Report from the Baby Lab research team at Paris Descartes University. This unit studies early speech perception and syntactic learning ability in newborns. Researchers use the NIRS (Near-InfraRed Spectroscopy) technique to measure brain activity. NIRS measures the concentration of oxygenated hemoglobin in the blood, which is closely correlated with the activation of neurons that consume oxygen. The NIRS is performed here in a maternity ward, on newborns aged 2 or 3 days.