Characterization of Multiple Factors in Training and Plasticity in Central Vision Loss: Macular Degeneration
University of Alabama at Birmingham
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.
Description
Research on perceptual learning (PL) has been dominated by studies that seek to isolate and improve individual visual processes. However, an important translational outcome of PL research is to address the needs of patients with vision loss, who seek to improve performance on daily tasks such as reading, navigation, and face recognition. These more ecological cases of behavioral change and cortical plasticity, which are inherently complex and integrative, have revealed significant gaps in a more holistic understanding of how multiple visual processes and their associated brain systems jointly…
Eligibility
- Age range
- 18–89 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * 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 Exclusion Criteria: * Pacemaker or any ferromagnetic metal implanted in their body * Metal of any type implanted in their head (limited dental…
Interventions
- BehavioralTraining 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.
- BehavioralCombination 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, this condition combines elements of training visual sensitivity, spatial integration, and spatial attention.
Location
- UABBirmingham, Alabama