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Blind football players use head movements to accurately identify sound location when trapping a ball. Accurate sound localization is likely important for motor learning of ball trapping in blind football. However, whether head movements affect the acquisition of ball-trapping skills remains unclear. Therefore, this study examined the effect of head movements on skill acquisition during ball trapping. Overall, 20 sighted male college students were recruited and assigned to one of the following two groups: the conventional training group, where they were instructed to move leftward and rightward to align their body with the ball’s trajectory, and the head-movement-focused group, where they were instructed to follow the ball with their faces until the ball touched their feet, in addition to the conventional training instructions. Both groups underwent a 2-day training for ball trapping according to the specific instructions. The head-movement-focused group showed a decrease in errors in ball trapping at near distances and with larger downward head rotations in the sagittal plane compared to the conventional training group, indicating that during the skill acquisition training for ball trapping, the sound source can be localized more accurately using larger head rotations toward the ball. These results may help beginner-level players acquire better precision in their movements while playing blind football.

Visual impairment poses considerable challenges to mobility and everyday tasks, frequently leading to a more sedentary lifestyle and reduced physical fitness levels. Therefore, this study investigated the effects of a tailored aquatic exercise protocol on muscle activation and strength in visually impaired individuals. Thirty women who were blind (mean age = 29.03 ± 2.20 years) were randomly assigned to an experimental (EX) group and a control (CO) group. The EX group participated in three weekly 60-minute aquatic sessions, while the CO group maintained regular activities. Electromyography (EMG) activation and onset time were measured in the tibialis anterior, gastrocnemius medialis, rectus femoris, and biceps femoris. Muscle strength was also assessed in the ankle dorsiflexors and plantarflexors, as well as the knee flexors and extensors. The EX group showed increased EMG activation for the tibialis anterior, gastrocnemius medialis, rectus femoris, and biceps femoris in both anterior-posterior (2.23 MVIC%, 95% CI: 1.13 to 3.34, p < 0.001) and posterior-anterior directions (2.35 MVIC%, 95% CI: 1.80 to 2.91, p < 0.001) compared to CO group. Onset time decreased significantly in the EX group relative to CO group (anterior-posterior: -108.07 ms, 95% CI: -117.23 to -98.89, p < 0.001; posterior-anterior: -98.72 ms, 95% CI: -106.54 to -90.90, p < 0.001). Muscle strength significantly increased in the EX group compared to the CO group, with greater strength in ankle dorsiflexors (4.42 N/kg, 95% CI: 3.42 to 5.42, p < 0.001) and knee extensors (2.72 N/kg, 95% CI: 1.04 to 4.40, p < 0.001). The aquatic exercise program improved neuromuscular function and strength in women with visual impairments, supporting its use in rehabilitation. IRCT2017022132705N1.

Persons with visual impairment (VI) are at greater risk for falls due to irreparable damage to visual sensory input contributing to balance. Targeted training may significantly improve postural stability by strengthening the remaining sensory systems. Here, we evaluate the Ashtanga-based Yoga Therapy (AYT) program as a multi-sensory behavioral intervention to develop postural stability in VI. A randomized, waitlist-controlled, single-blind clinical trial. The trial was conducted between October 2012 and December 2013. Twenty-one legally blind participants were randomized to an 8-week AYT program (n = 11, mean (SD) age = 55(17)) or waitlist control (n=10, mean (SD) age = 55(10)). AYT subjects convened for one group session at a local yoga studio with an instructor and two individual home-based practice sessions per week for a total of 8 weeks. Subjects completed outcome measures at baseline and post-8 weeks of AYT. The primary outcome, absolute Center of Pressure (COP), was derived from the Wii Balance Board (WBB), a standalone posturography device, in 4 sensory conditions: firm surface, eyes open (EO); firm surface, eyes closed (EC); foam surface, EO; and foam surface, EC. Stabilization Indices (SI) were computed from COP measures to determine the relative visual (SIfirm, SIfoam), somatosensory (SIEO, SIEC) and vestibular (SIV, i.e., FoamEC vs. FirmEO) contributions to balance. This study was not powered to detect between group differences, so significance of pre-post changes was assessed by paired samples t-tests within each group. Groups were equivalent at baseline (all p > 0.05). In the AYT group, absolute COP significantly increased in the FoamEO (t(8) = -3.66, p = 0.01) and FoamEC (t(8) = -3.90, p = 0.01) conditions. Relative somatosensory SIEO (t(8) = -2.42, p = 0.04) and SIEC (t(8) = -3.96, p = 0.01), and vestibular SIV (t(8) = -2.47, p = 0.04) contributions to balance increased significantly. As expected, no significant changes from EO to EC conditions were found indicating an absence of visual dependency in VI. No significant pre-post changes were observed in the control group (all p > 0.05). These preliminary results establish the potential for AYT training to develop the remaining somatosensory and vestibular responses used to optimize postural stability in a VI population. www.ClinicalTrials.gov NCT01366677.

