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131.
132.
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   
133.
Adult, laboratory-reared, and singly caged field crickets, Gryllus integer, of known ages and representing F1 to F4 generations, were exposed to 15–20-minute bouts of social interaction with introduced adult intruder males on alternate days from approximately 1 week after adult molt to time of death. A total of 3,523 paired-male bouts for 116 male G. integer were recorded over a 2.5-year study period. Adult males used as intruders were wild-caught or laboratory reared G. integer, but for nine of the 116 experimental males, wild-caught intruders of a closely related sympathetic species, G. alogus, were used for all or many of the bouts. Bouts between male G. integer and conspecific intruders were characterized by significantly elevated levels of aggression (t=6.04, P<0.001) compared with males exposed to heterospecific G. alogus intruders in interspecific interactions. Significant differences (p<0.005, chi-squared test of independence) existed at four out of five levels in a hierarchy of agonistic behaviors. Most G. integer males exposed to both G. integer and G. alogus intruders showed significantly reduced aggression levels during the interspecific interactions (p<0.001, Mann-Whitney U test). Conspecific G. integer dyads in the intraspecific interactions showed significantly stable dominant-subordinate relationships over time. Confusion surrounding the use of the term aggression is described with reference to Arthropods in general and Orthopteran insects in particular, and some likely proximate and ultimate bases for reduced interspecific aggression in field crickets are discussed.  相似文献   
134.
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   
135.
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   
136.
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   
137.
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   
138.
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   
139.
Friendship patterns of 117 children with learning disabilities (LD) and 115 children without LD in Grades 4–8 were examined. In comparison with children without LD, boys with LD had fewer mutual friends, children with LD had more friends with learning problems and more younger friends, and children with LD in Grades 4–6 had less stable relationships. With regard to friendship quality, children with LD reported higher levels of conflict, lower levels of validation, and more problems with relationship repair than did children without LD. The findings were discussed in terms of factors that have been found to enhance friendship such as proximity and similarity, and the social skills difficulties that have been associated with learning disabilities.  相似文献   
140.
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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