Biomechanical Considerations of Refreshable Braille and Tactile Graphics Toward Equitable Access: A Review

This review highlights the biomechanical foundations of braille and tactile graphic discrimination within the context of design innovations in information access for the blind and low-vision community. Braille discrimination is a complex and poorly understood process that necessitates the coordination of motor control, mechanotransduction, and cognitive-linguistic processing. Despite substantial technological advances and multiple design attempts over the last fifty years, a low-cost, high-fidelity refreshable braille and tactile graphics display has yet to be delivered. Consequently, the blind and low-vision communities are left with limited options for information access. This is amplified by the rapid adoption of graphical user interfaces for human-computer interaction, a move that the blind and low vision community were effectively excluded from. Text-to-speech screen readers lack the ability to convey the nuances necessary for science, technology, engineering, arts, and math education and offer limited privacy for the user. Printed braille and tactile graphics are effective modalities but are time and resource-intensive, difficult to access, and lack real-time rendering. Single- and multiline refreshable braille devices either lack functionality or are extremely cost-prohibitive. Early computational models of mechanotransduction through complex digital skin tissue and the kinematics of the braille reading finger are explored as insight into device design specifications. A use-centered, convergence approach for future designs is discussed in which the design space is defined by both the end-user requirements and the available technology.

Clinical Assessment of Visual Motion Perception in Children With Brain Damage: A Comparison With Base Rates and Control Sample

Aim: In this study, we examined (1) the presence of abnormally low scores (below 10^th percentile) in various visual motion perception aspects in children with brain damage, while controlling for their cognitive developmental delay; (2) whether the risk is increased in comparison with the observation and expectation in a healthy control group and healthy population. Methods: Performance levels of 46 children with indications of brain damage (M_age = 7y4m, SD = 2y4m) on three visual motion perception aspects (global motion, motion speed, motion-defined form) were evaluated. We used developmental age as entry of a preliminary reference table to classify the patient's performance levels. Then we compared the percentages of abnormally low scores with percentages expected in the healthy population using estimated base rates and the observed percentages in the control sample (n = 119). Results: When using developmental age as reference level, the percentage of low scores on at least one of the three tasks was significantly higher than expected in the healthy population [19/46, 41% (95%CI: 28-56%), p = 0.03]. In 15/19 (79% [95%CI: 61-97%] patients only one aspect of motion perception was affected. Four patients performed abnormally low on two out of three tasks, which is also higher than expected (4/46, 8.7%, 95%CI: 2.4-20.8% vs. 2.1%; z = 2.61, p < 0.01). The observed percentages in the patient group were also higher than found in the control group. Interpretation: There is some evidence that children with early brain damage have an increased risk of isolated and combined motion perception problems, independent of their performance IQ.

Emergent Literacy: A New Perspective

Emergent literacy, a process in which the child constructs concepts about the functions of symbols and print, is based on experiences and meaningful language facilitated by interactions with adults. This article presents a literature-based overview of emergent literacy and explores the fit between emergent literacy and the learning needs of children who are blind or visually impaired.

Behaviors of Preschoolers with Visual Impairments in Indoor Play Settings

This article reports on a study of the interaction, play, and other behaviors of 24 preschoolers with visual impairments and no other disabilities in the indoor play areas of two programs. The study found that the children interacted and played at lower levels than expected for 2–5 year olds and that their learning medium (visual or tactile) seemed to affect both the amount of interaction and the amount and type of play in which they engaged.

The Impact of Developmental Factors on Stereotypic Rocking of Children with Visual Impairments

Of 52 children who attended a sports camp for children with visual impairments, 15 demonstrated stereotypic rocking currently or in the past. Three factors were associated with rocking: etiology of visual impairment, visual status, and early medical history. Children who were the most likely to exhibit rocking were those with retinopathy of prematurity who underwent lengthy hospital stays and multiple surgeries early in their lives and who were totally blind from birth.

The Development of Rocking among Children who are Blind

This qualitative study of rocking in four children who are blind, aged 10–13, used in-depth interviews, observations, psychomotor assessments, and reviews of school and other records. The findings revealed similarities in the children's early medical histories, delays in motor development, constraints on vigorous movement, and limited peer relationships.

The Motor Development of Sighted Children and Children with Moderate Low Vision Aged 8–13

A study of the motor skills of 60 children aged 8–13—30 who were sighted and 30 who had moderate low vision—found that the children with low vision had poorer motor skills than did the children who were sighted. Furthermore, the children with low vision had weaker gross motor skills, especially balance, than fine motor skills. Implications for intervention are discussed.

Stereotyped Movements among Children who are Visually Impaired

Does the severity of visual impairment affect the prevalence and severity of stereotyped movements? In this study, children who were blind or had low vision, half of whom had intellectual disabilities, were assessed. The results revealed that blindness and global delays were associated with more sensory processing dysfunction and more stereotyped movements.

The relationship between stereotyped movements and self-injurious behavior in children with developmental or sensory disabilities

We assessed whether the stereotyped movements (SM) that are a defining characteristic of autism are discriminable from those observed in other disorders, and whether stereotyped self-injurious movements, which are excluded as exemplars of SM in DSM-IV, differ from other SM in severity or in kind. We used the Stereotyped and Self-Injurious Movement Interview to assess self-injurious and other SM in children with autism (n=56), intellectual disability (n=29), vision impairment (n=50), or hearing impairment (n=51) and in typical children (n=30). Cross-tabulation of scores indicated that self-injurious behavior is rarely performed in the absence of other SM. Reliability analyses indicated that patterns of covariation among SM items differ across groups so that different item sets are necessary to reliably measure SM in each group. Analyses of variance indicated the autism group exceeded one or more other groups in the frequency of 15 SM, the vision impaired group exceeded others on 5 SM, and the hearing impaired group exceeded others on 1 SM. Discriminant function analysis of SM items indicated that although only 66% of participants were accurately classified, it was rare for a child with a different disorder to be misclassified as having autism or visual impairment. We concluded that self-injurious behavior is a more severe form of SM, and there is a distinctive pattern of SM, including self-injurious behavior, that characterizes children with autism.

Exploration of surface-textures in congenitally blind infants

The haptic exploratory procedures that eight congenitally blind infants aged 8-24 months used to explore a gradient surface texture were investigated. Exploration of the gradient texture was examined over five sessions with 2 weeks between sessions, followed after 1 week by a sixth session, in which exploration of the gradient texture was compared to exploration of two other textures. Results showed that the infants have a wide range of exploratory strategies available and that the older infants can use these strategies in a specific manner. Results are discussed with reference to current ideas about the exploratory possibilities of congenitally blind infants. Use of texture in the stimulation of exploration of blind infants is discussed.