RT Journal Article
SR Electronic
T1 Magnitude-sensitive reaction times reveal non-linear time costs in multi-alternative decision-making
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.05.05.442775
DO 10.1101/2021.05.05.442775
A1 Marshall, James A. R.
A1 Reina, Andreagiovanni
A1 Hay, Célia
A1 Dussutour, Audrey
A1 Pirrone, Angelo
YR 2021
UL http://biorxiv.org/content/early/2021/09/15/2021.05.05.442775.abstract
AB Optimality analysis of value-based decisions in binary and multi-alternative choice settings predicts that reaction times should be sensitive only to differences in stimulus magnitudes, but not to overall absolute stimulus magnitude. Yet experimental work in the binary case has shown magnitude sensitive reaction times, and theory shows that this can be explained by switching from linear to geometric time costs, but also by nonlinear subjective utility. Thus disentangling explanations for observed magnitude sensitive reaction times is difficult. Here for the first time we extend the theoretical analysis of geometric time-discounting to ternary choices, and present novel experimental evidence for magnitude-sensitivity in such decisions, in both humans and slime moulds. We consider the optimal policies for all possible combinations of linear and geometric time costs, and linear and nonlinear utility; interestingly, geometric discounting emerges as the predominant explanation for magnitude sensitivity.Competing Interest StatementThe authors have declared no competing interest.