Balance, gait, and navigation performance are related to physical exercise in blind and visually impaired children and adolescents

Balance Level and Fundamental Motor Skills of Youth with Visual Impairments: Pilot Study

Background: Visual impairment significantly affects balance and motor skills in children, often leading to postural instability and locomotor difficulties, thereby affecting lifestyle and general health. The aim of this study was to assess balance level and fundamental motor skills in the locomotion of youth with regard to their level of visual impairment. Methods: The pilot study included 25 physically active young people with visual impairments, divided into three groups (B1, B2, B3) based on the severity of impairment. Balance was assessed using the AMTI AccuSway platform, both with eyes open and eyes closed. Locomotor skills were evaluated using the TGMD-3. Statistical analysis involved Kruskal-Wallis, ANOVA, and correlation tests. Results: Significant differences in balance were found between the B1 and B2 groups, with poorer balance in individuals with more severe visual impairments, particularly in static conditions. No significant differences in locomotor skills were observed between groups. However, girls performed better in balance tests, particularly with eyes closed. A positive correlation was found between balance and locomotor skills in the B2 and B3 groups. Conclusions: Visual impairment negatively impacts balance, particularly in individuals with more severe impairments. However, no significant differences were found in locomotor skills between the groups. Regular physical activity supports motor development. Targeted interventions are necessary to improve balance and locomotor skills, especially in children with more severe visual impairments.

Postural control depends on early visual experience

The present study investigated the role of early visual experience in the development of postural control (balance) and locomotion (gait). In a cross-sectional design, balance and gait were assessed in 59 participants (ages 7-43 years) with a history of (a) transient congenital blindness, (b) transient late-onset blindness, (c) permanent congenitally blindness, or (d) permanent late-onset blindness, as well as in normally sighted controls. Cataract-reversal participants who experienced a transient phase of blindness and gained sight through cataract removal surgery showed worse balance performance compared with sighted controls even when tested with eyes closed. Individuals with reversed congenital cataracts performed worse than individuals with reversed developmental (late emerging) cataracts. Balance performance in congenitally cataract-reversal participants when tested with eyes closed was not significantly different from that in permanently blind participants. In contrast, their gait parameters did not differ significantly from those of sighted controls. The present findings highlight both the need for visual calibration of proprioceptive and vestibular systems and the crossmodal adaptability of locomotor functions.

Adapted Training to Boost Upper Body Sensorimotor Control and Daily Living Functionality in Visually Impaired Baseball Players

Background and Objectives: Vision significantly contributes to postural control, balance, coordination, and body kinematics, thus deeply influencing everyday functionality. Sight-impaired subjects often show upper body anatomofunctional and kinetic chain alterations negatively impacting daily living efficiency and autonomy. The present study aimed to investigate and train, for the first time, upper body sensorimotor control in an Italian blind baseball team to boost global and segmental functionality while contemporarily prevent injuries. Materials and Methods: The whole team underwent a validated test battery using both quantitative traditional tools, such as goniometric active range of motion and muscular/functional tests, and an innovative biofeedback-based device, a Libra proprioceptive board. Consequently, a 6-week adapted training protocol was designed and leaded to improve sensorimotor control and, hence, counteract disability-related deficits and sport-specific overuse syndromes. Results: Statistically significant improvements were observed in all the investigated parameters. Noteworthy, an overall boost of global and segmental stability was detected through an orthostatic dynamic balance enhancement during the Y Balance test (p = 0.01) and trunk multiplanar control improvement on the Libra board (p = 0.01). Concurrently, the comparison of baseline vs. post-intervention outcomes revealed a consistent increase in upper body mobility (p < 0.05 for all the assessed districts), core recruitment (p = 0.01 for all the administered functional tests), and proprioceptive postural control (p = 0.01 for the Libra board validated test). Conclusions: Our findings suggest that a tailored sensorimotor training, conceived and led by an adapted physical activity kinesiologist, may effectively improve upper body functional prerequisites and global proprioceptive control, thus potentially promoting autonomy, quality of life, and physical activity/sport practice adherence in visually impaired individuals.

