, PWS showed higher and more distributed neuronal activation than PWNS. Immediately after therapy differential activations were even more distributed and left sided. They extended to frontal, temporal, and parietal regions, anterior cingulate, insula, and putamen. These over-activations were slightly reduced and again more right sided two years after therapy. Left frontal deactivations remained stable over two years of observation, and therefore possibly indicate a dysfunction. After therapy, we noted higher activations in persons who stutter moderately than in those who stutter severely. These activations might reflect patterns of compensation. We discuss why these findings suggest that fluency-inducing techniques might synchronize a disturbed signal transmission between auditory, speech motor planning, and motor areas.

Educational objectives: The reader will learn about and be able to: (1) identify regions of brain activations and deactivations specific for PWS; (2) describe brain activation changes induced by fluency shaping therapy; and (3) discuss the correlation between stuttering severity and brain activation.  相似文献   

85.
The central issue addressed is whether there are electrophysiological markers for high-language proficiency in adults. Event-related brain potentials (ERPs) were recorded in 19 young adults who demonstrated either "normal" or "high" language proficiency. ERPs were obtained during a sentence-processing task and analyzed for specific response components elicited by different word types. The ERPs in the normal and high-language proficiency groups were similar for early sensory related processing but differed in the later components thought to be more closely related to lexical access and post-lexical processing. The findings for the ERP waveforms suggest that adults with high-language proficiency show slightly faster lexical access over left anterior brain regions for closed class items, and a reduced reliance on contextual information contained in sentences.  相似文献   
86.
The distinction between the processing of musical information and segmental speech information (i.e., consonants and vowels) has been much explored. In contrast, the relationship between the processing of music and prosodic speech information (e.g., intonation) has been largely ignored. We report an assessment of prosodic perception for an amateur musician, KB, who became amusic following a right-hemisphere stroke. Relative to matched controls, KB's segmental speech perception was preserved. However, KB was unable to discriminate pitch or rhythm patterns in linguistic or musical stimuli. He was also impaired on prosodic perception tasks (e.g., discriminating statements from questions). Results are discussed in terms of common neural mechanisms that may underlie the processing of some aspects of both music and speech prosody.  相似文献   
87.
This study of Chinese, Japanese, and Korean immigrant junior high and high school students (N = 319) investigated the association between age, acculturation, cultural adjustment difficulties, and general mental health concerns. Hierarchical regression analyses determined that among all of the independent variables, age, acculturation, and cultural adjustment difficulties had significant predictive effects on mental health symptoms. Implications for theory, research, and practice are addressed, particularly as they relate to developmental issues among immigrant youths.  相似文献   
88.
Data from two multi-ethnic prospective studies of African American, Latina, and non-Hispanic White pregnant women were used to examine the influence of contextual factors on social support processes during pregnancy. Multiple types of support (perceived support, received support, support satisfaction, network support) and sources of support (baby's father, family, friends) were assessed. The role of ethnicity in social support was examined after controlling for the contribution of related contextual factors (SES, marital status, age, parity, employment) to these processes. The impact of ethnicity and related contextual factors differed across sources of social support. Ethnic differences in support from family and friends, but not from the baby's father, emerged. However, marital status was a consistent predictor of support from the baby's father, and SES was a consistent predictor of support from friends. Overall, the findings of two studies suggest that although ethnicity is associated with support from friends and family, other contextual factors, such as marital status and SES, influence support processes during pregnancy.  相似文献   
89.
The functional role of NCAM gene expression in memory formation was studied in the one-trial passive avoidance task in day-old chicks by pretraining injections of one of three different 18-mer end-protected oligonucleotides corresponding to positions 190-, 207-, and 332- of the NCAM Ig1 domain. Twenty-four-hour-old chicks were trained by pecking at a bitter-tasting bead and tested for avoidance 30 min, 3, 8, or 24 hr later. Memory retention was significantly reduced only in the group of animals injected with the NCAM antisense corresponding to position 207- (AS-ODN-207), and only if given twice, both immediately after hatching and 12 hr before training. This antisense was without effect on the general behavior of the chicks, training or acquisition, and did not produce observable neurotoxic damage. Under such conditions amnesia was evident by 3 hr after training and lasted until at least 24 hr after training. The two other tested oligonucleotides were without behavioral effect. To control for nonsequence-specific effects of AS-ODN-207, brains from injected and trained animals were processed for Western blotting and probed using anti-NCAM, anti-L1, and anti-actin antibodies. NCAM antisense corresponding to position 207- significantly reduced the level of NCAM, whereas the level of L1 and actin remained unchanged. These results confirm our earlier conclusion that NCAM is necessary for longer term memory retention.  相似文献   
90.
Development and utilization of two self-efficacy measures thought to be relevant to stressed family caregivers, Caregiver Self-Care Self-Efficacy and Caregiver Problem-Solving Self-Efficacy, are described. Data obtained in the context of a psychoeducational intervention program are available for 217 caregivers of frail and/or cognitively impaired elders. Analyses of psychometric properties of the efficacy measures demonstrate good internal consistency and test-retest reliability for both measures. In addition, both measures of self-efficacy are related to depression as measured by the Beck Depression Inventory and caregiver distress as measured by the Zarit Burden Scale. Problem-Solving Self-efficacy also is related to subjective caregiver burden as measured by Zarit's Memory and Behavior Problem Checklist. Results are promising in terms of the utility of the measure and the application of self-efficacy theory to the caregiving situation. Limitations of these measures are discussed and suggestions made for improved second-generation self-efficacy scales.  相似文献   
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