Heschl's gyrus, posterior superior temporal gyrus, and mid-ventrolateral prefrontal cortex have different roles in the detection of acoustic changes.

A part of the auditory system automatically detects changes in the acoustic environment. This preattentional process has been studied extensively, yet its cerebral origins have not been determined with sufficient accuracy to allow comparison to established anatomical and functional parcellations. Here we used event-related functional MRI and EEG in a parametric experimental design to determine the cortical areas in individual brains that participate in the detection of acoustic changes. Our results suggest that automatic change processing consists of at least three stages: initial detection in the primary auditory cortex, detailed analysis in the posterior superior temporal gyrus and planum temporale, and judgment of sufficient novelty for the allocation of attentional resources in the mid-ventrolateral prefrontal cortex.