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211.
失败的限制性饮食者是进食障碍的高危人群,他们面对食物时的抑制控制能力通常很弱,从而更易发展为肥胖,所以改善失败的限制性饮食者对不健康食物的进食选择十分重要。本文采用在线停止信号任务,通过提高失败的限制性饮食者对不健康食物图片的抑制控制能力,从而减少他们在日常生活中对不健康食物的选择。首先对66名失败的限制性饮食者实施前测,然后随机分为对不健康食物图片进行抑制反应的干预组(n=33)和对非食物图片进行抑制反应的控制组(n=31),两组被试接受每天一次(每次10 min左右)共计7次的训练。完成训练后,所有被试均接受后测。结果发现,干预训练后,与控制组相比,干预组被试对不健康食物的选择频率以及对不健康食物自我报告的吸引力和喜爱程度均显著降低。 相似文献
212.
The purpose of this study was to investigate and compare the mechanisms of brain activity, as revealed by a combination of the visuospatial attention shifting paradigm and event-related potentials (ERP) in children with developmental coordination disorder (DCD) and typically developing children. Twenty-eight DCD children and 26 typically developing children were recorded with regard to their behavioral performance and ERP measures during a variant of the endogenous Posner paradigm, in which they should react to visual targets preceded by spatial cues or presented uncued. Children with DCD showed longer reaction time and a deficit in inhibitory response capacity when compared to typically developing children. The electrophysiological characteristics also showed distinct modulatory effects upon attentional orienting, anticipatory mechanisms, and cognitive-to-motor transfer in children with DCD: longer cue-P3 and target-N1 latency, smaller target-P3 amplitude, an elongated interval between N2 and the motor response (N2-RT), and small areas on contingent negative variation (CNV). The combined analysis of behavioral performance and ERP data suggested that children with DCD had deficits of slower target identification (N1), less ability in interhemispheric (P3) and cognitive-to-motor transfer speed (N2-RT), as well as a less mature anticipatory and executive process (CNV). 相似文献
213.
This study compared the cognitive control skills of male incarcerated adolescents (n = 44), male control adolescents (n = 33), male incarcerated young adults (n = 41), and male control young adults (n = 35) using the AX-continuous performance test (AX-CPT). This test measures proactive control (the ability to maintain a mental representation of goal-related information in preparation for a behavioral response) and reactive control (the ability to activate goal-related information in response to an external trigger). Incarcerated individuals had more difficulty implementing proactive control, whereas control individuals had more difficulty implementing reactive control. Adolescents had more difficulty with both reactive and proactive control compared with young adults, suggesting that both skills improve with age. Additional analyses indicated that the effect of age on proactive control was due to the presence of attention-deficit/hyperactivity disorder, whereas the effect of age on reactive control appeared to be a natural developmental trend that could not be explained by other variables. These findings are considered in relation to the dual mechanisms of control theory [Braver, T. S., Gray, J. R., & Burgess, G. C. (2007). Explaining the many varieties of working memory variation: Dual mechanisms of cognitive control. In A. R. A. Conway, C. Jarrold, M. J. Kane, A. Miyake, & J. N. Towse (Eds.), Variation in Working Memory. New York: Oxford University Press.]. 相似文献
214.
Ullrich K.H. Ecker Anna M. Arend Kirstin Bergstrm Hubert D. Zimmer 《Consciousness and cognition》2009,18(3):679-689
Research on the effects of perceptual manipulations on recognition memory has suggested that (a) recollection is selectively influenced by task-relevant information and (b) familiarity can be considered perceptually specific. The present experiment tested divergent assumptions that (a) perceptual features can influence conscious object recollection via verbal code despite being task-irrelevant and that (b) perceptual features do not influence object familiarity if study is verbal-conceptual. At study, subjects named objects and their presentation colour; this was followed by an old/new object recognition test. Event-related potentials (ERP) showed that a study-test manipulation of colour impacted selectively on the ERP effect associated with recollection, while a size manipulation showed no effect. It is concluded that (a) verbal predicates generated at study are potent episodic memory agents that modulate recollection even if the recovered feature information is task-irrelevant and (b) commonly found perceptual match effects on familiarity critically depend on perceptual processing at study. 相似文献
215.
Preferred walking speed (PWS) reflects the integrated performance of the relevant physiological sub-systems, including energy expenditure. It remains unclear whether the PWS during over-ground walking is chosen to optimize one’s balance control because studies on the effects of speed on the body’s balance control have been limited. The current study aimed to bridge the gap by quantifying the effects of the walking speed on the body’s center of mass (COM) motion relative to the center of pressure (COP) in terms of the changes and directness of the COM-COP inclination angle (IA) and its rate of change (RCIA). Data of the COM and COP were measured from fifteen young healthy males at three walking speeds including PWS using a motion capture system. The values of IAs and RCIAs at key gait events and their average values over gait phases were compared between speeds using one-way repeated measures ANOVA. With increasing walking speed, most of the IA and RCIA related variables were significantly increased (p < 0.05) but not for those of the frontal IA. Significant quadratic trends (p < 0.05) with highest directness at PWS were found in IA during single-limb support, and in RCIA during single-limb and double-limb support. The results suggest that walking at PWS corresponded to the COM-COP control maximizing the directness of the RCIAs over the gait cycle, a compromise between the effects of walking speed and the speed of weight transfer. The data of IA and RCIA at PWS may be used in future assessment of balance control ability in people with different levels of balance impairments. 相似文献
216.
