An orientational difference of only 0.3–0.5 deg can be discriminated between two gratings or
two lines, although psychophysical channels and cortical cells both have comparatively …

The difference limen for perceived stimulus orientation was measured for thin lines, and for
sine wave gratings between 2.5 and 20.0 c/deg. All observers exhibited a marked …

An adaptation method is used to determine the orientation specificity of channels sensitive to
different spatial frequencies in the human visual system. Comparison between different …

1. Inspection of a high‐contrast adapting grating produces two visual after‐effects:(a) the
contrast threshold is raised for test gratings of similar spatial frequency to that of the adapting …

We investigated the effect of adaptation on orientation discrimination using two experienced
observers, then replicated the main effects using a total of 50 naı̈ve subjects. Orientation …

The apparent tilt from vertical has been examined for vertical sinusoidal gratings in the
presence of an inducing grating which was tilted 12° from vertical. The amount of apparent …

1. Human visual selectivity for direction of movement was determined using a subthreshold
summation technique. 2. The threshold contrast for detecting a drifting sinusoidal grating …

During adaptation to a high contrast grating it gradually seems to fade. A lower-contrast test
grating appearing directly after the adapting pattern appears reduced in apparent contrast …

Recent data have shown that spatial-frequency adaptation has little effect on spatial-
frequency discrimination at the adapting frequency, but there is a substantial elevation of …

Contrast threshold elevation was measured in human observers at a single spatial
frequency (4 or 8 c/deg) after adaptation to gratings at different contrasts and spatial …