in numerous studies to giverise to significant improvements in key markers of both physical and psychological health.Significant improvements in several objective health-related measures have been observed,including immune system function (McCraty et al., 1996; Rein et al., 1995), ANS function andbalance (McCraty et al., 1995; Tiller et al., 1996), and the DHEA/cortisol ratio (McCraty et al.,1998). At the emotional level, significant reductions in depression, anxiety, anger, hostility,burnout, and fatigue and increases in caring, contentment, gratitude, peacefulness, and vitalityhave been measured across diverse populations (Arguelles, McCraty, & Rees, 2003; Barrios-Choplin, McCraty, & Cryer, 1997; Luskin et al., 2002; McCraty et al., 1998; McCraty, Atkinson,Lipsenthal, et al. 2003; McCraty, Atkinson, & Tomasino, 2001, 2003). Other research hasdemonstrated significant reductions in key health risk factors (e.g., blood pressure, glucose,cholesterol) (McCraty, Atkinson, Lipsenthal, et al., 2003) and improvements in health status andquality of life in various populations using coherence-building approaches. More specifically,significant blood pressure reductions have been demonstrated in individuals with hypertension(McCraty, Atkinson, & Tomasino); improved functional capacity and reduced depression inpatients with congestive heart failure (Luskin et al.); improved glycemic regulation and qualityof life in patients with diabetes (McCraty, Atkinson, & Lipsenthal, 2000); and improvements inasthma (Lehrer, Smetankin, & Potapova, 2000). Coherence-building interventions have also beenfound to yield favorable outcomes in organizational, educational, and mental health settings(Arguelles et al., 2003; Barrios-Choplin et al.; Barrios-Choplin, McCraty, Sundram, & Atkinson,1999; McCraty et al., 2001; McCraty, Atkinson, Lipsenthal, et al.; McCraty, Atkinson,Tomasino, Goelitz, & Mayrovitz, 1999; McCraty & Childre, 2004; McCraty & Tomasio, 2004).In short, our findings on psychophysiological coherence essentially substantiate what humanbeings have known intuitively for thousands of years: namely, that positive emotions not onlyfeel better subjectively, but they also increase the synchronous and harmonious function of thebodys systems. This optimizes our health, well-being, and vitality, and enables us to functionwith greater overall efficiency and effectiveness.A Typology of Psychophysiological InteractionIn the Appendix A we identify six distinct patterns of HRV, which appear to denote sixdifferent modes of psychophysiological interaction. Four of these modes are readily generated inthe context of everyday life. We have termed these Mental Focus, PsychophysiologicalIncoherence, Relaxation and Psychophysiological Coherence. Two further modes, EmotionalQuiescence and Extreme Negative Emotion, are generated under more extraordinary lifecircumstances. This appendix provides empirical data and detailed descriptions for each of these.INTEGRAL REVIEWDecember 2009Vol. 5, No. 2Looking more closely at our data, we found a number of empirical clues that point to a morefundamental conceptualization of the relationship between HRV patterns (which include bothheart rate and rhythm) and different emotional states. The first clue is that there is a generalrelationship between coherence and emotional valence, in that positive emotions are associatedwith physiological coherence and negative emotions with incoherence. The second clue is that,for certain emotions, we found a relationship between the morphology of the HRV waveformsand specific emotional states. The third finding of significance here is that we also foundevidence of HRV waveform patterns (namely, those characteristic of the Emotional Quiescenceand Extreme Negative Emotion modes) that appear to involve a rapid phase transition into aqualitatively different category of physiological function. In short, the empirical generalizationsuggested by these findings is that the