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951.
Previous work employing graph theory and nonlinear analysis has found increased spatial and temporal disorder, respectively, of functional brain connectivity in schizophrenia. We present a new method combining graph theory and nonlinear techniques that measures the temporal disorder of functional brain connections. Multichannel electroencephalographic data were windowed and functional networks were reconstructed using the minimum spanning trees of correlation matrices. Using a method based on Shannon entropy, we found elevated connection entropy in gamma activity of patients with schizophrenia; however, gamma connection entropy remained elevated in patients with schizophrenia even after a reduction in symptoms due to treatment with antipsychotics. Our results are consistent with several possibilities: (1) aberrant functional connectivity is epiphenomenal to schizophrenia, (2) aberrant functional connectivity is a central feature but antipsychotics reduce symptoms by an independent mechanism, or (3) connection entropy is not an appropriately sensitive measure of brain abnormalities in schizophrenia.  相似文献   
952.
The 2008 recession reportedly led to the demise of conspicuous consumption with wealthy consumers abandoning luxury goods that prominently display their brands for more subdued designs. Utilizing data collected before and in the midst of the recession from designer handbag manufacturers, Louis Vuitton and Gucci, we find products introduced during the recession actually display the brand far more prominently than those products withdrawn. Data from Hermès and luxury ads in Vogue magazine also indicate manufacturers did not tone things down. Our results suggest conspicuous consumption endures in recessions; consumers who do not exit the luxury goods market are still interested in logo‐laden products.  相似文献   
953.
Brain complexity varies across many orders of magnitude between animals, and it is often assumed that complexity underpins cognition. It is thus important to explore the cognitive capacity of widely used model organisms such as Drosophila. We systematically investigated the fly’s ability to learn discriminations involving compound olfactory stimuli associated with shock. Flies could distinguish binary mixtures (AB+ CD-), including overlapping mixtures (AB+ BC-). They could learn positive patterning (AB+ A- B-) but could not learn negative patterning (A+ B+ AB-) or solve a biconditional discrimination task (AB+ CD+ AC- BD-). Learning about the elements of a compound (AB+) was not affected by prior conditioning of one of the elements (A+ AB+): flies do not exhibit blocking in this task. We compare these results with the predictions from simulation of several well-known theoretical models of learning, and find none are fully consistent with the overall pattern of observed behaviour.  相似文献   
954.
Infants, toddlers and preschoolers are a high risk group for exposure to trauma. Young children are also vulnerable to experiencing adverse outcomes as they are undergoing a rapid developmental period, have limited coping skills and are strongly dependent on their primary caregiver to protect them physically and emotionally. However, although millions of young children experience trauma each year, this population has been largely neglected. Fortunately, over the last 2 decades there has been a growing appreciation of the magnitude of the problem with a small but expanding number of dedicated researchers and clinicians working with this population. This review examines the empirical literature on trauma in young children with regards to the following factors: (1) how trauma reactions typically manifest in young children; (2) history and diagnostic validity of posttraumatic stress disorder (PTSD) in preschoolers; (3) prevalence, comorbidity and course of trauma reactions; (4) developmental considerations; (5) risk and protective factors; and (6) treatment. The review highlights that there are unique developmental differences in the rate and manifestation of trauma symptomatology, the current Diagnostic and Statistical Manual of Mental Disorders (4th ed., DSM-IV-TR) PTSD criteria is not developmentally sensitive and the impact of trauma must be considered within the context of the parent–child relationship. Recommendations for future research with this population are also discussed.  相似文献   
955.
Online chatting is an important component of improving interpersonal relationships online, but it may reduce participants' communication time with family members. We conducted a study of the relationship between participants' intent to engage in online chatting and three dimensions of loneliness: social, familial, and romantic. This study was designed to show the effect of online chatting on each of these three dimensions of loneliness. The participants in the study were 709 students at two universities in Taiwan who were classified on the basis of whether or not they had ever engaged in online chatting. Of the participants, 651 (91.82%) fully completed the questionnaires that served as the study instruments and were included in data analysis. The study found that individuals who had participated in online chatting exhibited greater familial loneliness than those who had not because the time spent in online chatting reduced the time spent in familial relationships. Social loneliness was related to the quality of Internet relationships rather than to the time spent online. Individuals who participated in online chatting had less romantic loneliness because of a greater ease of maintaining romantic relationships online. We conclude that online chatting can reduce social loneliness through high-quality Internet relationships but may exacerbate familial loneliness.  相似文献   
956.
