Causal evidence from invasive recordings reveals distributed acoustic feature encoding underlying categorical voice perception.

The superior temporal cortex has long been implicated in the perception of vocal sounds, yet most evidence remains correlational. Establishing causal necessity requires demonstrating that disruption of specific neural circuits produces selective perceptual deficits. Here, we report a pediatric patient who underwent intracranial EEG following resection of a left temporal pilocytic astrocytoma that removed anterior and middle superior temporal cortex but spared posteromedial Heschl's gyrus (pmHG) and posterior superior temporal gyrus (pSTG). During an auditory task, broadband high-frequency (BHA) activity revealed voice-selective responses in pSTG, whereas pmHG showed robust auditory responses without category sensitivity. During a two-alternative forced-choice voice-nonvoice discrimination task, direct electrical stimulation of either pmHG or pSTG produced acute, reversible knockouts of categorization, whereas control-site stimulation did not. Cortico-cortical evoked potentials, Granger causality, and diffusion tractography demonstrated preserved bidirectional connectivity between pmHG and pSTG, indicating an intact posterior auditory circuit despite extensive anterior temporal loss. Together, these findings provide causal evidence that categorical voice perception depends on coordinated activity across posterior primary and nonprimary posterior auditory cortex.