This research uncovers an almost instantaneous calming response in the heart rates of young mammals and babies when comforted by another. Adults on the other hand cannot calm so quickly. This calming response is an intricate interplay between the nervous, MOTOR (emphasis added) and cardiac systems. My theory is that this calming response manifested by heart rate, evolves in the adult mind into an association with shoulder tension. So while in the adult mammal the heart rate might not quickly slow down when recovering from stress, nevertheless a relaxation of shoulder tension is instantly available in the adult (shrug of the shoulders, upper body sigh, upper body flexibility). A relaxed forequarters keys back in the physical memory to the calmed heart rate. The degree of shoulder tension held in others is what dogs are able to see at a distance when assessing the emotional state of other animals as well as people. The forequarters is the epicenter for generating resistance. Soft shoulders indicate the ease within an individual of being able to flip (ease of deflection) or flop (already feeling grounded) polarities which indicates whether the other being is able to absorb the emotional momentum of others during an interaction. In this way it's possible to be in an adaptable frame of mind even though the heart is racing with excitement (think race car driver). Since all interactions formulate through the motor systems and represent a transfer of emotional momentum, soft shoulders indicate social amenability.