There are numerous studies linking positive emotions to improved health outcomes (1). Several researchers are speculating that the pathway might be the autonomic nervous system (2) (ANS). The ANS is responsible for managing homeostasis  in the body. It consists of two major parts – the sympathetic nervous system (SNS) which generally increases the activity of organs within the body (eg increases heart rate) and the parasympathetic nervous system (PNS) which has the opposite effects to the SNS (eg slows the heart rate ). A useful analogy is that the SNS acts like the accelerator on your car and the PNS like the brakes. In healthy human beings the two parts of the autonomic nervous system work synergistically. The PNS is the most dynamic part of the ANS and tends to respond more quickly than the SNS (3). For example when confronted with a stressor the PNS decreases in activity which allows the SNS to dominate. This activates the so called stress response (“fright, fight or flight”). When the stressor has passed the PNS increases in activity and calms the body restoring it to its normally balanced state. Consequently the PNS is commonly called the calling or relaxation response.

However for various reasons (eg ageing, lack of sleep, chronic stress and lack of exercise) the activity of the PNS can decrease which results in SNS dominance. This impacts on the bodies ability to function optimally, which can in turn result in physical illness (4).

PNS activity is also predictive of emotional health –in particularly the ability to regulate emotions in a healthy and appropriate manner (5) Lower levels of PNS are associated with depression (6), anxiety (7), aggression (8) defensiveness (9), post traumatic stress disorder (10) and hostility (11). Perhaps when we refer to a “nervous breakdown” we are literally referring to a breakdown (failure of the brakes) in the PNS.

Higher levels of PNS are associated with psychological resilience. For example children with higher levels of PNS were less likely to be effected by marital conflict (12). Similarly a longitudinal study found that British Civil servants with higher levels of the PNS are more resilient to stress (13).

There is also evidence that positive emotions are associated with higher levels of PNS activity. Some of the earliest research by Barbara Fredrickson found that positive emotions resulted in quicker heart rate recovery after people had been exposed to film clips that aroused negative emotions (14). New research from Barbara’s Positive emotion and Psychophysiology (PeP) Lab has found that PNS is related to positivity and social connectedness (15). Not surprisingly asking people to recall an experience where they felt gratitude results in higher levels of PNS (16). Barbara Fredrickson’s And higher levels of PNS are associated with spirituality (17).
There are a number of interventions that increase PNS activity. For example effective stress management techniques such as exercise (18), tai chi (19), meditation (20), massage (21) and yoga (22) – as does consuming fish oil (23). And for some reason walking a dog increases PNS more than walking by yourself (24)

There is also PC based software that teaches you to breathe in an optimal way to increase PNS (25). The software has been effective in treating depression (26), asthma (27), fibromyalgia (28), anger and anxiety (29).

The software also appears to be sensitive to a persons emotional state. I have used the software in my resilience workshops and have made the following empirical observations about factors that increase PNS:

• Engaging in flow activities
• Resolution of a problem
• Practicing mindfulness
• Reflecting on activities that align with values/strengths
• Engaged in an active constructive conversation

The software is my preferred coaching tool as it takes all the guess work out of identifying what activates a persons positive emotions – particularly the most powerful positive emotion called contentment (30). This shouldn’t be surprising given that the software is measuring instantaneous levels of the calming response.

We all talk about living more balanced lives – beyond the metaphor perhaps we are referring to a balanced autonomic nervous system that allows us to respond to (and recover from) life’s inevitable challenges.

