Fax +41 61 306 12 34 E-Mail karger@karger.ch www.karger.com Original Paper Neuropsychobiology 2007;55:143–150 DOI: 10.1159/000106056 The Psychobiology of Burnout: Are There Two Different Syndromes? Mattie Tops a, b, d Maarten A.S. Boksem e Albertus A. Wijers a Hiske van Duinen c Johan A. Den Boer b Theo F. Meijman a Jakob Korf b a Department of Experimental and Work Psychology, University of Groningen, and Departments of b Psychiatry and c Medical Physiology, University Medical Center Groningen, Groningen, The Netherlands; d NeuroInformatics Center, University of Oregon, Eugene, Oreg., USA; e School of Psychiatry, University of New South Wales and Liverpool Hospital, Liverpool, Australia Introduction We recently proposed that low function of the neuro- modulator dopamine is importantly implicated in feel- ings of acute fatigue and listlessness, as well as in the chronic fatigue of syndromes including the highly simi- lar syndromes of burnout and atypical depression [1]. The mesolimbic dopaminergic system is implicated in deci- sions to exert effort and cognitive control functions, and in the vigorousness of responding [1, 2]. Especially dopa- mine D 2 receptor function has been related to effects con- cerning energy expenditure [3, 4]. Pharmacological stud- ies demonstrated that dopaminergic agents modulate feelings of vigor [5, 6] and D 2 receptor blockade increases subjective fatigue [7]. We recently reported several stud- ies that found indirect support for the hypothesis that acute fatigue is associated with decreases in dopaminer- gically modulated cognitive control [8–11]. The phenomenology of burnout suggests an impor- tant role of decreased dopaminergic functioning also in burnout [1]. Together with emotional exhaustion and de- creased perceived personal accomplishment, one of the defining characteristics of burnout is detachment/deper- sonalization. A recent review presented evidence for a re- lationship between attachment and dopaminergic func- tion [12]. A replicated study found a significant correla- tion between dopamine D 2 receptor density in the putamen and scores on a detachment questionnaire [13, Key Words Burnout  Cortisol  Prolactin  Attachment  Detachment  Oxytocin  Fatigue  Dopamine  Serotonin Abstract Background: Plasma prolactin levels are sensitive to dopa- mine and serotonin function, and fatigue. Low cortisol, do- pamine and/or serotonin may be involved in burnout and detachment. Methods: In this double-blind within-subject study, we treated 9 female burnout subjects and 9 controls with 35 mg cortisol and placebo orally. We measured state affect and plasma prolactin, oxytocin, cortisol and adreno- corticotropic hormone levels, and administered an attach- ment questionnaire. Results: The burnout subjects dis- played an extreme distribution of basal prolactin levels, displaying higher or lower levels compared to the controls. The low prolactin burnouts had profoundly low attachment scores and tended to have low oxytocin levels. The high pro- lactin burnout subjects tended to show cortisol-induced de- creased prolactin and fatigue, and increased vigor. Conclu- sion: Results are consistent with the hypothesis that burnout subjects are either characterized by low serotonergic func- tion or by low dopaminergic function, and that the latter group benefits from cortisol replacement. These prelimi- nary results suggest that differentiating between two syn- dromes may resolve inconsistencies in research on burnout, and be necessary for selecting the right treatment strategy. Copyright © 2007 S. Karger AG, Basel Received: August 11, 2006 Accepted after revision: January 27, 2007 Published online: July 18, 2007 Mattie Tops University of Leiden, Department of Education and Child Studies Wassenaarseweg 52 NL–2333 AK Leiden (The Netherlands) Tel. +31 71 527 4077, Fax +31 71 527 3945, E-Mail mtops@fsw.leidenuniv.nl © 2007 S. Karger AG, Basel 0302–282X/07/0554–0143$23.50/0 Accessible online at: www.karger.com/nps