If you focus on your fingertip and bring it toward your eyes until they almost cross, you will actually feel convergence.However, if you close one eye, you will not feel an increase in muscle tension as your finger gets closer because convergence
A)has habituated.
B)is a binocular depth cue.
C)overlap has occurred.
D)retinal disparity will compensate when one eye is closed.

Question

Quizplus · Accepted Answer

Convergence is a binocular depth cue that requires input from both eyes to create the feeling of tension or strain as an object moves closer to the face. When one eye is closed, the brain cannot compare the images from both eyes and therefore cannot create the sensation of convergence.

If You Focus on Your Fingertip and Bring It Toward