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911.
Marked differences in detectability as a function of spatial location, a "detectability gradient," are observed when subjects are required to detect a briefly exposed target pattern of uncertain location in the presence of a number of nontarget patterns. Target detectability also is inversely related to the number of nontarget patterns which are present in this search paradigm. These previous findings provide strong evidence for a serial process in which increasing probability of error occurs during a scan of a rapidly degrading neural representation of the visual image following a brief exposure to the stimuli. It is not yet established whether this scan is attentional or perceptual in nature. The present experiments test the hypothesis of an attentional scan by presenting the target and nontarget patterns in spatially segregated groups. If the scan is attentional, then target detectability under these circumstances would be expected to exhibit the characteristic phenomenon of "group processing"--a close clustering of detection performance for targets located within a group and large differences in detectability across groups. As no evidence for group processing was observed, the results fail to support the view that the scan is attentional in nature but are fully consistent with a nonattentional scan.  相似文献   
912.
The paper develops a unified account of both deterministic and indeterministic laws of nature which inherits the merits but not the defects of the best existing accounts. As in Armstrong's account, laws are embodied in facts about universals; but not in higher‐order relations between them, and the necessity of laws is not primitive but results from their containing chances of 0 or 1. As in the Ramsey‐Lewis account, law statements would be the general axioms and theorems of the simplest deductive theory of everything; but because laws are not so defined, simplicity of statement is not a criterion of law‐hood.  相似文献   
913.
Permanent disruption of aspects of a highly learned skill such as walking force adaptations to occur to the movement. Firstly the body must determine what factors will guide the formation of the new walking pattern, and secondly that new movement pattern must be learned. Frequently the questionable assumption is made that the performance objectives of the new skill are the same as the original. This work used non-linear optimal control and multiple segment simulation to evaluate the ability of several possible objective functions to predict pathological walking patterns. These predictions were then also compared to the results from normal walking. Preliminary results indicate the performance objectives of pathological gaits may be quite different from those of normals. Some support was also provided for the existence of simultaneous multiple performance objectives in complex movements.  相似文献   
914.
Cann  Arnie  Siegfried  William D. 《Sex roles》1990,23(7-8):413-419
Research has consistently found that effective leadership is perceived as characterized by traits similar to those associated with masculine gender roles. These perceptions would appear to be at odds with extensive research indicating that effective leadership requires consideration and structuring behaviors—behaviors that seem to represent both masculine and feminine styles. In two separate studies, the correspondence between gender stereotypes and dimensions of effective leadership were assessed. Results indicate that consideration behaviors are perceived to be feminine, while structuring behaviors are perceived to be masculine. Similarly, qualities that characterize the masculine gender role are perceived to be consistent with structuring, while qualities associated with the feminine gender roles are perceived to be consistent with consideration. It is suggested that an increased awareness of the androgynous nature of effective leadership behaviors might weaken the biases in favor of male leaders.  相似文献   
915.
Recent research on the Ms. stereotype suggests a potentially important exception to the strong link between gender and managerial stereotypes observed in the 1970s. Specifically, we hypothesized that a woman who prefers “Ms.” as her title of address would be seen by perceivers of both sexes as more similar in the “requisite” traits of a successful, middle manager than would a woman who prefers a traditional title of address for herself. These hypotheses were tested by having respondents rate a “successful, middle manager” or other stimulus persons varying in titles of address, sex, and marital status. Correlational analyses of respondents' ratings of stimulus persons yielded strong support for the hypotheses. That is, a woman preferring Ms. as her title of address was seen by adult perceivers of both sexes as possessing the “requisite” personality characteristics of a successful, middle manager; whereas a traditionally titled woman was not. Implications of these findings are discussed.  相似文献   
916.
It was hypothesized that older widows (N=309) who had been care givers to their husbands would have undertaken a greater number of household responsibilities than had women who had not been care givers. Findings indicated that, prior to the husband's death, more traditionally male and more traditionally female tasks were performed by the care-giving wives (n=158). This was particularly true in the case of Alzheimer's care givers (n=21). More importantly, widows' present feelings of competence were related to undertaking household responsibilities, with those who had been care givers expressing significantly higher levels of competence.  相似文献   
917.
The relationship between program performance and outcome for patients in maximum security token economy programs has not been previously studied. We examined variables related to success in a token economy program and to postrelease failure for 92 men in a maximum security psychiatric hospital. Point earnings later in the program were best predicted by earlier point earnings. Variables that best predicted postrelease failure, defined in various ways, were similar to those found in other studies; youthfulness, having spent more time in institutions, a diagnosis of personality disorder or retardation rather than psychosis, not having been found not guilty by reason of insanity or unfit to stand trial, and having been referred from another psychiatric hospital. That program variables were generally unrelated to later outcome suggests that treatment programs for patients in maximum security settings must emphasize skills that are relevant to postrelease success.  相似文献   
918.
This experiment compared the extent to which students learned facts included in computer-based-training frames that required an overt response to those that did not. Frames included two types of facts: Some facts had one word missing which had to be supplied by the student (active facts). Other facts had no missing words and required no overt response (passive facts). Each student completed four 14-fact modules in random order. Two of the modules contained frames with all active facts. Each frame in the other two modules contained one active and six passive facts. Paper pretests and posttests showed that students learned twice as many facts when all facts in the module were active than when only one in seven were active. The modules that included passive facts required one-fifth the time to complete than those with only active facts. Students learned more facts per minute of training in one of the two modules that included passive facts than in the two modules with only active facts.  相似文献   
919.
From Dialog's PsychINFO database the number of studies with 6 species reported in the Psychological Abstracts was calculated for each year from 1967 to 1988. Also, the number of studies with an additional 11 species were calculated for each year from 1973 to 1988. A hand search in the Journal of the Experimental Analysis of Behavior and Learning and Motivation was also conducted to explore trends in studies on 12 species from 1970 to 1987. The numbers of studies on many species (e.g., baboons, bats, chimpanzees, dolphins, gerbils, guinea pigs, gorillas, hamsters, lemurs, mice, pigeons, rats, seals, and snakes) have remained stable. There has, however, been a steady decline in the numbers of studies on selected species (e.g., cats, dogs, and rabbits). Possible reasons for changing trends in studies on selected species include: increased costs, the cognitive emphasis in psychology, and arguably, animal rights activism.  相似文献   
920.
Feigned insanity in nineteenth-century America is appraised through a review of the medical and legal literature. The authors focus on the explanations for feigning, procedures used in uncovering feigning, and the role of feigning in the courtroom. This discussion of feigned insanity demonstrates the remarkable consistency of approach to this form of malingering over the past 200 years.  相似文献   
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