UC Berkeley

Refractive errors (e.g. nearsightedness or farsightedness) are the product of a mismatch between the axial length of the eye and its optical power, creating blurred vision. Uncorrected refractive errors are the second leading cause of world-wide blindness. One refractive error currently holding tremendous scientific interest is myopia (or near-sightedness), mostly due to its rising prevalence worldwide and associated ocular disease burden. That the increase in myopia prevalence has been rapid, occurring over a short period of time, suggests environmental influences in addition to genetic influences on eye growth. In this dissertation, the evidence for influences of genetic and environmental factors related to myopia development are presented as well as a discussion of the possible role of nutritional and body-metric factors through an analysis of NHANES data. Key environmental factors that have implicated in myopia development and/or progression relate to near work and outdoor activity, however traditional studies investigating these factors rely on subjective questionnaires. Possibly related to this limitation is the fact that no strong risk factors for myopia development have been described to date. The dissertation research presented here is novel in that it utilized objective technologies, including wearable technologies, to investigate the relationship between the dynamics of habitual indoor and outdoor behaviors, including the lighting characteristics experienced, to myopia presence and severity in young adult university students in both an academic and non-academic period.