How do we decide what to eat? In humans, the reward value derived from sensory and nutritional food components motivates sophisticated forms of eating behaviour, including consumption-planning, decision-making, and social influences on food choice. Specific nutrients—such as fats, sugars, and their sensory qualities—are particularly effective rewards that drive such behaviours and contribute to overeating and obesity. Because neurons in the brain’s reward system set the goals for behaviour, we aim to understand how such reward neurons process specific food components to guide planning and decision-making. We focus on the amygdala, a key component of the reward system that is implicated in such diverse conditions as depression, autism, and obesity. Our recent data indicate that beyond basic reward functions, amygdala neurons participate in advanced reward-guided behaviours, including economic decision-making and social learning.
We study the mechanisms for eating behaviour and reward-based decisions in both individual neurons and functional brain systems. We conduct single-neuron recordings in animals performing behavioural tasks for nutrient-defined food rewards. These experiments identify the precise information processing by neurons in key reward structures, including the amygdala. In parallel, we conduct closely related human neuroimaging studies to translate and extend the single-neuron data to human brain systems, real-life eating phenotypes, and inter-individual differences. Our work benefits from collaborations with experimental and computational neuroscientists in Cambridge and abroad, in particular the group of Professor Wolfram Schultz at the Department of Physiology, Development and Neuroscience, with which we are associated, and with Professors Sadaf Farooqi and Paul Fletcher at the IMS. Our broader goal is to uncover basic neurophysiological reward mechanisms that underlie human eating behaviour and thereby to lay foundations for clinical studies in obesity.
Grabenhorst, F., Baez-Mendoza, R., Genest, W.A.M., Deco, G. and Schultz, W. (2019). Primate amygdala neurons simulate decision processes of social partners. Cell, 177, 986-998. PMID: 30982599
Rosenthal-von der Pütten, A. Krämer, C.C., Maderwald, S., Brand, M. and Grabenhorst, F. (2019). Neural Mechanisms for Accepting and Rejecting Artificial Social Partners in the Uncanny Valley. Journal of Neuroscience, 39, 6555-6570. PMID: 31263064
Grabenhorst, F.*, Tsutsui K.*, Kobayashi S. and Schultz, W. (2019). Primate prefrontal neurons signal economic risk derived from the statistics of recent reward experience. eLife. pii: e44838. (*Joint first authors). PMID: 31343407
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Grabenhorst F, Schulte FP, Maderwald S, Brand M (2013), “Food labels promote healthy choices by a decision bias in the amygdala.” Neuroimage 74:152-63
Grabenhorst F, Rolls ET (2011), “Value, pleasure and choice in the ventral prefrontal cortex.” Trends Cogn Sci 15(2):56-67.
Grabenhorst F, Rolls ET, Parris BA, d’Souza AA (2010), “How the brain represents the reward value of fat in the mouth.” Cereb Cortex 20(5):1082-91.
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