A covariance structure analysis of flicker sensitivity.
We tested whether linear structural models of the mechanisms underlying flicker sensitivity could reproduce the variance-covariance matrix of temporal contrast sensitivity data. Monocular sensitivities to frequencies between 2.5 and 45 Hz were measured for 124 subjects, ages 18-88 yr. Exploratory factor analyses revealed that both a two-mechanism and a three-mechanism model could adequately account for the data. Furthermore, confirmatory factor analyses and full structural equation models, using age as an explanatory variable, supported both models, with the three-factor model giving a somewhat better representation of the data. Parsimony favors the two-mechanism model. But patterns of loss associated with pre-exudative age-related maculopathy are more easily understood in terms of three underlying mechanisms.
Mayer
M J
MJ
Psychology Department, University of California, Santa Cruz 95064, USA.
Dougherty
R F
RF
Hu
L T
LT
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D015350:Contrast Sensitivity / Q000502:physiology*; D005425:Flicker Fusion / Q000502:physiology*; D006801:Humans; D008268:Macular Degeneration / Q000523:psychology; D008875:Middle Aged; D008960:Models, Psychological; D015349:Vision, Monocular / Q000502:physiology