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51.
Ten subjects served as their own controls in two conditions of continuous, centrifugally produced hypergravity (+2 Gz) and a 1-G control condition. Before and after exposure, open-loop measures were obtained of (1) motor control, (2) visual localization, and (3) hand-eye coordination. During exposure in the visual feedback/hypergravity condition, subjects received terminal visual error-corrective feedback from their target pointing, and in the no-visual feedback/hypergravity condition they pointed open loop. As expected, the motor control measures for both experimental conditions revealed very short lived underreaching (the muscle-loading effect) at the outset of hypergravity and an equally transient negative aftereffect on returning to 1 G. The substantial (approximately 17°) initial elevator illusion experienced in both hypergravity conditions declined over the course of the exposure period, whether or not visual feedback was provided. This effect was tentatively attributed to habituation of the otoliths. Visual feedback produced a smaller additional decrement and a postexposure negative aftereffect, possible evidence for visual recalibration. Surprisingly, the target-pointing error made during hypergravity in the no-visual-feedback condition was substantially less than that predicted by subjects’ elevator illusion. This finding calls into question the neural outflow model as a complete explanation of this illusion.  相似文献   
52.
Considerable scientific evidence demonstrates the reduction in risk for neural tube defects (NTDs) associated with maternal preconceptional folic acid supplementation. The National Society of Genetic Counselors (NSGC) endorses the U.S. Public Health Service recommendations for folic acid supplementation at the 0.4 mg level for women in the general population and at the 4.0 mg level for women at high or increased risk for NTD pregnancies for at least 4 weeks prior to active pursuit of conception. We encourage targeted educational efforts and surveillance to assess results of this dietary supplementation. The NSGC further urges the Food and Drug Administration to fortify staple foodstuffs with folic acid for a population-based approach to minimize the number of NTD births.  相似文献   
53.
The current investigation examined the degree to which judges' ratings of skill, anxiety, and attractiveness are influenced by the responsivity of the confederate. High-, medium-, and low-skilled subject-pool groupings, as well as self-referred clinical groups, were exposed to either a moderately or a minimally responsive confederate. Results indicated that subjects were rated as more skillful when interacting with a moderately responsive confederate than when interacting with a minimally responsive confederate. Further, there was a groups × condition interaction for anxiety ratings such that both the high- and the medium-skilled groups appeared more anxious under the minimal condition, whereas the low-skilled and self-referred groups did not. Self-referred subjects received significantly lower attractiveness ratings than did the high- or medium-skilled groups. Implications of these results and future directions for research are discussed.This research is based on a M.S. thesis carried out by the first author under direction of the second author.  相似文献   
54.
Prominence of the brain's right-hemisphere information processing and intensity of dream experience are two theoretically related constructs that have been proposed as important psychological aspects of REM sleep. Either view is consistent with the prediction that the effect of REM deprivation will depend in part on the nature of cognitive activity that is initiated at the onset of each REM period and that "substitutes" for the interrupted REM process. In the present study, the effect of REM deprivation was more striking for female subjects given a digits task than for female subjects given a fantasy-reporting task during awakening used to induce REM deprivation for the first 6 hours of the night. High neuroticism appeared to exaggerate the effect. No corresponding pattern was observed for the male subjects. These preliminary finding may be exaggerated by cognitive activity that is functionally incongruent with those processes. The results also raise interesting questions about individual differences.  相似文献   
55.
56.
This article takes a sociological approach to a problem that has usually been considered as a psychological phenomenon. It addresses the problem of male—female interactions in work situations utilizing the organizational concepts of division of labor and legitimacy. Traditional explanations evoking sex-role socialization are reviewed and rejected for purposes of experimentation and intervention. An alternative argument, focusing on the structural arrangements of organizational settings, is presented as an explanation for behavioral effects previously attributed to inherent sex differences. The results of a pilot study are briefly described, and directions for further experimentation and possible intervention strategies are suggested.The bibliographic search and initial conceptualization of this research was supported by a grant from the Ford Foundation under the auspices of the Center for Research on Women at Stanford University. We are grateful to Miriam Rosen for much of the bibliographic work. The pilot study was supported in part by funds from the Guggenheim Foundation and by a grant from the Spencer Foundation. We also wish to thank Richard Torres and Christie Timberlake for their invaluable assistance on this project.  相似文献   
57.
