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861.
Contemporary findings reveal that the multiple modes of autonomic control do not lie along a single continuum extending from parasympathetic to sympathetic dominance but rather distribute within a 2-dimensional space. The physiological origins and empirical documentation for the multiple modes of autonomic control are considered. Then a formal 2-dimensional conception of autonomic space is proposed, and a quantitative model for its translation into a functional output surface is derived. It is shown that this model (a) accounts for much of the error variance that has traditionally plagued psychophysiological studies, (b) subsumes psychophysiological principles such as the law of initial values, (c) gives rise to formal laws of autonomic constraint, and (d) has fundamental implications for the direction and interpretation of a wide array of psychophysiological studies.  相似文献   
862.
Task dynamics corresponding to rhythmic movements emerge from interactions among dynamical resources composed of the musculature, the link segments, and the nervous and circulatory systems. This article investigated whether perturbations of interlimb coordination might be effect over circulatory and nervous elements. Stiffness of wrist-pendulums oscillated at a common tempo and at 180 degrees relative phase was perturbed through the use of tonic activity about an ankle. Left and right stiffnesses, the common period, and the phase relation all changed. Stiffnesses increased with ankle torque in proportion to the wrist's inertial load. Despite different changes in stiffness at the two wrists, isochrony was preserved. The stability was shown to be consistent with the proportionality of changes in stiffness to the inertial loads. The phase departed from antiphase in proportion to the asymmetry of inertial loads. The size of departures decreased with increasing ankle torque. An account was developed in terms of muscular, circulatory, and nervous functions.  相似文献   
863.
864.
Pseudohomophones were used in a primed naming task. In Experiments 1 and 2, target pseudowords that sounded like real words (e.g., CHARE) were preceded either by context words that related associatively to the word with which the target was homophonic (TABLE-CHARE) or by context words that were not associatively related (NOVEL-CHARE). Control pairs were TABLE-THARE and NOVEL-THARE (Experiment 1) and TABLE-CHARK and NOVEL-CHARK (Experiment 2). In relation to NOVEL, TABLE benefited the naming of CHARE but not the naming of THARE or CHARK. TAYBLE-CHAIR pairs were used in Experiment 3. If the prime TAYBLE activated/table/,then/chair/would be activated associatively and the target CHAIR would be named faster than if TARBLE was the prime. Experiment 4 extended the design of Experiment 3 to include TABLE-CHAIR pairs and a comparison of a short (280 ms) and a long (500 ms) delay between context and target onsets. The priming due to associated pseudohomophones was unaffected by onset asynchrony and equal in magnitude to that due to associated words. Results suggest that lexical representations are coded and accessed phonologically.  相似文献   
865.
Strings of 4 unrelated letters were backward masked at varying durations to examine 3 major issues. (a) One issue concerned relational features. Letters with abnormal relations but normal elements were created by interchanging elements between large and small normal letters. Overall accuracy was higher for letters with normal relations, consistent with the idea that relational features are important in recognition. (b) Interpattern relations were examined by mixing large and small letters within strings. Relative to pure strings, accuracy was reduced, but only for small letters and only when in mixed strings. This effect can be attributed to attentional priority for larger forms over smaller forms, which also explains global precedence with hierarchical forms. (c) Forced-choice alternatives were manipulated in Experiments 2 and 3 to test feature integration theory. Relational information was found to be processed at least as early as feature presence or absence.  相似文献   
866.
Immediate and delayed transfer of training effects in statistical reasoning   总被引:2,自引:0,他引:2  
Ss were trained on the law of large numbers in a given domain through the use of example problems. They were then tested either on that domain or on another domain either immediately or after a 2-week delay. Strong domain independence was found when testing was immediate. This transfer of training was not due simply to Ss' ability to draw direct analogies between problems in the trained domain and in the untrained domain. After the 2-week delay, it was found that (a) there was no decline in performance in the trained domain and (b) although there was a significant decline in performance in the untrained domain, performance was still better than for control Ss. Memory measures suggest that the retention of training effects is due to memory for the rule system rather than to memory for the specific details of the example problems, contrary to what would be expected if Ss were using direct analogies to solve the test problems.  相似文献   
867.
