title: Relationship between Personality Traits and Endogenous Analgesia: The Role of Harm Avoidance.
abstract: BACKGROUND
  Whether psychological factors such as anxiety and pain catastrophizing levels influence the expression of endogenous analgesia in general and, more specifically, the conditioned pain modulation (CPM) response is still under debate. It may be assumed that other psychological characteristics also play a role in the CPM response. The neurotransmitters serotonin, dopamine, and norepinephrine are involved both in CPM, as well as personality traits such as harm avoidance (HA), novelty seeking (NS), and reward dependence (RD), which can be obtained by the Tridimensional Personality Questionnaire (TPQ). However, the associations between these traits (HA, NS, and RD) with endogenous analgesia revealed by CPM have not yet been explored.
  
  
  METHODS
  Healthy middle-age subjects (n = 28) completed the TPQ, Spielberger's State Anxiety Inventory, and the Pain Catastrophizing Scale and were assessed for CPM paradigms using thermal phasic temporal summation as the "test stimulus" and hand immersion into hot water bath (CPM water) or contact heat (CPM contact) for "conditioning stimulus."
  
  
  RESULTS
  Higher levels of HA were associated with less-efficient CPM responses obtained by both paradigms: CPM water (r = 0.418, P = 0.027) and CPM contact (r = 0.374, P = 0.050). However, NS and RD were not associated with the other measurements. No significant relationship was observed between state anxiety and pain catastrophizing levels and the CPM responses.
  
  
  CONCLUSIONS
  The relationship between the capacity of endogenous analgesia and the tendency to avoid aversive experience can be explained by mutual mechanisms involving similar neurotransmitters or brain areas. These findings illuminate the key role of harm avoidance obtained by the TPQ in determining the characteristics of pain modulation profile.
authors.affiliation: The Laboratory of Clinical Neurophysiology, the Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel.
authors.forename: Hadas
authors.initials: H
authors.lastname: Nahman-Averbuch
authors.affiliation: The Laboratory of Clinical Neurophysiology, the Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel.|Department of Neurology, Rambam Medical Center, Haifa, Israel.
authors.forename: David
authors.initials: D
authors.lastname: Yarnitsky
authors.affiliation: The Laboratory of Clinical Neurophysiology, the Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel.
authors.forename: Elliot
authors.initials: E
authors.lastname: Sprecher
authors.affiliation: The Laboratory of Clinical Neurophysiology, the Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel.|Department of Neurology, Rambam Medical Center, Haifa, Israel.
authors.forename: Yelena
authors.initials: Y
authors.lastname: Granovsky
authors.affiliation: The Laboratory of Clinical Neurophysiology, the Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel.|Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel.
authors.forename: Michal
authors.initials: M
authors.lastname: Granot
mesh_terms: D000698:Analgesia / Q000523:psychology*; D001007:Anxiety / Q000523:psychology; D058443:Catastrophization / Q000523:psychology; D003213:Conditioning, Psychological; D005260:Female; D064368:Healthy Volunteers; D006358:Hot Temperature; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010146:Pain / Q000523:psychology*; D010147:Pain Measurement; D010551:Personality; D010556:Personality Tests; D012727:Sex Characteristics
keywords: Tridimensional Personality Questionnaire; anxiety; conditioned pain modulation; harm avoidance; pain catastrophizing