Gyorgy Adam 
Visceral Perception [PDF ebook] 
Understanding Internal Cognition

Author Gyorgy Adam maintains there is a type of sensory system active within the internal organs that appears to be, in some measure, independent of the traditional senses. Variously termed viscerosensory perception, internal perception, or internal cognition, this system operates largely outside of consciousness. Adam employs the extensive data he has gathered over many years to demonstrate how "hidden" internal signals originating in the alimentary tract, the cardiovascular system, and the kidneys may influence emotional states. Visceral Perception is the only comprehensive treatment of this elusive subject.