title: Edinger--Westphal stimulated accommodative dynamics in anesthetized, middle-aged rhesus monkeys.
abstract: The relationships between peak velocity and amplitude of Edinger-Westphal (EW) stimulated accommodation and disaccommodation were investigated in anesthetized, middle-aged rhesus monkeys. Accommodative responses were recorded at 30Hz with infrared photorefraction. Peak velocity of accommodation and disaccommodation increased linearly with stimulus amplitude. Peak velocities of accommodation continued to increase with stimulus amplitudes greater than required to produce the maximum response. The peak velocity of disaccommodation did not further increase with supramaximal stimulus amplitudes beyond that achieved with maximal stimulus amplitudes. Although maximum accommodative response amplitude is reduced in older rhesus monkeys, within the methodological constraints of this study, older monkeys appear to achieve accommodative and disaccommodative peak velocities similar to adolescent monkeys for the same response amplitudes.
authors.affiliation: College of Optometry, University of Houston, 4901 Calhoun Road, Houston, TX 77204-2020, USA.
authors.forename: Martin
authors.initials: M
authors.lastname: Baumeister
authors.forename: Mark
authors.initials: M
authors.lastname: Wendt
authors.forename: Adrian
authors.initials: A
authors.lastname: Glasser
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology*; D000375:Aging / Q000502:physiology*; D000768:Anesthesia, General; D000818:Animals; D002217:Carbachol; D004558:Electric Stimulation / Q000379:methods; D007908:Lens, Crystalline / Q000502:physiology; D008253:Macaca mulatta; D008916:Miotics; D012029:Refraction, Ocular / Q000502:physiology
chemical_list: D008916:Miotics; D002217:Carbachol