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41.
Auditory saltation is an illusion in which a train of clicks, the first half of which is presented at one location and the other half of which is presented from a second location, is perceived as originating not only from the anchor points, but also from locations between them. That is, intermediate members of the series of clicks have their spatial locations systematically misperceived. In the present study, auditory saltation was examined for the first time in the vertical midsagittal plane. Subjects rated the perceived continuity of motion for 8-click trains systematically varied in inter-click interval (ICI), direction of motion (up, down), and trial type ('saltation' versus 'real' motion). In all listeners, saltation stimuli supported robust saltation, but only for trials with ICIs less than about 120 ms. Real motion was rated as continuous for all ICIs. These data indicate that the auditory-saltation illusion can exploit monaural stimulus cues for source location in the generation of the illusory motion percept. 相似文献
42.
Guillem F Ganeva E Pampoulova T Stip E Lalonde P Sasseville M 《Brain and cognition》2005,57(1):93-101
This study was designed to investigate whether the neuropsychological correlates of the symptom dimensions of schizophrenia vary with the clinical state in patients followed from the acute to stable the phase of the illness. Fifteen patients were assessed for symptoms (SAPS-SANS) and undergone a complete neuropsychological assessment at two sessions. The first session (S1) was carried out within six days after admission, i.e., acute phase and the second (S2) at least two month after hospitalization, i.e., stable phase. The data were analyzed using stepwise regression models in which neuropsychological scores were in entered to predict each dimensional score. This analysis was applied on the S1 and S2 data as well as on the S2-S1 difference to assess the neuropsychological predictors of clinical changes. Generally, the results replicate the previous associations between neuropsychological and dimensional measures found in stable patients. In addition, this study shows if each dimension appears to rely on a key structure, symptom variations seems to involve changes in the spread of the dysfunction and/or changes in the connectivity between the key and other regions. The results also suggest that functional changes related to some symptoms dimensions occur to compensate for the dysfunction associated with other symptoms. 相似文献
43.
The purpose of this study was to examine the relationships between physical activity measured as pedometer steps and performance on three motor skill tests. A secondary purpose was to determine if middle school children are meeting the recommendation for the number of daily steps. A sample (n =217) of 6th, 7th and 8th grade students participated. Each subject wore a Digi-Walker pedometer for three consecutive days. Subjects additionally recorded their pedometer steps in two 45 min.-physical education classes. There were strong significant correlations between daily steps taken by boys and girls, pedometer steps during physical education class and the AAHPERD Passing Test and the Bass Stick Balance. Similar correlations were weaker for the Side-Step Agility Test. Multivariate analysis of variance was utilized to examine variability of the three skills test by sex and year in school. Differences between students in Grades 7 and 8 on the AAHPERD Passing Test were significant. In addition, significant differences between daily pedometer steps and steps during physical education between Grades 6 and 7 were observed. Boys and girls had similar means on the AAHPERD Passing Test and Bass Stick Balance Test, but not on the Side-Step Agility Test. Scores on the three movement skills tested in this study were not strongly related to physical activity of the entire sample. Steps taken by middle school children appear not to be related to these measures of motor skills. 相似文献
44.
In a recent study, Pelli (1999 Science 285 844-846) performed a set of perceptual experiments using portrait paintings by Chuck Close. Close's work is similar to the 'Lincoln' portraits of Harmon and Julesz (1973 Science 180 1194-1197) in that they are composite images consisting of coarsely sampled, individually painted, mostly homogeneous cells. Pelli showed that perceived shape was dependent on size, refuting findings that perception of this type is scale-invariant. In an attempt to broaden this finding we designed a series of experiments to investigate the interaction of 2-D scale and 3-D structure on our perception of 3-D shape. We present a series of experiments where field of view, 3-D object complexity, 2-D image resolution, viewing orientation, and subject matter of the stimulus are manipulated. On each trial, observers indicated if the depicted objects appeared to be 2-D or 3-D. Results for face stimuli are similar to Pelli's, while more geometrically complex stimuli show a further interaction of the 3-D information with distance and image information. Complex objects need more image information to be seen as 3-D when close; however, as they are moved further away from the observer, there is a bias for seeing them as 3-D objects rather than 2-D images. Finally, image orientation, relative to the observer, shows little effect, suggesting the participation of higher-level processes in the determination of the 'solidness' of the depicted object. Thus, we show that the critical image resolution depends systematically on the geometric complexity of the object depicted. 相似文献
45.
