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831.
The effects of alcohol and extended practice on divided attention were investigated using a visual tracking task and an auditory detection task. Subjects performed the tasks with and without alcohol, under single-task (S) and dual-task (D) conditions, both before and after they had received extended practice under single-task conditions without alcohol. Tracking accuracy improved with practice and was impaired under divided-attention conditions but was not affected by alcohol. Speed of detection was impaired by alcohol, improved by practice, and impaired by divided attention. Extended practice did not reduce the influence of alcohol. The effects of both alcohol and practice on speed of detection were significantly greater under dual-task conditions than under single-task conditions. Analysis of detection-task reaction times in terms of relative divided-attention costs, (D-S)/S, showed no effect of alcohol, but a highly significant reduction in costs with extended practice. It is concluded that (1) alcohol and practice can have quantitatively, but not qualitatively, similar effects on speeded performance, and (2) the effect of alcohol is not influenced by the attentional requirements of the task. 相似文献
832.
It has recently been claimed (Geiger & Lettvin, 1987; Perry, Dember, Warm, & Sacks, 1989) that the acuity/eccentricity function is flatter in dyslexics than in normal subjects, with dyslexics showing better performance in the periphery and worse performance at fixation. In these studies, all target letters were presented to the right of fixation, a procedural flaw inviting subjects to optimize performance by directing attention and/or gaze to the right of the designated fixation point. It is suggested that dyslexic and normal readers may differ in the degree to which they might adopt the optimal strategy in this situation. To overcome this problem, target letters were briefly presented at 16 randomly intermixed locations derived from the orthogonal combination of four eccentricities and four directions from fixation (above, below, right, left). The accuracy of letter identification declined with increasing eccentricity at the same rate for good and poor adult readers and dyslexic teenagers. This finding provides no support for the view that the acuity/eccentricity function might vary with and possibly cause differences in reading level. 相似文献
833.
On the basis of a conditioning analysis of the orientation-contingent color aftereffect (McCollough effect, ME), orientation stimuli become associated with simultaneously presented chromatic stimuli. This account suggests that decreasing the contingency between the grid orientation and color should decrease the strength of the aftereffect. Results of previous research indicate that decreasing the temporal contingency (by presenting homogeneous chromatic stimuli between presentations of chromatic grids) does not decrease the ME. However, it has been suggested that the appropriate contingency-degradation procedure would involve decreasing spatial (rather than temporal) contingency. That is, the illusion should be attenuated by extending the color beyond the confines of the grid. Contrary to this hypothesis, the results of the present experiments provide no evidence that decreasing the spatial contingency between grid and color decreases the ME; rather, the aftereffect is increased by such a manipulation. 相似文献
834.
Reaction time (RT) for two three-segment target-striking responses involving changes in direction of movement was studied as a function of differences in their additive index . . . index of difficulty (A-ID). In one condition the A-ID was 9.96 and in the other, 6.76. For 16 right-handed university students, mean RT was significantly faster for the condition in which the index was 6.76. Movement times were consistent with Fitts' Law. The data support Sidaway, Christina, and Shea's 1988 prediction that for target-striking movements with changes of direction, RT is a function of the cumulative series of movement constraints. 相似文献
835.
A TEST OF THE SITUATIONAL LEADERSHIP THEORY 总被引:2,自引:0,他引:2
836.
NORMAN G. PETERSON LEAETTA M. HOUGH MARVIN D. DUNNETTE RODNEY L. ROSSE JAMS S. HOUSTON JODY L. TOQUAM HILDA WING 《Personnel Psychology》1990,43(2):247-276
A major goal of the Army Selection and Classification Project was to develop an experimental predictor battery that would best supplement the Armed Forces Vocational Aptitude Battery for making selection and classification decisions for entry-level enlisted personnel. That is, what predictor measures would best serve the needs of all the jobs in an entire selection/classification system? This paper describes the characteristics of the new test battery and the procedures that were used to develop it. The major steps in the procedure were a structured literature search using a standard protocol, an extensive expert judgment study of expected true validities for a population of predictor variables against a population of performance components, fabrication of modularized software and a special response pedestal for computerized measurement of perceptual and psychomotor abilities, evaluations of experimental measures in three iterative pilot tests and one major field test, and a series of reviews by a panel of scientific advisers. The test battery that resulted from this 2 1/2-year development effort is described. The basic psychometric properties of each measure, as determined in a large concurrent validation sample, are also described. 相似文献
837.
Biotinidase deficiency is the primary biochemical defect in late-onset multiple carboxylase deficiency and an autosomal recessive disorder and characterized by seizures, ataxia, alopecia and skin rash. We describe a colorimetric semiquantitative method for screening for biotinidase activity from dried samples of whole blood spotted on filter papers. The administration of biotin to affected children can be a lifesaving procedure and can prevent irreversible neurologic damage. 相似文献
838.
G Huber 《Psychiatrie, Neurologie, und medizinische Psychologie》1990,42(1):11-24
The question if there are "symptomatic schizophrenias" has been discussed since the 20s. Schizophrenic psychoses caused be definable and well known brain diseases are presented. All schizophrenic symptoms and syndromes, the first rank symptoms (K. Schneider) too, occur in somatically founded psychoses. The group of paroxysmal transition syndromes in the sense of aura prolongata (continua) and the episodic schizophrenic psychoses in psychomotor epilepsy may be a model for the schizophrenia research. Vital threatening, so-called pernicious catatonic schizophrenias are found on the basis of infectious brain diseases, sometimes only diagnosed in autopsy. Beside acute and reversible symptomatic schizophrenic psychoses there are, even if rarely, recurrent and chronic courses of symptomatic schizophrenias. That certain conditions for the developing of symptomatic schizophrenias are rarely realised, could be an explanation for their rarity. Some findings indicate that the limbic system is significant for symptomatic (and idiopathic) schizophrenic psychoses and the pre- and postpsychotic basic stages determined by dynamic and cognitive basic symptoms, which are phenomenologically very similar to aura symptoms released by stereoelectroencephalographic depth recordings (Wieser). The characteristic features of marked fluctuation, discontinuity and insteadiness of the cognitive thought, perception, psychomotor and cenesthetic phenomena do not speak against an organic brain disorder provided that the traditional process hypothesis is abandoned in favor of a neurobiochemic disorder, fluctuating on its part depending on endogenous as well as psychic-reactive factors. 相似文献
839.
Today historiography (the writing of stories) presented as nothing but a search for truth merits the charge of naiveté. Since Freud we must understand any story told about life as a rationalization, that is, as a strategy of conducting one's life. The author argues the proposition that historiography can only fulfill its function of giving sense to life if it simultaneously admits its deconstruction, its counter-sense. 相似文献
840.
G Mladek M L?ffler P Nickel 《Psychiatrie, Neurologie, und medizinische Psychologie》1990,42(6):356-363
In forensic psychology, recommendations that courts request when granting one of the parents the right of child upbringing after a divorce pose a problem for the person who is required to give such expert judgment. The authors describe the difficult situation he faces when having to decide for and, at the same time, against one of the parents. A good knowledge of family psychology and pathopsychology is essential, and for drawing up the expertise and stating his reasons, the expert requires methodical resources. The authors describe four procedures of relational diagnosis and recommend the combined use of these in conjunction with methods that have been employed so far. 相似文献