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901.
Since the 1970s, investigative profilers at the FBI's Behavioral Science Unit (now part of the National Center for the Analysis of Violent Crime) have been assisting local, state, and federal agencies in narrowing investigations by providing criminal personality profiles. An attempt is now being made to describe this criminal-profile-generating process. A series of five overlapping stages lead to the sixth stage, or the goal of apprehension of the offender: (1) profiling inputs, (2) decision-process models, (3) crime assessment, (4) the criminal profile, (5) investigation, and (6) apprehension. Two key feedback filters in the process are: (a) achieving congruence with the evidence, with decision models, and with investigation recommendations, and (b) the addition of new evidence.  相似文献   
902.
This paper reviews the literature on scapegoating, elaborating on the underlying mechanisms before describing the process of scapegoating as it occurred in a neonatal nurse support group. Illustrative vignettes are used to discuss how scapegoating was used by group members to avoid painful feelings arising from their care of extremely ill infants. Group process is related to the stages of the group's development as feelings were addressed more directly and the need to use scapegoating as a defense decreased.  相似文献   
903.
A study is reported which shows that accommodation can be stimulated by a blur stimulus which is below the threshold for visual perception. It is also shown that perceptual fading of the target, caused by stabilization of the retinal image (Troxler phenomenon), can eliminate the accommodative response causing it to default to its resting level. The first finding suggests a way in which the visual system can filter the percept of blur out of our conscious awareness and still effectively utilize the blur as a steady-state error for the accommodative control system. The second finding is consistent with a locus for the Troxler phenomenon in the early afferent part of the visual pathway, ie the retinal ganglion cells.  相似文献   
904.
Adaptation and reaction-time techniques were used to examine the role of different spatial-frequency channels in the perception of local and global structure. Subjects were shown figures consisting of a large C composed of smaller Cs and asked to identify the orientation of either the global C or its local elements. Prior to performing the task subjects were adapted to different spatial frequencies and the effect on subsequent performance was assessed. Two main results were found. First, the adapting frequency that most affected the global task was often lower than that most affecting the local task, suggesting that high and low frequencies independently code the structure of an image. Second, reaction time to global figures was often faster than to local figures at all levels of detectability, again suggesting a role of low-frequency channels in global processing.  相似文献   
905.
Static depiction of movement   总被引:1,自引:0,他引:1  
A number of pictorial devices were compared in order to assess their relative effectiveness in depicting events. Effectiveness, as measured by a rating task, did not seem to be a function of the classification of a device as natural or metaphorical. Rather, it depended on whether a given device highlighted a distinctive aspect of a particular event (running, jumping, or moving), or simply modified the event. This observation was buttressed by the existence in a forced-choice task of a category boundary for depictions of running (pictures with a certain device were seen as running, those without it were not) but not for moving or jumping. Even preschool children displayed some understanding of metaphorical devices. They chose figures with those devices as running faster than the experimental standard. Results are discussed in the context of Kennedy's characterization of pictorial metaphors and Gibson's framework for understanding the relationship between pictorial and environmental information.  相似文献   
906.
E K Warrington  M James 《Perception》1986,15(3):355-366
An investigation is reported of the ability of normal subjects and patients with right-hemisphere lesions to identify 3-D shadow images of common objects from different viewpoints. Object recognition thresholds were measured in terms of angle of rotation (through the horizontal or vertical axis) required for correct identification. Effects of axial rotation were very variable and no evidence was found of a typical recognition threshold function relating angle of view to object identification. Although the right-hemisphere-lesion group was consistently and significantly worse than the control group, no qualitative differences between the groups were observed. The findings are discussed in relation to Marr's theory that the geometry of a 3-D shape is derived from axial information, and it is argued that the data reported are more consistent with a distinctive-features model of object recognition.  相似文献   
907.
Earlier studies have shown the girls spend more time than boys in activities that are highly structured by adults. Structured activities may encourage feminine sex-typed behaviors such as compliance to adults; low-structure activities may encourage masculine sex-typed behaviors such as independence and assertiveness. In the present study the effects of high or low levels of adult structuring on children's social behavior during preschool free-play activities were tested in a field experiment carried out during an entire semester in one preschool classroom. For the first 15 minutes of free play, children were assigned to high- or low-structure activities. As predicted, when children were in high-structure activities, they exhibited high rates of bids for recognition and compliance to adults; in low-structure activities, they exhibited peer-directed leadership, bids for recognition, and compliance. There were no generalized effects of these treatments on their subsequent free choice of activities or social behavior. The study demonstrates powerful effects of naturally occurring variations in children's play activities on sex-typed social behaviors.  相似文献   
908.
Summary Subjects were shown eight-letter pseudowords tachistoscopically and were asked to report as many letters as possible. The pseudowords, examples of either first- or fourth-order approximation to English, were printed in normal or reversed spelling and were presented in either normal of mirror-imaged letters. Finally subjects were either free to report in any order they wished, or they were instructed to report from left to right or from right to left. With normal letters, the familiarity effect was controlled by the spelling direction, not by the direction of report or the match between direction of report and spelling direction. With mirrored letters, however, order of approximation to English had no effect. The results contradict two existing theories: Mewhort's theory claims that the familiarity of fourth-order materials aids processing at a postcategorical level; it has trouble explaining why the familiarity effect disappeared with mirrored letters and normal spelling. Wolff's theory claims that familiarity aids processing at the feature level; it has trouble explaining why the familiarity effect disappeared with mirrored letters and reversed spelling.  相似文献   
909.
910.
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