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911.
Roman Duncko Linda Johnson Kathleen Merikangas Christian Grillon 《Neurobiology of learning and memory》2009,91(4):377-381
Effects of acute stress exposure on learning and memory have been frequently studied in both animals and humans. However, only a few studies have focused specifically on working memory performance and the available data are equivocal. The present study examined working memory performance during the Sternberg item recognition task after exposure to a predominantly adrenergic stressor. Twenty four healthy subjects were randomly assigned to a stress group or a control group. The stress group was exposed to the cold pressor stress test (CPS; i.e. insertion of the dominant hand into ice water for 60s), while 37 °C warm water was used with the control group. Twenty minutes after the stress exposure, working memory performance was tested with the Sternberg item recognition task with three levels of cognitive load. Sympathetic nervous system and hypothalamic pituitary adrenocortical (HPA) axis activation during CPS, were assessed by measuring heart rate and salivary cortisol before and during (heart rate) or 30 min after (cortisol) the stress procedure. Exposure to the CPS test was associated with a significant increase in heart rate but no increase in salivary cortisol. Participants exposed to the stress procedure showed significantly shorter reaction times during trials with higher cognitive load but tended to show higher false alarm rates than control subjects. The present results indicate that exposure to CPS can be associated with signs of both enhanced and impaired working memory performance. The observed behavioral pattern might represent a form of streamlined information processing advantageous in a threatening situation. 相似文献
912.
Does real time coupling between mental and physical activity early in development have functional significance? To address this question, we examined the habituation of visual attention and the subsequent response to change in two groups of 3‐month‐olds with different patterns of movement–attention coupling. In suppressors, the typical decrease in body movement at the onset of looks persists into the looks. In rebounders, the initial decrease is more transient and movement quickly returns above baseline. Suppressors and rebounders did not differ on measures of looking during habituation, but when the stimulus changed rebounders looked more than suppressors. When it did not change, they looked less. In addition, during habituation rebounders spent more time looking away from the stimulus. Rapid motor reactivation soon after gaze locks onto a target, characteristic of rebounders, may influence visual foraging and the response to change by keeping attention near a threshold of engagement. 相似文献
913.
This randomized controlled pilot study compared a cognitive-behavioral therapy (Seeking Safety; SS) plus treatment-as-usual (TAU) to TAU-alone in 49 incarcerated women with substance use disorder (SUD) and posttraumatic stress disorder (PTSD; full or subthreshold). Seeking Safety consisted of a voluntary group treatment during incarceration and individual treatment after prison release. TAU was required in the prison and comprised 180 to 240 hours of individual and group treatment over 6 to 8 weeks. Assessments occurred at intake, 12 weeks after intake, and 3 and 6 months after release from prison. There were no significant differences between conditions on all key domains (PTSD, SUD, psychopathology, and legal problems); but both conditions showed significant improvements from intake to later time points on all of these outcomes across time. Secondary analyses at follow-up found trends for SS participants improving on clinician-rated PTSD symptoms and TAU participants worsening on self-reported PTSD symptoms. Also, SS demonstrated continued improvement on psychopathology at 3 and 6 months, whereas TAU did not. However, alcohol use improved more for TAU during follow-up. Satisfaction with SS was high, and a greater number of SS sessions was associated with greater improvement on PTSD and drug use. Six months after release from prison, 53% of the women in both conditions reported a remission in PTSD. Study limitations include lack of assessment of SS outcomes at end of group treatment; lack of blind assessment; omission of the SS case management component; and possible contamination between the two conditions. The complex needs of this population are discussed. 相似文献
914.
Perceptions of the organizational context and psychological contract breach: Assessing competing perspectives 总被引:1,自引:0,他引:1
Christopher C. Rosen Chu-Hsiang Chang Russell E. Johnson Paul E. Levy 《Organizational behavior and human decision processes》2009,108(2):202-217
This study examines how employees’ perceptions of specific features of the organizational context—organizational politics and procedural justice—are related to their evaluations of psychological contract breach and subsequent attitudes and behaviors. Across three studies, we examined the appropriateness of four models for describing relationships among the focal constructs. Results of these studies support (a) an environmental responsiveness model in which psychological contract breach mediates the effects of politics and justice on employee outcomes, and (b) a general fairness evaluation model where politics, justice, and psychological contract breach serve as indicators of a higher order factor that predicts employee attitudes and behavior. Implications and directions for future research are presented. 相似文献
915.
The present study examined and compared order memory for a list of sequentially presented odours, unfamiliar faces, and pure tones. Employing single-probe serial position recall and following a correction for a response bias, qualitatively different serial position functions were observed across stimuli. Participants demonstrated an ability to perform absolute order memory judgments for odours. Furthermore, odours produced an absence of serial position effects, unfamiliar faces produced both primacy and recency, and pure tones produced recency but not primacy. Such a finding is contrary to the proposal by Ward, Avons, and Melling (2005) that the serial position function is task, rather than modality, dependent. In contrast, the observed functions support a modular conceptualization of short-term memory (e.g., Andrade & Donaldson, 2007; Baddeley & Hitch, 1974), whereby separate modality-specific memorial systems operate. An alternative amodal interpretation is also discussed wherein serial position function disparities are accommodated via differences in the psychological distinctiveness of stimuli (Hay, Smyth, Hitch, & Horton, 2007). 相似文献
916.
A Role for the X Chromosome in Sex Differences in Variability in General Intelligence? 总被引:1,自引:0,他引:1
ABSTRACT— There is substantial evidence that males are more variable than females in general intelligence. In recent years, researchers have presented this as a reason that, although there is little, if any, mean sex difference in general intelligence, males tend to be overrepresented at both ends of its overall distribution. Part of the explanation could be the presence of genes on the X chromosome related both to syndromal disorders involving mental retardation and to population variation in general intelligence occurring normally. Genes on the X chromosome appear overrepresented among genes with known involvement in mental retardation, which is consistent with a model we developed of the population distribution of general intelligence as a mixture of two normal distributions. Using this model, we explored the expected ratios of males to females at various points in the distribution and estimated the proportion of variance in general intelligence potentially due to genes on the X chromosome. These estimates provide clues to the extent to which biologically based sex differences could be manifested in the environment as sex differences in displayed intellectual abilities. We discuss these observations in the context of sex differences in specific cognitive abilities and evolutionary theories of sexual selection. 相似文献
917.
Twelve infants and toddlers who exhibited spontaneous awakening and crying episodes during the night were subjected to scheduled awakenings by their parents. Scheduled awakenings were determined from individual baseline data, and these consisted of awakening, feeding, and consoling the child about 15 to 30 minutes before typical spontaneous awakening times. Once spontaneous awakenings were precluded, scheduled awakenings by the parents were faded out and posttreatment data were collected. The technique appeared effective for most children when the parents complied with the procedure. 相似文献
918.
919.
Karen Ostrov Jerome Dowling David O. Wesner Frank K. Johnson 《Infant mental health journal》1982,3(3):162-173
Infant psychotherapy, in which the mother is requested to follow the baby's activities without initiating or directing, is described. Mothers demonstrate different styles of involvement with their infants: a protective mode, a prohibitive mode, a competitive mode, and other ways of interfering with their infants' tendency to explore the environment. Attempts to analyze such factors as position, distance and movement are discussed. Research for recording and analyzing the movement of infant and mother dyads is proposed. 相似文献
920.