References

1. Steptoe, A., Wardle, J. (2005). Positive affect and biological function in everyday life. Neurobiology of Aging, 26, S108-S112.
2. Thayer, J.F., Ruiz-Padial, E. (2006). Neurovisceral integration, emotions and health: An update. International Congress Series, 1287, 122-127.
3. Porges, S.W. (2001). The polyvagal theory: Phylogenetic substrates of a social nervous system. International Journal of Psychophysiology, 42, 123–146.
4. Masi, C.M.,  Hawkley,L.C., Rickett, E.M., Cacioppo, J.C. (2006). Respiratory sinus arrhythmia and diseases of aging: Obesity, diabetes mellitus, and hypertension. Biological Psychology, 74 (2), 212-223.
5. Appelhans, B.M., Luecken, L J. (2006). Heart rate variability as an index of regulated emotional responding. Review of General Psychology, 10(3), 229-240.
6. Chambers A.S.,  Allen, J.B. (2002). Vagal tone as an indicator of treatment response in major depression. Psychophysiology, 39, 861-864.
7. Friedman, B.H., Thayer, J.F. (1998). Anxiety and autonomic flexibility: A cardiovascular approach. Biological Psychology, 49, 303-323
8. Beauchaine, T.P., Gatze-Kopp, L., Mead, H.K. (2007). Polyvagal theory and developmental psychopathology: Emotion dysregulation and conduct problems from preschool to adolescence. Biological Psychology, 74, 174-184.
9. Movius, H.L., Allen, J.N. (2005). Cardiac vagal tone, defensiveness and motivational style. Biological Psychology, 68, 147-162.
10. Hopper, J.W., Spinazzola, J., Simpson, W.B., Van Der Lol., B.A. (2006), Preliminary evidence of parasympathetic influence on basal heart rate in post traumatic stress disorder. Journal of psychosomatic research, 60, 83-90.
11. Virtanen, R., et al. (2003). Anxiety and hostility are associated with reduced baroreflex sensitivity and increased beat-to-beat blood pressure variability. Psychosomatic Medicine, 65(5), 751–756.
12. Katz, L.F. & Gottman, J.M. Buffering children from marital conflict and dissolution (1997). , 26(2), 157-171.
13. Britton, A., Singh-Manoux, A., Hnatkova, K., Malik, M., Marmot, M.G., Shipley, M. (2008). The association between heart rate variability and cognitive impairment in middle-aged men and women: The Whitehall II cohort study. Neuroepidemiology 31 (2), 115-121.
14. Fredrickson, B., Levenson, R. (1998). Positive emotions speed recovery from cardiovascular sequelae of negative emotions. Cognition and Emotion, 12, 191-220.
15. http://www.bethanykok.com/BEK_APS_5_23_08.pdf
16. McCraty, R., Atkinson, M. Willer, W.A. Rein, G. Watkins, A.D. (1995), The effects of emotions on short-term power spectrum analysis of heart rate variability. American Journal of Cardiology, 76 (14), 1089-1092.
17. Berntson, G.G. , Norman, G.J. , Hawkley, L.C. (2008) Spirituality and autonomic cardiac control. Annals of Behavioural Medicine,  35(2), 198-208.
18. Sandercock, G.R., Bromley, P.D., Brodie, D.A. (2005). Effects of exercise on heart rate variability: Inferences from meta analysis. Medical Science Sports Exercise, 37(3), 433-439.
19. Lee, M.S., Huh, H.J., Kim, B.G., Ryu, H., Lee, H.S., Kim, J.M., Chung, H.T. (2002). Effects of Qi-training on heart rate variability. American Journal of Chinese medicine, 30(4), 463-70.
20. Takahashi, T., Murata, T., Hamad, T. Omoria, M. Koska, H, Kikuchi, M, Yoshida, H., Wada, Y. (2005). Changes in EEG and autonomic nervous system activity during meditation and their association with personality traits. International Journal of Psychophysiology, 55, 199-207.
21. Delaney, J.P., Leong, K.S., Brodie, D. (2002). The short term effects of myofascial trigger point massage therapy on cardiac autonomic tone in healthy subjects. Journal of Advanced Nursing, 37(4), 364-71.
22. Khattab, K., Khattab, A.A., Ortak, J., Richardt, G., Bonnemeier, H.(2007). Iyengar Yoga increases cardiac parasympathetic nervous modulation among healthy yoga practitioners. Evidence-based Complementary and Alternative Medicine 4(4), 511-517
23. Holguin, F., Téllez-Rojo, M.M., Lazo, M., Mannino, D., Schwartz, J., Hernández, M., Romieu, I. (2005). Cardiac autonomic changes associated with fish oil vs soy oil supplementation in the elderly. Chest, 127 (4), 1102-1107.
24. Mattok, M., Koike. H., Yokoyama, T., Kennedy, N.L. (2006). Effect of walking a dog on autonomic nervous system activity in senior citizens. Medical Journal of Australia, 184(2), 60-62.
25. Lehrer, P. M., Vaschillo, E., Vaschillo, B., Lu, S.-E., Eckberg, D. L., Edelberg, R., et al. (2003). Heart rate variability biofeedback increases baroreflex gain and peak expiratory flow. Psychosomatic Medicine, 65, 796–805.
26. Karavidas, M. K., Lehrer, P. M., Vaschillo, E., Vaschillo, B., Marin, H., Buyske, S., et al. (2007). Preliminary results of an open-label study of heart rate variability biofeedback for the treatment of major depression. Applied Psychophysiology and Biofeedback, 32, 19–30.
27. Lehrer P.M., Vaschillo E, Vaschillo B, et al. (2004) Biofeedback treatment for asthma. Chest, 126, 352 - 61.
28. Hassett, A. L., Radvanski, D. C., Vaschillo, E. G., Vaschillo, B., Sigal, L. H., Karavidas, M. K., et al. (2007). A pilot study of the efficacy of heart rate variability (HRV) biofeedback in patients with fibromyalgia. Applied Psychophysiology and Biofeedback, 32, 1–10.
29. Reiner, R. (2008). Integrating a Portable Biofeedback Device into Clinical Practice for Patients with Anxiety Disorders: Results of a Pilot Study. Applied Psychophysiology Biofeedback 33, 55–61.
30. Gilbert, P., McEwan, K., Mitra, R., Franks, L., Richter, A., Rockliff, H. (2008). Feeling safe and content: A specific affect regulation system? Relationship to depression, anxiety, stress, and self-criticism.Journal of Positive Psychology,  3(3) 182-191.

Higher levels of testosterone are correlated with financial risk-taking behavior. Click here to read article.

Evolution and Human Behavior, 2008

Political conservatives operate out of a fear of chaos and absence of order while political liberals operate out of a fear of emptiness. Click here to read the article.

Journal of Research into Personality, September 2008 

When you’re upset or depressed, should you analyze your feelings to figure out what’s wrong? Or should you just forget about it and move on? Click here to find out the surprising answer

Personality and Social Psychology Bulletin, July 2008

People who react more strongly to bumps in the night, spiders on a human body or the sight of a shell-shocked victim are more likely to support public policies that emphasize protecting society such as more defense spending, more government resources directed at fighting terrorism and tighter controls on immigration. Click here to read article.

Science, September 2008

A mother’s stress may contribute to her young children being overweight in low income households with sufficient food. Click here to read article.

A series of experiments conducted by researchers at the University of Illinois suggest that society’s emphasis on action over inaction may lead to unforeseen consequences. Click here to read the article.

Personality and Social Psychology, September 2008

Researchers looked at the early career success (salary and performance) based on two year long data from a sample of recent business college graduates.

They found that that gender, extroversion, and agreeableness were the strongest predictors of salary. Emotional stability and proactive personality (e.g., lead and plan more effectively, and adapt more quickly to new situations) predicted perceived job success, while extroversion was significantly related to perceived career success.

Interestingly Emotional Intelligence didn’t predict early career success.

International Journal of Selection and Assessment, 16(3), 292-300.

Experienced Zen meditators can clear their minds of distractions more quickly than novices, according to a new brain imaging study. Click here to read article.

Public Library of Science One (PLoS ONE). http://dx.plos.org/10.1371/journal.pone.0003083

The Fitness for the Ageing Brain Study, conducted over 18 months at the University of Western Australia, is believed to be the first in the world to demonstrate that moderate exercise can positively affect cognitive function.  Click here to read article

Journal of the American Medical Association,  September 2008.