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Updated: Jul 6, 2026
11:16
A Novel Procedure for Evaluating the Reinforcing Properties of Tastants in Laboratory Rats: Operant Intraoral Self-administration
Published on: February 6, 2014
Tasteless food reward
Zane B Andrews1, Tamas L Horvath
1Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06519, USA.
Neuron
|March 28, 2008
Summary
Calorie load, not taste, can activate the brain's reward system. Mice lacking sweet taste receptors still preferred sugar, showing the power of postingestive signals.
Area of Science:
- Neuroscience
- Sensory Biology
- Metabolic Regulation
Background:
- Food palatability influences the dopaminergic reward system, often overriding energy needs.
- The role of postingestive factors, independent of taste, in modulating this system is not well understood.
Discussion:
- This study investigates how postingestive calorie sensing impacts the mesolimbic dopamine-accumbal pathway.
- Researchers utilized Trpm5 knockout mice, which lack functional sweet taste receptors, to isolate the effect of calorie load.
Key Insights:
- Mice without sweet taste perception developed a preference for sucrose based solely on its calorie content.
- This preference was mediated by the activation of the mesolimbic dopamine-accumbal pathway, demonstrating a taste-independent reward mechanism.
- Postingestive nutrient sensing can directly influence reward pathway activation.
Outlook:
- Further research could explore the specific nutrient sensors involved in this calorie-based reward.
- Understanding these pathways may offer new strategies for managing appetite and metabolic disorders.
- Investigating the integration of taste and postingestive signals in reward processing is crucial.
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