A feasibility study investigating cortical hemodynamic changes during infinity walk with fNIRS

This study seeks to explore the correlation between cortical activation and the Infinity Walk pattern, examining how the influence of foot overpronation and footwear may impact motor control. Functional near-infrared spectroscopy (fNIRS), a portable and user-friendly neuroimaging technique, was used to measure hemodynamical changes in six individuals with non-critical pronation degrees. Participants perform the Infinity Walk under various footwear conditions while wearing an fNIRS portable imaging device. Results indicate a consistent hemodynamic pattern in both hemispheres during the Infinity Walk, with no significant differences observed across subjects and footwear conditions in the prefrontal cortex (PFC), pre-motor area, the supplementary motor cortex (PMA & SMC), the primary motor cortex (PMC), and Wernicke's area (WA). The impact of pronation and footwear on motor control remains inconclusive due to inconsistent hemodynamic patterns. Notably, the activation patterns in Broca's area (BA) and the temporal gyrus (TG) differ significantly from other brain regions. The balanced hemodynamic responses in the bilateral hemispheres may be attributed to the Infinity Walk's inherent walking pattern. These findings indicate a need for further investigation into the Infinity Walk to examine the similarities and distinctions in activation patterns within specific brain regions. Additionally, the impact of pronation necessitates more substantial experimental research to establish a correlation between pronation and cortical hemodynamics.

How path integration abilities of blind people change in different exploration conditions

For animals to locate resources and stay safe, navigation is an essential cognitive skill. Blind people use different navigational strategies to encode the environment. Path integration significantly influences spatial navigation, which is the ongoing update of position and orientation during self-motion. This study examines two separate things: (i) how guided and non-guided strategies affect blind individuals in encoding and mentally representing a trajectory and (ii) the sensory preferences for potential navigational aids through questionnaire-based research. This study first highlights the significant role that the absence of vision plays in understanding body centered and proprioceptive cues. Furthermore, it also underscores the urgent need to develop navigation-assistive technologies customized to meet the specific needs of users.

Physical activity and sport practice to improve balance control of visually impaired individuals: a narrative review with future perspectives

Visual disability negatively impacts balance, everyday self-efficacy, and mobility and often leads affected subjects to perceive physical exercise as a burdensome challenge thus discouraging them from practicing. Despite the well-proven benefits of regular physical activity in visually impaired people, especially addressing postural control, there are no specific guidelines and most of the available literature seems to be flawed by critical issues. Given the wide heterogeneity and the multidimensional needs of this population, a more realistic and target-specific perspective is needed in order to properly investigate and promote exercise practice and adherence for balance improvement. On this basis, through a critical overview of the recent literature, the present article aimed to enrich the current knowledge about this topic by providing innovative suggestions, both practical and methodological, and specifically deepening the disability-related deficits and peculiarities of different age ranges. Moreover, since a multidisciplinary approach is advisable when designing and leading exercise protocols tailored to visually impaired individuals, such innovative hints also highlighted the central role of the adapted physical activity specialist, hence contributing to foster its official professional recognition and involvement in this field.

Reactive Agility and Pitching Performance Improvement in Visually Impaired Competitive Italian Baseball Players: An Innovative Training and Evaluation Proposal

