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141.
Theory and research on self‐regulation, emotional adjustment, and interpersonal processes focus increasingly on parasympathetic functioning, using measures of vagally mediated heart rate variability (vmHRV) or respiratory sinus arrhythmia (RSA). This review describes models of vmHRV in these areas, and issues in measurement and analysis. We propose a framework organizing theory and research as examining (a) vmHRV as an individual difference or a situational response, and (b) resting, reactive, or recovery levels. Evidence supports interpretation of individual differences in resting vmHRV as a broad biomarker for adaptive functioning, but its specificity and underlying mechanisms require elaboration. Individual differences in vagal reactivity (i.e., trait‐like differences in vmHRV decreases during challenge or stress) are less commonly studied in adults and results are mixed. Many stressors and challenges evoke temporary decreases in vmHRV, and in some research self‐regulatory effort evokes increases. In a smaller literature, positive interpersonal experiences and some restorative processes increase resting vmHRV, whereas depletion of self‐regulatory capacity through related effort decreases it. Greater attention to conceptual distinctions regarding vmHRV constructs and several methodological issues will strengthen future research. Importantly, researchers should exercise caution in equating vmHRV with specific psychosocial constructs, especially in the absence of converging assessments and precise experimental manipulations.  相似文献   
142.
以往研究表明情绪背景对来源记忆存在影响,但背景的情绪效价和唤醒如何影响熟悉性及回想尚存争议。本研究以ERPs技术作为测量手段,采用来源记忆多键范式,操纵背景的情绪效价及唤醒强度,以探讨编码阶段背景情绪影响来源记忆提取的认知神经机制。学习阶段,呈现中性汉字及情绪图片(正性高唤醒、正性低唤醒、负性高唤醒、负性低唤醒);测验阶段,仅呈现汉字,被试进行五键判断。行为结果发现:来源正确的比率比来源错误的比率更高,反应时更短;同时提取正性背景的辨别力更强,反应时更短;提取高唤醒背景反应时更短。脑电结果发现了分别代表熟悉性及回想的FN400及LPC新旧效应,且在500~700 ms,提取正性背景及高唤醒背景诱发显著更正的ERPs,但效价与唤醒没有交互作用。总体来说,来源记忆中背景效价及唤醒度对回想过程存在独立影响,体现为正性背景及高唤醒背景对来源提取的促进作用。  相似文献   
143.
The purpose of this study was to determine the effects of teacher feedback delivered via a public address system on the off-task behavior of elementary-school physical education students. A multiple baseline design across three classes was used in this investigation. Results indicated a consistent decline in off-task behavior when the public address feedback system was used.  相似文献   
144.
This study investigated whether children's ability to reason about truths and lies influenced their truth-telling behavior. Four-six-year-old children (n=118) played a game that was intended to motivate children to use deception to hide a minor transgression. Next, an interviewer gave children one of four preliminary discussions. Children received a typical forensic truth/lie discussion (TLD), a developmentally appropriate and more elaborate TLD, or one of two discussions that controlled for the time spent conversing with children. Children were interviewed about the event. The results revealed that children's performance on the truth/lie questions did not predict their truth-telling behavior. Regardless of their performance on truth/lie questions, children who received TLD's gave more honest reports than children who did not receive TLD's. These results suggest that discussing truths and lies with children may promote truth-telling behavior. However, the results cast doubt on the validity of using children's performance on truth/lie questions as a measure of competency.  相似文献   
145.
Pigeons were trained to discriminate 5 mg/kg pentobarbital from saline under concurrent variable-ratio (VR) VR schedules, in which responses on the pentobarbital-biased lever were reinforced under the VR schedule with the smaller response requirements when pentobarbital was given before the session, and responses on the saline-biased key were reinforced under the VR schedule with the larger response requirements. When saline was administered before the session, the reinforcement contingencies associated with the two response keys were reversed. When responding stabilized under concurrent VR 20 VR 30, concurrent VR 10 VR 40, or concurrent VR 5 VR 50 schedules, pigeons responded almost exclusively on the key on which fewer responses were required to produce the reinforcer. When other doses of pentobarbital and other drugs were substituted for the training dose, low doses of all drugs produced responding on the saline-biased key. Higher doses of pentobarbital and chlordiazepoxide produced responding only on the pentobarbital-biased key, whereas higher doses of ethanol and phencyclidine produced responding only on this key less often. d-Amphetamine produced responding primarily on the saline-biased key. When drugs generalized to pentobarbital, the shape of the generalization curve under concurrent VR VR schedules was more often graded than quantal in shape. Thus, drug discrimination can be established under concurrent VR VR schedules, but the shapes of drug-discrimination dose-response curves under concurrent VR VR schedules more closely resemble those seen under interval schedules than those seen under fixed-ratio schedules. Graded dose-response curves under concurrent VR VR schedules may relate to probability matching and difficulty in discriminating differences in reinforcement frequency.  相似文献   
146.
