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81.
A new multiobjective linear programming (MOLP) algorithm is presented. The algorithm uses a variant of Karmarkar's interior-point algorithm known as the affine-scaling primal algorithm. Using this single-objective algorithm, interior search directions are generated and used to provide an approximation to the gradient of the (implicitly known) utility function. The approximation is guided by assessing locally relevant preference information for the various interior directions through interaction with a decision maker (DM). The resulting algorithm is an interactive approach that makes its progress towards the solution through the interior of the constraints polytope.  相似文献   
82.
Abstract

Optic 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   
83.
The Borg centiMax Scale, is a psychophysically composed general intensity ratio scale, which could enable more precise inter- and intraindividual comparisons of the intensity of depressive symptoms. In the present study, the properties of the centiMax scale were examined in 38 patients with clinical depression and 109 students. Additionally, preliminary centiMax cut-off scores for mild, moderate and severe depression were estimated. The psychometric properties of the centiMax were found to be satisfactory regarding internal consistency, convergent, discriminative and predictive validity. Moreover, the centiMax was demonstrated to provide meaningful comparisons of symptom intensity, which makes it possible to evaluate the relative importance of individual symptoms in a profile and make more precise comparisons within and between individuals. With regard to intraindividual comparisons, patients rated , for example, the intensity of feeling “guilt” twice as strong as feelings of “being punished,” and the intensity of “loss of pleasure” almost three times as strong as “being punished.” With regard to interindividual comparisons, patients rated e.g., the intensity of “being punished” as 12 times stronger than controls, and the intensity of “worthlessness” about nine times stronger. In conclusion, the centiMax was shown to be reliable and valid for assessing depressive symptoms. The centiMax with level anchored ratio data, appears to be highly advantageous as it permits rather precise values of symptom intensity for intra- and interindividual comparisons that could be useful in the diagnostic process and in treatment planning.  相似文献   
84.
The present study explored the intrinsic event-related potential (ERP) features of the effects of acute psychological stress on the processing of motion-in-depth perception using a dual-task paradigm. After a mental arithmetic task was used to induce acute psychological stress, a collision task was used to evaluate motion-in-depth perception. The error value and average amplitude of late slow waves (SW) were significantly larger for the earlier colliding spheres’ than for the later colliding spheres. The P1 peak latency in the left occipital region was significantly shorter than that of the right occipital region in the motion-in-depth perception task. Compared to the control condition, the estimated value of residual time-to-collision and error value were significantly reduced, and the N1 peak amplitude and the SW averaged amplitude were significantly increased in the stress condition. Longer motion-in-depth time improved discrimination accuracy and decreased the investment of cognitive resources. Acute psychological stress increased behavioral performance and enhanced attention resources on the motion-in-depth perception task together with greater investment of cognitive resources.  相似文献   
85.
A growing body of recent research suggests that verbal categories, particularly labels, impact categorization and perception. These findings are commonly interpreted as demonstrating the involvement of language on cognition; however, whether these assumptions hold true for grammatical structures has yet to be investigated. In the present study, we investigated the extent to which linguistic information, namely, grammatical gender categories, structures cognition to subsequently influence categorical judgments and perception. In a nonverbal categorization task, French–English bilinguals and monolingual English speakers made gender-associated judgments about a set of image pairs while event-related potentials were recorded. The image sets were composed of an object paired with either a female or male face, wherein the object was manipulated for their conceptual gender relatedness and grammatical gender congruency to the sex of the following target face. The results showed that grammatical gender modulated the N1 and P2/VPP, as well as the N300 exclusively for the French–English bilinguals, indicating the inclusion of language in the mechanisms associated with attentional bias and categorization. In contrast, conceptual gender information impacted the monolingual English speakers in the later N300 time window given the absence of a comparable grammatical feature. Such effects of grammatical categories in the early perceptual stream have not been found before, and further provide grounds to suggest that language shapes perception.  相似文献   
86.
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   
87.
宋仕婕  佐斌  温芳芳  谭潇 《心理学报》2020,52(8):993-1003
通过实验研究了群际互动中个体对不同来源身份的消极群体评价的情绪反应及群体认同的调节作用, 并从情绪-行为反应的连续性视角探索群际敏感效应的行为表现及内在机制。结果发现:(1)相比内群体的消极群体评价, 外群体的消极群体评价更能引起消极情绪反应; (2)群体认同对群际敏感效应起调节作用, 高群体认同者对来自外群体消极评价的情绪反应更加负面, 而低群体认同者这种趋势并不明显; (3)高群体认同者在经历外群体的消极群体评价后会表现出更多的内群体积极行为, 且消极情绪反应对此起中介作用。研究扩展了群际敏感效应的适用范围, 并为探讨其内部机制和后续影响提供了新的研究思路。  相似文献   
88.
华艳  李明霞  王巧婷  冯彩霞  张晶 《心理学报》2020,52(9):1048-1056
前人研究表明自动情绪调节能够自上而下地影响情绪及情绪性注意过程。近来有研究提示自动情绪调节与眶额皮层(orbitofrontal cortex, OFC)有关。也有研究表明左侧OFC的激活影响负性注意偏向。本研究采用经颅直流电刺激技术, 考察阈下启动情绪控制目标条件下, 抑制左侧眶额皮层兴奋性是否影响负性注意偏向。结果发现, 使用阴极刺激抑制左侧OFC活动可以加快被试对与恐惧刺激位置一致的探测点的反应。该结果提示左侧眶额皮层是自动情绪调节下情绪性注意选择相关的重要脑区。  相似文献   
89.
Attention-Deficit/Hyperactivity Disorder (ADHD) is related to suboptimal decision making in experimental tasks and to real-life risk-taking behavior (RTB) such as substance abuse and unsafe traffic conduct. In this preregistered study, we tested whether these associations are mediated by need for cognition—the extent to which one tends towards, and enjoys, analytical thought. In a large sample of young adults (N = 463, Mage = 19.7 years), we tested whether need for cognition mediated the association between self-reported ADHD symptoms on the one hand and decision-making strategy complexity on an experimental gambling task and self-reported real-life RTB on the other hand. Preregistered confirmatory analyses indicated first that ADHD symptoms were positively associated with real-life RTB, but the association was not mediated by need for cognition. Second, ADHD symptoms were not related to decision-making strategy complexity, and need for cognition was not a significant mediator. Explorative analyses revealed that (a) need for cognition was associated with higher decision-making accuracy and slower reaction time; (b) need for cognition was related to inattentive but not to hyperactive/impulsive ADHD symptoms; (c) need for cognition was associated with health-related RTB but not interpersonal RTB; and (4) only the association between inattention and health-related RTB was mediated by need for cognition. We conclude that need for cognition is not a mediator in the association between ADHD symptoms and RTB. Additionally, we conclude that neither ADHD symptoms nor need for cognition predict decision-making strategy complexity. Implications for both future research and clinical practice are discussed.  相似文献   
90.
《Médecine & Droit》2020,2020(160):6-9
Announcing a death is always a delicate moment for close familial members but also for caregivers. Law gives some precisions about how this information must be delivered. Recently the state council judged that the lack of empathy from caregivers and the late of the death announcement can create a damage. This judgement gives more precisions about how a death announcement must be in a hospital. This topic is pretty similar with the information which must be given to close familial members about organ donation. This latter is definitely more exceptional and the procedure is a way more regulated. There are much rules which explain how this information must be delivered.  相似文献   
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