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871.
The Sustained Attention to Response Task (SART) is a Go–No-Go signal detection task developed to measure lapses of sustained conscious attention. In this study, we examined the impact global interference and spatial uncertainty has on SART performance. Ten participants performed either a SART (high-Go) or a traditionally formatted (low-Go) version of a global–local stimuli detection task with spatially certain and uncertain signals. Reaction time in the SART was insensitive to global interference and spatial uncertainty, whereas reaction time in the low-Go task was sensitive. Spatial uncertainty increased errors of omission in the SART, which was not expected if the SART measures mindlessness. There was a high correlation between participants’ errors of commission rate and their reaction time in the SART. The results, overall, support the view that the SART is a better measure of response strategy than lapses in sustained attention or mindlessness.  相似文献   
872.
We conducted an assessment of self-control and impulsivity with 9 children referred to an outpatient clinic for impulsive, inattentive, and hyperactive behaviors. Each condition of the assessment consisted of a choice between 2 concurrently presented math or writing tasks, with 1 alternative reflecting impulsive responding and 1 alternative reflecting self-control. For the participants who demonstrated impulsive responding in 1 of 2 baseline conditions, we systematically varied reinforcer quality, delay to reinforcement, and response effort to evaluate the effects of these dimensions on the participants’ choices. Results of the assessment revealed that 3 participants displayed self-control responding, and 6 participants displayed impulsive responding during baseline conditions. Of the participants who displayed initial impulsivity, all showed self-control when 1 or more response or reinforcement dimensions were modified to bias responding within a brief multielement design. Results provide a unique application of concurrent schedules for conducting a brief assessment of impulsive responding in an outpatient clinical setting.  相似文献   
873.
This paper reports data from a qualitative study of patient experiences of DNA testing and cascade screening for hypertrophic cardiomyopathy and long QT syndrome, cardiac conditions that place sufferers at risk of sudden death. The paper particularly focuses on potential impediments to testing and screening. Semi-structured interviews were undertaken with a purposive sample of 27 people in the UK who had undergone testing. In the context of the uncertainties that can characterize experiences of these disorders, the majority of participants in this sample embraced testing and screening as a way of providing health information for themselves or their relatives (particularly children). There was nevertheless evidence of ambivalence about the value and impact of the DNA test information which could influence participants’ dispositions toward testing, and play into dilemmas about family communication. Other concerns arose in relation to communicating about these disorders, decisions to involve elderly relatives and pressures relating to family responsibility. The evidence of ambivalence provides insight into why some people may be resistant to testing, screening and sharing information. The findings about communication processes indicate potential areas of concern for the cascading process.  相似文献   
874.
The present research concerns the hypothesis that intuitive estimates of the arithmetic mean of a sample of numbers tend to increase as a function of the sample size; that is, they reflect a systematic sample size bias. A similar bias has been observed when people judge the average member of a group of people on an inferred quantity (e.g., a disease risk; see Price, 2001; Price, Smith, & Lench, 2006). Until now, however, it has been unclear whether it would be observed when the stimuli were numbers, in which case the quantity need not be inferred, and “average” can be precisely defined as the arithmetic mean. In two experiments, participants estimated the arithmetic mean of 12 samples of numbers. In the first experiment, samples of from 5 to 20 numbers were presented simultaneously and participants quickly estimated their mean. In the second experiment, the numbers in each sample were presented sequentially. The results of both experiments confirmed the existence of a systematic sample size bias.  相似文献   
875.
Theories of postformal thought (PFT) suggest that cognitive development is enhanced by social interactions where differences must be negotiated. Friendships provide the potential for complex social interactions and are an ideal context in which to explore the relation between cognitive development and the negotiation of social differences. The present research is the first to directly explore the relation between close cross-category friendships and level of postformal cognitive reasoning among college students. Participants from two universities completed questionnaires assessing PFT and friendship characteristics. Results indicate that individuals reported more same-category versus cross-category friendships. This was true for sex, ethnicity, social class, sexual orientation, and age. In addition, individuals high in PFT had more social category differences in their existing close friendships than individuals low in PFT.  相似文献   
876.
