Deep Brain Stimulation and its Impact on Speech
- Jud Eson
- Apr 5
- 2 min read
Most are familiar with what Deep Brain Stimulation is, but did you know it could have an impact on your speech? DBS can be applied to two parts of the brain, the globus pallidus internus or the subthalamic nucleus. Both have different impacts on our speech. Let's dive in.

Deep Brain Stimulation (DBS) can have both positive and negative effects on your speech. Positive changes can occur if you are having motor difficulties with speech - impaired tongue movements or movements with your mouth. We can break down the negative effects into two main buckets.
People having a hard time with forming sentences and word findings.
Changes in the volume and clarity of speech.
Subthalamic nucleus (SN) is thought to have a greater positive effect on motor symptoms, but unfortunately has a higher risk of speech impairments. Specifically, word finding and forming sentences (verbal fluency) are worse. People with DBS at the SN are at risk of a 30% reduction in verbal fluency.
Globus pallidus internus (GPI) is thought to have less of an impact on your ability to speak clearly. Some people can still experience dysarthria, or the condition where speech sounds like you have marbles in your mouth, but it does not appear to be as common at the SN.
The higher the voltage settings and the more aggressive stimulation can increase the likelihood of speech disturbances. Additionally, studies that have been conducted examining long term impacts suggest that speech decline can progress over time. This can occur in patients who initially had good outcomes.
How to minimize risk
Build a team of health care providers that you trust. Having confidence in your medical team is so important for outcomes of your care.
Communicate with your team. Make sure any and all concerns/questions are raised. Having a full understanding in your options and possible outcomes will help you make the best decision for you.
Emphasize the experience of your programmer. Your surgeon should be very skilled, but they might not be the same person as who is programming your DBS. Make sure you feel equally confident in both.
See a speech language pathologist prior to surgery. Getting a baseline assessment to track for any changes in the future should not be overlooked. Your therapist can also have you exercises to work on to help reduce the risk of any future speech impairments.
Consider seeing your speech language pathologist yearly or biannually, just like your neurologist. This will allow your speech therapist to screen for any changes and update any exercise programs you are doing to address speech changes.
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