Parallel functional subnetworks embedded in the macaque face patch system

During normal vision, our eyes provide the brain with a continuous stream of useful information about the world. How visually specialized areas of the cortex, such as face-selective patches, operate under natural modes of behavior is poorly understood. Here we report that, during the free viewing of videos, cohorts of face-selective neurons in the macaque cortex fractionate into distributed and parallel subnetworks that carry distinct information. We classified neurons into functional groups based on their video-driven coupling with fMRI time courses across the brain. Neurons from each group were distributed across multiple face patches but intermixed locally with other groups at each recording site. These findings challenge prevailing views about functional segregation in the cortex and underscore the importance of naturalistic paradigms for cognitive neuroscience.

A Development of Multi-Language Interactive Device using Artificial Intelligence Technology for Visual Impairment Person

<p class="0abstract">The issue of lacking reference books in braille in most public building is crucial, especially public places like libraries, museum and others. The visual impairment or blind people is not getting the information like we normal vision do. Therefore, a multi languages reading device for visually impaired is built and designed to overcome the limitation of reference books in public places. Some research regarding current product available is done to develop a better reading device. This reading device is an improvement from previous project which only focuses on single language which is not suitable for public places. This reading device will take a picture of the book using 5MP Pi camera, Google Vision API will extract the text, and Google Translation API will detect the language and translated to desired language based on push buttons input by user. Google Text-to-Speech will convert the text to speech and the device will read out aloud in through audio output like speaker or headphones. A few testings have been made to test the functionality and accuracy of the reading device. The testings are functionality, performance test and usability test. The reading device passed most of the testing and get a score of 91.7/100 which is an excellent (A) rating<strong>.</strong></p>

Study on Ocular Diseases in Ain Shams University New Medical Students and Its Value on Future Subspecialty

Purpose Our aim is to study ocular diseases in symptomless and symptomatic newly admitted medical students in the Faculty of Medicine, Ain Shams University Patients and Methods This cross-sectional clinical study was conducted in Faculty of Medicine Ain Shams University. The study included 304 new medical students of class 2015 and 2016 who were randomly selected upon admission to college on October 2015 and October 2016 and who agreed to participate in this study. All participants underwent a complete ophthalmologic evaluation including detailed history and unaided visual acuity, best corrected visual acuity, anterior and posterior segment examination and assessment of binocular vision by titmus test. Results 301 students (99.0%) have normal gross stereopsis and (1.0%) have no gross stereopsis using Titmus fly test. Fine stereopsis among studied group ranged from 0-9 (800-40 sec of arc) which was the ability to define the circles in titmus test but with mean of 7.29 ± 2.33(i.e. mean stereopsis was 60 sec of arc). Anisometropia was found in 32/304 (10.5%) of total population and 32/169 (18.9%) of total number students with refractive errors, 10 students were males and 22 students were females. Myopia was the commonest refractive error (51.90%). Conclusion Normal vision is integral to an individual understanding of his visual world, and those with visual defects can experience difficulties in everyday life. From these visual impairment problems are refractive errors, and abnormal binocular vision which if left uncorrected can affect performance of medical students.

Incremental Visual Occlusion During Split-Belt Treadmill Walking Has No Gradient Effect on Adaptation or Retention

Split-belt treadmills have become an increasingly popular means of quantifying ambulation adaptability. Multiple sensory feedback mechanisms, including vision, contribute to task execution and adaptation success. No studies have yet explored visual feedback effects on locomotor adaptability across a spectrum of available visual information. In this study, we sought to better understand the effects of visual information on locomotor adaptation and retention by directly comparing incremental levels of visual occlusion. Sixty healthy young adults completed a split-belt adaptation protocol, including a baseline, asymmetric walking condition (adapt), a symmetric walking condition (de-adapt), and another asymmetric walking condition (re-adapt). We randomly assigned participants into conditions with varied visual occlusion (i.e., complete and lower visual field occlusion, or normal vision). We captured kinematic data, and outcome measures included magnitude of asymmetry, spatial and temporal contributions to step length asymmetry, variability of the final adapted pattern, and magnitude of adaptation. We used repeated measures and four-way MANOVAs to examine the influence of visual occlusion and walking condition. Participants with complete, compared to lower visual field visual occlusion displayed less consistency in their walking pattern, evident via increased step length standard deviation ( p = .007, d = 0.89), and compared to normal vision groups ( p = .003 d = 0.81). We found no other group differences, indicating that varying levels of visual occlusion did not significantly affect locomotor adaptation or retention. This study offers insight into the role vision plays in locomotor adaptation and retention with clinical utility for improving variability in step control.

