Cycling with anabolic steroids: studying how large fluctuations in sex hormones affect brain structure, functional network organization, cognition and emotions

AAS is commonly administered in a temporal pattern called “cycling”, composed of “on-cycle” periods were supraphysiological doses of AAS in administered for 6-18 weeks, followed by drug-free “off-cycle” periods in order to restore the suppressed hypothalamic-pituitary-testicular (HPT) axis. This administration pattern results in large hormonal fluctuations, which are associated with alterations in mood and behavior, likely resembling alterations in brain chemistry and connectivity. However, it has become clear that these effects are idiosyncratic: most users exhibit little or no psychopathology, while a few demonstrate striking mood changes, and even violence in association with AAS. The mechanisms underlying these effects are largely unknown, but the range and severity seems to increase with the burden of use. Around 30% of AAS users develop a dependence syndrome, with sustained use despite the experience of adverse side-effects. In the present study we will examine how hormonal fluctuations related to AAS exposure and withdrawal affect emotional, cognitive and brain processes. We propose to examine 30 non-using weightlifters, and 35 AAS users when they are taking a course of AAS, and a time point when they are “off-cycle” and not using AAS. Proposed methods include neuroimaging techniques providing information about brain structure, cerebral flow and brain functional network organization, neurocognitive tests, hormone analyses and mental health screening. In addition, we will monitor psychiatric symptoms and relevant side-effects every 14 days.  The proposed study will provide insight into the link between AAS induced hormonal fluctuations, mood symptoms and brain function. Potentially the study will enhance our understanding of sex hormonal influence on brain and behavior in general.