Some studies on mental health outcomes research have found that when clients and therapists are ethnically or racially matched, this tends to be related to greater satisfaction and better outcomes. However, the precise underlying mechanism for the match effect has not been extensively examined. In this experimental study, we tested the effect of racial match on critical counseling processes (i.e., therapist credibility and the working alliance) using a sample of 171 Asian American respondents. We also examined Asian ethnic identification as a potential moderator of the racial match effect. Structural equation modeling analyses indicated that racially matched individuals perceived greater experiential similarity with the therapist than nonmatched individuals, and experiential similarity was positively associated with therapist credibility. Although racial match did not predict attitudinal similarity, attitudinal similarity was strongly related to the working alliance and therapist credibility. Counseling implications are discussed.  相似文献   
957.
Most research based on Fitts' law define a log-linear relationship between temporal and spatial accuracy in goal-directed aiming tasks using stationary targets. Whether this relationship holds or not when the targets have varying velocities, and how the behavioral strategies and physical activities may change accordingly are of interest. The aim of this study was to investigate the relationship between temporal and spatial accuracy in goal-directed aiming tasks with moving targets. Participants were asked to aim at two target widths using a joystick. Results demonstrated that in a goal-directed aiming task there was a negative effect on performance when target velocity was increased or target width was decreased. Participants moved faster and then made more systematic errors in a high-velocity target condition. Results may be applicable to the complex perceptual-motor behavior of people who perform tasks using computers.  相似文献   
958.
To reproduce the duration of an event precisely, one needs to represent the temporal information without being influenced by other magnitude attributes (e.g., size) of the event. In the present study, however, task-irrelevant numerical magnitude automatically affected participants' reproduction of the duration of a stimulus. In Experiment 1, participants made key-press responses to reproduce the duration of numbers. Reproduced durations were shorter for small numbers (e.g., 1) than for large numbers (e.g., 9). In contrast, in Experiment 2, participants' reproductions of a standard duration were longer when their key-press response was accompanied by visual presentation of a small number than when it was accompanied by presentation of a large number. These results clearly demonstrate that number-time interference extends beyond simple mapping between stimulus categories and response alternatives. The findings support the notion that either a common magnitude representation or closely connected magnitude representations underlie numerical and temporal processing.  相似文献   
959.
While there has been steady progress in identifying psychophysiological traits associated with psychopathy, most of the existing research has been carried out using incarcerated male participants, and data that include females are particularly rare. This study examined both affective startle blink modulation and P3 amplitude in a sample of female undergraduates grouped by scores on the Psychopathic Personality Inventory-Revised (PPI-R). Those scoring high for psychopathic traits lacked startle blink potentiation and demonstrated larger P3 amplitudes during auditory and visual oddball tasks. These data support the generalizability of deficient startle potentiation to non-incarcerated females with psychopathic traits, and add to a growing body of literature suggesting that psychopathic traits are associated with distinctive information-processing characteristics as indexed by P3 amplitude.  相似文献   
960.
Previous studies have shown the appearance of right-sided language-related brain activity in right-handed patients after a stroke. Non-invasive brain stimulation such as transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) have been shown to modulate excitability in the brain. Moreover, rTMS and tDCS have been found to improve naming in non-fluent post-stroke aphasic patients. Here, we investigated the effect of tDCS on the comprehension of aphasic patients with subacute stroke. We hypothesized that tDCS applied to the left superior temporal gyrus (Wernicke’s area) or the right Wernicke’s area might be associated with recovery of comprehension ability in aphasic patients with subacute stroke. Participants included right-handed subacute stroke patients with global aphasia due to ischemic infarct of the left M1 or M2 middle cerebral artery. Patients were randomly divided into three groups: patients who received anodal tDCS applied to the left superior temporal gyrus, patients who received cathodal tDCS applied to the right superior temporal gyrus, and patients who received sham tDCS. All patients received conventional speech and language therapy during each period of tDCS application. The Korean-Western Aphasia Battery (K-WAB) was used to assess all patients before and after tDCS sessions. After intervention, all patients had significant improvements in aphasia quotients, spontaneous speech, and auditory verbal comprehension. However, auditory verbal comprehension improved significantly more in patients treated with a cathode, as compared to patients in the other groups. These results are consistent with the role of Wernicke’s area in language comprehension and the therapeutic effect that cathodal tDCS has on aphasia patients with subacute stroke, suggesting that tDCS may be an adjuvant treatment approach for aphasia rehabilitation therapy in patients in an early stage of stroke.  相似文献   
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