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Updated: May 3, 2026
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Published on: May 7, 2019
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Semantic control of feature extraction from natural scenes
1Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, United Kingdom, Laboratoire des Systèmes Perceptifs, CNRS UMR 8248, and Département d'études cognitives, Ecole normale supérieure, 75005, Paris, France.
Summary
Higher brain functions influence early visual processing. Semantic manipulation of scenes reshaped low-level feature detection, showing top-down control in visual perception.
Area of Science:
- Neuroscience
- Cognitive Science
- Computer Vision
Background:
- The human visual system processes scenes hierarchically, from local features to semantic understanding.
- It remains unclear if higher-level semantic information influences early visual cortex processing.
Purpose of the Study:
- To investigate top-down influences of semantic scene interpretation on early visual feature processing.
- To provide evidence for or against feedback mechanisms in the human visual system.
Main Methods:
- Developed a novel paradigm embedding low-level orientation probes within natural scenes.
- Disrupted semantic interpretation via stimulus inversion and reversed playback.
- Measured orientation tuning of probe discrimination under varying semantic conditions.
Main Results:
- Orientation tuning of low-level feature detection was significantly altered by semantic manipulation.
- Demonstrated that higher-level semantic modules exert partial control over early visual processes.
Conclusions:
- Early visual processing is not purely feedforward but is modulated by top-down semantic context.
- This top-down control may function as a predictive strategy, refining local reconstruction based on global scene meaning.
- Findings offer insights into phenomena like the face inversion effect.
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