Abstract
The foveated architecture of the human retina and the eye’s mobility enable prime spatial vision, yet the interplay between photoreceptor cell topography and the constant motion of the eye during fixation remains unexplored. With in vivo foveal cone-resolved imaging and simultaneous microscopic photo stimulation, we examined visual acuity in both eyes of 16 participants while precisely recording the stimulus path on the retina. We find that resolution thresholds were correlated with the individual retina’s sampling capacity, and exceeded what static sampling limits would predict by 18 %, on average. The length and direction of fixational drift motion, previously thought to be primarily random, played a key role in achieving this sub-cone diameter resolution. The oculomotor system finely adjusts drift behavior towards retinal areas with higher cone densities within only a few hundred milliseconds to enhance retinal sampling.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
As part of the revision process at eLife, we have added some analyses and figures to the manuscript that we felt would add to but not overload the paper. Other more nuanced analyses requested are shown in the response to the peer review only (Figures R1-R3). They will be however available to all readers in the eLife online format.