Visual input significantly affects kinesthesis skills and, hence, visually impaired individuals show less developed sensorimotor control, especially in an unfamiliar outdoor environment. Regular blind baseball practice can counteract such a deficit but, given the complex kinetic chain model required, a targeted workout proposal is needed to improve the main athletic gesture performance. On these premises, we investigated, for the first time, the running and pitching performance of a competitive Italian blind baseball team through quantitative tools and parameters such as Libra Easytech sensorized proprioceptive board, goniometric active range of motion, chronometric speed, and pitching linear length. Moreover, the perceived physical exertion was assessed by the Borg CR10 scale. Consequently, an adapted athletic training protocol was designed and tested on the field during the competitive season, with the aim to strengthen sport specific-gesture coordination and efficacy as well as to prevent injuries. Quantitative assessments showed an improvement in ankle stability index, bilateral upper limb and hip mobility, reactive agility, running braking phase control during second base approaching, and auditory target-related pitching accuracy along with a decrease in perceived physical exertion. This protocol might therefore represent an effective and easily reproducible training and evaluation approach to tailor management of visually impaired baseball players, and safely improve their athletic performance under the supervision of an adapted exercise specialist.

Design of Audio-Augmented-Reality-Based O&M Orientation Training for Visually Impaired Children

Orientation and Mobility training (O&M) is a specific program that teaches people with vision loss to orient themselves and travel safely within certain contexts. State-of-the-art research reveals that people with vision loss expect high-quality O&M training, especially at early ages, but the conventional O&M training methods involve tedious programs and require a high participation of professional trainers. However, there is an insufficient number of excellent trainers. In this work, we first interpret and discuss the relevant research in recent years. Then, we discuss the questionnaires and interviews we conducted with visually impaired people. On the basis of field investigation and related research, we propose the design of a training solution for children to operate and maintain direction based on audio augmented reality. We discuss how, within the perceptible scene created by EasyAR's map-aware framework, we created an AR audio source tracing training that simulates a social scene to strengthen the audiometric identification of the subjects, and then to verify the efficiency and feasibility of this scheme, we implemented the application prototype with the required hardware and software and conducted the subsequential experiments with blindfolded children. We confirm the high usability of the designed approach by analyzing the results of the pilot study. Compared with other orientation training studies, the method we propose makes the whole training process flexible and entertaining. At the same time, this training process does not involve excessive economic costs or require professional skills training, allowing users to undergo training at home or on the sports ground rather than having to go to rehabilitation sites or specified schools. Furthermore, according to the feedback from the experiments, the approach is promising in regard to gamification.

Neural substrates of spatial processing and navigation in blindness: An activation likelihood estimation meta-analysis

Even though vision is considered the best suited sensory modality to acquire spatial information, blind individuals can form spatial representations to navigate and orient themselves efficiently in space. Consequently, many studies support the amodality hypothesis of spatial representations since sensory modalities other than vision contribute to the formation of spatial representations, independently of visual experience and imagery. However, given the high variability in abilities and deficits observed in blind populations, a clear consensus about the neural representations of space has yet to be established. To this end, we performed a meta-analysis of the literature on the neural correlates of spatial processing and navigation via sensory modalities other than vision, like touch and audition, in individuals with early and late onset blindness. An activation likelihood estimation (ALE) analysis of the neuroimaging literature revealed that early blind individuals and sighted controls activate the same neural networks in the processing of non-visual spatial information and navigation, including the posterior parietal cortex, frontal eye fields, insula, and the hippocampal complex. Furthermore, blind individuals also recruit primary and associative occipital areas involved in visuo-spatial processing via cross-modal plasticity mechanisms. The scarcity of studies involving late blind individuals did not allow us to establish a clear consensus about the neural substrates of spatial representations in this specific population. In conclusion, the results of our analysis on neuroimaging studies involving early blind individuals support the amodality hypothesis of spatial representations.

Reliability of the triangle completion test in the real-world and in virtual reality

Background

The triangle completion test has been used to assess egocentric wayfinding for decades, yet there is little information on its reliability. We developed a virtual reality (VR) based test and investigated whether either test of spatial navigation was reliable.

Objective

To examine test-retest reliability of the real-world and VR triangle completion tests. A secondary objective was to examine the usability of the VR based test.

Materials and methods

Thirty healthy adults aged 18–45 years were recruited to this block randomized study. Participants completed two sessions of triangle completion tests in the real-world and VR on the same day with a break between sessions.

