Artículo Eje Hpa Traducido Español

ARTICLE IN PRESS
Psychoneuroendocrinology (]]]]) ], ]]] – ]]]

Available at www.sciencedirect.com

journal homepage: www.elsevier.com/locate/psyneuen

Glucose metabolic changes in the prefrontal cortex
are associated with HPA axis response to a
psychosocial stressor
Simone Kerna, Terrence R. Oakesb, Charles K. Stoned, Emelia M. McAuliffb,
Clemens Kirschbaumc, Richard J. Davidsonb,Ã
aKlinik und Poliklinik fur Neurologie, Technische Universitat Dresden, Germany
¨
¨
The Waisman Laboratory for Brain Imaging and Behavior, University of Wisconsin-Madison, 1500 Highland Avenue,
Madison, WI 53705, USA
c
Institut fur Biologische Psychologie, Technische Universitat Dresden, Germany
¨
¨
d
Department of Cardiology, University of Wisconsin, Madison, USA
b

Received 2July 2007; received in revised form 18 January 2008; accepted 21 January 2008

KEYWORDS
Stress;
HPA axis;
Cortisol;
Prefrontal cortex;
PET;
Controllability;
PET;
MRI;
FDG

Summary
The prefrontal cortex (PFC) has been well known for its role in higher order cognition,
affect regulation and social reasoning. Although the precise underpinnings have not been
sufficiently described,increasing evidence also supports a prefrontal involvement in the
regulation of the hypothalamus–pituitary–adrenal (HPA) axis.
Here we investigate the PFC’s role in HPA axis regulation during a psychosocial stress
exposure in 14 healthy humans. Regional brain metabolism was assessed using positron
emission tomography (PET) and injection of fluoro-18-deoxyglucose (FDG). Depending on
the exactlocation within the PFC, increased glucose metabolic rate was associated with
lower or higher salivary cortisol concentration in response to a psychosocial stress
condition. Metabolic glucose rate in the rostral medial PFC (mPFC) (Brodman area (BA) 9
and BA 10) was negatively associated with stress-induced salivary cortisol increases.
Furthermore, metabolic glucose rate in these regions wasinversely coupled with changes
in glucose metabolic rate in other areas, known to be involved in HPA axis regulation such
as the amygdala/hippocampal region. In contrast, metabolic glucose rate in areas more
lateral to the mPFC was positively associated with saliva cortisol. Subjective ratings on
task stressfulness, task controllability and self-reported dispositional mood states also
showedpositive and negative associations with the glucose metabolic rate in prefrontal
regions.

Abbreviations: ACC, anterior cingulate cortex; IFG, inferior frontal gyrus; maxinc_d, difference in maximum cortisol increase for the stress
and control condition; MFG, medial frontal gyrus; mPFC, medial prefrontal cortex; PFC, prefrontal cortex; SFG, superior frontal gyrus.
ÃCorresponding author.
E-mailaddress: rjdavids@wisc.edu (R.J. Davidson).
0306-4530/$ - see front matter & 2008 Elsevier Ltd. All rights reserved.
doi:10.1016/j.psyneuen.2008.01.010
Please cite this article as: Kern, S., et al., Glucose metabolic changes in the prefrontal cortex are associated with HPA axis response to a
psychosocial stressor. Psychoneuroendocrinology (2008), doi:10.1016/j.psyneuen.2008.01.010

ARTICLEIN PRESS
2

S. Kern et al.
These findings suggest that in humans, the PFC is activated in response to psychosocial
stress and distinct prefrontal metabolic glucose patterns are linked to endocrine stress
measures as well as subjective ratings on task stressfulness, controllability as well as
dispositional mood states.
& 2008 Elsevier Ltd. All rights reserved.

1. Introduction
Thehypothalamus–pituitary–adrenal (HPA) axis is a hierarchically organized stress system, involved in the organism’s adaptation to aversive conditions. Activation of the
HPA axis results in secretion of glucocorticoids, which are
known to have far reaching adaptive effects on the
organism’s metabolism, immune and central nervous system
(Sapolsky et al., 2000). Central stress circuits orchestrate
the...