Neuroethics Network and DBS

By Ethan Morris

This post was written as part of a class assignment from students who took a neuroethics course with Dr. Rommelfanger in Paris of Summer 2016.

Ethan Morris is a rising undergraduate senior at Emory University, majoring in Neuroscience and Behavioral Biology with a minor in History. Ethan is a member of the Dilks Lab at Emory and is a legislator on the Emory University Student Government Association. Ethan is from Denver, Colorado and loves to ski.  

One thought-provoking panel at the Paris Neuroethics Network discussed deep-brain stimulation, or DBS. DBS is a relatively novel treatment in which surgeons implant an electrode deep within the brain. When the electrode is turned on, it produces a current that has been shown to alleviate symptoms of Parkinson’s disease. Various studies have provided compelling evidence that DBS may also be an effective treatment for psychiatric disorders, such as major depression, especially when other treatment options are exhausted.

The conference panelists discussed the ethical concerns about DBS, in particular the idea of the “true self” and whether this is affected by DBS. Studies have shown that after DBS surgery, patients can experience personality changes, which has led to some concern that DBS threatens personal identity. The concept of personal identity is nebulous, but some believe that too stark a contrast in personality between pre- and post-DBS constitutes a violation of identity. As was raised by the panelists, this purported identity change may actually be welcomed by the patient who feels their “true self” has been unlocked; however, families may also feel their loved one is no longer the same person. One of the panelists, Dr. Sabine Müller, a German philosopher, firmly believes that DBS treatment should proceed unencumbered by ethical concerns about loss of self. Müller argued there is an erroneously assumed connection between reports of feeling like a different person and metaphysical classifications of personal identity. Müller contended that ethicists overstate negative personality changes, while overlooking accounts of DBS helping patients rediscover themselves. While she did not state it outright, Müller’s analysis reflects her stance as a consequentialist on this issue– she thinks that DBS does not change identity, and consequently, the beneficial outcomes of DBS should outweigh any metaphysical concerns.

Image courtesy of
Dr. Müller argued that the issue with DBS is not a loss of the true self, but rather how people view changes in personality and personal narratives, more generally. One can also imagine that human identity can be static, while there are others who believe that identities are dynamic. Perhaps patients who experience positive changes view them as part of their natural dynamic narrative, while families who are unnerved by the changes see them as a departure from their expectation of others’ stability. The discussion also reminded me of a class discussion on aging and identity, during which there was a debate over whether it is appropriate to say that a person suffering from dementia is no longer the same person. One interesting concept raised in class was that the behavioral and personality changes that coincide with aging elicit these emotional reactions (i.e. they are not the same anymore) because of the rate of change. It is possible that DBS raises ethical concerns about identity because it so rapidly changes the personality of the patient after one procedure. Perhaps humans do not expect others to remain static, but they expect and can comprehend a gradual (i.e. natural) change over time. Either way, Müller argues that these metaphysical exercises are secondary considerations to the beneficial aspects of DBS, including relieved symptoms and, in some cases, positive personality changes.

Furthermore, Müller argued that different people cannot inhabit the same body in one lifetime. Interestingly, this may mean Müller subscribes to a version of Cartesian dualism, in which the self is dissociated from the brain, which theoretically means you could change the brain without changing the self. However, because the concept of the “true self” is elusive and differentially defined, it may not be possible to prove that the brain contains our true selves. Given that scientists do not fully understand the mechanisms by which DBS works. In a review article, Birdno and Grill (2008) highlighted possible DBS mechanisms, including significant changes in cellular activity. If DBS were found to appreciably change brain chemistry, it would be fair to suggest DBS changes our brains. And if the brain is the source of behavior, personality, and perhaps self-identity, then it may not be so trivial that DBS makes physiological changes to the brain. It could mean that these physiological changes cause a shift from the prior self with one kind of brain chemistry to a new self with a different kind of brain chemistry.

Despite the concerns about DBS and identity, I agree with Müller in taking a consequentialist approach to DBS, with a couple significant caveats. Those suffering from Parkinson’s disease, major depression, and other disorders often experience precipitous declines in quality of life that cannot be addressed with other treatments. DBS is a beneficial strategy to alleviate debilitating symptoms, and should continue to be used. However, patients must understand the implications of DBS, even if it is a reversible procedure. By potentially implicating their brain chemistry, they are at risk for changing their personality, either positively or negatively, and patients should be aware of this risk. While Müller argued that detailed pre- and post-surgery consent forms were overcomplicating the procedure, I believe this minor inconvenience is worth the trouble. Additionally, doctors and surgeons must take into account the societal views on personality change. Müller may think the jump from personality change to personal identity change is unwarranted, but the public may not. It is possible that the general public associates the true self with some measure of personality, whether dynamic or static. If people view others’ identity as static, then DBS may upset this expectation, while if people view others’ identities as dynamic, then DBS may accelerate natural change and still be uncomfortable. Ultimately, the concerns over family and societal expectations should not trump the needs of the patients; if patients assume the inherent risks of DBS with full informed consent, they should have the opportunity to better their lives.


Birdno, M.J., W.M., Grill. 2008. Mechanisms of deep brain stimulation in movement disorders as revealed by changes in stimulus frequency. Neurotherapeutics, 5(1): 14-25.

Schermer, M. 2011. Ethical issues in deep brain stimulation. Frontiers in Integrative Neuroscience, 5: 17.

Sironi, V.A. 2011. Origin and evolution of deep brain stimulation. Frontiers in Integrative Neuroscience, 5: 42.

Wrobel, S. 2015. Flipping the switch: Targeting depression’s neural circuitry, Emory Medicine, Spring. Available at: (accessed July 6, 2016).

Want to cite this post?

Morris, E. (2016). Neuroethics Network and DBS. The Neuroethics Blog. Retrieved on , from

Emory Neuroethics on Facebook

Emory Neuroethics on Twitter

AJOB Neuroscience on Facebook