11:00 - 12:30
Parallel sessions 8
11:00 - 12:30
Room: HSZ - N2
Chair/s:
Jennifer March, Nuno Busch
What do I want to eat, which item do I want to purchase, and in which stocks should I invest? We make countless decisions every day, but our preferences are typically not stable: They often fluctuate strongly across different contexts and depend heavily on our internal states. This symposium aims to shed light on how decisions are affected across different contexts and states. The contribution by Tibor Stöffel will highlight nutrition as an important factor influencing decision-making. In his talk, he disentangles how different macro-nutritional compositions differentially affect the valuation system in the brain, leading to nutrition-dependent levels of loss aversion in risky choice. In the second talk, Nuno Busch reveals that loss aversion in risky decision-making can also be modulated by the degree of explicit information available about the choice options, and by how we learn about them (i.e., from description or from own experience). In the third talk, Jennifer March will present the mechanisms that give rise to contextual influences on food-related decision making. Specifically, she will demonstrate how subjective values of food options and subsequent choice are altered when presented in bundles. In the fourth talk, Barbara Oberbauer will reveal to what extent search patterns differ depending on the decision goal (i.e., choose the most preferred item vs assess the overall value). Moreover, she will show how the possibility of postponing a decision (i.e., choice deferral) affects search patterns and subsequent choice. The effects of goals on choice also play an important role in the final talk of the symposium, wherein Chih-Chung Ting will demonstrate that flexible decision-making relies on goal-dependent value representations. Together, the symposium combines a diverse range of methodologies, including nutritional manipulations, fMRI, eye-tracking, and state-of-the-art cognitive modelling, to illuminate the contextual nature of choice. The symposium features a multi-ethnic team of female and male speakers at different career stages from three universities across two countries offering rich perspectives and expertise in experimental psychology related to human decision-making. 
Submission 567
Nutritional Modulation of Risky Decision Making
SymposiumTalk-01
Presented by: Tibor Stöffel
Tibor Stöffel 1, Jennifer March 2, Sebastian Gluth 2, Tilman Kühn 1, 3, 4, Stefan Schulreich 1
1 University of Vienna, Austria
2 University of Hamburg, Germany
3 Medical University of Vienna, Austria
4 Hochschule Fulda, Germany
In our daily lives, we often have to make decisions in the face of uncertainty. When decisions involve the risk of potential losses, individuals typically weigh losses more heavily than equivalently sized gains – termed loss aversion.

Prior research has indicated that the catecholamines dopamine and noradrenaline, as well as serotonin, play key roles in this process. Since neurotransmitter synthesis depends on dietary precursors, we hypothesized that our daily nutrition would influence loss aversion. Specifically, by varying the macronutrient composition of a single meal, it is possible to modulate circulating levels of large neutral amino acids (LNAAs) such as tyrosine and tryptophan – precursors for catecholamines and serotonin, respectively – and thereby influence neurocognitive functioning.

To test this hypothesis, we collected behavioral data, neuroimaging data, and blood samples from 43 participants (20 female) across two sessions spaced one week apart. In each session, participants consumed one of two isocaloric breakfasts that differed in macronutrient composition (high vs. low carbohydrate-to-protein ratio), designed to shift the balance of tryptophan or tyrosine relative to other LNAAs. Three hours post-meal, participants completed a monetary gambling task with varying potential gains and losses.

We applied a drift diffusion model that dissects loss aversion into multiple computational markers. Our analyses revealed a tyrosine-dependent shift in the starting point bias of the decision process towards accepting the gambles. This suggests that the macronutrient composition of a single meal can influence risky decision-making, adding to growing evidence that nutrition can modulate cognitive processes by altering neurotransmitter precursor availability.