Results

In both test versions distance from the endpoint and angle of deviation showed poor test-retest reliability (r < 0.5). Distance traveled had moderate reliability in both the real-world and VR tests (r = 0.55 95% CI [0.23, 0.76]; r = 0.66 95% CI [0.4, 0.83, respectively]). The VR triangle test showed poor correlation with the real-world test.

Conclusion

The triangle completion test has poor test-retest reliability and demonstrates poor concurrent validity between the real-world and VR. Nevertheless, it was feasible to translate a real-world test of spatial navigation into VR. VR provides opportunities for development of clinically relevant spatial navigation tests in the future.

Survey on Psychological Well-Being and Quality of Life in Visually Impaired Individuals: Dancesport vs. Other Sound Input-Based Sports

Sport practice has the widely demonstrated potential of promoting well-being and physical/mental health, especially in disabled individuals. Nowadays, visually impaired people can participate in several sports commonly adapted and played substituting visual input with auditory or tactile ones. By integrating movement and music, dance can simultaneously promote physical and emotional involvement and enhances vicarious sense recruitment. On these premises, we performed a survey to assess the psychological well-being (PWB) and quality of life (QoL) in visually impaired athletes, comparing dancesport vs other sound input-based sports. Twenty-one visually impaired dancers and twenty-seven visually impaired athletes practicing adapted baseball, showdown, blind futsal, or blind tennis completed a structured self-report survey including the Italian version of PWB-18 scale and the Short Form-12 (SF-12) questionnaire. Dancers reported significantly higher scores in PWB-18 autonomy, environmental mastery, and self-acceptance along with a higher PWB total score than the other athlete group. Similarly, the SF-12 questionnaire results demonstrated significantly higher scores in both physical and mental QoL of visually impaired dancers compared with other athletes. In conclusion, our findings suggest that, given its peculiarities, the practice of dancesport may have a stronger positive impact on PWB and QoL of visually impaired individuals than other sound input-based sports.

Are Gait Biomechanics Related to Physical Activity Engagement? An Examination of Adolescents with ASD

PURPOSE

Adolescents with autism spectrum disorder (ASD) rarely meet physical activity (PA) guidelines, thus not reaping associated health benefits. Although many barriers exist, abnormal or inefficient gait biomechanics could negatively impact engagement in PA. This study has two purposes: first, to compare total body mechanical work between adolescents with ASD and neurotypical age, sex, and body mass index matched controls, and second to determine whether gait biomechanics are significantly related to engagement in PA.

METHODS

Twenty-five adolescents (age 13-18 years) with ASD and seventeen neurotypical controls (eight with ASD had no match) participated in the study. Three-dimensional motion capture and force platforms were used to record and analyze gait biomechanics at self-selected speeds and a standardized 1.3 m/s. Total body mechanical work (sum of joint works across lower extremity, low back, torso, and shoulders) was compared between groups (n = 17 for each) and speeds using a mixed model analysis of variance. Average daily light (LPA), moderate to vigorous (MVPA), and total PA was recorded for the entire dataset with ASD using triaxial accelerometers worn for one week. Regression analyses were performed between work, stride time variability, speed, and stride length with each PA variable.

RESULTS

Adolescents with ASD generated 9% more work compared to the controls (p=0.016). Speed and stride length were significant regressors of LPA, MVPA, and total PA, explaining greater than 0.20 variance (p<0.02 for all regressions).

CONCLUSION

Although adolescents with ASD walked with significantly greater work, the complex full-body variable is not significantly related to engagement in PA. In agreement with research spanning multiple populations and ages, speed and stride length are indicative of PA engagement in adolescents with ASD.

