Related Experiment Videos
The moon illusion: a different view through the legs
1Department of Psychology, University of British Columbia, Vancouver, Canada.
Perceptual and Motor Skills
|December 1, 1992
Summary
Viewing the moon illusion upside down reduces its perceived size. This suggests scene inversion, not just viewing angle, impacts the moon illusion, challenging previous theories.
Area of Science:
- Psychology
- Visual Perception
- Cognitive Science
Background:
- The moon illusion, an overestimation of the horizon moon's size, is often explained by angle of regard and vestibular theories.
- Viewing the moon through one's legs reduces this illusion, supporting these theories.
Purpose of the Study:
- To investigate whether scene inversion, rather than angle of regard or vestibular input, explains the reduction in the moon illusion when viewed through the legs.
- To test the hypothesis that altered depth cue salience due to visual scene inversion contributes to illusion reduction.
Main Methods:
- A sample of 70 subjects participated in the study.
- Participants viewed both normal and inverted pictorial arrays.
- The magnitude of the moon illusion was measured for each condition.
Main Results:
- The moon illusion was significantly reduced when viewing inverted pictorial arrays.
- This finding suggests that scene inversion plays a role in diminishing the illusion's strength.
Conclusions:
- The reduction of the moon illusion when viewed through the legs may be attributed to the alteration of perceived depth associated with scene inversion.
- This challenges explanations solely based on angle of regard or vestibular inputs, highlighting the role of visual scene processing in the moon illusion.