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41.
There is currently much interest in the potential impact of psychological factors on immune responses. An attempt was made to assess the effects of dominant/subordinate polarity in male mice on the cytotoxic activities of their natural-killer (NK) cells. On the basis of repeated agonistic encounters, categories of subordinate and dominat animals were selected. These animals were compared with manipulated controls (introduced to a novel test cage without an opponent on each occasion) and undisturbed controls (who remained in isolation without manipulation). In terms of NK activity, immunosuppression was observed in both dominant and subordinate categories when compared to undisturbed controls. There were, however, no differences between the fighting exposed subjects and the manipulated controls, suggesting that stress accounts for any changes. © 1994 Wiley-Liss, Inc.  相似文献   
42.
Differential reinforcement is a common treatment for escape-maintained problem behavior in which compliance is reinforced on a fixed-ratio (FR) 1 schedule with brief access to positive and/or negative reinforcement. Recent research suggests some individuals prefer to complete longer work requirements culminating in prolonged (i.e. accumulated) reinforcement periods relative to brief (i.e. distributed) periods, but prolonged work exposure may evoke problem behavior and prevent compliance from contacting reinforcement when treating escape-maintained problem behavior. We exposed 3 children with escape-maintained problem behavior to both distributed (FR 1 resulting in 30 s of reinforcement) and accumulated (FR 15 resulting in 7.5 min of reinforcement) arrangements to compare their efficacy in maintaining low levels of problem behavior. We then assessed participants' preferences for these conditions in a concurrent-chains arrangement. Accumulated-reinforcement arrangements did not occasion additional problem behavior, but rather resulted in consistently lower levels of problem behavior for 2 of 3 participants. Participants demonstrated idiosyncratic preferences.  相似文献   
43.
There are over 3,000 sleep related infant deaths each year in the United States. Attempts to teach medical personnel and parents safe infant sleep practices in the infant sleep training literature have demonstrated mixed results. Thus, strategies to teach arrangements of safe infant sleep environments warrant further investigation. Behavioral skills training (BST) is an evidence-based teaching strategy shown to successfully teach various safety skills to children and adults. The current study evaluated the effectiveness of behavioral skills training to teach safe infant sleep practices to typically developing adults. Specifically, differential responding was assessed across multiple environmental arrangements typical of contexts parents may be exposed to when putting an infant to sleep. BST significantly improved appropriate arrangement of a safe sleep environment for infants for all 8 participants.  相似文献   
44.
The purpose of the current study was to evaluate the effect of implementing differential reinforcement at different times relative to the onset of teaching new skills to learners with autism spectrum disorder. Specifically, we first determined the most efficient differential reinforcement arrangement for each participant. Using the most efficient arrangement, we evaluated if differential reinforcement from the immediate onset, early onset, or late onset is the most efficient for learners to acquire a new skill. Three children diagnosed with autism spectrum disorder who have a history of receiving intervention based on the principles of applied behavior analysis participated in this study. The immediate onset of differential reinforcement resulted in the most efficient instruction in 6 of 7 comparisons. The results are discussed in light of previous studies and suggestions for future research are provided.  相似文献   
45.
The American Academy of Pediatrics (2016a) has made several recommendations regarding the safe positioning of infants by caregivers, including placing infants in a supine position for sleep and in prone for supervised periods of tummy time. However, caregivers may have difficulty adhering with these recommendations. A small, but growing, number of behavior analytic studies have examined these infant safety recommendations and strategies for increasing adherence. This review describes behavior analytic research on infant positioning and provides suggestions for future research.  相似文献   
46.
This study was intended to probe the aggressive nature of monkey infant abuse by comparing the morphology of abusive behavior patterns with that of patterns allocated to both aggression and other categories of behavioral repertoires of macaques. This morphological analysis indicated that most abusive patterns should not be classified in the aggression category as they, at the motor end, differ greatly from macaque aggressive acts. In contrast, they perfectly resemble behaviors that monkeys usually display while manipulating inanimate objects. The implications of this finding for the pathogenic study of monkey infant abuse are discussed.  相似文献   
47.