Anxiety and Motion Sickness Susceptibility May Influence the Ability to Update Orientation in the Horizontal Plane of Healthy Subjects

Few studies have evaluated the influence of idiosyncrasies that may influence the judgment of space-time orientation after passive motion. We designed a study to assess the influence of anxiety/depression (which may distort time perception), motion sickness susceptibility (which has been related to vestibular function, disorientation, and to the velocity storage mechanism), and personal habits on the ability to update orientation, after passive rotations in the horizontal plane. Eighty-one healthy adults (22–64 years old) accepted to participate. After they completed an in-house general health/habits questionnaire, the short Motion Sickness Susceptibility Questionnaire, the Hospital Anxiety and Depression Scale (HADS), the Pittsburgh Sleep Quality Index, and the short International Physical Activity Questionnaire, they were exposed to 10 manually driven whole-body rotations (45°, 90°, or 135°), in a square room, with distinctive features on the walls, while seated in the normal upright position, unrestrained, with noise-attenuating headphones and blindfolded. After each rotation, they were asked to report which wall or corner they were facing. To calculate the error of estimation of orientation, the perceived rotation was subtracted from the actual rotation. Multivariate analysis showed that the estimation error of the first rotation was strongly related to the results of the orientation test. The magnitude and the frequency of estimation errors of orientation were independently related to HADS anxiety sub-score and to adult motion sickness susceptibility, with no influence of age, but a contribution from the interaction of the use of spectacles, the quality of sleep and sex. The results suggest that idiosyncrasies may contribute to the space-time estimation of passive self-motion, with influence from emotional traits, adult motion sickness susceptibility, experience, and possibly sleep quality.

Coordination variability during running in adolescents with autism spectrum disorder

LAY ABSTRACT

Walking and running are popular forms of physical activity that involve the whole body (pelvis/legs and arms/torso) and are coordinated by the neuromuscular system, generally without much conscious effort. However, autistic persons tend not to engage in sufficient amounts of these activities to enjoy their health benefits. Recent reports indicate that autistic individuals tend to experience altered coordination patterns and increased variability during walking tasks when compared to non-autistic controls. Greater stride-to-stride coordination variability, when the task has not changed (i.e. walking at same speed and on same surface), is likely indicative of motor control issues and is more metabolically wasteful. To date, although, research examining running is unavailable in any form for this population. This study aimed to determine if coordination variability during running differs between autistic adolescents and age, sex, and body mass index matched non-autistic controls. This study found that increased variability exists throughout the many different areas of the body (foot-leg, left/right thighs, and opposite arm-opposite thigh) for autistic adolescents compared to controls. Along with previous research, these findings indicate autistic persons exhibit motor control issues across both forms of locomotion (walking and running) and at multiple speeds. These findings highlight issues with motor control that can be addressed by therapeutic/rehabilitative programming. Reducing coordination variability, inherently lessening metabolic inefficiency, may be an important step toward encouraging autistic youth to engage in sufficient physical activity (i.e. running) to enjoy physiological and psychological benefits.

Measuring Gait Stability in People with Multiple Sclerosis Using Different Sensor Locations and Time Scales

The evaluation of local divergence exponent (LDE) has been proposed as a common gait stability measure in people with multiple sclerosis (PwMS). However, differences in methods of determining LDE may lead to different results. Therefore, the purpose of the current study was to determine the effect of different sensor locations and LDE measures on the sensitivity to discriminate PwMS. To accomplish this, 86 PwMS and 30 healthy participants were instructed to complete a six-minute walk wearing inertial sensors attached to the foot, trunk and lumbar spine. Due to possible fatigue effects, the LDE short (~50% of stride) and very short (~5% of stride) were calculated for the remaining first, middle and last 30 strides. The effect of group (PwMS vs. healthy participants) and time (begin, mid, end) and the effect of Expanded Disability Status Scale (EDSS) and time were assessed with linear random intercepts models. We found that perturbations seem to be better compensated in healthy participants on a longer time scale based on trunk movements and on a shorter time scale (almost instantaneously) according to the foot kinematics. Therefore, we suggest to consider both sensor location and time scale of LDE when calculating local gait stability in PwMS.