Statistical Learning as a Novel Intervention for Cortical Blindness

NCT06578117 | Enrolling By Invitation

• 1 other identifier: STUDY00009495
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

This project aims to develop a novel visual training paradigm for use in visually-intact participants and those sufferings from stroke-induced visual impairments. Our task design is built upon theories of statistical learning to reduce the overall training burden while still producing profound improvements to visual abilities. Efficacy will be first established in visually-intact controls before testing in stroke survivors to assess the feasibility of this form of learning in the damaged visual system.

Conditions

Stroke, Ischemic; Hemianopia, Homonymous; Hemianopsia; Occipital Lobe Infarct; Visual Field Defect, Peripheral; Vision Loss Partial; Quadrantanopia; Stroke Hemorrhagic

Keywords

occipital stroke; vision loss after stroke; vision recovery; vision restoration; partial vision loss

Outcome Measures

Primary Outcomes (2)

• Explicit Learning - Response Time

  Reaction time (ms) when performing motion discriminations for the final stimulus of a statistically-linked triplet will be compared against reaction times for stimuli with identical motion directions, presented with alternative placement within a triplet. Comparisons will be made only for correct responses in the final 20% of overall testing session trials.

  Baseline

• Implicit Learning - Triplet Familiarity

  Participant familiarity with statistically-linked triplets of motion will be assessed via a two-interval, forced-choice task. Familiarity will be measured as a percentage of comparisons in which the more prevalent triplet is selected as more familiar. Familiarity of high-probability, low-probability, and null-probability triplets will be compared following training.

  Baseline

Study Arms (2)

Visual Training in Cortically Blind cohort

EXPERIMENTAL

Device: Vision Training and Learning Task

Visual Training in Control cohort

EXPERIMENTAL

Device: Vision Training and Learning Task

Interventions

Vision Training and Learning Task DEVICE

Participants will be seated at a computer, and will be shown a random-noise visual stimulus drifting in one of eight directions. Participants will be instructed to indicate the direction of motion they perceive using a Sony Access Controller or a computer keyboard. Sound cues during stimulus presentation will also be used to ensure participants are aware of stimulus onset during the training task. After several repetitions of this visual training, a second set of visual cues will be presented to evaluate participant's learning of the program. Responses will be provided in the same manner by input from the controller or the keyboard.

Visual Training in Control cohort; Visual Training in Cortically Blind cohort

Eligibility Criteria

• Age: 21 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Between 21 and 75 years of age
• Residents of the United States or Canada
• Have successfully completed previous enrollment in Dr. Huxlin study (IRB #5966 or #75)
• Exhibit unilateral stroke or stroke-like damage to primary visual cortex or its immediate afferent white matter sustained within the specified age range of 21 - 75 years (verified by MRI and/or CT scans)
• Reliable visual field defects in both eyes (homonymous defects) as measured by Humphrey visual fields. This deficit must be large enough to enclose a 5-deg diameter visual stimulus.
• Able to fixate on visual targets reliably for 1000ms within 1-deg of visual angle.
• Willing, able, and competent to provide their own informed consent
• Normal cognitive abilities and be able to understand written and oral instructions in English

You may not qualify if:

• Past or present ocular disease interfering with visual acuity
• Best corrected visual acuity (BCVA) worse than 20/40 in either eye
• Sustained documented or suspected damage to the dorsal Lateral Geniculate Nucleus
• Presence of diffuse whole brain degenerative processes
• History of traumatic brain injury
• Any other brain damage deemed by study staff to potentially interfere with training ability or outcome measures
• Documented history of drug/alcohol abuse
• Currently taking neuroactive medications which would impact training, as determined by PI
• Cognitive or seizure disorders
• One-sided attentional neglect
• Those who lack the competence or are otherwise unable to perform the visual training exercises as directed.
• Control participants
• Between 21 and 75 years of age
• No history of neurological disorder.
• Competent and responsible, as determined by the screening interview

Sponsors & Collaborators

• University of Rochester: lead

Study Sites (1)

University of Rochester Medical Center

Rochester, New York, 14642, United States

Location

MeSH Terms

Conditions

Ischemic Stroke; Hemianopsia; Hemorrhagic Stroke

Condition Hierarchy (Ancestors)

Stroke; Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Vision Disorders; Sensation Disorders; Neurologic Manifestations; Blindness; Eye Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

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: Research Assistant Professor

Study Record Dates

• First Submitted: August 27, 2024
• First Posted: August 29, 2024
• Study Start: November 6, 2024
• Primary Completion (Estimated): October 1, 2027
• Study Completion (Estimated): October 1, 2027
• Last Updated: January 30, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)