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431.
In the United States, reported child abuse rates vary dramatically with race. We employed a scenario methodology to examine whether teachers, whose professional obligations include reporting suspected instances of abuse, exhibit bias in evaluating a possibly abused child. Each teacher (180 White, 180 Black, and 180 Hispanic) read one of six profiles about a hypothetical elementary school student and then expressed extent of agreement with either a statement that the child is being physically abused or a statement that the child should be reported as being physically abused. Within the set of profiles, race of the child and severity of abuse were manipulated. When the child in the profile was severely abused, responses for the two judgmental tasks were comparable. However, when the child was moderately abused, teachers asked whether the child was abused gave higher responses than their counterparts who were asked whether the child should be reported. No effects of race of the child or race of the teacher were observed. 相似文献
432.
Despite that fact that landmarks play a prominent role in human navigation, experimental evidence on how landmarks are selected and defined by human navigators remains elusive. Indeed, the concept of a ‘landmark’ is itself not entirely clear. In everyday language, the term landmark refers to salient, distinguishable, and usually nameable objects, rendering the problem of landmark recognition a special case of the general object recognition problem. In contrast, in the insect and robot literature, this notion of landmarks is often replaced by the “local position information” [e.g., Trullier, O., Wiener, S., Berthoz, A., &; Meyer, J.-A. (1997). Biologically based artificial navigation systems: Review and prospects. Progress in Neurobiology, 51, 483–544], referring to the entire set of sensor readings obtained at one location. This set may then serve as a characteristic of the particular location. Honey bees have been shown to base place recognition and homing on a snapshot-like memory of the place’s visual environment, not on the distances to recognized objects [Cartwright, B., &; Collett, T. (1983). Landmark learning in bees. Experiments and models. Journal of Comparative Physiology A, 151, 521–543]. A number of theoretical models of snapshot-based homing [e.g., Franz, M., Schölkopf, B., Mallot, H. A., Bülthoff, H. H. (1998). Where did I take that snapshot? Scene-based homing by image matching. Biological Cybernetics, 79, 191–202; Vardy, A., &; Möller, R. (2005). Biologically plausible visual homing methods based on optical flow techniques. Connection Science, 17, 47–89] predict that the accuracy of snapshot-based homing should depend on image contrast. For rodent hippocampal place fields, models have been developed using additional image information such as three-dimensional depth and allocentric orientations (e.g., room axes) and are thus less sensitive to image contrast and noise [e.g. Barry, C., Lever, C., Hayman, R., Hartley, T., Burton, S., O’Keefe, J., et al. (2006). The boundary vector cell model of place cell firing and spatial memory. Reviews in the Neurosciences, 17, 71–79]. Here, we study human visual homing in a virtual environment void of objects and readily detected image features. The environment was a circular room with a homogenous colour gradient covering the wall and uniform floor and ceiling. Subjects were able to approach remembered places. Accuracy decreased with colour gradient modulation and room size, in qualitative agreement with the snapshot model but not with other models of place recognition. We conclude that human memory for places can make use of a snapshot algorithm. 相似文献
433.
434.
Samantha R. Russo Jennifer Croner Samantha Smith Meaghan Chirinos Mary Jane Weiss 《Behavioral Interventions》2019,34(4):495-503
Individuals with autism and/or developmental disabilities are more likely than their typically developing peers to be food selective. Evidence‐based treatment packages for food refusal and selectivity include the use of reinforcement, escape extinction, and manipulation of antecedent events . In the current study, the variety of foods consumed by two adolescent males with food selectivity were systematically increased to include a variety of foods across all of the food groups. A changing criterion design was used to systematically increase the expectation of the amount and variety of foods that were consumed. 相似文献
435.
