Opioid receptor blockade and warmth-liking: effects on interpersonal trust and frontal asymmetry.
The emotion 'warmth-liking' (WL) associated with feelings of affection and acceptance is regularly activated in social contexts. WL has been suggested to be more closely related to the consummatory phase of post-goal attainment positive affect than to pre-goal attainment positive affect/approach motivation and to be partly mediated by brain opioids. To validate these assumptions we employed film/imagery to induce either a neutral emotional state or WL in female participants after intake of either placebo or the opioid antagonist naltrexone. Dependent variables were emotion self-report, interpersonal trust (TRUST, i.e. a behavioral indicator of WL) and frontal asymmetry (i.e. an electroencephalogram (EEG) indicator of approach motivation/behavioral activation). We found that participants reported more WL in the placebo/WL group than in the placebo/neutral group and both naltrexone groups. In addition, TRUST increased in the WL group after placebo, but not after naltrexone, and this pattern was reversed in the neutral control groups. Consequently, opioid blockade suppressed or even reversed the effects of the WL induction on the levels of self-report and behavior, respectively. In addition, we observed reduced relative left-frontal asymmetry in the WL (vs neutral) group, consistent with reduced approach motivation. Overall, these results suggest opioidergic influences on WL and TRUST and reduced approach motivation/behavioral activation for the positive emotion WL.
Philipps-Universität Marburg, Department of Psychology, 35037 Marburg, Germany.
Desirée
D
Schweiger
Philipps-Universität Marburg, Department of Psychology, 35037 Marburg, Germany.
Gerhard
G
Stemmler
Philipps-Universität Marburg, Department of Psychology, 35037 Marburg, Germany.
Christin
C
Burgdorf
Philipps-Universität Marburg, Department of Psychology, 35037 Marburg, Germany jan.wacker@uni-hamburg.de.
Jan
J
Wacker
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D004311:Double-Blind Method; D004569:Electroencephalography; D004644:Emotions / Q000187:drug effects*; D005071:Evoked Potentials / Q000187:drug effects; D005260:Female; D005625:Frontal Lobe / Q000187:drug effects* / Q000502:physiology; D007839:Functional Laterality / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008297:Male; D009042:Motivation / Q000187:drug effects; D009271:Naltrexone / Q000494:pharmacology*; D009292:Narcotic Antagonists / Q000494:pharmacology*; D057566:Self Report; D035502:Trust; D055815:Young Adult
D009292:Narcotic Antagonists; D009271:Naltrexone
endogenous opioids; frontal asymmetry; interpersonal trust; positive emotion; psychopharmacology