Kumar, J., Vollm, B. & Palaniyappan, L. Oxytocin affects the connectivity of the precuneus and the amygdala: A randomized double-blinded placebo-controlled neuroimaging trial
Maternal milk ejection and bonding are regulated by the hormone oxytocin. In recent times a great deal of interest is seen in using oxytocin as a therapeutic agent to enhance social behavior. Many researchers consider oxytocin (administered through the nose!) as a prosocial agent that enhances an individual's capacity to appreciate human emotions. The brain network-level mechanism for such action is so far unknown.
We studied a sample of 15 healthy males in a randomized cross over trial with oxytocin and placebo. Using resting functional MRI scans, we noted that the time series of haemodynamic fluctuations in a key brain region that engages in emotional processing and conditioning called amygdala, gets dissociated (or uncoupled) from a central hub region called precuneus.
This observation is important as precuneus is often considered to be a part of the default-mode network - a microcircuit that appears to be tonically active (‘busy’) when we are not operating on our environment, but gets suppressed (‘quietened’) when we focus on the ‘present’ and pay attention to the world around us. By disengaging amygdala from precuneus, oxytocin may be facilitating a person’s receptiveness to the social world.
If this mechanism is indeed true and replicated by other groups, this may raise a hope for treating reduced sociality that is a hallmark of several psychiatric disorders, including schizophrenia, depression, autism and certain personality disorders.
Maternal milk ejection and bonding are regulated by the hormone oxytocin. In recent times a great deal of interest is seen in using oxytocin as a therapeutic agent to enhance social behavior. Many researchers consider oxytocin (administered through the nose!) as a prosocial agent that enhances an individual's capacity to appreciate human emotions. The brain network-level mechanism for such action is so far unknown.
We studied a sample of 15 healthy males in a randomized cross over trial with oxytocin and placebo. Using resting functional MRI scans, we noted that the time series of haemodynamic fluctuations in a key brain region that engages in emotional processing and conditioning called amygdala, gets dissociated (or uncoupled) from a central hub region called precuneus.
This observation is important as precuneus is often considered to be a part of the default-mode network - a microcircuit that appears to be tonically active (‘busy’) when we are not operating on our environment, but gets suppressed (‘quietened’) when we focus on the ‘present’ and pay attention to the world around us. By disengaging amygdala from precuneus, oxytocin may be facilitating a person’s receptiveness to the social world.
If this mechanism is indeed true and replicated by other groups, this may raise a hope for treating reduced sociality that is a hallmark of several psychiatric disorders, including schizophrenia, depression, autism and certain personality disorders.
- First study to consider the effect of oxytocin on localised connectivity measure using fMRI.
- First study investigating the centrality (a property of brain hubs) after oxytocin administration.
- Published in The International Journal of Neuropsychopharmacology (IF:5.3)