We examined how the format in which uncertainty information is presented affects two biases in humans' choice behavior. In a computer task, participants were given four common-ratio effect and four common-consequence effect problems in each of four different formats. In these problems, uncertainty information was described, as percentages (e.g., 80%) or as frequencies (e.g., 16/20), or was experienced, either serially (20 outcomes shown one at a time) or simultaneously (20 outcomes all shown at once). Presenting information as percentages attenuated the common-ratio effect and augmented the common-consequence effect, which suggests that these biases have different underlying mechanisms. Participants' percentage estimates of outcome likelihoods did not differ according to the format in which the information was presented; however, participants' nonverbal estimates of outcome likelihoods differed across formats. The results suggest that uncertainty information presented as percentages is processed differently than the same uncertainty information presented in other formats. 相似文献
436.
The risk of tobacco use during adolescence may be traced back to early childhood, the time when a child is most vulnerable
to environmental influence. We examined daily-life enrichment during pre-kindergarten period as a predictor of initiation
of cigarette smoking among Asian American and Hispanic/Latino children during adolescence. Survey data were collected from
students in grades seven to nine in California. Among the 2,719 participants who completed the survey, 37% were Asian American
and 44% were Hispanic/Latino. Five aspects of childhood life before kindergarten were assessed, including having lots of toys
for the child, parents' read to the child often, having a plenty of good food for the child, bringing the child to travel,
and parents spending adequate time with the child. Findings from our research indicate that children with more enriched early
childhood are less likely to start smoking during adolescence. Consequently, enhancing daily life during early childhood may
represent a new strategy for adolescent smoking prevention. 相似文献
437.
Spider-phobic and nonphobic subjects searched for a feared/fear-relevant (spider) or neutral target (mushroom) presented in visual matrices of neutral objects (flowers). In half of the displays, the mushroom target was paired with a spider distractor, or a spider target was paired with a mushroom distractor. Although all subjects responded faster to the neutral target than to the feared/fear-relevant target, phobics were slower to respond than nonphobics when a mushroom target was presented with a spider distractor. Their eyes appeared to be drawn to the feared distractor before fixating neutral targets. A further experiment indicated no group differences when subjects merely judged the homogeneity of matrices. Thus, threat seems to capture the attention of phobics only when it is part of a background that subjects are explicitly instructed to ignore. 相似文献
438.
439.
Eight hundred employees from across the U.S. work force participated in a detailed 13-month longitudinal study of involvement in learning and development activities. A new model was posited and tested in which the hypothesized sequence was as follows: worker age --> individual and situational antecedents --> perceived benefits of participation and self-efficacy for development --> attitudes toward development --> intentions to participate --> participation. The results depict a person who is oriented toward employee development as having participated in development activities before, perceiving themselves as possessing qualities needed for learning, having social support for development at work and outside of work, being job involved, having insight into his or her career, and believing in the need for development, in his or her ability to develop skills and to receive intrinsic benefits from participating. Given the aging work force, a detailed treatment of age differences in development is presented. Implications for new ideas in practice and future research are discussed. 相似文献
440.
Weiss SJ Kearns DN Cohn SI Schindler CW Panlilio LV 《Journal of the experimental analysis of behavior》2003,79(1):111-135
Environmental stimuli that set the occasion wherein drugs are acquired can "trigger" drug-related behavior. Investigating the stimulus control of drug self-administration in laboratory animals should help us better understand this aspect of human drug abuse. Stimulus control of cocaine self-administration was generated here for the first time using multiple and chained schedules with short, frequently-alternating components--like those typically used to study food-maintained responding. The procedures and results are presented along with case histories to illustrate the strategies used to produce this stimulus control. All these multicomponent schedules contained variable-interval (VI) components as well as differential-reinforcement-of-other-behavior (DRO) or extinction components. Schedule parameters and unit dose were adjusted for each rat to produce stable, moderate rates in VI components, with minimal postreinforcement (infusion) pausing, and response cessation in extinction and DRO components. Whole-body drug levels on terminal baselines calculated retrospectively revealed that all rats maintained fairly stable drug levels (mean, 2.3 to 3.4 mg/kg) and molar rates of intake (approximately 6.0 mg/kg/hr). Within this range, no relation between local VI response rates and drug level was found. The stimulus control revealed in cumulative records was indistinguishable from that achieved with food under these schedules, suggesting that common mechanisms may underlie the control of cocaine- and food-maintained behavior. 相似文献