Selectivity for high-level language processing is highly localized in individual brains

Some aspects of human behavior and cognition depend on focal and selective cortical areas, such as the frontal eye fields or fusiform face area, while others, like semantic knowledge, are broadly distributed across the cortex. Whether higher-level cognitive functions like language can also be highly localized has been a longstanding matter of debate. Here, we provide multiple lines of evidence that receptive language in the brain is subserved by a network of discrete, focal, and uniquely language-selective areas when examining individual brains. Using precision neuroimaging, we observed highly circumscribed patches of cortex that are distinctly selective for language, uniquely consistent in their response properties during language processing, and highly reliable in their anatomical locations within individuals (though variable in location across individuals). These findings indicate that language regions in the brain are characterized by unique functional profiles and sharp boundaries, consistent with the systems neuroscience definition of true "cortical areas."