At what frame rate does the brain begin to lose awareness of the interval between images and perceive apparent motion?

• A. 8 fps
• B. 12 fps
• C. 10 fps
• D. 24 fps

Answer: (C)

Apparent motion comes from the brain blending successive images shown in quick succession. This relies on temporal integration and persistence of vision. Around 0.1 seconds per frame (10 frames per second), consecutive images occur within the brain’s integration window, so the gap between frames isn’t noticed and the sequence reads as smooth movement. Lower frame rates, like 8 fps, still feel choppier with visible gaps, while higher rates such as 12 or 24 fps produce motion that’s even smoother. The threshold where the interval starts to fade from perception and motion appears is best represented by 10 fps.