**Parkinson's Disease** is a condition that affects movement and can cause issues like **freezing of gait** (trouble starting or continuing walking). This study looks at how people with Parkinson's adapt to walking on a **split-belt treadmill**. This treadmill has two belts that can move at different speeds, helping researchers understand walking patterns. The study checks if people walk better with a device called **Deep Brain Stimulation (DBS)** turned on or off. DBS is a treatment where small electrical signals are sent to the brain to help control movement. Participants will walk on the treadmill with the DBS device on and off while not taking their usual medication.

• Participants need to be between 18 to 80 years old and have had DBS for at least 6 months.
• The study does not require medication adjustments, but does require walking without aids.
• Participants should not have other neurological conditions or past brain surgeries.