Default mode network deactivation during emotion processing predicts early antidepressant response

Abstract

Several previous functional magnetic resonance imaging (fMRI) studies have demonstrated the predictive value of brain activity during emotion processing for antidepressant response, with a focus on clinical outcome after 6–8 weeks. However, longitudinal studies emphasize the paramount importance of early symptom improvement for the course of disease in major depressive disorder (MDD). We therefore aimed to assess whether neural activity during the emotion discrimination task (EDT) predicts early antidepressant effects, and how these predictive measures relate to more sustained response. Twenty-three MDD patients were investigated once with ultrahigh-field 7T fMRI and the EDT. Following fMRI, patients received Escitalopram in a flexible dose schema and were assessed with the Hamilton Depression Rating Scale (HAMD) before, and after 2 and 4 weeks of treatment. Deactivation of the precuneus and posterior cingulate cortex (PCC) during the EDT predicted change in HAMD scores after 2 weeks of treatment. Baseline EDT activity was not predictive of HAMD change after 4 weeks of treatment. The precuneus and PCC are integral components of the default mode network (DMN). We show that patients who exhibit stronger DMN suppression during emotion processing are more likely to show antidepressant response after 2 weeks. This is, to our knowledge, the first study to show that DMN activity predicts early antidepressant effects. However, DMN deactivation did not predict response at 4 weeks, suggesting that our finding is representative of early, likely treatment-related, yet unspecific symptom improvement. Regardless, early effects may be harnessed for optimization of treatment regimens and patient care.

The pulvinar nucleus and antidepressant treatment: dynamic modeling of antidepressant response and remission with ultra-high field functional MRI

“…Elevated pretreatment anterior cingulate activity is most often reported in resting state or facial emotion tasks [6]. Furthermore, the time points of measurement might impact results, since early response might underlie a different neuronal activity as late response [42,43]. A sigmoid response indicates that individual patients respond with a moderate decline of HAM-D values in the beginning, followed by at a certain period of faster response and an again flatter decline at the end of observations.…”

Subcortical Anatomy of the Default Mode Network: a functional and structural connectivity study

“…The same correspondence between connectivity, neurochemistry and cognition applies to the relation between DMN and emotional modulation (Alcalá-López et al, 2017;Bzdok et al, 2013;Mars et al, 2012;Raichle, 2015;Spies et al, 2017;Zhao et al, 2017). The nucleus accumbens is a central output for the dopaminergic projections and is involved in emotion regulation and affect integration (Floresco, 2015;Laviolette, 2007).…”

Rostral Anterior Cingulate Cortex Morphology Predicts Treatment Response to Internet-Based Cognitive Behavioral Therapy for Depression

“…Moreover, as a key hub within the default mode network (DMN) (29), rACC abnormalities – such as manifested in reduced volume – may contribute to maladaptive forms of self-referential processing (24), which could interfere with successful engagement in depression treatment. Of relevance – although not specifically focused on the rACC – a recent study found that greater deactivation of the DMN while engaging with an emotional task predicted enhanced antidepressant response (65). …”