The findings indicate that visual acuity assessment in Chinese readers is complicated by the spatial complexity of Chinese characters, but the fact that the Snellen E, which is the current national standard of acuity measurement in China, and Chinese characters showed similar dependence on optical defocus may indicate a potentially valid way to infer functional vision in Chinese readers with Snellen E acuity.

Written Chinese is distinct from alphabetic languages because of its enormous number of characters with a great range of spatial complexities (stroke numbers). In this study we investigated the impact of spatial complexity on legibility of Chinese characters as well as associated crowding in peripheral vision. Our results showed that for isolated characters, threshold sizes of complex characters increased faster with retinal eccentricity than did those of simple characters, suggesting possible "within-character" crowding among parts of complex Chinese characters. However, such "within-character" crowding was rendered negligible by strong "between-character" crowding introduced by flankers. When the target and flankers belonged to different complexity groups, the intensity and extent of crowding were greatly reduced, which could be explained by top-down influences as well as lower-level mechanisms. We suggest that crowding can be attributed to multiple mechanisms at different levels of visual processing.

No abstract

Patients with a central scotoma usually use a preferred retinal locus (PRL) consistently in daily activities. The selection process and time course of the PRL development are not well understood. We used a gaze-contingent display to simulate an isotropic central scotoma in normal subjects while they were practicing a difficult visual search task. As compared to foveal search, initial exposure to the simulated scotoma resulted in prolonged search reaction time, many more fixations and unorganized eye movements during search. By the end of a 1782-trial training with the simulated scotoma, the search performance improved to within 25% of normal foveal search. Accompanying the performance improvement, there were also fewer fixations, fewer repeated fixations in the same area of the search stimulus and a clear tendency of using one area near the border of the scotoma to identify the search target. The results were discussed in relation to natural development of PRL in central scotoma patients and potential visual training protocols to facilitate PRL development.

A two-part latent growth mixture model was implemented in order to examine heterogeneity in the growth of sexual harassment (SH) victimization in college and university students, and the extent to which SH class membership explains substance use and mental health outcomes for certain groups of students. Demographic risk factors, mental health, and substance use were examined as they related to chronically experienced SH victimization. Incoming freshmen students (N = 2855; 58% female; 54% White) completed a survey at five time points. In addition to self-reporting gender, race, and sexual orientation, students completed measures of sexual harassment, anxiety, depression, binge drinking, and marijuana use. Overall, self-reported SH declined upon college entry, although levels rebounded by the third year of college. Results also supported a two-class solution (Infrequent and Chronic) for SH victimization. Being female, White, and a sexual minority were linked to being classified into the Chronic (relative to the Infrequent) SH class. In turn, Chronic SH class membership predicted greater anxiety, depression, and substance use, supporting a mediational model.

Purpose-The purpose of this study was to investigate the effect of residential blind rehabilitation on patients' vision targeted health-related quality of life (HRQOL) and general physical and mental function.Methods-The National Eye Institute 25-item Visual Function Questionnaire (NEI VFQ) plus appendix questions, the 12 item Short-Form Health Survey (SF-12), Hope Scale and Coopersmith self-esteem inventory were administered to 206 legally blind veterans prior to their entering a residential (in-patient) blind rehabilitation program and again to 185 and 176 of the original cohort at two and six months after completion of the rehabilitation program, respectively. Data on visual acuity, visual field extent, contrast sensitivity and scanning ability were also collected. The duration of the in-patient rehabilitation programs ranged from 11-109 days. Questionnaire scores were compared pre-rehabilitation and post-rehabilitation.Results-Following rehabilitation there was a significant improvement in nine of eleven NEI VFQ subscales and in a composite score at both 2-and 6-month post-rehab intervals. Mental health (SF-12) and self esteem also improved significantly although physical health ratings declined over the course of the study (approximately 10 months).Conclusions-Residential blind rehabilitation appears to improve patients' self-reported visiontargeted HRQOL, self-esteem, and mental health aspects of generic HRQOL.

No abstract

Feature search performance was measured in visually impaired (VI) and age-matched controls with normal vision (NV). All VI subjects were legally blind. The task was to search for a 2 degrees x 2 degrees square target among smaller 1 degrees x1 degrees distracters. Targets and distracters were white and presented on a dark background that subtended 69 degrees by 58 degrees . Three field-sizes (10 degrees , 20 degrees , and 40 degrees ) and three set sizes (8-, 16-, and 32-items) were tested. The VI subjects searched more slowly than the NV subjects, but the reaction time of both groups of subjects did not rise with increasing number of items. The latter is consistent with a parallel search. Both groups searched more slowly when field-size increased, but the VI group was affected more by the increase than the NV group.