TY - JOUR

T1 - Base rate neglect and neural computations for subjective weight in decision under uncertainty

AU - Yang, Yun Yen

AU - Wu, Shih Wei

N1 - Publisher Copyright:
© 2020 National Academy of Sciences. All rights reserved.

PY - 2020/7/21

Y1 - 2020/7/21

N2 - Base rate neglect, an important bias in estimating probability of uncertain events, describes humans' tendency to underweight base rate (prior) relative to individuating information (likelihood). However, the neural mechanisms that give rise to this bias remain elusive. In this study, subjects chose between uncertain prospects where estimating reward probability was essential. We found that when the variability of prior and likelihood information about reward probability were systematically manipulated, prior variability significantly affected the degree to which subjects underweight the base rate of reward probability. Activity in the orbitofrontal cortex, medial prefrontal cortex, and putamen represented the relative subjective weight that reflected such bias. Further, sensitivity to likelihood relative to prior variability in the putamen correlated with individuals' overall tendency to underweight base rate. These findings suggest that in combining prior and likelihood, relative sensitivity to information variability and subjective-weight computations critically contribute to the individual heterogeneity in base rate neglect.

AB - Base rate neglect, an important bias in estimating probability of uncertain events, describes humans' tendency to underweight base rate (prior) relative to individuating information (likelihood). However, the neural mechanisms that give rise to this bias remain elusive. In this study, subjects chose between uncertain prospects where estimating reward probability was essential. We found that when the variability of prior and likelihood information about reward probability were systematically manipulated, prior variability significantly affected the degree to which subjects underweight the base rate of reward probability. Activity in the orbitofrontal cortex, medial prefrontal cortex, and putamen represented the relative subjective weight that reflected such bias. Further, sensitivity to likelihood relative to prior variability in the putamen correlated with individuals' overall tendency to underweight base rate. These findings suggest that in combining prior and likelihood, relative sensitivity to information variability and subjective-weight computations critically contribute to the individual heterogeneity in base rate neglect.

KW - Base rate neglect

KW - Medial prefrontal cortex

KW - Orbitofrontal cortex

KW - Probabilistic inference

KW - Putamen

UR - http://www.scopus.com/inward/record.url?scp=85088879390&partnerID=8YFLogxK

U2 - 10.1073/pnas.1912378117

DO - 10.1073/pnas.1912378117

M3 - Article

C2 - 32616568

AN - SCOPUS:85088879390

SN - 0027-8424

VL - 117

SP - 16908

EP - 16919

JO - Proceedings of the National Academy of Sciences of the United States of America

JF - Proceedings of the National Academy of Sciences of the United States of America

IS - 29

ER -