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251.
This experiment assessed the proposal that performance differences associated with field independence/field articulation reflect differential efficiency in the use of a limited capacity information-processing system termed working memory. Extreme scores on a group-administered version of the embedded figures test were used to identify subjects “high” and “low” in degree of field articulation. The task required that a subject retain a series of digits for subsequent report while performing a semantic modification of a target phrase. Concurrent information load on working memory was varied in two ways: by increasing memory load from 3 to 6 digits, and by increasing the complexity of the semantic processing required. In low information load conditions no differences were found between high FA and low FA groups. In high information load conditions low FA subjects made more errors in digit recall and took longer to perform the difficult semantic modification.  相似文献   
252.
Principal-components analysis was performed on a set of averaged evoked potentials in order to extract components of cerebral activity functionally related to hemisphere, handedness, processing task, and stimulus feature variables. Eight such components were isolated. Degree of dextrality, hemispheric differences, and cognitive operations in processing distinct stimulus characteristics were identified as reflected in functionally distinct components of brain activity.  相似文献   
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254.
The present experiments examined the role of imagery ability in recall of either the terminal location or the distance of a preselected horizontal linear movement following changes in the recall starting position. Subjects were selected on the basis of their scores on a shortened version of the Betts Questionnaire upon Mental Imagery (Betts Q.M.I., Sheehan 1967). Both high and low imagers were assigned to one of four groups, HIL, LIL, HID, LID, the last letter indicating the movement cue (terminal location or distance moved) to be recalled. Recall of the appropriate movement cue from one of four new recall starting positions occurred after either a 5-sec or 30-sec unfilled retention interval. Analysis of constant error indicated all groups were unable to recall the specified movement cue independent of the other source of information, even when subjects were given explicit instructions to utilise an imagery strategy. The data corroborate our earlier findings that memory for self paced movements is based on an interaction of location and distance cues derived from the criterion movement.  相似文献   
255.
Investigated were differences in paired-associate learning for auditory versus visual modalities and within each modality the anticipation and study test methods of item presentation were compared. Extant reports re these two sensory modalities and of the two learning methods had been inconsistent. In this study of 40 university students, the learning of CVC-CVC nonsense syllable pairs was significantly better with the visual than with the auditory modality. The study-test method was significantly superior to the anticipation method in the visual mode. With auditory presentations, however, acquisition levels for both methods were the same. Significant interactions were observed between sensory modalities and methods of presentation. At present the retention interval theory (Izawa 1972–1979b) appears to account best for the varied findings with respect to the two methods of presentation.  相似文献   
256.
Slow brain potentials were recorded during the foreperiod of a reaction time task, and the effects of instructions governing the trade-off between speed and accuracy were investigated. One brain potential, a slow negative shift preceding S2, was largely attenuated under accuracy instructions. It is suggested that this shift is dependent on a motor response and that its amplitude reflects the level of motor preparation. Two other brain potentials, a slow positive and a slow negative wave, seem to depend on the psychological properties of S1. Enhanced amplitudes were found, when S1 provides information, besides its warning function.  相似文献   
257.
The effect of sorrounding context on the recognition of objects from briefly presented pictures was investigated. Forty-eight undergraduates saw 100 msec displays of either line drawings containing several objects embedded in context or drawings of object arrays without background context. Following each exposure they were required to select from among four objects the one that had been contained in the picture. Presentation of objects in context aided recognition only when incorrect response alternatives were inconsistent with the picture context. The results suggest that context contributes to the construction of a general characterization of the pictures which provides expectancies regarding the identity of specific objects.  相似文献   
258.
259.
Twenty-five people who had made voluntary, radical occupational changes in mid-career were interviewed and compared and contrasted with people remaining in matched occupations. Four categories of factors emerged from the data as being important to mid-career occupational change: factors associated with the first occupation, factors associated with the second occupation, obstacles to change, and personal factors. Dissatisfaction with the first occupation and attraction to a second occupation are both necessary for change to occur but do not in all cases cause change. Dissatisfaction results from a lack of congruence between a person's work orientations and the rewards of an occupation, and attraction results from a perceived congruence between the two. Obstacles to change are most financial in nature and can deter or delay change even when dissatisfaction and attraction exist. Differing personal beliefs about the control one has over one's life and one's ability to succeed in new areas in large part determine whether obstacles deter change or not.  相似文献   
260.
This study purports to test a theory of life and career stages developed by Daniel Levinson and his associates. The theory suggests four distinct stages between ages 20 and 45 each with their own developmental tasks and related behaviors and attitudes. Subjects (759 managerial, professional, and technical employees) were selected randomly from levels and departments of a major public sector employer in the midwest United States. The measure of career stage asked respondents to indicate whether they had passed through, were still in, or had not yet reached each stage as operationalized by a short vignette. Attitudinal and behavioral measures were abstracted from previously developed instruments. Only moderate support for the theory was found with little or no evidence to support the age-linked notion of these stages. Stages were found to be discriminable in terms of certain attitudes (upward mobility, career and overall job satisfaction, and job commitment) as predicted. Suggestions are given for improvements in measurement, research design, and theory refinement.  相似文献   
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