Early Binding of Gaze, Gesture, and Emotion: Neural Time Course and Correlates

Communicative intentions are transmitted by many perceptual cues, including gaze direction, body gesture, and facial expressions. However, little is known about how these visual social cues are integrated over time in the brain and, notably, whether this binding occurs in the emotional or the motor system. By coupling magnetic resonance and electroencephalography imaging in humans, we were able to show that, 200 ms after stimulus onset, the premotor cortex integrated gaze, gesture, and emotion displayed by a congener. At earlier stages, emotional content was processed independently in the amygdala (170 ms), whereas directional cues (gaze direction with pointing gesture) were combined at similar to 190 ms in the parietal and supplementary motor cortices. These results demonstrate that the early binding of visual social signals displayed by an agent engaged the dorsal pathway and the premotor cortex, possibly to facilitate the preparation of an adaptive response to another person's immediate intention.