Self-management of diabetes mellitus: a critical review   总被引:5,自引:0,他引:5  
Diabetes has no known cure and is a leading source of morbidity and mortality. Clinical management involves patients managing a complex and variable regimen. This article reviews the determinants of effective self-management and the methods of promoting better self-management. Trait variables (e.g., personality and demographics) have been presumed to affect self-management, but evidence suggests they have little impact. The important determinants of self-management are transient situational factors such as psychological stress and social pressure to eat. Interventions to promote better self-management have reported initial improvements in blood glucose control, but the long-term effects are unclear. We conclude that self-management has been inadequately assessed and that attempts to improve self-management have relied excessively on providing information. More research is needed to clarify determinants of self-management, and interventions to improve self-management will need to change these determinants.  相似文献   
868.
This study examined the relationships among five measures that assess various cognitive components of the child's acquisition of gender. At around 2 years of age, children were given a task assessing their ability to accurately label as a boy or a girl some head-and-shoulders pictures of boys and girls. At 4 years of age, these children were given tasks measuring (1) the degree to which they found gender a salient parameter of categorization, (2) the amount of gender-related knowledge they could display (SERLI-SRD), (3) the degree to which their preferences were gender-typed (SERLI-SRP) and (4) the accuracy of their memory for gender-typed information. There was no consistent pattern of relationship among the children's scores on these five tools for measuring gender acquisition. Our findings suggest that gender is a multidimensional construct in children's development, and thus these results challenge the undimensional manner in which gender is repeatedly addressed in developmental theory and research.This research was funded in part by a federal biomedical research grant (No. 2507RR07080) awarded to the first author from the Department of Psychology at the University of Oregon, and by Grant No. RO1HD175751 from the National Institute of Child Development awarded to the third author.We wish to thank Margo Lane, Rachel Robertson, Jacqui Oucalt, Laura Baker, Dale Roberts, and the teachers, parents, and assistants of the Child Research Laboratory at the University of Oregon in Eugene, Oregon, for their invaluable contribution to this research.  相似文献   
869.
This study examined the effects of personal religious orientation, religious denomination, and gender on attitudes toward women and their work roles using a sample of 263 single undergraduate university students. Subjects with a high intrinsic religious orientation put significantly more emphasis on family than career in their anticipated general lifestyle relative to those with a low intrinsic religious orientation. Subjects with a high intrinsic religious orientation were also more likely to anticipate the female spouse spending less time in a profession during the children's early years. Males showed more traditional attitudes toward women than females, but there were no gender effects on measures of preferred general lifestyle, preferred child-care distribution, or preferred career involvement for the wife. Subjects belonging to mainline and conservative denomination did not differ significantly in their attitudes toward women or their work roles.  相似文献   
870.
Proboscis extension conditioning of honeybee workers was used to test the ability of bees to respond to appetitive and aversive stimuli while restrained in a harness that allows subjects to move their antennae and mouthparts (Kuwabara, 1957; Menzel, Erber, & Masuhr, 1974). Subjects were conditioned to discriminate between two odors, one associated with sucrose feeding and the other associated with a 10 V AC shock if they responded to the sucrose unconditioned stimulus (US) in the context of that odor. Most Ss readily learned to respond to the odor followed by sucrose feeding and not to the odor associated with sucrose stimulation plus shock. Furthermore, in the context of the odor associated with shock, significantly more subjects withheld or delayed proboscis extension on stimulation with the sucrose US than they did in the context of the odor associated with feeding. Thus, restrained honeybees can readily learn to avoid shock according to an odor context by withholding proboscis extension to a normally powerful releaser. Analysis of individual learning curves revealed that subjects differed markedly in performance on this task. Some learn the discrimination quickly, whereas others show different kinds of response patterns.  相似文献   
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