RT Journal Article
SR Electronic
T1 Affective Bias as a Rational Response to the Statistics of Rewards and Punishments
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 114991
DO 10.1101/114991
A1 Erdem Pulcu
A1 Michael Browning
YR 2017
UL http://biorxiv.org/content/early/2017/04/11/114991.abstract
AB Affective bias, the tendency to prioritise the processing of negative relative to positive events, is causally linked to clinical depression. However, why such biases develop or how they may best be ameliorated is not known. Using a computational framework, we investigated whether affective biases may reflect an individual’s estimates of the information content of negative and positive events. During a reinforcement learning task, the information content of positive and negative outcomes was manipulated independently by varying the volatility of their occurrence. Human participants altered the learning rates used for the outcomes selectively, preferentially learning from the most informative. This behaviour was associated with activity of the central norepinephrine system, estimated using pupilometry, for loss outcomes. Humans maintain independent estimates of the information content of positive and negative outcomes which bias their processing of affective events. Normalising affective biases using computationally inspired interventions may represent a novel treatment approach for depression.