Effect of GHB and GHB-induced comas on the brain

Gamma-Hydroxybutyric acid (GHB) is a recreational drug of abuse associated with increasing numbers of GHB-dependent patients and emergency attendances that are often related to GHB-induced coma. However, the effects of chronic GHB-use and/or GHB-induced comas on the brain remain unknown. This thesis aimed to outline the alterations in cognitive processing, resting-state functional connectivity, and brain structure associated with these effects. For this end, 27 GHB users with≥4 GHB-induced comas, 27 GHB users without a coma, and 27 polydrug users who never used GHB, were recruited. Functional magnetic resonance imaging (fMRI) was used to record differences in brain function while participants were at rest, or while performing neurocognitive tasks. Structural MRI and diffusion-weighted imaging were used to record differences in grey and white matter (WM) volume and WM integrity, respectively. Here, for the first time, the effect of chronic GHB-use and the experience of GHB-induced comas was associated with differences in the processing of associative memory, working memory, emotion discrimination, and microstructural differences in WM integrity lasting beyond the state of acute intoxication. The effect of mere GHB-use was associated with functional differences in emotion identification and resting-state functional connectivity. These findings highlight the need of awareness campaigns that minimize the negative lasting health consequences of chronic GHB-use and multiple GHB-induced comas, and to erase the prevailing and erroneous idea that regular use of GHB is not addictive and no harm is associated with severe intoxication by GHB.