The scanner as a stressor: Evidence from subjective and neuroendocrine stress parameters in the time course of a functional magnetic resonance imaging session

Abstract

Subjects participating in magnetic resonance imaging (MRI) examinations regularly report anxiety and stress related reactions. This may result in impaired data quality and premature termination of scans. Moreover, cognitive functions and neural substrates can be altered by stress. While prior studies investigated pre-post scan differences in stress reactions only, the present study provides an in-depth analysis of mood changes and hormonal fluctuations during the time course of a typical fMRI session. Thirty-nine subjects participated in the study. Subjective mood, salivary alpha-amylase (sAA) and cortisol were assessed at six time points during the lab visit. Associations between hormonal data and neural correlates of a visual detection task were observed using a region of interest approach applied to the thalamic region. Mood and hormonal levels changed significantly during the experiment. Subjects were most nervous immediately after entering the scanner. SAA was significantly elevated after MRI preparation. A subgroup of n=5 (12.8%) subjects showed pronounced cortisol responses exceeding 2.5 nmol/l. Preliminary fMRI data revealed an association between sAA levels and left thalamic activity during the first half of the experiment that disappeared during the second half. No significant correlation between cortisol and thalamic activity was observed. Results indicate that an fMRI experiment may elicit subjective and neuroendocrine stress reactions that can influence functional activation patterns.

Blocking the Mineralocorticoid Receptor in Humans Prevents the Stress-Induced Enhancement of Centromedial Amygdala Connectivity with the Dorsal Striatum

“…For negative mood, missing items (six items in five participants) were replaced by the individual mean score. In line with previous work (Muehlhan et al, 2011), participants naive to the MRI scanner environment showed a stress response to the scanning procedure itself as witnessed by higher heart rate and cortisol levels than non-naive participants (both po0.05). Given that our experimental groups had different percentages of naive participants (58% stress/MR-blocked, 50% stress/MR-available, 62% control/MR-blocked, 25% control/MR-available), we included scanner naivety as covariate of no interest in all of our analyses, including fMRI analyses.…”

Classifying minimally disabled multiple sclerosis patients from resting state functional connectivity

“…Note that in our study, this C + subnetwork predominantly concerns mediotemporal and orbito-frontal regions, normally associated with emotional processing (Kensinger and Schacter, 2008), and could therefore possibly reflect latent affective disturbances often associated with MS (Minden and Schiffer, 1990;Compston and Coles, 2008) and/or higher stress levels in patients during an MRI session (Muehlhan et al, 2011). Alternatively, we cannot exclude that the observed increases in connectivity might partly reflect stronger coherence at low frequencies due to an "idling" state of some networks at rest (Richiardi et al, 2011), subsequent to disconnection lesions in patients.…”

Neuroimaging of prayer: Questions of validity.

“…As shown for psychology in general (Gallagher, 2005) and religion in particular (Coakley, 1997), embodiment's influence on mental processes is considerable and not always personally identifiable. Previous work has shown this to be explicitly the case with fMRI contexts (Muehlhan et al, 2011;Ravicz & Melcher, 2001) and the extent of those effects with regard to prayer research are not documented.…”