Forty-eight graduate and undergraduate students between 17 and 30 years of age judged the size of the central circle in Ebbinghaus figures presented under either simultaneous or successive viewing conditions. Successive presentation eliminated the illusion produced by the normally overestimated figure and diminished that produced by the underestimated figure. Under simultaneous viewing conditions, increasing the number of surrounding circles reduced the magnitude of the reversed illusion produced by the normally overestimated figure but had no effect on the illusion produced by the underestimated figure. Under successive viewing conditions, increasing the number of surrounding circles had no effect on the magnitude of illusion produced by the normally overestimated figure but increased the illusion produced by the underestimated figure. These data were interpreted as inconsistent with a size contrast explanation of the Ebbinghaus illusions and suggested that these illusions may be produced by a contour interaction process.  相似文献   
58.
One solution to the difficulty of running real-time applications under UNIX is to develop the application programs on an available UNIX system and execute them on a dedicated satellite processor. This combines the advantages of a powerful timesharing operating system with the real-time capabilities of a single-process system. PARASITE, a real-time satellite system, provides tools for developing the application program on the host and executing it on a satellite. A host utility serves to invoke the standard UNIX C compiler and link its output with the PARASITE library. The PARASITE library consists of routines that mimic the standard library and routines that read and write the real-time peripherals. PARASITE currently supports digital inputs and outputs, asynchronous serial-line interfaces, program-mable real-time clocks, and analog-to-digital and digital-to-analog converters. Another PARA-SITE utility downloads the object code of the user program and PARASITE support code into the satellite, where it runs independently. Once the application routine is executing on the satellite, it controls the satellite processor at all times and is continuously available for servicing hardware-generated interrupts. When a real-time peripheral interrupt routine is invoked by a hardware interrupt, it sends a software signal to the user program, in addition to processing the interrupt. This allows the user program to perform additional tasks that are specific to the application. All data to be permanently stored must be transferred to the host. Since the satellite has no direct access to the resources of the host, a process running on the host receives the data and manages files. PARASITE provides packet driver routines on both the host and the satellite, which together handle the data transmission protocol.  相似文献   
59.
Most psychological tests and inventories, particularly in personality and attitude measurement, contain common items, that is, various subscales of the test or inventory may share one or more items in common. Surprisingly, the role of common items in such a fundamental personality test attribute as reliability is not known. The present report specifically considered common-item contributions to test internal consistency reliability using extant data from the California Psychological Inventory. No negative contribution of item overlap was found. To the contrary, it was concluded that the use of common items is an economical technique for increasing the total number of items in the scales, thus increasing scale internal reliabilities without increasing the overall number of items in the inventory.  相似文献   
60.
This study examined the generalization and maintenance effects of three phases of parent training (Instructions plus Feedback and two Self-management Training phases) on levels of disruptive child behavior and the accuracy with which parents implemented programs. Data were collected from five families in three main settings: the initial training setting (the home), a variety of generalization settings in the community, and the family breakfast. A multiple baseline across subjects design was used. Instructions plus Feedback comprised instructing parents to use a range of behavior management procedures and provided home-based differential feedback concerning accuracy of program implementation. Self-management Training phases involved training parents in goal setting, self-monitoring, and planning skills, specific to their performance of appropriate parenting skills in generalization settings. Results indicated that the Instructions plus Feedback phase was sufficient to produce reduced levels of problem behavior at home and high levels of accurate implementation, but generalization effects out of home were equivocal. Self-management maintained reduced levels of problem behavior at home but, in addition, resulted in generalization effects in community settings for both children and parents. Maintenance probes 3 months following the program revealed the effects had been maintained.  相似文献   
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