Russek & Schwartz, 1997; Seeman & Syme, 1987). In addition, there isabundant evidence that positive emotions affect the activity of the bodys physiological systemsin profound ways. For instance, studies have shown that positive emotional states speed therecovery of the cardiovascular system from the after-effects of negative emotions (Fredrickson etal., 2000), alter frontal brain asymmetry (Davidson et al., 2003), and increase immunity(Davidson et al.; McCraty, Atkinson, Rein, & Watkins, 1996; Rein, Atkinson, & McCraty,1995). Finally, the use of practical techniques that teach people how to self-induce and sustainpositive emotions and attitudes for longer periods has been shown to produce positive healthoutcomes. These include reduced blood pressure in both hypertensive and normal populations,(McCraty, Atkinson, Lipsenthal, et al., 2003; McCraty, Atkinson, & Tomasino, 2003) improvedfunctional capacity in patients with heart failure (Luskin, Reitz, Newell, Quinn, & Haskell,2002), improved hormonal balance, (McCraty, Barrios-Choplin, Rozman, Atkinson, & Watkins,1998) and lower lipid levels (McCraty, Atkinson, Lipsenthal, et al., 2003).In investigating the physiological foundation of this important work, we have utilized HRVanalysis to show how distinct heart rhythm patterns characterize different emotional states. Inmore specific terms, we found that underlying the experience of different emotional states thereis a distinct physiology directly involved. Thus we have found that sustained positive emotionssuch as appreciation, care, compassion, and love generate a smooth, sine-wave-like pattern in thehearts rhythms. This reflects increased order in higher-level control systems in the brain,increased synchronization between the two branches of the ANS, and a general shift inautonomic balance towards increased parasympathetic activity. As is visually evident (Figure 1)and also demonstrable by quantitative methods, heart rhythms associated with positive emotions,such as appreciation, are clearly more coherentorganized as a stable pattern of repeating sinewavesthan those generated during a negative emotional experience such as frustration. Weobserved that this association between positive emotional experience and this distinctivephysiological pattern was evident in studies conducted in both laboratory and natural settings,and for both spontaneous emotions and intentionally generated feelings (McCraty, Atkinson,Tiller, Rein, & Watkins, 1995; Tiller, McCraty, & Atkinson, 1996).By contrast, our research has shown that negative emotions such as frustration, anger, anxiety,and worry lead to heart rhythm patterns that appear incoherenthighly variable and erratic.Overall, this means that there is less synchronization in the reciprocal action of theparasympathetic and sympathetic branches of the ANS (McCraty et al., 1995; Tiller et al., 1996).This desynchronization in the ANS, if sustained, taxes the nervous system and bodily organs,impeding the efficient synchronization and flow of information throughout thepsychophysiological systems. Furthermore, as studies have also shown that prefrontal cortexactivity is reflected in HRV via modulation of the parasympathetic branch of the ANS (Lane,INTEGRAL REVIEWDecember 2009Vol. 5, No. 2Reiman, Ahern, & Thayer, 2001), this increased disorder in heart rhythm patterns is also likelyindicative of disorder in higher brain systems.Figure 1. Emotions are reflected in heart rhythm patterns. The heart rhythm pattern shown inthe top graph, characterized by its erratic irregular pattern (incoherence), is typical of negativeemotions such as anger or frustration. The bottom graph shows an example of the coherent heartrhythm pattern that is typically observed when an individual is experiencing sustained,modulated positive emotions, in this case appreciation.Psychophysiological CoherenceIn our