Summary: Researchers have identified a specific brain region in rats that plays a decisive role in economic choices under uncertainty, revealing how value is represented when animals face lottery-like decisions.
The frontal orienting field (FOF) emerged as a principal site that encodes the value of risky options, while the posterior parietal cortex (PPC) showed only a minor and transient influence.
This work advances our understanding of the neural mechanisms that underlie risky financial choices and provides a model for studying decision-making under economic uncertainty.
Key Facts:
- The study establishes a rodent model of economic decision-making that captures uncertainty similar to human financial choices.
- Temporary silencing of the frontal orienting field (FOF) made rats less inclined to gamble, reducing their risk tolerance.
- The FOF dynamically represents the lottery’s value and evaluates it against a fixed, guaranteed reward (the surebet), guiding choice.
Source: Sainsbury Wellcome Center
Neuroscientists have located a critical brain area in rats that dynamically encodes the value of choices when outcomes are uncertain. This study is the first to causally test the roles of frontal and parietal cortical areas in economic decision-making and lays groundwork for mapping the neural circuit of risky choice.
“Economic decisions shape our lives, especially in times of financial instability. People deciding whether to invest or to choose safer options face uncertainty,” said Jeffrey Erlich, Group Leader at the Sainsbury Wellcome Centre and corresponding author of the study. “We developed a rodent task that mimics these economic dilemmas so we can trace how the brain evaluates risk.”
In the experiment, rats repeatedly chose between a guaranteed small reward (the surebet) and a cued lottery with a fixed probability. Each trial presented a sound indicating the magnitude of the possible lottery payoff. Six distinct tones mapped to different lottery magnitudes, including an offer of zero as a control baseline—rats should never choose a lottery that promised no reward, allowing researchers to separate offer-dependent valuation from persistent choice biases.
To test causality, the team temporarily silenced two cortical regions known to be involved in decision-making: the frontal orienting field (FOF) and the posterior parietal cortex (PPC). Both pharmacological and optogenetic techniques were employed to confirm the effects of inactivation.
Results showed a marked reduction in risky choices when the FOF was silenced, while PPC inactivation produced only a modest and short-lived effect. Detailed modeling using a Bayesian hierarchical framework revealed that FOF silencing altered the rats’ risk tolerance rather than producing a simple side or choice bias: rats continued to choose the lottery when its potential reward was very large, but they avoided lotteries with intermediate expected value.
Behavior for low-value lotteries remained unchanged, consistent with expectations when offers are clearly dominated by the surebet.
To explain these findings, the researchers developed a dynamical model in which the FOF represents the trial-by-trial value of the lottery and compares it to the remembered, stable value of the surebet. Inactivation reduces the encoded value of the lottery while leaving the surebet representation intact, shifting choices toward the guaranteed reward—especially for offers near the decision boundary where lottery and surebet values are close.
Electrophysiological recordings supported the model: single neurons and population activity in the FOF encoded lottery value on a per-trial basis. The model and recordings together indicate that the FOF is a critical node for dynamically representing action values in choices under risk.
Future work will trace the inputs and outputs of the FOF to map the broader circuit and will introduce a multi-stage version of the task with an additional cue. This extension will help reveal how value-based decisions are transformed into actions across time.
Funding: This research was supported by the 111 project (Base B16018), the National Natural Science Foundation of China (NSFC), the NYU-ECNU Institute of Brain and Cognitive Science at NYU Shanghai, and the funders of the Sainsbury Wellcome Centre: Gatsby Charitable Foundation and Wellcome.
About this neuroscience research news
Author: April Cashin-Garbutt
Source: Sainsbury Wellcome Center
Contact: April Cashin-Garbutt – Sainsbury Wellcome Center
Image: The image is credited to Neuroscience News
Original Research: Open access.
“The rat frontal orienting field dynamically encodes value for economic decisions under risk” by Jeffrey Erlich et al. Nature Neuroscience
Abstract
The rat frontal orienting field dynamically encodes value for economic decisions under risk
Frontal and parietal cortex are implicated in economic decision-making, but their causal roles have not been directly tested until now. In this study, researchers silenced the frontal orienting field (FOF) and the posterior parietal cortex (PPC) while rats chose between a cued lottery and a stable, small surebet. PPC inactivations produced minimal, short-lived effects, whereas FOF inactivations reliably reduced lottery choices.
A mixed-agent model of choice indicated that silencing the FOF altered the curvature of the rats’ utility function (U = V^ρ), consistent with a change in risk attitude. Electrophysiological analyses showed that individual FOF neurons and population activity encode the trial-by-trial value of the lottery. A dynamical model that accounts for both neural activity and silencing effects suggests the FOF represents the current lottery value for comparison against the remembered surebet value.
These results demonstrate that the FOF is a key node within the neural circuit that dynamically represents action values during choices under risk, illuminating how transient changes in neural encoding can shift economic preferences.