Psychological vulnerability and stress: the effects of self-affirmation on sympathetic nervous system responses to naturalistic stressors

Health Psychol. 2009 Sep;28(5):554-62. doi: 10.1037/a0014663.


Objective: Everyday stressors can threaten valued aspects of the self. Self-affirmation theory posits that this threat could be attenuated if individuals affirm alternative self-resources. The present study examined whether self-affirmation would buffer cumulative stress responses to an ongoing academic stressor.

Design: Undergraduate participants provided 15-hr urine samples on the morning of their most stressful examination and baseline samples 14 days prior to the examination. Participants were randomly assigned to the self-affirmation condition where they wrote two essays on important values over the 2-week period prior to exam, or a control condition.

Main outcome measures: Samples were analyzed for urinary catecholamine excretion (epinephrine, norepinephrine), an indicator of sympathetic nervous system activation. Participants also indicated their appraisals of the examination experience.

Results: Participants in the control condition increased in cumulative epinephrine levels from baseline to examination, whereas participants in the self-affirmation condition did not differ from baseline to examination. The buffering effect of self-affirmation was strongest among individuals most concerned about negative college evaluation, those most psychologically vulnerable.

Conclusion: The findings demonstrate that sympathetic nervous system responses to naturalistic stressors can be attenuated by self-affirmation. Discussion centers on psychological pathways by which affirmation can reduce stress and the implications of the findings for health outcomes among chronically stressed participants.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Achievement
  • Adaptation, Psychological / physiology
  • Adolescent
  • Anxiety / psychology
  • Anxiety / therapy
  • Anxiety / urine
  • Arousal / physiology*
  • Epinephrine / urine
  • Female
  • Humans
  • Internal-External Control
  • Male
  • Norepinephrine / urine
  • Self Care / psychology*
  • Self Efficacy*
  • Self-Assessment
  • Stress, Psychological / physiopathology*
  • Stress, Psychological / psychology
  • Students / psychology
  • Sympathetic Nervous System / physiopathology*
  • Writing
  • Young Adult


  • Norepinephrine
  • Epinephrine