Monday, February 25, 2013
The Neurotransmitter Dopamine May Be A Key Mediator Of The “Superiority Illusion”
The concept “superiority illusion” refers to the fact that people tend to judge themselves as being superior to the average person when it comes to positive traits such as intelligence, desirability or other personality traits. This is mathematically not possible, because in a normally distributed population, most people cannot be above average. The “superiority illusion” belongs to a family of positive illusions, such as the “optimism bias”, which is characterized by an unrealistic positive outlook regarding our future. It is thought that such positive illusions may help ward off depressive symptoms and promote mental health.
The neural mechanisms responsible for the “superiority illusion” are poorly understood. The recent study “Superiority illusion arises from resting-state brain networks modulated by dopamine” published in the Proceedings of the National Academy of Sciences by Yamada and colleagues used resting functional MRI (fMRI) and PET imaging of the brain in 24 male subjects without known psychiatric or neurologic disease to investigate the neural mechanisms involved in the generation of the superiority illusion. Their findings suggest that the degree of superiority illusion correlates negatively with functional connectivity between two parts of the brain (the anterior cingulate cortex and the striatum) and that the proposed mediator is the neurotransmitter dopamine. This would mean that increasing dopamine levels in the striatum could promote a person’s superiority illusion.
One limitation of the study was that the findings were purely associative and did not prove an actual causal link between dopamine levels and the superiority illusion. Another limitation of the study was that the researchers only performed imaging at one time point and did not track whether changes in the self-perception of superiority in the subjects (over time or in response to certain interventions) also correlated with changes in the brain imaging.
Despite these limitations, the study is quite novel in that it attempts to define the neural mechanism for the “superiority illusion”. The fact that it points to dopamine as a mediator could have important implications. The authors of the paper believe that the “superiority illusion” promotes self-esteem and is an innate counterbalance to depressive symptoms. If further studies confirm a causal role for dopamine in promoting the “superiority illusion”, one could conceivably design novel pharmacologic therapies that target the dopaminergic system and help patients with severe depression who suffer from low-self-esteem.
However, a lot more mechanistic research needs to be conducted before pharmacologic dopaminergic stimulation can be pursued as a treatment for depression. We also need to be aware of the fact that psychiatric medications are often over-prescribed. If newer medications become available which are able to raise self-esteem and foster “superiority illusions”, they might be unnecessarily prescribed to many people who do not suffer from true major depression. The last thing we need is a world in which everyone becomes even more convinced how superior and wonderful they are.
Image credit: Striatum from Anatomography maintained by Life Science Databases(LSDB) via Wikimedia Commons (Creative Commons License).