Effect of extending grating length and width on human visually evoked potentials.

Visually evoked potentials (VEPs) were elicited by Gabor gratings with different lengths and widths at three spatial frequencies (SFs): low, 1.45 c/deg, medium, 2.9 c/deg and high, 5.

How many pathways determine the speed of grating detection?

Reaction time (RT) for detection of gratings of different spatial frequencies (SF, 0.87-13.87 c/d) and contrast (2-32 times above the detection threshold) was measured.