title: Similar neural mechanisms for perceptual guesses and free decisions.
abstract: When facing perceptual choices under challenging conditions we might believe to be purely guessing. But which brain regions determine the outcome of our guesses? One possibility is that higher-level, domain-general brain regions might help break the symmetry between equal-appearing choices. Here we directly investigated whether perceptual guesses share brain networks with other types of free decisions. We trained an fMRI-based pattern classifier to distinguish between two perceptual guesses and tested whether it was able to predict the outcome of similar non-perceptual choices, as in conventional free choice tasks. Activation patterns in the medial posterior parietal cortex cross-predicted free decisions from perceptual guesses and vice versa. This inter-changeability strongly speaks for a similar neural code for both types of decisions. The posterior parietal cortex might be part of a domain-general system that helps resolve decision conflicts when no choice option is more or less likely or valuable, thus preventing behavioural stalemate.
authors.affiliation: Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstrasse 1A, 04109 Leipzig, Germany. sbode@unimelb.edu.au
authors.forename: Stefan
authors.initials: S
authors.lastname: Bode
authors.forename: Carsten
authors.initials: C
authors.lastname: Bogler
authors.forename: John-Dylan
authors.initials: JD
authors.lastname: Haynes
mesh_terms: D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D003657:Decision Making / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging