Abstract
Adults can discriminate a 2 – 11% change in spatial frequency (Hirsch & Hylton, 1982; Mayer & Kim, 1986). Purpose. To provide the first measurement of the development of spatial frequency discrimination. Methods. Participants were adults (range: 17–20 yrs, M = 18.9 yrs) and children aged 5, 7, and 9 years (all +/− 3 months; n = 20 per age). Participants saw sequential presentations of a baseline sine-wave grating of 1 or 3 cpd and a comparison sine-wave of higher spatial frequency. The task was to indicate whether the wider stripes occurred in interval 1 or 2. The spatial frequency of the comparison was varied over trials according to a ML-PEST staircase (Harvey, 1986) to measure the minimum spatial frequency discriminable from baseline at 82% correct. Results. An ANOVA showed no significant differences between thresholds at the two baseline spatial frequencies (p [[gt]] .20), significant improvement with age (p p [[gt]] .60). The minimum change from baseline necessary to discriminate spatial frequency decreased from 30.1% in 5-year-olds to 11.6% in 7-year-olds (p p [[gt]] .20). The data were best fit by an exponential function reflecting the rapid improvement in thresholds between 5 and 7 year of age and more gradual improvement thereafter until adulthood (r2 = .046, p Conclusions. The pattern of development for sensitivity to spatial frequency (this study) resembles those for the development of sensitivity to orientation (Lewis et al., 2009) and contrast (Ellemberg et al, 1999). These similar patterns are consistent with theories of common underlying mechanisms (Vincent & Regan, 1995; Zhu et al., 2008). The immaturities at 5 years of age may be caused by higher internal noise.