What best describes stereopsis?

What best describes stereopsis?

• A. Color perception under binocular viewing.
• B. Depth perception from monocular cues only.
• C. Depth perception arising from binocular disparity and proper alignment.
• D. Motion parallax as the sole cue for depth.

Answer: (C)

Stereopsis is the depth perception that arises when both eyes view the same scene and the brain fuses two slightly different images into a single, three-dimensional view. This relies on binocular disparity—the tiny differences between the two retinal images—and on the eyes being properly aligned so those disparities can be used to judge depth. When the eyes are well-aligned and able to fuse the images, small disparities provide precise depth information, especially for nearby objects. If alignment is off or fusion is impaired (as in strabismus or significant anisometropia), disparity signals weaken and stereo depth perception suffers. Other options describe cues that don’t define stereopsis. Color perception under binocular viewing is about color, not depth. Depth from monocular cues relies on information available to one eye, not the binocular disparity mechanism. Motion parallax is a depth cue that can work with one eye and isn’t the binocular disparity-based process central to stereopsis.

Stereopsis is the depth perception that arises when both eyes view the same scene and the brain fuses two slightly different images into a single, three-dimensional view. This relies on binocular disparity—the tiny differences between the two retinal images—and on the eyes being properly aligned so those disparities can be used to judge depth. When the eyes are well-aligned and able to fuse the images, small disparities provide precise depth information, especially for nearby objects. If alignment is off or fusion is impaired (as in strabismus or significant anisometropia), disparity signals weaken and stereo depth perception suffers.

Other options describe cues that don’t define stereopsis. Color perception under binocular viewing is about color, not depth. Depth from monocular cues relies on information available to one eye, not the binocular disparity mechanism. Motion parallax is a depth cue that can work with one eye and isn’t the binocular disparity-based process central to stereopsis.