The effectiveness of one week of escitalopram therapy in modulating the processing of complex and freely processed emotional stimuli corresponding to daily life emotional situations, in patients with depression is not known.

Inter-subject correlation (ISC) comes as a reliable method to track brain activity during complex, dynamic stimuli in a model-free manner.

A study enrolled 29 individuals suffering from a major depressive disorder to receive 1-week treatment with either escitalopram or placebo, followed by conducting functional MRI (fMRI).

The participants were instructed to listen to verbal-emotional narratives while performing fMRI and the status of ISC was corresponded between the groups, across all the narratives and separately for the episodes with positive and negative valence.

Patients on escitalopram exhibited greater ISC in the default mode network of the brain and the frontotemporal narrative processing areas, while they showed lesser ISC in the middle temporal cortex, hippocampus and occipital cortex, across all the narratives.

Escitalopram was also shown to boost ISC during positive elements of the narratives in the precuneus, medial prefrontal cortex, anterior cingulate and fronto-insular cortex, while no significant synchronization in brain responses was observed to positive vs negative events in the placebo group.

This boost in ISC with Escitalopram displays improved emotional synchronization with others, specifically during observation of positive events.