Awesome, thanks. My searches must have missed these, as I was focusing on UV radiation rather than outdoor activity. It looks like there's still a ways to go to understanding the causes of myopia.
Significant changes in optical axial length occurred in human subjects after 60 minutes of monocular defocus. The bidirectional optical axial length changes observed in response to defocus implied the human visual system is capable of detecting the presence and sign of defocus and altering optical axial length to move the retina toward the image plane.
Training of the accommodative system in these progressing myopes resulted in improved dynamics in both laboratory and clinical measures. This is consistent with earlier reports in the literature of improvement in symptomatic myopic subjects.
