Statistical Learning as a Novel Intervention for Cortical Blindness

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.

Study Overview

• Status: Enrolling by invitation
• Conditions: Stroke, Ischemic; Stroke Hemorrhagic; Hemianopia, Homonymous; Visual Field Defect, Peripheral; Hemianopsia; Quadrantanopia; Occipital Lobe Infarct; Vision Loss Partial
• Intervention / Treatment: Device: Vision Training and Learning Task

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • New York
    • Rochester, New York, United States, 14642
      • University of Rochester Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Cortically Blind participants

Inclusion criteria:

• 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

Exclusion criteria:

• 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

Inclusion criteria:

• Between 21 and 75 years of age
• No history of neurological disorder.
• Competent and responsible, as determined by the screening interview

Exclusion criteria:

• Any damage to the visual system
• Those who are suffering from an active disease process involving their nervous system.
• Presence of cognitive or seizure disorders
• Best corrected visual acuity worse than 20/40 in either eye
• Presence of visual field loss from ocular disease or disorder

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Visual Training in Cortically Blind cohort	Device: Vision Training and Learning Task; 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.
Experimental: Visual Training in Control cohort	Device: Vision Training and Learning Task; 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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
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

Collaborators and Investigators

• Sponsor: University of Rochester

Study record dates

Study Major Dates

• Study Start (Actual): November 6, 2024
• Primary Completion (Estimated): October 1, 2027
• Study Completion (Estimated): October 1, 2027

Study Registration Dates

• First Submitted: August 27, 2024
• First Submitted That Met QC Criteria: August 27, 2024
• First Posted (Actual): August 29, 2024

Study Record Updates

• Last Update Posted (Actual): January 30, 2026
• Last Update Submitted That Met QC Criteria: January 28, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: vision recovery; occipital stroke; vision loss after stroke; vision restoration; partial vision loss
• Additional Relevant MeSH Terms: Neurologic Manifestations; Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Eye Diseases; Vision Disorders; Sensation Disorders; Blindness; Stroke; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Ischemic Stroke; Hemorrhagic Stroke; Hemianopsia
• Other Study ID Numbers: STUDY00009495

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No