Custom brain implants could treat depression and other illnesses

At Michael Crichton The terminal man, the protagonist Harold Benson suffers from serious crises during which he becomes violent. In order to treat the seizures, doctors implant electrodes in her brain that can detect an impending seizure and stop it before it starts.

The violence inherent in Crichton’s narrative may have increased the narrative tension of the story, but is not indicative of the types of real-world patients this technology could be of benefit to. In the 50 years since the book’s publication, the idea of ​​designing a “brain stimulator” to manipulate brain activity for the benefit of a patient has sprung from the pages of fiction and become reality.

Research by Katherine Scangos, assistant professor in the Department of Psychiatry at the University of California, San Francisco, and her colleagues have successfully used closed-loop deep brain stimulation for the treatment of depression. Their results were published in the journal Natural medicine.

Unlike traditional treatments such as drugs that attempt to modulate brain activity over a large population, closed loop deep brain stimulation (DBS) is personalized based on the patient’s unique brain activity. The system looks for specific biomarkers correlated with the onset of symptoms and intervenes only when needed, addressing specific incidents as they occur. Open loop pacing, another form of DBS, works through a similar process but without incident monitoring and targeted pacing. Where closed-loop DBS kicks in based on a specific set of parameters, the open-loop stimulates a targeted brain region continuously.

Open-loop DBS has shown promise in the treatment of a number of conditions, including Parkinson’s disease and epilepsy, but MDD benefits from a more nuanced approach.

Where the fictitious Benson suffered from seizures, the study participant experienced major depression. The conditions differed, but the treatment strategy was substantially similar.

First, Scangos and his team identified a biomarker present at the onset of symptoms. This is where the personalization process begins. The specific brain activity preceding depressive episodes can vary among individuals and must be understood before deep brain stimulation can occur.

The patient, a 36-year-old female, had suffered from major depressive disorder since childhood. Previous treatments, including antidepressants and electroconvulsive therapy, have not significantly improved symptoms, making it a good candidate for deep brain stimulation.

The study began by implanting an array of 10 electrodes in various regions of the brain to monitor and record neuronal activity over a 10-day period. During this time, the patient self-reported his symptoms, rating them on a scale.

In order to collect a range of ratings, the patient was asked to perform a number of normal activities such as watching a movie or surfing social media. These assessments were compared to recorded brain data to identify patterns of activity related to symptomatic states.

Once a biomarker was determined, the temporary electrodes were replaced with a sensory and stimulation device that continuously monitors brain activity, looking for the identified biomarker. When and if this marker is detected, the device delivers six seconds of stimulation to the affected brain regions.

The patient initially had a score of 36 on the Montgomery-Asberg Depression Rating Scale (MADRS). After treatment with deep brain stimulation, this score fell to 14. Several months later, the score had fallen further to 10, low enough to be considered a remission of symptoms.

Due to the small sample size – one patient – this work does not necessarily predict that the same biomarkers will present in all, or even most, patients with MDD. Likewise, due to the nature of the study, it was not possible to eliminate clinician or patient bias. Further studies with a larger population and control groups will be necessary to improve the quality of the data. While less invasive treatment options are preferable for the majority of patients, therapies such as closed-loop deep brain stimulation could offer much-needed relief for people for whom more traditional therapies are ineffective.

Time will tell if DBS remains effective in the long term for this patient, but the preliminary results are promising. Our individual experience of the world and our lives in it are so unique, so personal. There is something incredibly appealing about neurological therapies that recognize these distinctive traits and treat them accordingly.

About Michael Bill

Check Also

ClearPoint Neuro Congratulates Partner PTC Therapeutics on Receiving Positive CHMP Opinion for Gene Therapy to Treat AADC Deficiency

ClearPoint Neuro, Inc. First gene therapy directly infused into the brain to be delivered with …

Leave a Reply

Your email address will not be published.