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261.
Frederick V. Malmstrom Robert J. Randle John S. Bendix Robert J. Weber 《Attention, perception & psychophysics》1980,28(5):440-448
Concurrent mental activity seems to be a significant, nonvisual factor affecting the human accommodation response. Two experiments were conducted to determine the direction and magnitude of this accommodation response. Experiment 1 employed a concurrent, written backwards counting task. Experiment 2 employed a concurrent, mental imagery task of “thinking near” and “thinking far.” In both experiments, the concurrent secondary task effected a cumulative accommodative shift toward the visual far point of from .25 to .75 diopter away from a near (3.0 diopter) target. This accommodative shift was observed only in the presence of a stimulus field and not in open-loop (analogous to empty-field) conditions. In addition, a long-term instability in the open-loop method of obtaining the dark focus was observed. Similarities between this accommodative shift and the pupillary response are noted. The accommodation response is discussed in relationship to both an attention-sharing and an involuntary autonomic response model. 相似文献
262.
The experimental analysis of behavior has grown enormously in Latin America within the last decade. This paper offers an updating revision of suggested Spanish translations of operant expressions. 相似文献
263.
This research was concerned with the effects of different classes of cues on the ability of toads (Bufo marinus) to learn an escape task, discrimination learning, in a T-maze. The cues were either a black or white brightness cue, a right or left position cue, or combinations of brightness and position cues. The toads were given a .6-A shock until they made the correct response. Results suggested that toads are capable of learning a discrimination task based on either a position or brightness cue. However, the rate of learning was influenced by strong aversion to the white arm when escaping from an aversive stimulus. No particular preference for either brightness or position cues was found independent of this aversion. 相似文献
264.
In the first of two selective masking experiments, 7-letter rows were followed at several ISIs by a mask or no-mask and a bar-marker partial report cue. The results suggest that the arrays were processed ends-first and then, in general, from both ends towards the middle. In the second experiment, bar-marker partial report cues were presented at the onset or offset of 6-letter/1-digit or 7-letter rows. The subjects could not anticipate the category of the to-be-reported item with the alphanumeric displays. With a delayed cue, selective masking was obtained with both mixed category and pure letter arrays, but with simultaneous cuing, masking was always distributed across all serial positions. The results suggest that the subjects: (a) abstracted some information about category from the mixed arrays during an initial parallel stage of processing, (b) selectively attended to mainly the cued item with simultaneous probes with homeogeneous and mixed category displays, and (c) employed an ends-first processing strategy with both types of arrays when the bar-marker partial report cue was delayed. 相似文献
265.
N.H Azrin R.A Philip P Thienes-Hontos V.A Besalel 《Journal of Vocational Behavior》1981,18(3):253-254
A follow-up was made of the welfare payments received by AFDC clients who had received job-finding counseling. At the 6th-month follow-up, welfare payments had been reduced by about one-half for the Job Club clients vs 15% for the control group. 相似文献
266.
267.
This paper presents an empirical study of sex differences and sex-role stereotyping in clinical psychologists' reports. The results of numerous analyses showed no significant evidence at any point of sex differences or sex-role stereotyping in the form or the subject matter of the clinical reports.
相似文献268.
V Di Lollo E Woods 《Journal of experimental psychology. Human perception and performance》1981,7(4):754-769
Five experiments examined the relationship between range of spatial frequencies contained in a visual display and duration of visible persistence. The high spatial frequency contents of the display were reduced by defocusing the image at the retina. Duration of visible persistence was measured by a task that required perceptual integration of a pattern whose parts were displayed sequentially in time. Experiments 1 and 2 showed that progressive reductions in the high-frequency contents of the display produced corresponding decrements in the duration of visible persistence. Experiments 3, 4, 5 showed that decrements in the duration of visible persistence could not be attributed to changes in the apparent size or in the brightness of the display brought about by defocusing. The results were interpreted in terms of the temporal response properties of perceptual mechanisms attuned to separate ranges of spatial frequencies. Strong parallels were drawn with the multichannel theory of visual information processing proposed by Breitmeyer and Ganz. 相似文献
269.
Cerebral laterality was examined for third-, fourth-, and fifth-grade deaf and hearing subjects. The experimental task involved the processing of word and picture stimuli presented singly to the right and left visual hemifields. The analyses indicated the deaf children were faster than the hearing children in overall processing efficiency, and that they performed differently in regard to hemispheric lateralization. The deaf children processed the stimuli more efficiently in the right hemisphere, while the hearing children demonstrated a left-hemisphere proficiency. This finding is discussed in terms of the hypothesis that cerebral lateralization is influenced by auditory processing. 相似文献
270.
An evaluation is offered of one of the Government's measures to alleviate youth unemployment-the Work Experience Programme (WEP). In a small-scale study conducted in Essex, most of the young people and employers involved in the scheme thought that its benefits considerably outweighed its disadvantages, and this view was shared by careers officers. The scheme helped the young participants to develop confidence in themselves and in their working potential, although at the same time it made them anxious about their ability and/or opportunity to continue this development. As a short-term response to youth unemployment, WEP has considerable value. Without certain improvements, however, it is not adequate for dealing with long-term structural unemployment. 相似文献