منابع مشابه
Death rate mystery
Knowing the true rate of death from covid-19 will help us fight the pandemic, but for the moment it eludes us, reports Michael Le Page.
متن کاملT-junctions in inhomogeneous surrounds
In an inhomogeneous checkerboard surround, the lighter check darkens an incremental test patch more than the darker check lightens it. However, decremental test patches are influenced equally [Schirillo & Shevell, 1996. Vision Research, 36, 1783-1796]. In the current study, we manipulate the spatial arrangement of a checkerboard surround to produce T-junctions that perceptually group the checks...
متن کاملHow surrounds affect chromaticity discrimination.
Chromatic discrimination thresholds were measured with and without surrounds along two cardinal axes of chromaticity space. On one axis the level of short-wavelength-sensitive (SWS)-cone excitation was varied for constant long-wavelength-sensitive (LWS)-cone and medium-wavelength-sensitive (MWS)-cone excitations, and on the other axis there were equal and opposite changes in LWS-cone and MWS-co...
متن کاملVisual masking by flickering surrounds.
Observers detected drifting sine-wave gratings presented in a circular 3 dia test field which was surrounded by a 3.25 degrees wide annulus. Forced choice contrast thresholds were measured with surrounds consisting of a steady field of light or uniform sinusoidal flicker. The flickering surround raised detection thresholds only for gratings with spatial frequencies below 2-4 c/deg. Variations o...
متن کاملBrightness contrast from inhomogeneous surrounds
The luminance of a test within an inhomogeneous ("checkerboard") surround was adjusted to match the brightness of a comparison patch within a uniform surround. All stimuli were achromatic. Both surrounds had the same space-averaged luminance. With an incremental comparison patch, a test-within-checkerboard at a luminance between the luminances of the brighter and dimmer checks appears dimmer th...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nature
سال: 2006
ISSN: 0028-0836,1476-4687
DOI: 10.1038/443253a