The present experiment explored the effects of three variables on the spontaneous categorization of stimuli in perceptually distinct and novel domains. Each of six stimulus domains was created by morphing two images that were the domain endpoints. The endpoints of the domains were male and female faces, two abstract drawings, a car and a truck, two banded-elevation satellite land images, a tree and a cat, and two false-color satellite images. The stimulus variants at each end of a domain defined two potential perceptual classes. Training was conducted in a matching-to-sample format and used stimuli from one or two domains, one or three variants per class as samples, and one or three variants per class as comparisons. The spontaneous categorization of stimuli in the untrained stimulus domains showed the emergence of a generalized categorization repertoire. The proportion of spontaneously categorized stimuli in the new domains was positively related to the number of domains and samples used in training, and was inversely related to the number of comparisons used in training. Differential reaction times demonstrated the discriminability of the stimuli in the emergent classes. This study is among the first to provide an empirical basis for a behavior-analytic model of the development of generalized categorization repertoires in natural settings.  相似文献   
147.
Predictions made by 4 competing models of time use by children with AD/HD were tested using a computerized version of the Matching Familiar Figures Test in 2 studies. In Study 1 teacher-identified AD/HD children (N = 10) and non-AD/HD controls (N = 10) completed the task under 3 different trial duration conditions (5, 10, and 15 s). In Study 2 the same task was completed by a group of children with a diagnosis of Hyperkinetic Disorder (N = 12) and controls (N = 12). In both studies AD/HD children performed poorly on trials of both 5- and 15-s duration but as well as controls on the 10-s trials. This quadratic function provided support for the State Regulation Deficit model of time use in AD/HD. The value of tailoring the temporal features of learning contexts to the conceptual style of AD/HD children is discussed.  相似文献   
148.
Thirty preschoolers rated as hard to manage on Goodman's (R. Goodman, 1997) Strengths and Difficulties Questionnaire (SDQ), and a group of matched control children were observed and recorded on audiotape at home, interacting with their mothers (Time 1). At the 18-month follow-up home visits (Time 2), the children and mothers were filmed across 4 observation settings. Mother–child interactions were rated on affect, control, responsiveness and connectedness of communication. At Time 1, mothers of the hard to manage group used more negative control and engaged in fewer connected conversations than did mothers in the control group. At Time 2, mothers of the hard to manage group displayed higher levels of negative control and lower levels of positive control. These results are discussed in terms of the importance of examining connected communication and different observation contexts when examining dyadic mother–child interactions.  相似文献   
149.
Experiments have shown that human and nonhuman subjects are capable of performing new arbitrary stimulus-stimulus relations without error. When subjects that are experienced with matching-to-sample procedures are presented with a novel sample, a novel comparison, and a familiar comparison, most respond by correctly selecting the novel comparison in the presence of the new sample. This exclusion paradigm was expanded with two California sea lions that had previously formed two 10-member equivalence classes in a matching-to-sample procedure. Rather than being presented with a novel sample on a given trial, the sea lions were presented with a randomly selected familiar member of one class as the sample. One of the comparisons was a randomly selected familiar member of the alternative class, and the other was a novel stimulus. When required to choose which comparison matched the sample, the subjects reliably rejected the familiar comparison, and instead selected the unfamiliar one. Next, the sea lions were presented with transfer problems that could not be solved by exclusion; they immediately grouped the new stimuli into the appropriate classes. These findings show that exclusion procedures can rapidly generate new stimulus relations that can be used to expand stimulus classes.  相似文献   
150.
Examined patterns of friendship participation, stability, and quality among previously unfamiliar, ethnically diverse girls with attention-deficit/hyperactivity disorder (ADHD; n = 140) and comparison (n = 88) girls, aged 6–12 years, who attended 5-week naturalistic summer camps. Each girl completed sociometric nominations during Weeks 1, 3, and 5 of the camps; friendships were indexed by examining patterns of reciprocal nominations. At each assessment point, girls with ADHD had fewer mutual friends and were more likely to have no friends. Girls with Combined-type ADHD exhibited difficulties maintaining friendships from the beginning to middle of camp, whereas girls with Inattentive-type ADHD demonstrated poor friendship stability from the middle to end of camp. In general, girls with ADHD had higher levels of negative relationship features—including conflict and relational aggression—than did comparison girls, but levels of positive relationship features did not differ across subgroups. Friendship status predicted positive and negative peer regard, controlling for Verbal IQ and diagnostic status. Overall, although girls with ADHD were able to make friends to some extent, they differed from comparison girls in terms of the likelihood of doing so, the ability to maintain the friendships that they did form, and the levels of negative features found in their friendships.  相似文献   
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