Binocular Summation
Binocular summation means that the detection threshold for a stimulus is lower with two eyes than with one. There are two forms. First, when trying to detect a faint signal, there is a statistical advantage of using two detectors over using one. Mathematically, the advantage is equal to the square root of 2, about 1.41. Second, when some cells in the visual cortex receive input from both eyes simultaneously, they show binocular facilitation, a greater level of activity than the sum of the two activities evoked separately from each eye. Any advantage in using two eyes in detection task over 1.41 is credited to this sort of mechanism, dubbed neural summation.
Read more about this topic: Binocular Vision
Famous quotes containing the word summation:
“He maintained that the case was lost or won by the time the final juror had been sworn in; his summation was set in his mind before the first witness was called. It was all in the orchestration, he claimed: in knowing how and where to pitch each and every particular argument; who to intimidate; who to trust, who to flatter and court; who to challenge; when to underplay and exactly when to let out all the stops.”
—Dorothy Uhnak (b. 1933)