Background The Argus® II retinal prosthesis system has entered mainstream treatment for patients blind from Retinitis Pigmentosa (RP). We set out to evaluate the use of this system by blind subjects to achieve object localisation and prehension in 3-dimensional space. Methods This is a single-centre, prospective, internally-controlled case series involving 5 blind RP subjects who received the Argus® II implant. The subjects were instructed to visually locate, reach and grasp (i.e. prehension) a small white cuboid object placed at random locations on a black worktop. A flashing LED beacon was attached to the reaching index finger (as a finger marker) to assess the effect of enhanced finger visualisation on performance. Tasks were performed with the prosthesis switched “on” or “off” and with the finger marker switched “on” or “off”. Forty-eight trials were performed per subject. Trajectory of each subject’s hand movement during the task was recorded by a 3D motion-capture unit (Qualysis®, see supplementary video ) and analysed using a MATLAB script. Result Percentage of successful prehension±standard deviation was: 71.3 ± 27.1 % with prosthesis on and finger marker on; 77.5 ± 24.5 % with prosthesis on and finger marker off; 0.0 ± 0.0 % with prosthesis off and finger marker on, and 0.00 ± 0.00 % with prosthesis off and finger marker off. The finger marker did not have a significant effect on performance ( P =  0.546 and 1, Wilcoxon Signed Rank test, with prosthesis on and off respectively). With prosthesis off, none of the subjects were able to visually locate the target object and no initiation of prehension was attempted. With prosthesis on, prehension was initiated on 82.5 % (range 59–100 %) of the trials with 89.0 % (range 66.7–100 %) achieving successful prehension. Conclusion Argus® II subjects were able to achieve object localisation and prehension better with their prosthesis switched on than off.

Background People with visual impairments can experience numerous challenges navigating unfamiliar environments. Systems that operate as prenavigation tools can assist such individuals. This mixed‐methods study examined the effectiveness of an interactive audio‐tactile map tool on the process of cognitive mapping and recall, among people who were blind or had visual impairments. The tool was developed with the involvement of visually impaired individuals who additionally provided further feedback throughout this research. Methods A mixed‐methods experimental design was employed. Fourteen participants were allocated to either an experimental group who were exposed to an audio‐tactile map, or a control group exposed to a verbally annotated tactile map. After five minutes’ exposure, multiple‐choice questions examined participants’ recall of the spatial and navigational content. Subsequent semi‐structured interviews were conducted to examine their views surrounding the study and the product. Results The experimental condition had significantly better overall recall than the control group and higher average scores in all four areas examined by the questions. The interviews suggested that the interactive component offered individuals the freedom to learn the map in several ways and did not restrict them to a sequential and linear approach to learning. Conclusion Assistive technology can reduce challenges faced by people with visual impairments, and the flexible learning approach offered by the audio‐tactile map may be of particular value. Future researchers and assistive technology developers may wish to explore this further. People with visual impairments can experience numerous challenges navigating unfamiliar environments. This mixed‐methods study examined the effectiveness of an interactive audio‐tactile map for the process of cognitive mapping and recall among people who were blind or had visual impairments. The audio‐tactile map condition had significantly better overall recall than the control group. The interviews suggested that the interactive component offered individuals the freedom to learn the map in several ways and did not restrict them to a sequential and linear approach to learning.

BackgroundThis study aimed to assess the prevalence and causes of vision loss in sub-Saharan Africa (SSA) in 2015, compared with prior years, and to estimate expected values for 2020.MethodsA systematic review and meta-analysis assessed the prevalence of blindness (presenting distance visual acuity <3/60 in the better eye), moderate and severe vision impairment (MSVI; presenting distance visual acuity <6/18 but ≥3/60) and mild vision impairment (MVI; presenting distance visual acuity <6/12 and ≥6/18), and also near vision impairment (

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