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261.
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
262.
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
263.
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
264.
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
265.
People can learn word–referent pairs over a short series of individually ambiguous situations containing multiple words and
referents (Yu & Smith, 2007, Cognition 106: 1558–1568). Cross-situational statistical learning relies on the repeated co-occurrence of words with their
intended referents, but simple co-occurrence counts cannot explain the findings. Mutual exclusivity (ME: an assumption of
one-to-one mappings) can reduce ambiguity by leveraging prior experience to restrict the number of word–referent pairings
considered but can also block learning of non-one-to-one mappings. The present study first trained learners on one-to-one
mappings with varying numbers of repetitions. In late training, a new set of word–referent pairs were introduced alongside
pretrained pairs; each pretrained pair consistently appeared with a new pair. Results indicate that (1) learners quickly infer
new pairs in late training on the basis of their knowledge of pretrained pairs, exhibiting ME; and (2) learners also adaptively
relax the ME bias and learn two-to-two mappings involving both pretrained and new words and objects. We present an associative
model that accounts for both results using competing familiarity and uncertainty biases. 相似文献
266.
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
267.
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
268.
Ecological valence theory (EVT; Palmer & Schloss, Proceedings of the National Academy of Sciences 107:8877–8882, 2010) proposes that color preferences are due to affective responses to color-associated objects: That is, people generally like
colors to the degree that they like the objects associated with those colors. Palmer and Schloss found that the average valence
of objects associated with a color, when weighted by how well the objects matched the color (weighted affective valence estimates:
WAVE) explained 80% of the variation in preference across colors. Here, we replicated and extended Palmer and Schloss’s investigation
to establish whether color–object associations can account for sex differences in color preference and whether the relationship
between associated objects and color preference is equally strong for males and females. We found some degree of sex specificity
to the WAVEs, but the relationship between WAVE and color preference was significantly stronger for males than for females
(74% shared variance for males, 45% for females). Furthermore, analyses identified a significant inverse relationship between
the number of objects associated with a color and preference for the color. Participants generally liked colors associated
with few objects and disliked colors associated with many objects. For the sample overall and for females alone, this association
was not significantly weaker than the association of the WAVE and preference. The success of the WAVE at capturing color preference
was partly due to the relationship between the number of associated objects and color preference. The findings identify constraints
of EVT in its current form, but they also provide general support for the link between color preference and color–object associations. 相似文献
269.
The objective of the study is to assess views of age related changes in sexual behavior among married Thai adults age 53–57.
Results are viewed in the context of life course theory. In-depth interviews were conducted with 44 Thai adults in Bangkok
and the four regions of Thailand. Topics covered include changing sexual behavior with age, adjustment to this change, gender
differences in behavior, attitudes toward commercial sex and other non-marital sexual partners, and condom use. Most respondents
were aware of this change and saw a decrease in sexual activity and desire more often among women compared to men. At the
same time, many respondents viewed sexuality as important to a marriage. Some respondents accepted the decrease in sexual
activity and focused more on work, family and temple activities. Thai Buddhism was seen as an important resource for people
who were dealing with changes due to aging. Other persons turned to other partners including both commercial and non-commercial
partners. The influence of the HIV epidemic that began in the 1990s was seen in concerns about disease transmission with extramarital
partners and consequent attitudes toward condom use. The acceptability of extramarital partners in the family and community
ranged from acceptance to strong disapproval of extramarital relationships. 相似文献
270.
The recent trend in the feminization of the HIV epidemic poses great risk to women, especially to the wives of men who have
sex with men (MSM). The objective of the present study was to explore wives’ responses to their husbands’ sexual orientation
as well as the factors that influence their sexual health in India. For this research, 15 wives who were aware of their husbands’
sexual orientation and their husbands were interviewed separately using semi-structured in-depth interviews and focus groups.
The study explored the social and cultural structures that create gender inequality, which put women married to MSM at sexual
health risk. These factors need to be addressed carefully through existing MSM targeted interventions, without breaching the
confidentiality of either partner. 相似文献