Sensory Substitution and Brain Plasticity Following Vision Loss

NCT07450677 | Not Yet Recruiting FDA Device

• 2 other identifiers: 80671R01EY034897
• Study Type: interventional
• Target: 200
• Locations: 1 country
• Sites: 2

Brief Summary

The goal of this clinical investigation is to learn how the brain responds when visual information is converted into patterns of sound or touch in blind and sighted participants. The main questions it aims to answer are:

• Does converting visual information into sound or touch patterns change visual performance in the blind or blindfolded?
• How does the brain adapt to different kinds of sensory information? Researchers will use brain imaging and simple performance tasks to see how people process and learn from this type of converted sensory input. The investigators will compare how individuals with and without long-term vision loss respond to these signals. Participants will:
• Learn to use technologies to assist in visual information conversion into sound or touch patterns every day for 5 weeks;
• Visit the brain imaging center 3 times for brain scans and behavioral tests.

Conditions

Blindness

Keywords

Blindness; Visual cortex; Sensory substitution; Assistive technology; Magnetic resonance imaging; Brain; Sound; Touch

Outcome Measures

Primary Outcomes (4)

• Number of correct responses to visual performance tasks

  Measuring the change in the number of correct responses to visual performance tasks from baseline to week 5.

  5 weeks

• Reaction time to visual performance tasks

  Measuring the change in reaction time to visual performance tasks from baseline to week 5.

  5 weeks

• Metabolic brain profile

  Measuring the change in neurometabolic markers by magnetic resonance spectroscopy from baseline to week 5.

  5 weeks

• Blood-oxygenation-level-dependent functional brain activity level

  Measuring the change in blood-oxygenation-level-dependent brain activity level by T2\*-weighted functional magnetic resonance imaging from baseline to week 5.

  5 weeks

Secondary Outcomes (2)

• Gray matter density

  5 weeks

• White matter directional diffusivity

  5 weeks

Study Arms (3)

Vision-to-sound sensory substitution training

EXPERIMENTAL

Participants will learn to interpret the sound patterns that are converted from visual information while using the assistive technology.

Device: Vision-to-sound converter (AI Sight)

Vision-to-touch sensory substitution training

EXPERIMENTAL

Participants will learn to interpret the touch patterns that are converted from visual information while using the assistive technology.

Device: Electrotactile display (BrainPort)

Sham training

SHAM COMPARATOR

Participants will learn to interpret the sound/touch patterns verbally without presenting the sensory signals from the assistive technologies.

Device: Sham

Interventions

Electrotactile display (BrainPort) DEVICE

The BrainPort is a non-surgical assistive device that translates digital information from a video camera to gentle electrotactile stimulation patterns on the surface of the tongue.

Vision-to-touch sensory substitution training

Vision-to-sound converter (AI Sight) DEVICE

The AI Sight is an auditory technology software that can convert visual information into sound patterns, which can be delivered through regular headphones.

Vision-to-sound sensory substitution training

Sham DEVICE

Participants will wear the assistive technology system, but there will be no active sensory signals applied.

Sham training

Eligibility Criteria

• Age: 8 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• years old for blind individuals; or 18-85 years old for sighted controls.
• (a) Blind due to ocular impairment (documented visual acuity of light perception or worse) in both eyes, or (b) sighted healthy adult controls with corrected visual acuity of 20/40 or better and with no known vision disorders.
• Able to hear the Informed Consent Form being read out to him or her, to understand it, and sign the Informed Consent Form.
• Able to undergo functional neuroimaging tests.
• Able to walk and stand independently.
• Able to understand and remember the training protocols involved in the research study.
• Willing and able to use the provided sensory substitution system to solve simple visual tasks.
• Willing and able to complete simple tactile or auditory tasks.
• Able to communicate by telephone and/or computer with research staff.

You may not qualify if:

• Prior use with the sensory substitution device under investigation. This applies to both the auditory and tactile stimulators.
• Presence of any foreign metal in the body, except for dental fillings (will need to be pre-screened by a radiologist prior to signing the informed consent and enrollment).
• Pregnant or breastfeeding by self-report or urine test.
• Is a prisoner or has any required movements legally restricted.
• Unwilling or unable to adhere to all study requirements, including completion of the training period and any evaluation tests.
• Implanted electrical medical devices such as pacemakers.
• Claustrophobia that would prevent functional neuroimaging.
• Obesity preventing placement in the MRI scanner.
• No known neurological disorders or any medical condition that can possibly lead to emergency medical care (e.g., history of seizures, family history of epilepsy, stroke, severe headaches, use of medication for neurological or psychiatric conditions).
• Documented or suspected brain damage resulting in significant cognitive or sensory impairment (e.g., traumatic brain injury).

Sponsors & Collaborators

• Stanford University: lead
• National Eye Institute (NEI): collaborator

Study Sites (2)

Byers Eye Institute at Stanford University

Palo Alto, California, 94303, United States

Location

LUCAS Center for Imaging

Stanford, California, 94305, United States

Location

MeSH Terms

Conditions

Blindness

Condition Hierarchy (Ancestors)

Vision Disorders; Sensation Disorders; Neurologic Manifestations; Nervous System Diseases; Eye Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Kevin C. Chan, PhD

  Stanford University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Study Team

CONTACT

650-497-0625; kevinchan@stanford.edu

Mariana Nunez, CCRP

CONTACT

650-497-7846; mnunez1@stanford.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor of Ophthalmology

Model Details: A parallel model will be used, in which participants are assigned to one of the two sensory substitution devices for the duration of the study.

Study Record Dates

• First Submitted: February 24, 2026
• First Posted: March 5, 2026
• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): August 31, 2030
• Study Completion (Estimated): August 31, 2030
• Last Updated: March 5, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (2)