Reward
Brain waves track risk separately from reward value
Open access · cc by · source: Europe PMC
Brain waves that track feedback are strongly influenced by the level of risk a person takes, even when the average expected payoff remains exactly the same.
How this study connects
Role on claims
Each row is a claim on a concept or method page where this paper supports, challenges, or qualifies the statement. Roles are hand-checked — not a model guess.
The outcome signal was conditional on the decision context, not a fixed response to valence.
Outcome-related electrophysiology depends on the choice that preceded it. Feedback-related negativity distinguished gains from losses only when participants had made high-risk choices, and behaviourally participants became more risk-seeking after experiencing losses.
Evidence for the claim as stated.
Late positive brain potentials associated with the P300 family are sensitive to both risk level and feedback valence, exhibiting larger responses for losses compared to gains and overall enhanced amplitudes during high-risk decisions.
Evidence for the claim as stated.
Study at a glance
- Design
- Human experiment — Pilot then main fMRI/EEG of feedback processing in risky decisions
- N
- N=20 · Pilot n = 50 (ages 18–50); main experiment n = 20
- Population
- Healthy adults with no neurological or psychiatric history
- Outcome
- Neural correlates of feedback processing during decision-making under risk
Structured fields used in claim comparison tables when every cited study has a complete layer.
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Brain waves track risk separately from reward value
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50 participants in the pilot experiment
Fifty participants (30 women and 20 men) took part in the pilot experiment.
20 participants in the main experiment
20 participants (five men) attended in the ERP study.
Key findings
Behaviorally, participants were generally risk-averse, preferring low-risk options, but became more risk-seeking after experiencing losses. Electrophysiological recordings revealed that the feedback-related negativity—a brain wave linked to outcome processing—distinguished between gains and losses only when participants made high-risk choices. Additionally, a late positive brain wave was larger for losses compared to gains and was overall enhanced during high-risk choices, reflecting the increased motivational significance of risky outcomes.
Methodology
Researchers designed a two-choice gambling task where participants chose between a low-risk option and a high-risk option. In a pilot study with 50 participants, they analyzed how choices changed based on previous outcomes and overall bank balance. In the main experiment, 20 participants performed hundreds of trials of this task while researchers recorded their brain activity using electroencephalography.
Limitations
First, because the probability of winning was kept high to mimic typical decision environments, the study confounded feedback valence with frequency, meaning positive feedback occurred more often than negative feedback. Second, the small sample size of 20 participants in the brain-imaging portion limits the generalizability of the brain-behavior correlations. Lastly, the study could not separate the impact of the actual size of the outcome from the brain's calculation of reward prediction errors, meaning further research is needed to isolate these factors.
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