Which illusion is described as the movement of a stationary light perceived during darkness (Autokinesis)?

Which illusion is described as the movement of a stationary light perceived during darkness (Autokinesis)?

• A. Autokinesis
• B. Induced Motion
• C. Structural Illusion
• D. Size/Distance Illusion

Answer: (A)

In darkness with few visual references, a stationary light can appear to drift due to autokinesis. Tiny involuntary eye movements create movement on the retina when there’s nothing nearby to anchor the image, and the brain interprets that as the light moving even though it isn’t. This is a common night-flight cue when staring at a single light source; the effect can be reduced by shifting your gaze to another object or the horizon reference, or by taking brief glances away from the light. This illusion is distinct from Induced Motion, where a moving background or observer makes another object seem to move, and from Size/Distance or Structural Illusions, which involve misperceptions of distance, size, or cues from the cockpit environment rather than motion of a stationary light.

In darkness with few visual references, a stationary light can appear to drift due to autokinesis. Tiny involuntary eye movements create movement on the retina when there’s nothing nearby to anchor the image, and the brain interprets that as the light moving even though it isn’t. This is a common night-flight cue when staring at a single light source; the effect can be reduced by shifting your gaze to another object or the horizon reference, or by taking brief glances away from the light. This illusion is distinct from Induced Motion, where a moving background or observer makes another object seem to move, and from Size/Distance or Structural Illusions, which involve misperceptions of distance, size, or cues from the cockpit environment rather than motion of a stationary light.