Conditioning cortisol

Background:

Preliminary evidence suggests that it might be possible to condition endogenous cortisol, with subsequent psychophysiological effects. In a pilot study with ten participants, promising indications were found for conditioned effects on endogenous cortisol levels and other psychophysiological outcomes. When more systematic research in a larger sample would support these findings, the ability to condition cortisol could offer new therapeutic possibilities.

The aim of this study is to investigate the effects of conditioning with hydrocortisone on endogenous cortisol. Effects of conditioning on endogenous cortisol in response to a short-term psychosocial stress task and other psychophysiological outcomes will also be explored.



Study design:

In line with previous conditioning studies as well as the previous pilot study in ten participants with an analogous design conducted by the research group, a randomized placebo-controlled conditioning paradigm consisting of 2 phases will be applied. In the acquisition phase, consisting of 3 sessions on 3 consecutive days, an unconditioned stimulus (experimental condition: hydrocortisone pill; control condition: placebo pill) is paired with a conditioned stimulus (novel tasting beverage). In the evocation phase, also consisting of 3 sessions on 3 consecutive days a week after the acquisition phase, all participants will be administered a placebo pill paired with the same beverage as in the acquisition phase. Cortisol, alpha-amylase, and self-reported well-being will be measured at several time points during the 6 acquisition and evocation sessions. During each session, participants will also be asked to perform some cognitive tasks and during the last session participants will be exposed to a short-term psychosocial stress task.

Conditioning with hydrocortisone will result in
altered endogenous cortisol during rest in the evocation phase.

During the sessions, cortisol, alpha-amylase and self-reported well-being are measured at several time points

In the experimental group, cortisol is elevated exogenously on three consecutive days by administration of 100 mg hydrocortisone. In the control group, a placebo is administered at the same time points.