Adaptive Prediction Error Coding in the Human Midbrain and Striatum Facilitates Behavioral Adaptation and Learning Efficiency

TY - JOUR

T1 - Adaptive Prediction Error Coding in the Human Midbrain and Striatum Facilitates Behavioral Adaptation and Learning Efficiency

AU - Diederen, Kelly M J

AU - Spencer, Tom

AU - Vestergaard, Martin D

AU - Fletcher, Paul C

AU - Schultz, Wolfram

N1 - Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

PY - 2016/6/1

Y1 - 2016/6/1

N2 - Effective error-driven learning benefits from scaling of prediction errors to reward variability. Such behavioral adaptation may be facilitated by neurons coding prediction errors relative to the standard deviation (SD) of reward distributions. To investigate this hypothesis, we required participants to predict the magnitude of upcoming reward drawn from distributions with different SDs. After each prediction, participants received a reward, yielding trial-by-trial prediction errors. In line with the notion of adaptive coding, BOLD response slopes in the Substantia Nigra/Ventral Tegmental Area (SN/VTA) and ventral striatum were steeper for prediction errors occurring in distributions with smaller SDs. SN/VTA adaptation was not instantaneous but developed across trials. Adaptive prediction error coding was paralleled by behavioral adaptation, as reflected by SD-dependent changes in learning rate. Crucially, increased SN/VTA and ventral striatal adaptation was related to improved task performance. These results suggest that adaptive coding facilitates behavioral adaptation and supports efficient learning.

AB - Effective error-driven learning benefits from scaling of prediction errors to reward variability. Such behavioral adaptation may be facilitated by neurons coding prediction errors relative to the standard deviation (SD) of reward distributions. To investigate this hypothesis, we required participants to predict the magnitude of upcoming reward drawn from distributions with different SDs. After each prediction, participants received a reward, yielding trial-by-trial prediction errors. In line with the notion of adaptive coding, BOLD response slopes in the Substantia Nigra/Ventral Tegmental Area (SN/VTA) and ventral striatum were steeper for prediction errors occurring in distributions with smaller SDs. SN/VTA adaptation was not instantaneous but developed across trials. Adaptive prediction error coding was paralleled by behavioral adaptation, as reflected by SD-dependent changes in learning rate. Crucially, increased SN/VTA and ventral striatal adaptation was related to improved task performance. These results suggest that adaptive coding facilitates behavioral adaptation and supports efficient learning.

KW - Adaptation, Psychological

KW - Corpus Striatum

KW - Humans

KW - Learning

KW - Magnetic Resonance Imaging

KW - Models, Psychological

KW - Neuroimaging

KW - Neurons

KW - Psychomotor Performance

KW - Reward

KW - Substantia Nigra

KW - Ventral Tegmental Area

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1016/j.neuron.2016.04.019

DO - 10.1016/j.neuron.2016.04.019

M3 - Article

C2 - 27181060

SN - 0896-6273

VL - 90

SP - 1127

EP - 1138

JO - Neuron

JF - Neuron

IS - 5

ER -