Acute effects of hydrocortisone on the human brain: An fMRI study

Abstract

Cortisol is essential for regulating all cell types in the body, including those in the brain. Most information concerning cortisol’s cerebral effects comes from work in nonhumans. This is a first effort to use functional magnetic resonance imaging (fMRI) to study the time course and locus of cortisol’s effects on selected brain structures in resting humans. We repeatedly scanned 21 healthy young adults over 45 min to examine changes in the brain’s activity 5 min before, and for 40 min after, an IV injection of 10 mg of hydrocortisone (N = 11) or saline placebo (N = 10). At 15–18 min postinjection we observed in the hydrocortisone group reduced activity in the hippocampus and amygdala that reached a peak response minimum at 25–30 min postinjection (−1 Standard Deviation) relative to placebo. No such effect was seen in the thalamus. Functional MRI appears to be a safe, noninvasive method to study the time course and anatomical effects of glucocorticoids in the human brain.

Stress Modulates the Engagement of Multiple Memory Systems in Classification Learning

“…In line with this view, the activity of the hippocampus was significantly reduced in stressed participants during classification learning. Because previous data suggested that stress or administration of glucocorticoids may reduce the BOLD signal in the hippocampus (Pruessner et al, 2008;Lovallo et al, 2010), it is important to note at this point that stress did not affect hippocampal activity in the visual-motor control task. Thus, stress appeared to reduce specifically PCL-related activity The significance threshold was set at p corr Ͻ 0.05 (FWE-corrected according to SPM8; for ROIs: small volume correction).…”

Cortisol Stress Response in Men and Women Modulated Differentially by the Mu-Opioid Receptor Gene Polymorphism OPRM1 A118G

“…The behavioral relevance of cortisol feedback is illustrated by studies using hydrocortisone to mimic the glucocorticoid feedback limb of a normal stress response. (a) Functional magnetic resonance scans following 10 mg intravenous hydrocortisone injection showed rapid uptake (15 min) in the hippocampus and amygdala, resulting in diminished activation of those structures (Lovallo et al, 2010b). (b) Hydrocortisone (20 mg) acutely suppresses the startle reflex (Buchanan et al, 2001a), thereby modulating behavioral responses to sudden, unexpected stimuli during stress episodes.…”

“…Cortisol increases are a core component of the response to psychological stress, and cortisol in turn serves to regulate the systemic components of the stress response, therefore contributing to long-term homeostasis (De Kloet and Reul, 1987). Cortisol regulation of stress includes negative feedback at the hypothalamus (Dallman et al, 1987) and extrahypothalamic regions of the central nervous system (CNS), including the amygdala, hippocampus, and prefrontal cortex (Lovallo et al, 2010b;McEwen et al, 1968;Sanchez et al, 2000). Cortisol CNS feedback that departs from normal may therefore have implications for long-term regulation of emotions, behavior, and health (Sapolsky et al, 1985).…”

Tune It Down to Live It Up? Rapid, Nongenomic Effects of Cortisol on the Human Brain

“…These gray matter masks were multiplied with the CBF images, which resulted in CBF maps for gray matter to solely analyze gray matter CBF. In Study 1, primary ROIs consisted of regions of the limbic lobe and the subcortical gray matter, because these structures are likely involved in fast cognitive stress effects (Sutanto et al, 1988;Dedovic et al, 2009) and have been reported to show cortisolinduced effects (though not rapid) under low cognitive load (Lovallo et al, 2010). However, since GC binding sites are distributed throughout the entire brain (Sánchez et al, 2000), exploratory ROIs consisted of all regions in the frontal, temporal, parietal, and occipital lobes, and central region.…”

“…Our knowledge about rapid, nongenomic GC action in the CNS is scarce and originates primarily from in vitro studies and animal models (Coirini et al, 1983;De Kloet et al, 1984;Mikics et al, 2004;Ferris and Stolberg, 2010), with a few in vivo studies in humans (Kuehl et al, 2010;Lovallo et al, 2010;Richter et al, 2011). In nonhuman models, GCs were reported to rapidly modulate behaviors that originate in the pons, hypothalamus, midbrain, and limbic system.…”