Cortisol responses to serial MRI scans in healthy adults and in depression Sabine Peters a,b , Anthony J. Cleare a , Andrew Papadopoulos a , Cynthia H.Y. Fu a, * a Institute of Psychiatry, King’s College London, De Crespigny Park, London SE5 8AF, United Kingdom b Faculty of Social and Behavioral Sciences, Universiteit van Amsterdam, Roetersstraat 15, 1018 WB Amsterdam, The Netherlands Received 27 May 2010; received in revised form 24 September 2010; accepted 12 October 2010 1. Introduction The experience of being in a magnetic resonance imaging scanner has been described as akin to ‘‘being in another world’’ (To¨rnqvist et al., 2006). Up to 30% of subjects undergoing a MRI scan report moderate to severe anxiety, which leads to 5—10% of subjects being unable to complete the scan (McIsaac et al., 1998; Melendez and McCrank, 1993). The hypothalamic—pituitary—adrenal (HPA) axis modulates neurohormonal responses to maintain a home- ostasis in response to stressors (Herman and Cullinan, 1997). It is well established that stressful or novel experi- ences activate the HPA axis resulting in enhanced cortisol secretion. Cortisol levels in turn have been correlated with regional brain activity, for example in the amygdala (van Stegeren et al., 2007), hippocampus (Pruessner et al., 2005) and prefrontal cortex (Wang et al., 2005; Kern et al., 2008). It may be possible that such regional brain activity is confounded by neurohormonal responses to the stressful experience of MRI scanning. Psychoneuroendocrinology (2011) 36, 737—741 KEY WORDS Salivary cortisol; MRI; Stress; HPA axis Summary Magnetic resonance imaging (MRI) scans are a novel environment for most partici- pants. The hypothalamic—pituitary—adrenal (HPA) axis modulates neurohormonal responses to novel and stressful experiences. We sought to examine the neurohormonal responses to MRI scans with the measurement of salivary cortisol. We examined: (1) acute effects of MRI scans by acquiring cortisol measurements immediately preceding and following the scan in comparison with basal cortisol levels, and (2) effects of novelty by measuring cortisol during repeated MRI scans in the same subjects. We examined these effects in two groups of subjects: healthy individuals (n = 27, mean age 41.6 years) and patients with depression (n = 24, mean age 40.0 years). Both groups showed elevated cortisol levels immediately preceding the MRI scan, particularly for the initial MRI scan, which normalised after the follow up MRI scans as compared with mean basal cortisol levels. There were no significant differences in the acute or mean basal cortisol levels between the groups. In summary, the MRI experience is stressful, particularly for the initial scan, but the stress response is reduced with subsequent scans. # 2010 Elsevier Ltd. All rights reserved. * Corresponding author at: Institute of Psychiatry, De Crespigny Park, P074, London SE5 8AF, United Kingdom. Tel.: +44 0207 848 5350; fax: +44 0207 848 0783. E-mail address: cynthia.fu@kcl.ac.uk (C.H.Y. Fu). available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/psyneuen 0306-4530/$ — see front matter # 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.psyneuen.2010.10.009