Cerebral Visual Impairment, Oddball Design, Passive Visual Stimulation, Perceptual Learning, Visual Rehabilitation
Conditions
Keywords
visual rehabilitation, visual stimulation, perceptual learning
Brief summary
Restorative visual rehabilitation is frequently used to enhance the visual development and function of children with low vision. An important strategy within this field is visual stimulation, which is particularly used for infants and toddlers with low vision, as well as for children who have both developmental disabilities and low vision.This study has two primary objectives.The first objective is to examine the effect of using intensive, specific, and flickering black-and-white checkerboard patterns to enhance visual function in children with mild to moderate low vision. The second objective is to develop a visual stimulation program tailored for children with severe or profound multiple disabilities and visual impairments, and to evaluate its effectiveness. For both objectives, the visual stimulation intervention will be provided through either in-person or remote delivery
Detailed description
Investigators will recruit 200 children with various types and severities of visual disorders. Additionally, investigators will collect eye movement assessment data using an eye-tracking system from 30 typically developing infants under two years old to validate the oculomotor assessment newly designed for this study. For this component, the reliability of our oculomotor assessment will be validated through test-retest reliability in both typically developing children and children with multiple disabilities and visual impairments who are enrolled in visual rehabilitation. The intervention programs include two types: 1. One program provides extensive passive visual stimulation, incorporating attentional modulation during the process to facilitate training. Passive visual stimulation is delivered continuously using appropriate visual materials tailored to the participants' visual abilities, such as illuminated toys or high-contrast patterns. These stimuli are positioned around infants or children, or repeatedly presented by caregivers. This approach allows young children or those with lower cognitive abilities and visual impairments to receive visual stimulation even without active participation. Through this passive intervention model, visual function can be improved.The intervention may be delivered either in person at the study site or remotely through a tele-rehabilitation platform, following the same study procedures and stimulation protocols. Although this model is flexible and suitable for infants or children with low compliance, it poses challenges in quantifying the amount of visual training provided. This limitation affects the ability to verify the efficacy of interventions in clinical trials. This version incorporates technical terms and ensures clarity for academic or clinical documentation, while emphasizing the model's flexibility and its limitations. 2. Another program provide checkerboard pattern, a fundamental visual element processed by the early vision system, is used widely in vision science research, visual function assessment, and training. This program incorporates perceptual learning theories that emphasize attentional modulation and the oddball design concept. Salient oddball patterns appear randomly within the ongoing checkerboard reversal stimuli. Participants are required to press a special button when these patterns appear, with engaging auditory feedback provided to reinforce correct responses. This design aims to sustain the visual attention of visually impaired infants and children on the checkerboard reversal patterns for longer durations. Neurologically, the program strengthens top-down modulation mechanisms in the brain through random salient stimuli, enhancing bottom-up processing of early visual information. Researchers adjusted square sizes through trial-and-error and clinical experience, often enlarging the squares to engage the children effectively. However, this strategy may not fully accommodate children with low vision combined with developmental disabilities. Behavioral observations suggest that integrating sVEP to identify occipital response thresholds and utilizing eye-tracking systems could refine square size adjustments and improve intervention strategies and outcome evaluations. Additionally, this program may not be suitable for children with severe or profound low vision. The need for quick physical or verbal responses to transient oddball stimuli and the requirement to recognize checkerboard patterns demand a certain level of visual acuity and sustained attention. These factors pose challenges for children with severe multiple disabilities (MDVI), who often require longer response times, have shorter attention spans, and struggle with repetitive tasks. Despite these challenges, MDVI children exhibit visual plasticity, making visual stimulation interventions valuable. Developing alternative visual stimulation programs tailored to the needs of children with severe or profound MDVI is essential for maximizing their potential benefits.
Interventions
BEHAVIORALrestorative visual rehabitation
black-and-white checkerboard patterns, visual stimulation program, restorative visual rehabitation
Sponsors
National Taiwan University Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
1 Months to 18 Years
Healthy volunteers
No
Inclusion criteria
Passive visual stimulation group Inclusion Criteria: 1. Children aged less than or equal to 18 years old. 2. The causes of visual disorder in children are unlimited. 3. The acuity of the children's better eye was ≤ 0.2. 4. Children with multiple disabilities and visual disorders typically exhibit developmental levels ranging from moderate to severe or below. 5. The parents of these children exhibit a positive attitude and are willing to cooperate with visual learning programs. 6. Infants under 1 year old with low vision without other developmental issues , under or equal to moderate developmental issues.
