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91.
Microcomputers can serve as automated testing stations for use in psychometric assessment. There are economic advantages in conducting aptitude and intelligence testing with such stations. It is possible to improve the quality of cognitive assessment by extending the range of cognitive abilities to be assessed? Two types of extension are considered; modifying and expanding testing procedures for psychological functions that are components of conventional tests, and the extension oof testing to psychological functions not generally assessed by conventional intelligence or aptitude tests. Computerized presentations will make relatively little difference in our ways of testing verbal comprehension. Computer controlled testing could well extend the ways in which we evaluate spatial-visual reasoning and memory. The impact of testing on the evaluation of reasoning is unclear. Computer-controlled item presentation makes it possible to conceive of tests of learning and attention, neither of which are evaluated in most psychometric programs today. The psychological nature of the abilities being assessed raises problems in assessment that are not addressed by the fact oof computer-control. Some research questions are identified that ought to be explored before testing is extended into these fields. Computer-controlled evaluation could be extended to the assessment of criterion performance, either in the normal working situation or in a simulation of the workplace. While evaluation of this sort does raise social questions, it clearly presents an opportunity to obtain validation data for psychological assessment studies.  相似文献   
92.
While many studies have attempted to produce hypertension through the use of various environmental Stressors, few have succeeded in producing chronic elevations in blood pressure beyond levels considered to be borderline hypertensive (140–160 mm Hg systolic). The problem with most studies stems from the use of genetically normotensive animals and the selection of Stressors to which animals readily adapt. A new approach is suggested, which recognizes the role of genetics in human essential hypertension. Animals with one hypertensive parent do not develop spontaneous hypertension but show a more sensitive cardiovascular response to environmental Stressors than animals with normotensive parents. Preliminary studies revealed that animals with a mixed genetic history of hypertension develop spontaneous borderline hypertension. When subjected to shock-shock conflict, these borderline hypertensive rats (BHR) developed permanent hypertension that failed to abate even after a ten-week, shock-free recovery period. The hypertension was accompanied by elevated heart weight to body weight ratios and by significant cardiac pathology. Subsequent work has demonstrated that these animals also become hypertensive when fed a high-sodium diet. Finally, in a series of exercise studies, we found that BHRs subjected to a shock stressor were protected against stress-induced hypertension if they exercised daily. The potential of this model for studies of the mechanisms by which environmental variables produce permanent hypertension is discussed.  相似文献   
93.
Two experiments examined appetitive differential conditioning of the rabbit’s jaw movement response (JMR) in a two-phase procedure. The first phase entailed reinforced training with one conditioned stimulus (CS+), and the second phase involved intermixed presentations of CS+ and an unreinforced stimulus (CS?). In Experiment 1, CS+ was a 600-Hz tone, and CS-was either a 660-,1,000-, or 2,100-Hz tone. In Experiment 2, the magnitude of the water unconditioned stimulus (US) paired with CS+ was either 1, 3, or 9 ml. The experiments revealed that 1) the level of responding to CS-rose for several days and then declined over the remainder of training; 2) the physical similarity between CS+ and CS?directly affected the level of responding to CS?but had no discernable effect on the level of responding to CS+ ; and 3) US magnitude positively affected the level of responding to CS + and, to a lesser extent, CS?. The results are discussed in terms of their implications for Spence’s gradient interaction theory and Pavlov’s external inhibition hypothesis.  相似文献   
94.
95.
This study was designed to identify the phase of rapid aimed movements responsible for hand differences in motor skill, and to evaluate potential differences between the hands in accommodating to greater accuracy demands. In both experiments, an accelerometer mounted on a stylus allowed key changes in acceleration to be used to partition the movement into phases. In Experiment 1, slower left hand movement times were attributable primarily to a terminal homing-in phase, especially as target size decreased. Since error rates varied as a function of hand and target size, speed-accuracy trade-offs may have occurred. Experiment 2 rigidly controlled error rate and confirmed the major hand difference to occur in the latter phase of the movement where error correction is presumed. Although less pronounced, adjustments were made in the earlier movement phases as well. Accommodation to greater accuracy demands involved moving the stylus closer to the target before decelerating to engage in error correction. This adjustment to gain enhanced precision was more pronounced in the left hand.  相似文献   
96.
Plasma concentrations of imipramine and amitriptyline and their desmethylated metabolites were measured in 20 children being treated for major depressive illness 2 wk. and 5 to 10 wk. after achieving drug dosages of 2.25 mg/kg body weight. At 2 wk. all children had exhibited clinical improvement, but by 10 wk. 4 of the 10 children treated with imipramine and 5 of the 10 children treated with amitriptyline had experienced clinical relapse of depressive symptoms. Tricyclic antidepressant plasma concentrations and ratios were comparable in the subgroups of children who maintained their clinical improvement and those who relapsed. There was no evidence of a systematic decline in plasma tricyclic antidepressant concentrations in those children who relapsed.  相似文献   
97.
We present four cases of Prader-Willi syndrome. Two of them have an abnormality of a chromosome 15, the other both show different chromosomal abnormalities. Translocations or deletions were found recently in the bands 15q11/12 in about 60% of the cases of Prader-Willi syndrome. The consequences for diagnosis, symptomatology and genetic counselling of the syndrome are discussed.  相似文献   
98.
99.
This study examined two issues related to the use of nonprofessional counselors (n = 159) within the context of a diversion program for juvenile offenders. First, the relationship of the nonprofessionals' personality traits and general attitudes to client outcome was examined. No statistically significant correlations were observed. Second, the differential impact of various training and supervision factors was examined in terms of nonprofessional satisfaction, attitudes, and locus of control. Results suggested that training intensity, training content, and supervision setting may influence nonprofessionals' attitudes towards various social groups and their satisfaction with the nonprofessional experience.  相似文献   
100.
Since both speech and color have perceptual ramifications in language, the present study was developed to study speech perception through color perception. With the recent advances in perception generally and color perception specifically, this nontraditional approach to studying speech perception appeared reasonable. The 12 consonants utilized in this study generated 144 pairs of nonsense CV-syllables. The consonant ensemble was selected because it accommodated a maximum number of phonological features with a minimum number of phonemes. The 46 subjects, who were in junior high school with an age range of 11 through 14 years, responded to each of the stimulus pairs by assigning (associating) to it one of the six primary colors. Because of the perceptual orderliness associated with subjects' judgments, the results indicated that color can be used to study speech perception. Specific findings included the retrieval of sameness, fronting (or place), and voicing.This study is based on a master's thesis presented to the Graduate School, Tennessee State University in Nashville. The authors gratefully acknowledge the cooperation and assistance of the Speech and Hearing Institute at the University of Texas Health Science Center-Houston.  相似文献   
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