Factors in Learning And Plasticity: Healthy Vision

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 National Eye Institute (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 National Institute of Mental Health (NIMH) Research Domain Criteria (RDOC) framework and studies in an aging population are consistent with the mission of the National Institute on Aging (NIA).

Conditions

• Central Visual Impairment
• Macular Degeneration

Interventions

BEHAVIORAL

Condition 1: Training visual sensitivity

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.

BEHAVIORAL

Condition 2: Training spatial integration

Spatial integration involves what the investigators refer to as mid-level vision. Spatial integration is a concern in developing a PRL since an area of the visual periphery that is best suited to discriminate a simple visual feature may not be appropriate to integrate information across objects, such as in reading or recognizing facial identity or expression. The investigators address this issue with a targeted spatial integration training approach developed by MPI Seitz and based on contour integration tasks used in previous PL studies to train mid-level visual processes. Target stimuli consist of contours formed by spaced Gabors. The difficulty is manipulated by varying orientation jitter of Gabors. Several optotypes will be included to promote generalization, including shapes and facial expressions.

BEHAVIORAL

Condition 3: Training spatial attention

The investigators will implement a task structure that requires participants to alternate between holding and switching attention and making targeted eye movements. The basic task is to press a key whenever a red-circle appears in a series of other colored-circles, with a target presented every 2 to 4s. Participants must maintain vigilance for relatively long periods, detect objects in the near periphery, switch attention based upon exogenous and endogenous cues, and make eye- movements to move areas of spared vision to those locations. These are aspects of attention and eye movements not incorporated in Conditions 1 and 2.

BEHAVIORAL

Condition 4: Combination training

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,Condition 4 combines the elements of Conditions 1-3.

Sponsors & Collaborators

• University of California, Riverside

  collaborator OTHER

• University of Alabama at Birmingham

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

30 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2022-10-24

Primary Completion

2026-11-30

Completion

2026-11-30

Countries

• United States

Study Locations