From brainstem arousal to cortical prediction: A circuit-based framework for active flavor inference
Yong-Shin Hong1, Young-Seok Park1
1Department of Oral Anatomy and Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Republic of Korea.
Brain Research Bulletin
|May 16, 2026
Summary
Flavor perception is an active process where the brain integrates sensory input with internal states, not just a passive relay. This Active Flavor Inference (AFI) model explains how taste experiences change based on context and physiology.
Area of Science:
- Neuroscience
- Sensory Processing
- Computational Biology
Background:
- Current taste processing models struggle to explain subjective flavor variability.
- Traditional models focus on bottom-up sensory pathways, neglecting physiological and contextual influences.
Purpose of the Study:
- Propose Active Flavor Inference (AFI) as a new framework for gustatory processing.
- Reinterpret flavor perception through predictive coding and interoceptive regulation.
- Explain state-dependent flavor distortions.
Main Methods:
- Synthesize evidence from animal models and human neuroimaging.
- Conceptualize flavor perception as an active inferential process.
- Propose functional interactions among brainstem, thalamic, and cortical networks.
Main Results:
- Flavor perception arises from integrating sensory evidence, physiological state, and predictions.
- Gustatory processing involves distributed architectures, not just linear pathways.
- Ascending sensory signals and descending regulatory influences converge.
Conclusions:
- Active Flavor Inference (AFI) offers a structured framework for understanding flavor perception.
- The AFI model accounts for variability in flavor experiences.
- This framework generates testable predictions for future gustatory research.
Keywords:
Active flavor inferenceBrainstem arousalFlavor perceptionGatingGustationInsular cortexInteroceptionPredictive processingThalamicMore Related Videos
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