People utilize multiple expressive modalities for communicating narrative ideas about past events. The three major ones are speech, pantomime, and drawing. The current study used functional magnetic resonance imaging to identify common brain areas that mediate narrative communication across these three sensorimotor mechanisms. In the scanner, participants were presented with short narrative prompts akin to newspaper headlines (e.g., “Surgeon finds scissors inside of patient”). The task was to generate a representation of the event, either by describing it verbally through speech, by pantomiming it gesturally, or by drawing it on a tablet. In a control condition designed to remove sensorimotor activations, participants described the spatial properties of individual objects (e.g., “binoculars”). Each of the three modality-specific subtractions produced similar results, with activations in key components of the mentalizing network, including the TPJ, posterior STS, and posterior cingulate cortex. Conjunction analysis revealed that these areas constitute a cross-modal “narrative hub” that transcends the three modalities of communication. The involvement of these areas in narrative production suggests that people adopt an intrinsically mentalistic and character-oriented perspective when engaging in storytelling, whether using speech, pantomime, or drawing.

Vocal imitation is a phenotype that is unique to humans among all primate species, and so an understanding of its neural basis is critical in explaining the emergence of both speech and song in human evolution. Two principal neural models of vocal imitation have emerged from a consideration of nonhuman animals. One hypothesis suggests that putative mirror neurons in the inferior frontal gyrus pars opercularis of Broca's area may be important for imitation. An alternative hypothesis derived from the study of songbirds suggests that the corticostriate motor pathway performs sensorimotor processes that are specific to vocal imitation. Using fMRI with a sparse event-related sampling design, we investigated the neural basis of vocal imitation in humans by comparing imitative vocal production of pitch sequences with both nonimitative vocal production and pitch discrimination. The strongest difference between these tasks was found in the putamen bilaterally, providing a striking parallel to the role of the analogous region in songbirds. Other areas preferentially activated during imitation included the orofacial motor cortex, Rolandic operculum, and SMA, which together outline the corticostriate motor loop. No differences were seen in the inferior frontal gyrus. The corticostriate system thus appears to be the central pathway for vocal imitation in humans, as predicted from an analogy with songbirds.