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Published on: April 16, 2014
Background Surface and Horizon Effects in the Perception of Relative Size and Distance
Kerem Ozkan1, Myron L Braunstein
1University of California, Irvine, CA, USA.
Visual Cognition
|September 4, 2010
Summary
Object height perception changes above the horizon. Higher objects appear larger below the horizon but smaller above it, impacting perceived size and distance judgments.
Area of Science:
- Visual perception
- Psychophysics
- Environmental psychology
Background:
- Object height influences perceived size and distance.
- This effect is expected to change when objects are positioned above the horizon.
Purpose of the Study:
- To investigate how object height relative to the horizon affects perceived size and distance.
- To examine the reversal of size-distance relationships for objects above the horizon.
Main Methods:
- Four experiments were conducted using paired objects of varying heights.
- Observers judged relative size and relative distance of these objects.
- Stimuli manipulated object height relative to the perceptual horizon.
Main Results:
- Objects equal in projected size were perceived as larger when below the horizon.
- This size perception reversed when objects were at or above the horizon.
- Higher objects were consistently perceived as more distant, irrespective of their position relative to the horizon.
Conclusions:
- Perceived size is influenced by object height relative to the horizon, with a reversal occurring above the horizon.
- Perceived distance is primarily determined by object height, with higher objects appearing more distant.
- The relationship between perceived size and distance reverses for objects above the horizon.
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