A cognitive neuropsychologist, Antonio Damasio, who has long studied the correlation between gratitude and neurology, has explored how two major brain regions are activated when people feel grateful. These two areas are the anterior cingulate cortex and the medial prefrontal cortex, which are said to be activated by the serotonergic system.

Damasio and his colleagues had subjects watch videos showing victims of genocide, who had other people help them along the way as part of their story of survival. Using fMRI during these experiments, the researchers found that as subjects watched the videos and empathized with the stories to some extent, their neural circuits for gratitude were robustly activated.

Additionally, researchers including Andrew Huberman and Kelly McGonigal from Stanford University have found that regular gratitude journaling can alter the functional connectivity of emotional pathways. This works by reducing the activation of anxiety and fear circuits, while increasing the activation of circuits for feelings of well-being and motivation.