A new study led by Asif Ghazanfar’s lab of Princeton University investigates the evolution of primate facial movements. They found that monkeys coordinate their facial muscles in different ways when communicating than when eating, and these distinct motor patterns implicate different neural mechanisms in the brainstem. These findings give insights into the evolutionary origins of human facial expressions.
Read the abstract: Facial Muscle Coordination in Monkeys during Rhythmic Facial Expressions and Ingestive Movements. Shepherd SA, Lanzilotto M, Ghazanfar AA. Journal of Neuroscience, 2 May 2012, 32(18): 6105-6116; doi: 10.1523/JNEUROSCI.6136-11.2012