A child's emotional and social development depends on the parents’ provision of optimal support. Many parents with perinatal distress experience difficulties in mastering parenthood and seek help from professionals within primary healthcare. A clinical project was launched in Stockholm, where psychodynamic psychotherapists provided short-term consultations at Child Health Centers. This study qualitatively explored parents’ experiences of perinatal distress and of receiving help by nurses and therapists in the project. Thirteen parents were interviewed, and their responses were analyzed with a hermeneutical method. Three main themes crystallized; accessibility of psychological help and detection of emotional problems; experiences of therapy at the Child Health Center; and the therapists’ technique. Parents were also clustered into three so-called ideal types: the insecure; parents in crisis; and parents with lifelong psychological problems. Parents experienced obstacles in accessing psychological care within primary healthcare. Psychotherapists with a holistic family perspective and who managed to oscillate between insight-promoting and supportive interventions were especially appreciated. Patient categories who benefitted from insight promotion and support, respectively, were identified.  相似文献   
48.
This study evaluated the effects of children with autism spectrum disorder engaging in socially acceptable singing on their vocal stereotypy. A multiple‐baseline across four participants with embedded multielement designs was used to assess the effects of the singing intervention upon later occurrence of vocal stereotypy for each participant. Results showed that fewer instances of vocal stereotypy occurred during and after singing intervention sessions. Additionally, two children began to emit appropriate singing after intervention, which suggests that the topography of their vocal stereotypy (e.g., monosyllabic or screeching sounds) was altered to some extent. Overall, results suggest positive implications for teaching appropriate vocal behaviors as functional replacements for vocal stereotypy.  相似文献   
49.
Infancy is marked by rapid neural and emotional development. The relation between brain function and emotion in infancy, however, is not well understood. Methods for measuring brain function predominantly rely on the BOLD signal; however, interpretation of the BOLD signal in infancy is challenging because the neuronal‐hemodynamic relation is immature. Regional cerebral blood flow (rCBF) provides a context for the infant BOLD signal and can yield insight into the developmental maturity of brain regions that may support affective behaviors. This study aims to elucidate the relations among rCBF, age, and emotion in infancy. One hundred and seven mothers reported their infants' (infant age M ± SD = 6.14 ± 0.51 months) temperament. A subsample of infants completed MRI scans, 38 of whom produced usable perfusion MRI during natural sleep to quantify rCBF. Mother‐infant dyads completed the repeated Still‐Face Paradigm, from which infant affect reactivity and recovery to stress were quantified. We tested associations of infant age at scan, temperament factor scores, and observed affect reactivity and recovery with voxel‐wise rCBF. Infant age was positively associated with CBF in nearly all voxels, with peaks located in sensory cortices and the ventral prefrontal cortex, supporting the formulation that rCBF is an indicator of tissue maturity. Temperamental Negative Affect and recovery of positive affect following a stressor were positively associated with rCBF in several cortical and subcortical limbic regions, including the orbitofrontal cortex and inferior frontal gyrus. This finding yields insight into the nature of affective neurodevelopment during infancy. Specifically, infants with relatively increased prefrontal cortex maturity may evidence a disposition toward greater negative affect and negative reactivity in their daily lives yet show better recovery of positive affect following a social stressor.  相似文献   
50.
Bilingual infants from 6‐ to 24‐months of age are more likely to generalize, flexibly reproducing actions on novel objects significantly more often than age‐matched monolingual infants are. In the current study, we examine whether the addition of novel verbal labels enhances memory generalization in a perceptually complex imitation task. We hypothesized that labels would provide an additional retrieval cue and aid memory generalization for bilingual infants. Specifically, we hypothesized that bilinguals might be more likely than monolinguals to map multiple perceptual features onto a novel label and therefore show enhanced generalization. Eighty‐seven 18‐month‐old monolingual and bilingual infants were randomly assigned to one of two experimental conditions or a baseline control condition. In the experimental conditions, either no label or a novel label was added during demonstration and again at the beginning of the test session. After a 24‐hr delay, infants were tested with the same stimulus set to test cued recall and with a perceptually different but functionally equivalent stimulus set to test memory generalization. Bilinguals performed significantly above baseline on both cued recall and memory generalization in both experimental conditions, whereas monolinguals performed significantly above baseline only on cued recall in both experimental conditions. These findings show a difference between monolinguals and bilinguals in memory generalization and suggest that generalization differences between groups may arise from visual perceptual processing rather than linguistic processing. A video abstract of this article can be viewed at https://youtu.be/yXB4pM3fF2k  相似文献   
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