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A Two-interval Forced-choice Task for Multisensory Comparisons
Published on: November 9, 2018
Bayesian priors are encoded independently from likelihoods in human multisensory perception
Ulrik R Beierholm1, Steven R Quartz, Ladan Shams
1Gatsby Computational Neuroscience Unit, UCL, London, UK. beierh@gatsby.ucl.ac.uk
Journal of Vision
|September 18, 2009
Summary
This study investigated Bayesian computation in humans. Results show that prior probabilities in Bayesian models are independent of immediate sensory input, supporting stable internal representations.
Area of Science:
- Cognitive science
- Computational neuroscience
- Bayesian modeling
Background:
- Human crossmodal information combination aligns with optimal Bayesian causal inference.
- Bayesian priors are intuitively considered independent of current stimuli.
- The invariance of priors to varying likelihoods in Bayesian computation remains empirically unaddressed.
Purpose of the Study:
- To empirically investigate whether prior probabilities in Bayesian models are independent of likelihoods.
- To examine the stability of priors when faced with significantly altered stimulus information.
Main Methods:
- Manipulation of presumed likelihoods using two distinct sets of stimuli.
- Estimation of prior probabilities under different likelihood conditions.
- Empirical investigation of prior-stimulus independence.
Main Results:
- Estimated prior probabilities were found to be independent of the immediate sensory input (likelihoods).
- This independence suggests that priors remain stable despite changes in stimulus characteristics.
- Findings support the notion of stable internal representations in Bayesian inference.
Conclusions:
- The study provides empirical evidence for the independence of priors from likelihoods in human Bayesian computation.
- This supports a key characteristic of Bayesian models where priors are not influenced by immediate sensory data.
- Results clarify computational principles in crossmodal integration and segregation.
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