Accommodation with and without short-wavelength-sensitive cones and chromatic aberration.
Accommodation was monitored while observers (23) viewed a square-wave grating (2.2 cycles/deg; 0.53 contrast) in a Badal optometer. The grating moved sinusoidally (0.2 Hz) to provide a stimulus between -1.00 D and -3.00 D during trials lasting 40.96 s. There were three illumination conditions: 1. Monochromatic 550 nm light to stimulate long-wavelength-sensitive cones (L-cones) and medium-wavelength-sensitive cones (M-cones) without chromatic aberration; 2. Monochromatic 550 nm light+420 nm light to stimulate long-, medium- and short-wavelength-sensitive cones (S-cones) with longitudinal chromatic aberration (LCA); 3. Monochromatic 550 nm light+420 nm light to stimulate L-, M- and S-cones viewed through an achromatizing lens. In the presence of LCA mean dynamic gain decreased (p=0.0003; ANOVA) and mean accommodation level was reduced (p=0.001; ANOVA). The reduction in gain and increased lag of accommodation in the presence of LCA could result from a blue-yellow chromatic signal or from a larger depth-of-focus.
Kruger
Philip B
PB
Schnurmacher Institute for Vision Research, State College of Optometry, State University of New York, 33 West 42nd Street, New York, NY 10036, USA. pkruger@sunyopt.edu
Rucker
Frances J
FJ
Hu
Caitlin
C
Rutman
Hadassa
H
Schmidt
Nathan W
NW
Roditis
Vasilios
V
D000065:Accommodation, Ocular / Q000502:physiology*; D000328:Adult; D003118:Color Perception / Q000502:physiology*; D006801:Humans; D009907:Optometry / Q000379:methods; D010775:Photic Stimulation / Q000379:methods; D012029:Refraction, Ocular / Q000502:physiology; D017949:Retinal Cone Photoreceptor Cells / Q000502:physiology*