The article describes that facial expressions in humans and other primates are produced by the coordinated action of muscles that create the various configurations seen during social interactions.[3] For a long time, these expressions were thought to be mainly emotional, reflexive and only minimally controlled by the cerebral cortex, with the cortex mainly associated with voluntary movements such as chewing.[3] Ianni et al. however, they showed that in macaques, the cortical control of facial muscles during social signaling is similar to the control of voluntary actions.[3][4] The results suggest that socially relevant facial movements and voluntary gestures do not use separate pathways, but share coordinated systems of intentional control.[3][4] The study combined functional brain imaging and electrophysiological recordings to track the activity of multiple cortical regions involved in the production of facial gestures.[4] The findings support the notion that facial expressions are the result of a distributed network in the brain that integrates information about internal state, perception, and sensory feedback.[4]