Brain-based mechanisms underlying complex causal thinking.

We use functional magnetic resonance imaging (fMRI) and behavioral analyses to study the neural roots of biases in causal reasoning. Fourteen participants were given a task requiring them to interpret data relative to plausible and implausible causal theories. Encountering covariation-based data during the evaluation of a plausible theory as opposed to an implausible theory selectively recruited neural tissue in the prefrontal and occipital cortices. In addition, the plausibility of a causal theory modulated the recruitment of distinct neural tissue depending on the extent to which the data were consistent versus inconsistent with the theory provided. Specifically, evaluation of data consistent with a plausible causal theory recruited neural tissue in the parahippocampal gyrus, whereas evaluating data inconsistent with a plausible theory recruited neural tissue in the anterior cingulate, left dorsolateral prefrontal cortex, and precuneus. We suggest that these findings provide a neural instantiation of the mechanisms by which working hypotheses and evidence are integrated in the brain.