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931.
In the aftermath of several school shooting incidents in recent years, students’ perceptions of unsafe schools has been a
major concern for parents, teachers, school officials, school practitioners, and policy-makers. Using Bronfenbrenner’s ecological
systems framework, we examined the micro-, meso-, and exosystem level factors associated with perceptions of unsafe school
environments in a nationally representative sample of 10- to 15-year-old youth in the United States. We found that for the
socio-demographic characteristics, students who were older, male, and poor had increased risks of perceiving higher levels
of unsafe school environments. Within the microsystem of the family, our results indicate that parent-youth discussions of
school activities/events decreased the risk of students perceiving unsafe schools. All of the school environment variables—ease
of making friends, teachers’ involvement, observed weapon carrying, and school rule enforcement—were related in the expected
direction to students’ perceiving their schools as unsafe. At the mesosystem level, findings from our study demonstrate that
variables measuring parental school involvement were unrelated to perceptions of school safety. Finally, at the exosystem
level, we found that students’ perceptions of residing in a safer neighborhood and residence in a non-central city metropolitan
area, compared with a central city, decreased the odds of perceiving school environments as unsafe. School policy and practice
implications are discussed. 相似文献
932.
933.
In the present study, introductory-level German students read a simplified story and learned the meanings of new German words
by reading English translations in marginal glosses versus trying to infer (i.e., guess) their translations. Students who
inferred translations were given feedback in English or in German, or no feedback at all. Although immediate retention of
new vocabulary was better for students who used marginal glosses, students who inferred word meanings and then received English
feedback forgot fewer translations over time. Plausible but inaccurate inferences (i.e., those that made sense in the context)
were more likely to be corrected by students who received English feedback as compared with German feedback, providing support
for the beneficial effects of mediating information. Implausible inaccurate inferences, however, were more likely to be corrected
on the delayed vocabulary test by students who received German feedback as compared with English feedback, possibly because
of the additional contextual support provided by German feedback. 相似文献
934.
A positive relationship between prior knowledge and item memory is a consistent finding in the literature. In the present
study, we sought to determine whether this relationship extends to episodic details that are present at the time of encoding,
namely source memory. Using a novel experimental design, we were able to show both between- and within-subjects effects of
prior knowledge on source memory. Specifically, the results revealed that the degree of prior knowledge positively predicted
memory for source specifying contextual details. In addition, by including two conditions in which attention was divided either
at encoding or retrieval, we were able to show that prior knowledge influences memory by affecting encoding processes. Overall,
the data suggest that a priori knowledge within a specific domain allows attentional resources to be allocated toward the
encoding of contextual details. 相似文献
935.
The type of experience involved with an object category has been regarded as one important factor in shaping of the human
object recognition system. Laboratory training studies have shown that different kinds of learning experience with the same
set of novel objects resulted in different perceptual and neural changes. Whether this applies to natural real-world objects
remains to be seen. We compared two groups of observers who had different learning experiences with faces, using holistic
processing as a dependent measure. We found that, while ordinary observers had extensive individuation experience with faces
and displayed typical holistic face processing, art students who had acquired additional experience in drawing faces, and
thus in attending to parts of a face, showed less holistic processing than did ordinary observers. These results converge
with laboratory training studies on the role of type of experience in the development of different perceptual markers for
different object categories. It is thus insufficient to categorize expertise simply in terms of object domains (e.g., expertise
with faces). Instead, perceptual expertise should be classified in terms of the underlying process or task demand. 相似文献
936.
