Three months of home-based adaptive grating-detection training improved visual acuity, grating acuity, motion contrast sensitivity, and quality of life in patients with diabetic retinopathy without changing OCTA parameters, indicating significant residual visual plasticity and supporting VPL as a potential treatment for DR.
Key Findings
Results
Home-based visual perceptual learning improved best-corrected visual acuity in DR patients relative to controls.
BCVA in the VPL group improved from 0.36 to 0.26 logMAR (P = 0.003).
A significant group × time interaction was found for BCVA (F1, 26 = 10.872, P = 0.003, ηp² = 0.295).
Thirty-six DR patients were randomized 1:1; 28 completed the study (VPL n = 12; control n = 16) after eight were excluded for poor adherence or incomplete follow-up.
The VPL group trained for 3 months at home with grating detection at individual cutoff spatial frequencies.
Results
VPL improved grating acuity substantially, and this was the largest group × time effect among the outcomes.
GA in the VPL group improved from 12.42 to 17.47 cycles per degree (2.96 dB).
Group × time interaction for GA: F1, 26 = 63.595, P < 0.001, ηp² = 0.710.
Results
Contrast sensitivity to first-order motion stimuli (1stM) increased after training on a static contrast detection task, suggesting transfer to motion perception.
1stM increased from 64.26 to 83.42 (2.27 dB) in the VPL group.
Group × time interaction for 1stM: F1, 26 = 32.663, P < 0.001, ηp² = 0.557.
The authors suggest contrast detection training may extend to motion perception tasks.
Results
Vision-related quality of life improved after VPL and the improvement correlated with the gain in grating acuity.
LVQOL score increased by 4.33 points (P < 0.001).
LVQOL change correlated with ΔGA (r = 0.671, P = 0.017).
Results
OCTA parameters remained stable in both groups, so functional improvements were not accompanied by measurable changes in retinal microvasculature.
OCTA was assessed at baseline, 1 month, and 3 months in the VPL group and at baseline and 3 months in controls.
Stable OCTA indicates the visual gains are unlikely to reflect retinal vascular changes, consistent with a neural plasticity mechanism.
Conclusions
The results indicate significant residual visual system plasticity in diabetic retinopathy and support VPL as a potential treatment.
Patients were receiving routine DR therapies during the study.
Improvements were found across acuity, contrast sensitivity, and quality-of-life measures.
The sample was small, with 8 of 36 randomized participants excluded for poor adherence or incomplete follow-up.
What This Means
This study tested whether a home-based visual training program could improve vision in people with diabetic retinopathy, a diabetes-related eye disease that damages the retina. Thirty-six patients already receiving routine care were randomly assigned to either do three months of at-home training or to serve as controls. The training involved detecting faint striped patterns (gratings) set at each person's own limit of detail. Twenty-eight people completed the study.
People who did the training showed improvements in standard letter-chart vision, in the ability to see fine striped patterns, and in sensitivity to contrast in moving patterns, compared with the control group. They also reported better vision-related quality of life, and those who gained more in fine-detail vision tended to report larger quality-of-life gains. Imaging of the retina's blood vessels did not change in either group, suggesting the benefits probably came from the brain adapting to make better use of the visual signals, rather than from healing of the retina.
This research suggests that the visual system in people with diabetic retinopathy can still adapt and improve with training, and that training on one kind of task may help with others, such as motion perception. However, the study was small, and some participants dropped out or did not follow the program, so larger studies are needed to confirm the results and to determine how long the benefits last.
Cao K, Luo S, Xiang X, Zhao Q, Ma W, Feng L. (2026). Visual Perceptual Learning Based on Adaptive Contrast Detection Training Enhances Vision and Contrast Sensitivity in Diabetic Retinopathy.. Investigative ophthalmology & visual science. https://doi.org/10.1167/iovs.67.13.9