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211.
We used a visual-search method to investigate the role of shadows in the rapid discrimination of scene properties. Targets and distractors were light or dark 2-D crescents of identical shape and size, on a mid-grey background. From the dark stimuli, illusory 3-D shapes can be created by blurring one arc of the crescent. If the inner arc is blurred, the stimulus is perceived as a curved surface with attached shadow. If the outer arc is blurred, the stimulus is perceived as a flat surface casting a shadow. In a series of five experiments, we used this simple stimulus to map out the shadow properties that the human visual system can rapidly detect and discriminate. To subtract out 2-D image factors, we compared search performance for dark-shadow stimuli with performance for light-shadow stimuli which generally do not elicit strong 3-D percepts. We found that the human visual system is capable of rapid discrimination based upon a number of different shadow properties, including the type of the shadow (cast or attached), the direction of the shadow, and the displacement of the shadow. While it is clear that shadows are not simply discounted in rapid search, it is unclear at this stage whether rapid discrimination is acting upon shadows per se or upon representations of 3-D object shape and position elicited by perceived shadows. 相似文献
212.
Past research has repeatedly documented the close relationship between visual attention and awareness. Most recently, research exploring change blindness, inattentional blindness, repetition blindness, and the attentional blink has converged on the conclusion that attention to one aspect of a scene or event may lead to a highly circumscribed awareness of only the specific information attended, while other information, even that which is spatially or temporally nearby can go completely unnoticed. In the present report, we extend these observations to the dynamic allocation of attention during a well-structured meaningful event. In two experiments, subjects viewed brief videos of simple events and were told to pay close attention to them. During the events, an unexpected disruption consisting of a brief low spatial frequency motion field occurred. Despite intensive questioning and opportunities for recognition, the majority of subjects reported no awareness of 200, 400, or 600 ms disruptions. In a second experiment, blank-screen disruptions were added, and these resulted in no increase in detection. We conclude that visual attention may result in far more transitory awareness of visual information than previously appreciated. 相似文献
213.
Topolski TD Edwards TC Patrick DL Varley P Way ME Buesching DP 《Journal of attention disorders》2004,7(3):163-173
Most psychosocial research on attention-deficit/hyperactivity disorder (ADHD) has focused on deficits in school, family, or behavioral functioning without incorporating perceived quality of life (QoL) or the adolescents' perspective. The Youth Quality of Life Instrument--Research Version (YQOL-R), was used to assess self-perceived QoL in a community sample of adolescents aged 11-18 years. Fifty-five adolescent males with a clinical diagnosis of ADHD were compared to a group of 107 adolescents with no chronic conditions (NCC) and a group of 52 adolescents with mobility impairments (MI). The adolescents with ADHD reported significantly lower perceived QoL scores, particularly in the Self and Relationship domains, than the NCC group. Their scores were similar to those from the group with MI, a group previously shown to have a substandard QoL. Interventions to improve self-esteem and social interactions might use QoL outcomes in evaluating effectiveness. 相似文献
214.
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
215.
216.
In this study, the authors confirm and expand previous findings (M. Anastasi, R. G. Sawyer, & P. J. Pinciaro, 1999; J. E. Lewis & R. M. Malow, 1997) concerning college students' knowledge and perceptions about HIV/AIDS. Although students are knowledgeable about HIV/AIDS, they have little personal concern about becoming infected and do not take appropriate safe sex precautions. Findings of the present study show that gender, ethnic background, and knowing someone infected by HIV/AIDS influence students' level of concern about infection. In addition, older students and those who know someone infected by HIV/AIDS are more likely to have been tested. Results are compared with national surveys of other age groups, and the authors suggest specific intervention strategies for college students. 相似文献
217.
Erik H. Erikson's life cycle schema consists of eight stages. Three are located in infancy and early childhood (ages 1–5), one in childhood (5–12), one in adolescence, and three in adulthood. This essay proposes a relocation of the stages in terms of decades. The eight psychosocial crises in Erikson's model are retained, but each crisis and its resolution is the central theme of a decade of life. This relocation of Erikson's stages orients the life cycle schema more toward adulthood than to early childhood, as six of the stages now occur in the adult years. It also reflects Erikson's theoretical shift in emphasis from the ego to the sense of I in his later writings. A proposal for how the ninth and tenth decades fit into the schema is also offered. 相似文献
218.
Dougherty DM Mathias CW Marsh DM Papageorgiou TD Swann AC Moeller FG 《Suicide & life-threatening behavior》2004,34(4):374-385
The purpose of this study was to examine the relationship between laboratory behavioral measured impulsivity (using the Immediate and Delayed Memory Tasks) and suicidal attempt histories. Three groups of adults were recruited, those with either: no previous suicide attempts (Control, n = 20), only a single suicide attempt (Single, n = 20), or multiple suicidal attempts (Multiple, n = 10). As hypothesized, impulsive responses increased with the number of suicide attempts (Control < Single < Multiple). This study helps to demonstrate how laboratory behavioral measures of impulsivity can be used to discriminate groups based on suicidal histories among samples not currently exhibiting significant suicidal behaviors. 相似文献
219.
Adult attachment and patterns of extradyadic involvement 总被引:2,自引:0,他引:2
Relationships between patterns of extradyadic involvement (EDI) and adult attachment were examined separately with undergraduates and community adults reporting prior EDI. Those with fearful or preoccupied styles reported more intimacy motivations for EDI, and undergraduates with these styles also reported more self-esteem motivations. Conversely, those with a dismissive style reported more autonomy motivations for EDI. Those with a fearful attachment style reported ambivalence about intimacy in the EDI. Fearful and preoccupied undergraduates and community males reported a more obsessive extradyadic relationship. However, dismissive individuals did not report more casual EDI. Gender effects also emerged, with females reporting more intimacy motivations than males, and undergraduate males reporting more casual EDI than undergraduate females. In the undergraduate sample, dismissive males had the most extradyadic partners over the prior 2 years relative to all other groups, and preoccupied females reported more partners than secure females. Clinical implications of these findings are discussed. 相似文献
220.
The personality, psychopathological, and demographic differences between 330 alcoholic men referred for behavioral problems and 104 alcoholic men referred for medical problems were examined. The Minnesota Multiphasic Personality Inventory-2 indicated that those referred for behavioral problems showed more antisocial characteristics, while those referred for medical reasons had more subjective distress, were more highly introverted, and showed greater somatic preoccupation. Hispanic alcoholic men had a significantly higher proportion of medical referrals than Caucasian and African-American alcoholic men. 相似文献