Characterising mechanisms underlying the brain's response to antidepressant medication Novel insights from neuroimaging

Selective serotonin reuptake inhibitors (SSRIs), selective serotonin and norepinephrine reuptake inhibitors (SNRIs) and (S-)ketamine are currently used as pharmacological treatment for Major Depressive Disorder (MDD). While SSRIs and SNRIs serve as first-line antidepressants, not all patients respond adequately to treatment with these types of medication. (S-)ketamine is currently only used as treatment option for individuals not responding to successive treatment with SSRIs or SNRIs. However, treatment response in MDD varies greatly, and the reasons underlying this variation are not fully understood. One contributing factor may be the limited understanding of how these antidepressants affect brain function. A powerful, non-invasive approach to studying the brain’s functional response to antidepressants is neuroimaging.
In this thesis, we explored the neural correlates and mechanisms underlying the brain's functional response to SSRIs, SNRIs, and (S-)ketamine. To achieve this, we employed a combination of advanced neuroimaging analysis techniques and acquisition methods to investigate changes in brain function and connectivity following treatment with, or administration of, SSRIs, SNRIs, and (S-)ketamine. Additionally, we investigate the potential of structural MRI measures as biomarkers for predicting pharmacological treatment response.