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The online processing of dynamics
Abdul-Rahim Deeb1, Alexander Fengler2, Fulvio Domini2
1Department of Cognitive Science, Johns Hopkins University, Baltimore, MD, USA.
The visual system jointly estimates object mass and velocity using the Online Processing of Dynamics Model (OPoD). This model reveals how perceived mass influences velocity judgments and vice versa, offering a unified account of dynamic scene perception.
Area of Science:
- Visual perception
- Cognitive neuroscience
- Physics perception
Background:
- Estimating object mass and velocity is crucial for navigating dynamic environments.
- Previous models often treat mass and velocity estimation separately, lacking a unified mechanism.
Purpose of the Study:
- Introduce and validate the Online Processing of Dynamics Model (OPoD) for visual mass estimation.
- Investigate the joint and reciprocal influence of mass and velocity perception.
Main Methods:
- Developed the OPoD model, positing joint encoding of mass and velocity in a shared representation.
- Conducted three experiments to test OPoD's predictions regarding mutual biases between mass and velocity perception.
- Compared OPoD's performance against an adapted noisy Newton model.
Main Results:
- Empirically confirmed that initial mass impressions bias perceived post-collision velocity.
- Demonstrated that velocity biases subsequently influence relative mass judgments.
- OPoD provided superior quantitative fits compared to the noisy Newton model.
Conclusions:
- Mass and velocity are jointly encoded and mutually constraining within a momentum-like representation.
- OPoD offers a mechanistic explanation for integrated physical expectations in dynamic scene perception.
- The model provides an ecologically grounded complement to probabilistic frameworks.
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