Exclusion criteria
1. Significant refractive errors that affect acuity but are unable to cooperate with wearing corrective glasses in two training sessions. 2. Requires patching for monocular vision rehabilitation but is unable to cooperate with patching in two training sessions. 3. The individual is unable to adapt to the training environment and cooperate with visual learning in two sessions due to unstable emotions or difficulty adapting to the environment. Perceptual learning group Inclusion Criteria (1)Children aged less than or equal to 12 years old. (2)No restrictions on the causes of visual impairment in children. (3)The acuity of the children's better eye was ≤ 0.5 (4)If children have additional developmental issues, their disability severity should primarily be mild or moderate. (5)The primary caregiver demonstrates a positive attitude and is willing to cooperate with the visual training program. (6)The child is capable of completing calibration with an eye-tracking device.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Visual Function Battery for Children with Special Needs | From enrollment to one year after the end of treatment | Visual Function Battery for Children with Special Needs (VFB-CSN) is typically conducted by occupational therapists with experience in visual rehabilitation. It is a scale used to evaluate the visual function of children with special needs. It assesses eight aspects: visual reflection, eyeball asymmetry, visual acuity, contrast sensitivity, visual field, eye movements, color and shape perception, and visual attention. The scale includes 27 questions and combines standardized tests with functional assessment methods. The functional assessment method can be applied to cases that cannot cooperate with standardized tests. Children with varying degrees of visual impairment, ranging from light perception to identifiable visual targets, can be assessed using the VFB-CSN alone. The assessment scale has a maximum score of 60 and a minimum score of 0, with higher scores indicating better performance. |
| Functional Vision Questionnaire | From enrollment to one year after the end of treatment | This questionnaire is completed by the primary caregiver. It is designed for children with severe central nervous system disorders, such as children with cerebral palsy, to evaluate their visual performance under different brightness conditions and during daily activities. The scale consists of 28 questions, with a maximum score of 140 and a minimum score of 28. Higher scores indicate better performance. |
| Eye Movement Assessment Behavioral Scale for Children | From enrollment to one year after the end of treatment | The scoring is conducted by occupational therapists with experience in visual rehabilitation, based on their observation of the child's performance. This assessment employs an eye tracker and PowerPoint to create an eye movement assessment program before and after rehabilitation. It evaluates children's abilities in fixation, tracking, and saccadic movements in response to visual stimuli of varying sizes, contrasts, directions, speeds, and positions. The assessment scale has a maximum score of 64 and a minimum score of 8, with higher scores indicating better performance. |
| Near Detection Scale | From enrollment to one year after the end of treatment | Near Detection Scale (NDS) is performed by clinicians specializing in visual issues among children with special needs to quickly assess the detection acuity of children with severe and profound visual impairment. NDS is an 18-point scale, with 0 representing no light perception and 18 representing the ability to see 0.1 cm objects on a dark green background at a viewing distance of 30 cm. Higher scores indicate better visual acuity. |
| Visual Function Battery for Children with Special Needs-Revised (VFB-CSN-R) | At baseline (before the intervention) and immediately after completion of the intervention | The Visual Function Battery for Children with Special Needs-Revised (VFB-CSN-R) is conducted by occupational therapists experienced in pediatric visual rehabilitation. It is a revised clinical assessment developed from the original VFB-CSN to provide a more detailed evaluation of visual function in children with special needs. The battery evaluates eight domains: visual reflexes, ocular muscle balance, visual acuity, ocular motor function, visual field, contrast sensitivity, color and form vision, and visual attention. Compared with the original VFB-CSN, the VFB-CSN-R incorporates more detailed scoring criteria, particularly for ocular motor function, visual acuity, and contrast sensitivity. These revisions were intended to improve the instrument's ability to capture subtle differences and changes in visual function. Standardized assessments are performed whenever possible, whereas functional assessment methods are used for children who are unable to cooperate with conventional vision |
| Children's Functional Vision Questionnaire: Early Childhood Version (CFVQ-EC) | At baseline (before the intervention) and immediately after completion of the intervention | The Children's Functional Vision Questionnaire: Early Childhood Version (CFVQ-EC) is a questionnaire designed for completion by caregivers or professionals to evaluate functional vision in young children through observations of their daily visual behaviors. The questionnaire assesses visual performance across eight domains: visual acuity, visual field, contrast sensitivity, color vision, stereopsis, ocular motor function, visual perception, and visual attention. Age-specific items are arranged according to developmental milestones, enabling assessment from infancy through early childhood. Respondents answer "Yes" or "No" based on the child's typical performance in daily activities, play, learning, and social interactions. The questionnaire is designed as a screening tool to identify children who may have visual difficulties and require further ophthalmic or functional vision assessment. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Three-Day Daily of Children's Daily Visual Performance | From enrollment to one year after the end of treatment | This record is completed by the primary caregiver to document the child's visual behavior at home. The recording is conducted both before and after training to simultaneously capture the child's training activities and response status at home. |
Countries
Taiwan
Contacts
CONTACTLi-Ting Tsai, PhD
Outcome results
None listed