Sterns depicts a very active infant who taking in all aspects of his internal and external environment, formulates the parameters of himself in relation to the world. This formulation is primarily facilitated through the infant-mother dyad. Stern positions vitality affects, amodal perception and attunement as techniques or pathways through which intersubjectivity is experienced and thus internal and external reality identified. Vitality affects appears to be a sort of affective biorhythm or undercurrent that provides a constant stream of continuous affect ranging in intensity, form and rhythm. It is also the bedrock from which discrete emotions such as joy and anger emerge. In order for Stern to support his conceptualization of mother-infant attunement, Stern relies of vitality affects to provide the continuous emotional data required for the mother and child to accurately read each others cues. For without vitality affects, Stern points out that the mother would be in the impossible position of attuning to the sporadic expression of categorical emotion. Amodal perceptions is somewhat like broadband communication – it allows the mother and child to translate each others affect and represent it across a wide spectrum of senses. It allows for a collage of visceral responses and a broader mode of relating.