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Published on: August 30, 2013
Form discrimination: features or invariants?
G J Smets1, P J Stappers, B J Kröse
1Delft University of Technology, The Netherlands.
Perceptual and Motor Skills
|August 1, 1988
Summary
Form discrimination depends on behavioral relevance, not just features. Direct perception theory suggests we recognize meaningful patterns, supporting this finding that disruptive targets were identified more easily.
Area of Science:
- Cognitive Psychology
- Visual Perception
Background:
- Theories of perception debate whether form discrimination relies on analyzing features or recognizing behaviorally relevant affordances.
- Indirect theory posits feature analysis, while direct theory emphasizes invariant patterns specifying meaning.
Purpose of the Study:
- To investigate whether form discrimination is based on feature analysis or affordances.
- To test predictions of direct versus indirect theories of perception.
Main Methods:
- Participants identified the position of a target in a perspective plane rendering.
- Stimuli were displayed briefly (100 msec) under conditions where the target either disrupted or did not disrupt the plane.
- Target features were consistent across conditions.
Main Results:
- Disruptive targets were discriminated significantly more often than non-disruptive targets.
- This occurred despite targets sharing identical features across conditions.
- Performance differences were linked to the behavioral relevance of the disruption.
Conclusions:
- Results support the direct approach to perception.
- Perceivers discriminate behaviorally relevant patterns over mere geometrical properties.
- Affordances, as specified by invariant patterns, play a crucial role in form discrimination.
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