Ageism has resulted in overstated expectations regarding the inevitable deterioration in human capabilities, such as visual perception, with age (Rowe and Kahn in Science, 237, 143?C149, 1987; Grant in Health and Social Work, 21, 9?C15, 1996). Human visual perception, however, is of a largely constructive nature, evidenced in the complementary interactions between top-down inputs (e.g., expectations) and bottom-up stimuli (Engel et al. in National Review of Neuroscience, 2(10), 704?C716, 2001; Miller and Cohen in, Annual Review of Neuroscience, 24, 167-202, 2001). Based on this constructive nature, we hypothesized that visual perception may be better than is typically expected. In three experiments, we demonstrated the malleability of visual acuity using a conditioning procedure involving manipulations in bottom-up stimuli. Experimental groups read a book excerpt with one letter in decreased font size, while the control groups read the same book excerpt with all letters in the same font size. Experiment 1 (N?=?112) examined whether visual acuity could be enhanced for a specific letter. Experiment 2 (N?=?70) assessed whether visual acuity could be enhanced for a non-conditioned letter, while Experiment 3 (N?=?108) evaluated whether the visual conditioning effects would transfer to all non-conditioned letters. Visual acuity for experimental groups was significantly better than that in the control groups, speaking to the general malleability of our visual sense. 相似文献
937.
We investigated the use of space in the comprehension of the concept of quantity in text. Previous work has suggested that the right-left axis is useful in spatial representations of number and quantity, while linguistic evidence points toward use of the up-down axis. In Experiment 1, participants read sentences containing quantity information and pressed buttons in either (1) an up and a down position or (2) a left and a right position. In Experiment 2, the participants pressed buttons in either (1) up and down positions or (2) left and right positions, but heard the sentences rather than reading them. We found spatial compatibility effects for the up-down axis, but not for the right-left axis. Additionally, the spatial compatibility effect was observed whether or not the participants moved to make their responses. We discussed the results in the context of embodied approaches to the comprehension of quantity information. 相似文献
938.
We are constantly exposed to our own face and voice, and we identify our own faces and voices as familiar. However, the influence
of self-identity upon self-speech perception is still uncertain. Speech perception is a synthesis of both auditory and visual
inputs; although we hear our own voice when we speak, we rarely see the dynamic movements of our own face. If visual speech
and identity are processed independently, no processing advantage would obtain in viewing one’s own highly familiar face.
In the present experiment, the relative contributions of facial and vocal inputs to speech perception were evaluated with
an audiovisual illusion. Our results indicate that auditory self-speech conveys a processing advantage, whereas visual self-speech
does not. The data thereby support a model of visual speech as dynamic movement processed separately from speaker recognition. 相似文献
939.
Pratt, Adam, and Fischer (2007) investigated the effect of surrounding targets on the time it took to move to an individual target and found that the movement
time to a central target was above the Fitts’s law line related to the first and last targets. They explained their results
in terms of a “visuomotor hypothesis.” Here, an alternative explanation is given in terms of a previously validated model
of the “available target width” that is determined by the size of the target and the width of the finger pad that is being
used to hit the target. 相似文献
940.
Using two clinical samples of patients, the presented studies examined the construct validity of the recently revised Anxiety Sensitivity Index-3 (ASI-3). Confirmatory factor analyses established a clear three-factor structure that corresponds to the postulated subdivision of the construct into correlated somatic, social, and cognitive components. Participants with different primary clinical diagnoses differed from each other on the ASI-3 subscales in theoretically meaningful ways. Specifically, the ASI-3 successfully discriminated patients with anxiety disorders from patients with nonanxiety disorders. Moreover, patients with panic disorder or agoraphobia manifested more somatic concerns than patients with other anxiety disorders and patients with nonanxiety disorders. Finally, correlations of the ASI-3 scales with other measures of clinical symptoms and negative affect substantiated convergent and discriminant validity. Substantial positive correlations were found between the ASI-3 Somatic Concerns and body vigilance, between Social Concerns and fear of negative evaluation and socially inhibited behavior, and between Cognitive Concerns and depression symptoms, anxiety, fear of negative evaluation, and subjective complaints. Moreover, Social Concerns correlated negatively with dominant and intrusive behavior. Results are discussed with respect to the contribution of the ASI-3 to the assessment of anxiety-related disorders. 相似文献