Debora Nickla, PhD, Professor of Biology at New England College of Optometry, was recently awarded a $1.4 million grant by the National Eye Institute of the National Institutes of Health (NIH) to support her research entitled, “Vision, eye growth rhythms, and retinal signals in refractive development.” Awarded for a period of three years, the grant project will focus on circadian rhythms and how they influence eye growth.
The reasons behind the development of myopia and its increasing incidence, particularly among educated people, remain obscure. Dr. Nickla notes, “because the eye can modulate its growth even if the optic nerve is severed, and because retinal defocus that is restricted to one area only affects the eye growth underlying that restricted area, it follows that the retina is able to detect the sign of the defocus and control the eye’s growth. However, despite two centuries of study, prophylactic treatments against childhood myopia are limited to atropine drops, contact lenses that reshape the cornea, or stabilizing treatments for the sclera, all of which have potential side effects and limited efficacy.” The study will investigate how time of day of visual stimulation might have differential effects on eye growth. It will also explore how these effects may be linked to preventing myopia in children, for instance by exposure to sunlight at certain times. Dr. Nickla explains, “Understanding how attributes of the visual environment influence the signal cascade between retina and sclera to produce myopia is crucial to developing therapies that will ameliorate it.”
Dr. Nickla’s research has focused on myopia and circadian rhythms for over twenty years. Work in her lab, along with those of Dr. Richard Stone at the University of Pennsylvania and Dr. Michael Iuvone at Emory University, has linked the development of ametropias to alterations in ocular circadian rhythms. This work has revealed that eyes show shifts in phase and changes in amplitude of the rhythms in eye growth (axial length) and choroidal thickness that depend on the visual stimulus and are linked to changes in ocular growth. Together with Drs. Stone and Iuvone, Dr. Nickla will take an interdisciplinary approach to her new research in order to examine how circadian rhythms influence eye growth by applying molecular biology to the mechanisms underlying refractive development.
Dr. Nickla explains, “Understanding the molecular basis of the alterations of ocular circadian rhythms driven by the retinal clock will stimulate the identification of much-needed, effective approaches to normalize refractive development in children.”