The purpose of this study is to examine the association between parental socio-economic status (SES) and childhood neurocognition and behavior in children with chromosome 22q11.2 deletion syndrome (22q11DS). Although undoubtedly, the deletion of genes in the 22q11.2 interval is primarily responsible for the psychological manifestations, little is known about the role of the environment in either mitigating or contributing to these problems. We examined the association of parental socio-economic status (SES) with cognition and behavior in children with 22q11DS (n = 65) and matched healthy control subjects (n = 52), since SES is a component of family resources. We found that in children with 22q11DS, higher SES correlated with better overall functioning (p < .01) and social skills (p < .01), and less frequent oppositional defiant behavior (p < .001). These findings were in contrast to the control subjects in whom SES correlated with cognition and achievement, but not behavior. Our results indicate that environmental factors influence the behavioral phenotype in children with 22q11DS, providing a framework for developing appropriate interventions. As such, genetic counseling for families with 22q11DS may include consideration of family resources and inclusion of other health professionals, such as social workers, to explore with the family available social supports and resources.  相似文献   
877.
A video self‐monitoring treatment package was used to evaluate the procedural integrity of staff implementing behavioral guidelines for one child with autism. Staff members with low procedural integrity scores were asked to participate. The treatment package incorporated an implementation video which reviewed the relevant behavioral guidelines and a procedural integrity monitoring system. Each participant was taught to score a pre‐training video, which highlighted components of implementing behavioral guidelines, with a procedural integrity tool denoting correct implementation of the procedures. The participant then scored their own baseline video using a similar tool constructed to highlight the target student's behavior plan. Participant scores were compared to experimenter scores and verbal feedback was given by the experimenter if the scores varied. Results showed increased procedural integrity implementing the behavior guidelines from baseline to 100% implementation for two out of three participants. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
878.
Animals are often assumed to use highly conspicuous features of a goal to head directly to that goal (‘beaconing’). In the field it is generally assumed that flowers serve as beacons to guide pollinators. Artificial hummingbird feeders are coloured red to serve a similar function. However, anecdotal reports suggest that hummingbirds return to feeder locations in the absence of the feeder (and thus the beacon). Here we test these reports for the first time in the field, using the natural territories of hummingbirds and manipulating flowers on a scale that is ecologically relevant to the birds. We compared the predictions from two distinct hypotheses as to how hummingbirds might use the visual features of rewards: the distant beacon hypothesis and the local cue hypothesis. In two field experiments, we found no evidence that rufous hummingbirds used a distant visual beacon to guide them to a rewarded location. In no case did birds abandon their approach to the goal location from a distance; rather they demonstrated remarkable accuracy of navigation by approaching to within about 70 cm of a rewarded flower’s original location. Proximity varied depending on the size of the training flower: birds flew closer to a previously rewarded location if it had been previously signalled with a small beacon. Additionally, when provided with a beacon at a new location, birds did not fly directly to the new beacon. Taken together, we believe these data demonstrate that these hummingbirds depend little on visual characteristics to beacon to rewarded locations, but rather that they encode surrounding landmarks in order to reach the goal and then use the visual features of the goal as confirmation that they have arrived at the correct location.  相似文献   
879.
Successful navigation within an environment requires that the traveler establish the correct heading—a process referred to as orienting. Many studies have now shown that humans and non-human animals can use the geometric properties of an enclosure to orient. In the present study, two groups of Clark’s nutcrackers (Nucifraga columbiana) were trained, in a reference memory task, to find food hidden in one of four containers arranged to form a rectangular array. One group had unique objects placed next to each of the containers, whereas the second group had identical objects placed next to each of the containers. Here, I show for the first time that for the Clark’s nutcracker, the distinctive properties of these objects enhanced the encoding of the array’s geometry compared to the learning of geometric properties from an array of identical objects, which remained at chance after substantial amounts of training. Subsequent transformation tests showed that an object not associated with reward, but sharing the same geometric properties as the correct object, may have had inhibitory qualities. Furthermore, by systematically removing objects from the array, I show that although nutcrackers encoded the geometry of the array, they did not encode a complete featural representation of the objects within the array.  相似文献   
880.
Research supports the efficacy of both cognitive dissonance (CD) and healthy weight (HW) eating disorders prevention, and indicates that CD can be delivered by peer-facilitators, which facilitates dissemination. This study investigated if peer-facilitators can deliver HW when it is modified for their use and extended follow-up of peer-facilitated CD as compared to previous trials. Based on pilot data, we modified HW (MHW) to facilitate peer delivery, elaborate benefits of the healthy-ideal, and place greater emphasis on consuming nutrient dense foods. Female sorority members (N = 106) were randomized to either two 2-h sessions of CD or MHW. Participants completed assessment pre- and post-intervention, and at 8-week, 8-month, and 14-month follow-up. Consistent with hypotheses, CD decreased negative affect, thin-ideal internalization, and bulimic pathology to a greater degree post-intervention. Both CD and MHW reduced negative affect, internalization, body dissatisfaction, dietary restraint, and bulimic pathology at 14 months.  相似文献   
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