Optometrists have several methods for treating patients with amblyopia, but the relationship between eye dominance and acuity is not fully understood. Currently, most researchers believe discordant vision in amblyopia “exaggerates eye dominance and thereby limits processing of visual information from the affected eye and lowers visual performance.”1 However, new research out of the University of Louisville offers a surprising conclusion that may turn the treatment protocol for amblyopia on its head. The researchers suggest that the neural circuit mechanisms underlying recovery of eye dominance and acuity operate independently.1
“Degrading vision by one eye during a developmental critical period yields enduring deficits in both eye dominance and visual acuity,” according to the animal-model study. “Here, we demonstrate that plasticity of eye dominance and acuity are independent and restricted by the nogo-66 receptor (ngr1) in distinct neuronal populations.”
The testing evaluated the visual acuity of mice for whom the ngr1 gene had been removed; the results demonstrate that, even for mice whose eye dominance remained impaired, visual acuity could still improve.
1. Stephany C, Ma X, Dorton H, et al. Distinct circuits for recovery of eye dominance and acuity in murine amblyopia. Current Biology. June 7, 2018. www.cell.com/current-biology/fulltext/S0960-9822(18)30527-X. Accessed June 11, 2018. |