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Do reference surfaces influence exocentric pointing?
M J A Doumen1, A M L Kappers, J J Koenderink
1Universiteit Utrecht, Helmholtz Instituut, Physics of Man, Utrecht, The Netherlands.
Acta Psychologica
|April 22, 2008
Summary
Visual scene elements influence egocentric distance perception. This study found poster-boards only affected exocentric direction perception when used as direct references for pointing tasks.
Area of Science:
- Visual perception
- Spatial cognition
- Human-computer interaction
Background:
- Egocentric distance perception is influenced by various visual scene elements.
- The impact of scene elements on exocentric direction perception is less understood.
Purpose of the Study:
- To investigate if visual scene elements, specifically poster-boards, influence exocentric direction perception.
- To determine the conditions under which poster-boards affect exocentric direction estimation.
Main Methods:
- An exocentric pointing task was employed.
- Participants used a remote-controlled pointer to align with a target.
- Poster-boards were strategically placed in the visual field to assess their influence.
Main Results:
- Poster-boards influenced exocentric direction perception.
- This influence was contingent on the poster-boards serving as direct references for the pointing task.
Conclusions:
- Visual scene context plays a role in exocentric direction perception, similar to egocentric distance.
- The functional role of contextual elements as references is critical for their impact on spatial judgments.
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