essence of thetheory of emotion first proposed by William James (1884), which has been refined by manyresearchers over the years.A useful way of understanding how the heart is involved in the processing of emotionalexperience is to draw on Pribrams theory of emotion (Pribram & Melges, 1969). In this theory,the brain is viewed as a complex pattern identification and matching system. Pribrams basicconcept is that of a mismatch between familiar input patterns and current input patterns thatare different or novel. It is this mismatch that provides the mechanism by which feelings andemotions are generated.INTEGRAL REVIEWDecember 2009Vol. 5, No. 2According to Pribrams model, past experience builds within us a set of familiar patterns,which are instantiated in the neural architecture. Inputs to the brain from both the external andinternal environments contribute to the maintenance of these patterns. Within the body, manyprocesses provide constant rhythmic inputs with which the brain becomes familiar. Theseinclude the hearts rhythmic activity; digestive, respiratory and hormonal rhythms; and patternsof muscular tension, particularly facial expressions. These inputs are continuously monitored bythe brain and help organize perception, feelings and behavior.Familiar input patterns form a stable backdrop, or reference pattern, against which newinformation or experiences are compared. When an input pattern is sufficiently different from thefamiliar reference pattern, a mismatch occurs. This mismatch, or departure from the familiarpattern, is what underlies the generation of feelings and emotions. In physiological terms,Pribram suggests that the low-frequency oscillations generated by the heart and bodily systemsare the carriers of emotional information, and that the higher frequency oscillations found in theEEG reflect the integration, perception, and labeling of these body states along with perceptionof sensory input from the external environment. The mismatch between a familiar pattern and apattern that is new or novel in either of these informational inputs is what activates emotionalchanges (McCraty, 2003; McCraty & Tomasio, 2006).Although inputs originating from many different bodily organs and systems are involved inthe processes that ultimately determine emotional experience, it is now abundantly clear that theheart plays a particularly important role. The heart is the primary and most consistent source ofdynamic rhythmic patterns in the body. Furthermore, the afferent networks connecting the heartand cardiovascular system with the brain are far more extensive than the afferent systemsassociated with other major organs (Cameron, 2002). Additionally, the heart is particularlysensitive and responsive to changes in a number of other psychophysiological systems. Forexample, heart rhythm patterns are continually and rapidly modulated by changes in the activityof either branch of the ANS, and the hearts extensive intrinsic network of sensory neurons alsoenables it to detect and respond to variations in hormonal rhythms and patterns (Armour, 1994).In addition to functioning as a sophisticated information processing and encoding center,(Armour & Kember, 2004) the heart is also an endocrine gland that produces and secreteshormones and neurotransmitters (Cantin & Genest, 1985, 1986; Gutkowska, Jankowski,Mukaddam-Daher, & McCann, 2000; Huang et al., 1996; Mukoyama et al., 1991). As we willsee later, with each beat, the heart not only pumps blood, but also continually transmits dynamicpatterns of neurological, hormonal, pressure, and electromagnetic information to the brain andthroughout the body. Therefore, the multiple inputs