Abstract
Intuition and an assumption of basic rationality would suggest that people evaluate a stimulus on the basis of its properties and their underlying utility. However, various findings suggest that evaluations often depend not only on the thing evaluated, but also on a variety of contextual factors. Here we demonstrate a further departure from normative decision making: Aesthetic evaluations of abstract fractal art by human subjects were predicted with up to 75% accuracy by their brain states before the stimuli were presented. These predictions were based on cross-validation tests of pre-stimulus patterns of BOLD fMRI signals across a distributed network of regions in the frontal lobes. This predictive power did not simply reflect motor biases in favor of pressing a particular button. Our findings suggest that endogenous neural signals that exist before trial onset can bias people's decisions when evaluating visual stimuli.