Deep brain stimulation (DBS) is the most common surgical treatment for Parkinson’s disease. It uses continuous electrical pulses to help control movement symptoms like tremor, stiffness and slowness.
For many, DBS can be life changing. Its big shortfall is that it delivers the same stimulation all the time, which does not help with walking difficulties — including unsteady gait, freezing of gait and falls. These are among the most disabling and dangerous Parkinson’s symptoms with limited treatment options.
Recently, major advancements have been made in adaptive DBS (aDBS), which is when a DBS device adjusts its stimulation in real time based on a person’s symptoms or behaviour. Studies show that aDBS is more helpful for controlling typical “on/off” symptoms (such as tremor and rigidity) compared to traditional DBS treatment.
Now, two new studies published in Nature Medicine suggest that aDBS may also hold promise for treating gait impairment in people with Parkinson’s.
One study, conducted by a team at Lausanne University Hospital in Switzerland, developed a system that uses brain signals to detect which locomotor (the ability to move) activity a person is performing — such as sitting, standing, walking or turning — and selects stimulation settings optimized for that specific activity.
The other study, led by a team at the University of California, San Francisco (UCSF), took a different approach: timing stimulation to specific phases of the walking cycle, footstep by footstep, guided by brain signals unique to each individual participant.
Both studies were small and early-stage but highlight that adaptive DBS could improve walking in ways that traditional DBS cannot.
Study Results
The primary focus of both studies was whether adaptive DBS settings that target gait are feasible and safe, and whether they could improve walking compared to traditional continuous stimulation. Encouragingly, neither study reported negative events.
Adaptive DBS was well tolerated in all participants, and both studies found that it still helped manage the movement symptoms — like tremors and stiffness — that traditional DBS provides. Beyond safety, both teams also tracked changes in participants’ walking patterns, including step consistency, symmetry and falls.
The Swiss study enrolled six people with Parkinson’s who had DBS implants in the subthalamic nucleus. The team used recordings from the implanted DBS device, combined with detailed motion tracking, to develop algorithms that could detect which activity a person was performing — walking on flat ground, avoiding obstacles, turning, etc. — and automatically adjust stimulation settings to match.
This approach improved movement across multiple daily activities while preserving the benefits of traditional DBS for other movement symptoms.
This system successfully decoded and adjusted to locomotor activities in real time, even as participants’ symptoms changed or took levodopa medication throughout the day — a key challenge for adaptive approaches.
The University of California study enrolled five people with Parkinson’s who received DBS implants in the globus pallidus region, along with additional recording devices in other brain regions. Using those recordings, they found that the brain produces distinct electrical patterns during specific phases of walking — for example, when the leg swings forward.
These patterns were unique to each participant, appearing at different frequencies and brain locations. By identifying each person’s individual ‘gait signature,’ the researchers were able to program the neurostimulator to deliver brief boosts of stimulation timed to match each step.
During in-clinic testing, this adaptive DBS strategy improved step variability and step symmetry compared to traditional DBS stimulation.
Three participants completed a multi-day trial in their own homes, where neither the participants nor the researchers knew which type of stimulation was being used. In this real-world setting, adaptive DBS maintained general movement symptom control and reduced falls.
While these are early results need to be confirmed in larger studies, they offer a promising glimpse into a fundamentally new way to address one of the most challenging aspects of Parkinson’s: walking difficulties.
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