Factors in Learning And Plasticity: Macular Degeneration

NCT05454124 | Recruiting

• 1 other identifier: 300006197 (Study 2)
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

A greater understanding of plasticity after central vision loss can inform new therapies for treating low vision and has the potential to benefit millions of individuals suffering from low vision. The treatment of low vision is particularly relevant to the mission of the NEI to support research on visual disorders, mechanisms of visual function, and preservation of sight. The comparison of different training and outcome factors is in line with the NIMH RDOC framework and studies in an aging population are consistent with the mission of the NIA.

Conditions

Central Visual Impairment; Macular Degeneration

Keywords

plasticity; central vision loss; perceptual learning

Outcome Measures

Primary Outcomes (3)

• Change from Baseline Radial Bias from the Crowding Task after completion of Training at approximately 7 weeks

  The ratio of the crowding threshold along the axis connected to the fovea vs. along the orthogonal axis.

  Baseline and Within 3 weeks of training completion, training is complete 7 weeks from baseline on average

• Change from Baseline Saccadic Precision after Completion of Training at approximately 7 weeks

  Consistency across trials in placement of the first saccade calculated by the distribution across trials (bivariate contour ellipse area) of the landing point of the first fixation of each trial.

  Baseline and Within 3 weeks of training completion, training is complete 7 weeks from baseline on average

• Change from Baseline Fixation Stability after Completion of Training at approximately 7 weeks

  Normalizing fixations in the PRL to the first fixation to that region and calculating the distribution of all fixation locations in this normalized space (measured as a bivariate contour ellipse area).

  Baseline and Within 3 weeks of training completion, training is complete 7 weeks from baseline on average

Other Outcomes (18)

• Change from Baseline Acuity after Completion of Training at approximately 7 weeks

  Baseline and Within 3 weeks of training completion, training is complete 7 weeks from baseline on average

• Change from Baseline Contrast Sensitivity after Completion of Training at approximately 7 weeks

  Baseline and Within 3 weeks of training completion, training is complete 7 weeks from baseline on average

• Change from Baseline Minimal print size from the MNREAD task after Completion of Training at approximately 7 weeks

  Baseline and Within 3 weeks of training completion, training is complete 7 weeks from baseline on average

Study Arms (2)

Training visual sensitivity

EXPERIMENTAL

A standard Perceptual Learning approach to train early visual processes of discriminating the orientation of Gabor patches presented at threshold- level contrast. Preliminary data, using this method, in normally seeing and MD participants show both feasibility and preliminary evidence that this training gives rise to improvements in acuity.

Behavioral: Training visual sensitivity

Combination training

EXPERIMENTAL

In combination training, investigators test the extent to which a combined training gives rise to the joint benefits of each training individually, or integrative benefits potentially surpassing benefits of the individual training alone. The visual sensitivity task will alternate across blocks with the spatial integration task, using the timing of targets and location switches from spatial attention training.

Behavioral: Combination training

Interventions

Training visual sensitivity BEHAVIORAL

Investigators adopt a standard PL approach to train early visual processes of discriminating the orientation of Gabor patches presented at threshold contrast. Across training blocks, Gabors will range in spatial frequency, where contrast is adapted with a 3/1 staircase. Whenever a specific contrast threshold is reached, spatial frequency will increase by 2 cycles per degree and contrast will be reset. Preliminary data from this method in normally seeing and MD participants show both feasibility and tentative evidence that this training gives rise to improvements in acuity.

Training visual sensitivity

Combination training BEHAVIORAL

Daily tasks involve a combination of being sensitive to basic visual features, being able to integrate these features, and directing attention and eye movements to better evaluate the information of potential interest. To address this integrative nature of real-world vision, this condition combines elements of training visual sensitivity, spatial integration, and spatial attention.

Combination training

Eligibility Criteria

• Age: 18 Years - 89 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Aged 18-89
• Severely impaired vision in both eyes (20/100 or worse)
• diagnosis of Macular Degeneration by an Ophthalmologist
• Light sensitivity in the macular retina that is at least 10 dB units worse than in peripheral regions, as demonstrated by a scanning laser ophthalmoscope (MAIA)
• Medical record review indicating this level of disease severity has been present for at least 2 years
• Reside within 50 miles of study site

You may not qualify if:

• Pacemaker or any ferromagnetic metal implanted in their body
• Metal of any type implanted in their head (limited dental work is acceptable)
• Claustrophobia
• Being hearing-impaired
• Weight over 300 pounds
• Maximum body girth over 60 inches
• Previous serious head injury
• Presence of hallucinations or delusions
• Excessive old, or colorful tattoos, especially near the head
• Pregnancy
• Braces/permanent retainer

Sponsors & Collaborators

• University of Alabama at Birmingham: lead
• University of California, Riverside: collaborator

Study Sites (1)

UAB

Birmingham, Alabama, 35294, United States

RECRUITING

MeSH Terms

Conditions

Blindness, Cortical; Macular Degeneration; Scotoma

Condition Hierarchy (Ancestors)

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

Central Study Contacts

Rachel A Chua, MS

CONTACT

205-410-4041; r2chel@uab.edu

Kristina M Visscher, PhD

CONTACT

205-934-0497; kmv@uab.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: July 5, 2022
• First Posted: July 12, 2022
• Study Start: November 1, 2022
• Primary Completion (Estimated): November 1, 2026
• Study Completion (Estimated): November 1, 2026
• Last Updated: February 9, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, ICF, ANALYTIC CODE
• Time Frame: Within one year of the final participant completing data collection.

Locations

US (1)