Spatial frequency tuning functions and contrast sensitivity at different eccentricities in the visual field
The human luminance spatial frequency contrast sensitivity function (CSF) has been well studied using psychophysical measurements by detecting spatial frequency (SF) grating patterns at threshold. Threshold CSFs at different eccentricities have proven to be quite useful in both basic and clinical vision research. However, near threshold, the CSF is measured at a linear area of the saturating contrast-response curve. In contrast, most of our everyday vision may be at suprathreshold levels, and thus may function most of the time at the nonlinear area of the contrast-response curve. In this study, in order to better characterize the CSF at normal contrast levels, we measured the SF tuning functions as well as the CR functions at different suprathreshold contrast levels and different eccentricities of the visual field using noninvasive MEG techniques. In this study, in addition to peak analysis, we have developed more reliable averaged power analysis methods where the average power can be calculated from the entire waveforms.
- Research Organization:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- National Eye Inst., Bethesda, MD (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 285436
- Report Number(s):
- LA-UR-96-1911; CONF-9602101-4; ON: DE96012617
- Resource Relation:
- Conference: Biomagnetism conference, Santa Fe, NM (United States), Feb 1996; Other Information: PBD: [1996]
- Country of Publication:
- United States
- Language:
- English
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