We know that the interactions between mums and infants are special and that mums have a unique role to play in helping infants regulate their emotions. Our heart rate projects involve using measures of cardiac output to better understand the physiology underlying mother-infant interactions. In these projects, we record heart rate activity by gently placing small sensors on three points; one at the back of the neck and one next to each collarbone. Previous projects have observed mothers’ heart rate activity as they play with their infant in a safe and calm environment, as well as during a resting state during which mums sit and listen to a meditation audio recording.