This study examined the effects on recall of story details of congruity or incongruity between the hedonic valence of literary texts and odours inhaled while reading them. During the reading session, 24 undergraduates (12 males and 12 females) read two passages involving positive subject matter and two with negative subject matter while sniffing pleasant or unpleasant odours in a within-subject fully counterbalanced design. Subjects rated their experience of each text on eleven 7-point scales. During the test session 48 hours later, subjects read a two-word title associated with each of the passages and inhaled the odour that was paired with it in the reading session. They also rated their experience on six of the scales that had been used during the reading session. Results showed that hedonic congruence between the passage and the odour fostered enhanced recall during the test session. The combination of positive subject matter and positive odour was reflected in more accurate recall of character details, while pairing negative subject matter and negative odour resulted in more accurate recall of setting details. Regression analysis showed that overall recall accuracy was increased by identifying with the characters in the stories and for passages that were found pleasing and personally meaningful. Consistent with the literature on implicit learning involving odours, recall accuracy varied inversely with perceived odour intensity. Implicit learning involving odours and literary passages is therefore fostered by unity in the reading experience. 相似文献
46.
Hollander E Phillips A King BH Guthrie D Aman MG Law P Owley T Robinson R 《CNS spectrums》2004,9(1):49-56
There are specific challenges to studying the design of pharmacologic trials in child/adolescent and adult autism, such as subject stratification and parallel versus crossover designs. This article describes how optimal study design is influenced by subject selection and outcome measures chosen. Lessons learned in study design from the Research Units on Pediatric Psychopharmacology Autism Network trial with risperidone, Seaver Center trials with fluoxetine and valproate, Dartmouth trials with amantadine, and National Institutes of Health secretin trials are highlighted. The Internet System for Assessing Autistic Children system for managing multicenter clinical trials in autism and statistical issues in autism research are also described. 相似文献
47.
48.
A meta-analytic review of prospective memory and aging 总被引:16,自引:0,他引:16
A meta-analysis of prospective memory (PM) studies revealed that in laboratory settings younger participants outperform older participants on tests of both time- and event-based PM (rs=-.39 and -.34, respectively). Event-based PM tasks that impose higher levels of controlled strategic demand are associated with significantly larger age effects than event-based PM tasks that are supported by relatively more automatic processes (rs=-.40 vs. -.14, respectively). However, contrary to the prevailing view in the literature, retrospective memory as measured by free recall is associated with significantly greater age-related decline (r=-.52) than PM, and older participants perform substantially better than their younger counterparts in naturalistic PM studies (rs=.35 and.52 for event- and time-based PM, respectively). 相似文献
49.
Despite the fact that inhalant use is a growing problem among youth in the United States, relatively little attention has been paid to the demographic and social factors related to its use. This study used data from a household survey of adolescents in Washington state, and found that race/ethnicity was a strong predictor of lifetime prevalence of inhalant use, with Native-American youth being particularly likely to use inhalants. Comparing the age at initiation of inhalant use to other legal and illegal substances, we found that cigarettes and inhalants showed the lowest age at initiation. We conducted logistic regressions on lifetime prevalence of inhalant use, and compared these models to other substances. In general, we found that attachment to parents. parents' drug use, and school attachment were strong predictors of lifetime use of marijuana, alcohol, and inhalants. However, while peer drug use was a strong predictor of marijuana and alcohol use, it was not a significant predictor of adolescents' use of inhalants. Our final set of analyses included inhalant use in regression models predicting other problem behaviors: these analyses demonstrated that inhalant use was a strong predictor of involvement in problem behavior. 相似文献
50.
Despite numerous measures of facets of the body image construct, no single assessment broadly measures a continuum of body image disturbance. Accordingly, this study developed the Body Image Disturbance Questionnaire (BIDQ), derived from the Body Dysmorphic Disorder Questionnaire. Participants were 220 college women and 75 college men who completed an online survey containing this new assessment and established measures of body image and psychosocial functioning. Results confirmed that the Body Image Disturbance Questionnaire was internally consistent and free of impression-management response bias. For both sexes, the measure converged appropriately with other body image indices (evaluation, affect, investment, and impact), was positively correlated with depression, social anxiety, and eating disturbance. Scores on this assessment also predicted psychosocial functioning above and beyond body dissatisfaction as a predictor. Greater body image disturbance was observed among women than men, among heavier than lighter women, and among White than African American women. Limitations and future research implications are discussed. 相似文献