Comparative age-related decline in accommodative amplitude in the rhesus monkey (centrally stimulated, objectively measured) and human (voluntary; subjectively measured) accommodation based on a lifespan of 35 and 75 years, respectively.
Solid circles: maximum centrally stimulated accommodation versus age in 22 rhesus monkeys (age range, 5.7–24 years) 2 weeks after midbrain electrode implantation for the present study.
Solid line: least-squares regression of centrally stimulated accommodation on age (
solid circles). Centrally stimulated maximum accommodative amplitude declined with age by −0.76 ± 0.07 D/y (
P = 0.001). Rhesus monkey data (
open circles) represent maximum accommodation induced by central stimulation in data collected by Neider et al.
7 (adapted, with permission, from Neider et al.
In vivo videography of the rhesus monkey accommodative apparatus: age-related loss of ciliary muscle response to central stimulation.
Arch Ophthalmol. 1990;108:69–74. ©
American Medical Association). Human data (
shaded area) represent the range of maximum voluntary accommodation (adapted, with permission, from Duane. Studies in monocular and binocular accommodation with their clinical applications.
Am J Ophthalmol. 1922;5:867–877, © Elsevier).
Dashed line: least-squares regression of all monkey data (Neider et al.
7 and current data).