Primates interact with each other primarily through visual and acoustic communication. However, while primate social vision has been extensively studied, little is known about the neuronal basis of acoustic communication in primates. More specifically, we ignore how oxytocin, a neurohormone that regulates social behavior in mammals and a promising therapeutic target for psychiatric disorders, modulates acoustic communication. Based on preliminary evidence, I hypothesize that oxytocin (1) acts in the auditory cortex to increase signal to noise ratio in response to social auditory stimuli, (2) is required for normal communication behavior and (3) is critical to brain-to-brain coordination between two interacting individuals. This Global Fellowship proposal has been designed to unveil how oxytocin influences primates’ acoustic communication at the neuronal and behavioral levels. To do so, I combined state of the art techniques, such as chemogenetic manipulation of oxytocin neurons and wireless electrophysiology, in marmoset monkeys. This highly vocal primate was key to this project and a rapidly growing animal model in neuroscience. I learnt to work with them during my Outgoing phase in San Diego (USA) and transfered this knowledge back to Europe during the incoming phase, by participating in the inception of a marmoset laboratory in Lyon (France). This project greatly enhanced my career opportunities in academia as it gave me a unique theoretical and technical background. It placed me in a good spot to explore innovative research pathways, with a great potential scientific impact. All the outcomes from MarmOT are or will be published strictly following the Open Science objective of H2020. This project can benefit society by enhancing our understanding of primate communication and the role of oxytocin, which is a therapeutic target for many psychiatric disorders including autism.
The conclusion of the action is that using chemogenetics methods to activate or inhibit oxytocin neurons in non human primate is feasible, and that the Area 24 of the cortex encodes both emission and perception of vocalizations as well as contextual information such as whether a call is an answer or an isolated call. On a side project, we also found that oxytocin fibers are similarly distributed in the brain of primates and rodents, allowing us to hope for a high degree of translationability between animal models.