Thousands of adult pedestrians are killed or injured each year. In spite of ever growing knowledge of correlates of risk pedestrian behavior, much remains to be learned. A small body of research has applied the Theory of Planned Behavior (TPB) to the problem of risky crossing decisions. We employed TPB to examination of intentions to cross under varying types of distraction. Eighty adults completed measures of injury exposure, followed by a questionnaire structured around TPB assessing intentions to cross streets under common conditions of self-imposed distraction. Results were similar to other research, suggesting attitude and perceived behavioral control predicted intentions to cross streets while distracted. Results are discussed in the context of similar studies, and with regard to future directions and injury prevention efforts. 相似文献
217.
AbstractOptic flow (OF) has been utilized to investigate the sensory integration of visual stimuli during postural control. It is little known how the OF speed affects the aging brain during the sensory integration process of postural control. This study was to examine the effect of OF speeds on the brain activation using functional near-infrared spectroscopy (fNIRS) and postural sway between younger and older adults. Eleven healthy younger adults (5M/6F, age 22?±?1-year-old) and ten healthy older adults (4M/6F, age 71?±?5-year-old) participated in this study. A virtual reality headset was used to provide the OF stimulus at different speeds. A forceplate was used to record the center-of-pressure to compute the amplitude of postural sway (peak-to-peak). Compared with younger adults, older adults showed significantly increased activation in the OF speed of 10?m/s and decreased activation in the OF speed of 20?m/s in the left dorsolateral prefrontal cortex. Older adults also showed decreased activation in the left temporoparietal region (VEST) in the OF speed of 20?m/s. A significant difference in peak-to-peak was found between groups. Our results indicated that age might be associated with the ability to process fast OF stimulation. 相似文献
218.
Compton RJ Carp J Chaddock L Fineman SL Quandt LC Ratliff JB 《Brain and cognition》2007,64(3):247-256
This study tested the prediction that the error-related negativity (ERN), a physiological measure of error monitoring, would be enhanced in anxious individuals, particularly in conditions with threatening cues. Participants made gender judgments about faces whose expressions were either happy, angry, or neutral. Replicating prior studies, midline scalp negativities were greater following errors than following correct responses. In addition, state anxiety interacted with facial expression to predict ERN amplitudes. Counter to predictions, participants high in state anxiety displayed smaller ERNs for angry-face blocks and larger ERNs for happy-face blocks, compared to less anxious participants. These results are inconsistent with the simple notion that anxiety enhances error sensitivity globally. Rather, we interpret the findings within an expectancy violation framework, in which anxious participants have altered expectations for success and failure in the context of happy and angry facial cues, with greater ERN amplitudes when expectations are violated. 相似文献
219.
Preliminary evidence that acute and chronic daily psychological stress affect sexual arousal in sexually functional women 总被引:1,自引:0,他引:1
It is assumed that psychological stress may inhibit sexual arousal in women. Research on the effect of (acute and chronic) psychological stressors on genital and subjective sexual arousal, however, is scarce. To investigate whether psychological stressors indeed inhibit sexual responding, sexually functional women were randomly assigned to an experimental condition (n=30) in which acute psychological stress was induced by a frustrating computer task or a control condition (n=29). After the acute psychological stress or control induction women were exposed to an erotic stimulus. Genital sexual arousal was assessed using vaginal photoplethysmography. Self-report ratings of subjective sexual arousal were collected after the erotic stimulus. Furthermore, women were post hoc divided into a 'low' and a 'high' chronic stress group, based on their pre-assessment scores on a chronic daily stress questionnaire. As predicted, it was found that women in the acute stress condition responded with lower levels of genital and subjective sexual arousal to an erotic stimulus than women in the control condition. In addition, women with high levels of chronic stress responded with lower levels of genital sexual arousal to an erotic stimulus than women with low levels of chronic stress. Chronic stress did not affect the level of subjective sexual arousal. 相似文献
220.
Bobbi R. Walling Rosemary S. L. Mills Wendy S. Freeman 《Journal of child and family studies》2007,16(5):642-659
Psychological control is a pattern of parenting that is intrusive and manipulative of children's thoughts, feelings, and attachment
to parents. Although little is known about the determinants of psychological control, it has been linked to the psychological
status of the parent. We hypothesized that several parenting cognitions reflecting personal concerns would be associated with
the use of psychological control: low perceived control, sensitivity to hurt, and a disapproving attitude to negative emotion.
We also examined moderating associations with child temperament and child gender. Participants were 198 mothers and fathers
of 3- and 4-year-olds (106 boys, 92 girls; M age = 4.10 years, SD = 0.26). Parents completed self- and spouse-report measures of psychological control, rated their child's temperamental characteristics,
and completed measures of parenting cognitions. Predictions were generally supported for two of the three cognitions. Sensitivity
to hurt and disapproval of negative emotion were associated with more frequent reported use of psychological control. There
were some moderating effects of child characteristics. 相似文献