Investigating Visual Recognition of Color and Safe Driving in Color-Weak Drivers

This study examined the visual characteristics of drivers with color weakness to improve their safety while driving. Significantly affected by the traffic environment, drivers with color weakness are not able to recognize traffic lights rapidly and accurately, which endangers traffic safety. In the first part of the research, through a static visual recognition test of color vision using the orthogonal method, the study explored the influence of light intensity, visual recognition distance, and color weakness type on the perception of traffic light colors by participants with color weakness. In the second part, a dynamic visual recognition test of color vision was conducted through simulating the driving environment of urban roads. Eye movement indexes between participants with color weakness and those with normal vision were analyzed by means of different vehicle speeds and time periods. The results indicated that the type of color weakness was the dominant factor affecting visual recognition of traffic lights. The eye movements of participants with deuteranomaly were close to those of people with normal vision, whereas the eye movement index of those with protanomaly and dyserythrochloropsia were significantly different. Distraction, slower responses, and higher color recognition error rates for the traffic lights were major characteristics—all representing risks that increase at night. To reduce the probability of road traffic injury, the driving safety of people with color weakness should be addressed.

Alterations in Heart rate Variability in Blind Patients

Blindness affect the daily life activities and the causes and prevalence are different worldwide. This study aimed to investigate the pattern of the autonomic nervous system modulation on the heart in blind and normal vision subjects submitted acutely to low vision. Normal vision (NV) subjects (N = 32) and blind patients (N = 24) were submitted to HRV analysis during resting, intervention and recovery periods. Intervention consisted of handling objects, short walking, and cognitive activities performed with pedagogic games while using sleeping masks. No difference was observed in indexes in the time and frequency domain, and in the geometric indexes comparing blind and NV subjected to acute low vision during resting and recovery. Nevertheless, during intervention, RMSSD, pNN50, and SD1were found lower in blind than in NV subjects. Therefore, blind patients showed similar HRV at resting or upon possible stressful challenges compared to NV subjects acutely subjected to low vision, indicating absence of differences in the cardiovascular risk between groups. In addition, blind patients show a smaller reduction in parasympathetic modulation on the heart during possible stressful challenges than NV individuals submitted to low vision, which is likely an important physiological adaptation for an adequate function of the cardiovascular system in blindness.

Visual Adaptation to Scattering in Myopes

Myopes exhibit a larger capability of adaptation to defocus. Adaptation produces a boost in visual performance that can be characterized through different metrics. The ability of myopes to adapt to other sources of blur, such as diffusion, has not been studied so far. In this work, a group of 20 myopes with normal vision underwent high-contrast visual acuity (VA) measurements under different viewing conditions, wearing their refractive correction with or without a diffuser (Bangerter filter, BF). VA decreased immediately after wearing the BF of density 0.6, showing a significant relationship with the ocular refraction. After 40 minutes of binocular vision through the BF, a statistically significant increase (p = 0.02) in VA from 0.54 to 0.62 in decimal scale (from 0.3 to 0.2 logMAR) was obtained. No correlation with the refraction was observed. After removing the diffuser, VA returned to baseline. A control group (17 subjects) underwent the same experimental protocol but without diffuser filters. No significant changes in VA were found in this group. We describe a new type of contrast adaptation to blur in myopes caused by scattering, rather than by defocus. The effects of low scattering levels in vision might be relevant in the analysis of early stage of cataract, amblyopia treatments, and myopia understanding.

Longitudinal Rehabilitation of Binocular Function in Adolescent Intermittent Exotropia After Successful Corrective Surgery

PurposeTo study the longitudinal rehabilitation of binocular visual function in adolescent intermittent exotropia (IXT) after successful surgery and compare the results with those of a normal population. The role of binocular function in ocular alignment stability was also evaluated postoperatively.MethodsIn this prospective study, 30 adolescents with IXT successfully corrected after 1 month were followed for 12 months, and 30 children with normal vision were enrolled as controls. Stereopsis, the fusional vergence amplitude, sensory fusion, and accommodative flexibility were measured to assess binocular function at baseline and 6 and 12 months postoperatively. The controls were tested once when they were enrolled in the study.ResultsThe deviation was −32.00 ± 8.60 prism diopters (PD) at distance fixation and −36.0 ± 9.10 PD at near fixation preoperatively with an average correction of 28.53 ± 3.79 PD and 30.67 ± 1.34 PD at 1 month postoperatively. Distance stereoacuity and near stereoacuity improved from 1 to 12 months postoperatively (p = 0.025 and p = 0.041, respectively). Compared with the controls, the fusional convergence reserve at distance (p = 0.025) and near (p = 0.033) fixations and fusion reserve ratio at distance (p = 0.000) and near (p = 0.000) fixations remained subnormal, whereas sensory fusion (p = 0.237), distance stereopsis (p = 0.120), and the fusional divergence amplitude at a distance (p = 0.168) were normal. However, no significant correlations were found between binocular functions at 1 month postoperatively and the postoperative drift.ConclusionBinocular function significantly improved from before to after successful corrective surgery and continued to improve from 1 to 12 months postoperatively in adolescents with IXT. No significant correlations were found between binocular functions at 1 month postoperatively and ocular alignment stability.