I experienced significant cognitive decline post DBS. I am not positive DBS is the cause but it seems likely. I also experienced a great improvement in my tremor and other symptoms. So good and bad.

I had it on my left side & it really does give you back time!!!

I had bi-lateral DBS-STN surgery in December of 2000. I feel that I gained 10 years. After the surgery, I started DBS4PD.org to provide education to the general Parkinson's population. Please visit the website. I have a variety of reports available that you can download for free. I also invite everyone to take the current survey. It is designed for people with PD who had DBS or did not have it so that we can compare one group to the other to see what's working and what's not.

According to https://bronowski.org/faqs/

"Am I eligible for Deep Brain Stimulation, and if so, what are the positives and negatives to having this surgery?

Deep Brain Stimulation (DBS) is indicated to assist the patient in becoming responsive to dopamine replacement after they have lost this response with prolonged treatment, or have developed severe side effects.

DBS is not approved for treating the primary motor and non-motor symptoms of the disease and does not have any impact on disease progression and it is by no means curative or neuroprotective. It does not provide any improvement over the best effect of Levodopa, as the best response that a patient achieved prior to the surgery will be the same afterward. Notwithstanding the inherent dangers of intracranial surgery, the side effects of DBS include the possibility of developing impaired speech, deterioration of balance and an increase in depression. It is interesting to note that the electrodes used in DBS are implanted into the brain site called the sub-thalamic nucleus (STN) which is connected to the retina by the accessory optic tract. We hypothesize that light therapy could well be changing deep brain function by this connection between the retina and the STN, but is much less invasive. Our current work continues to explore this theme. "

My neurologist said only as last resort and seeing the meds are working for me I'm staying clear of it. There's a lot of research in the field right now so who knows in a few years what they will come up with that's less intrusive than sugery