An enhanced perception of difference between 2 stimuli when they are presented close to each other. See colour contrast; contrast illusion; Mach bands. For understanding, you can compare it with successive contrast.

SIMULTANEOUS CONTRAST: "In simultaneous contrast we can tell between 2 closely spaced stimuli."
Cite this page: N., Pam M.S., "SIMULTANEOUS CONTRAST," in, April 13, 2013, (accessed April 22, 2021).