Neural contrast sensitivity is not affected by myopic blur.

The prevalence of myopia is increasing worldwide, accompanied by an increase of potentially under-corrected myopes. Because neural pathways are prone to adaptation in relation to the sensory input, we wondered to what extent neural contrast sensitivity (NCS) is altered in the presence of image blur arising from under-correction. No significant differences in NCS were observed between the three groups but were significantly equivalent between emmetropes, well-corrected, and under-corrected myopes (all p < 0.001). Across all healthy participants, NCS variability increased with increasing spatial frequency which could not be explained by variations in foveolar cone density. For an albinism patient, a large difference between the cut-off frequency and central cone density derived Nyquist sampling limit was observed. In conclusion, NCS is unaffected by myopia and remains stable for under-correction of up to 1.5 D. Furthermore, NCS testing can relate visual deficits to an underlying neurological disorder.