Eduardo Moraud, restoring mobility in Parkinson’s disease

© EPFL

On 23 September, Campus Biotech welcomed Prof. Eduardo Moraud, holder of the newly created Medtronic Chair in Neuromodulation at EPFL. Affiliated with the Neuro-X Institute and the NeuroRestore translational center, the researcher presented his work on the development of adaptive neuromodulation therapies to restore mobility in patients with Parkinson’s disease.

Gait: the blind spot of current therapies
Parkinson’s disease is the fastest-growing neurological disorder in the world. As it progresses, motor symptoms such as tremor and rigidity are joined by gait and balance disorders that vary greatly between patients: asymmetry, difficulty initiating steps, or freezing of gait — a sudden inability to move forward that feels as though the feet are glued to the ground. These disorders contribute to frequent falls and are today a major cause of loss of independence among people with Parkinson’s disease.

Unlike tremor, walking draws on automaticity, voluntary control, sensory integration and attention all at once, and breaks down differently depending on context: a crowded room or a dual task can be enough to trigger an episode. Yet conventional deep brain stimulation (DBS), which has effectively treated tremor and rigidity for almost 40 years by modulating pathological neural activity in the basal ganglia, delivers a continuous stimulation with fixed parameters — poorly suited to symptoms that change from moment to moment.

Stimulation that adapts to walking, in real time
To address this, Prof. Moraud’s team developed algorithms able to decode, from subthalamic nucleus activity recorded by the implant, whether a patient is sitting, standing, walking or freezing — then automatically adjust stimulation accordingly. Tested in four patients and made robust to fluctuations linked to dopaminergic medication, these decoders adapted stimulation amplitude as soon as the patient starts walking to relieve gait impairments, and returned to standard therapeutic parameters at rest to preserve control of cardinal symptoms. The approach, validated in real-world conditions using sensorized shoes, is now backed by new funding from the Michael J Fox foundation for an expanded trial in a larger cohort, including three months in home settings.

New brain targets for freezing of gait
Freezing of gait remains largely resistant to standard DBS. The team hypothesises that it is not a purely motor symptom, but one involving circuits associated with higher-order aspects of movement control. In an animal model reproducing the disease’s dopaminergic degeneration, researchers identified neural projections whose hypoactivity coincides with freezing episodes; by silencing them in healthy animals, they reproduced this behaviour for the first time. EEG recordings in patients provide converging evidence of altered cortical activity during freezing in humans, opening the way to new stimulation targets dedicated to this until-now elusive symptom.

Beyond the brain: stimulating the spinal cord
Finally, his research draws on Lausanne’s expertise in spinal cord stimulation for paralysis, applied here to recruit, in people with Parkinson’s disease, the sensorimotor circuits involved in the control of gait and balance. The first implanted patient, who was falling six to seven times a day, showed sustained improvements in gait asymmetry, walking distance, balance and, unexpectedly, his freezing of gait, with benefits still present several years after implantation. A clinical trial is now under way in six patients, using closed-loop approaches that adjust stimulation in real time, to evaluate the approach in a larger group of patients and more precisely determine its benefits, limitations and individual response profiles.

Research recognised from the moment he joined EPFL
Optimising existing DBS, identifying new brain targets, stimulating beyond the brain: these three directions share a single ambition — mechanistic, personalised and adaptive neuromodulation, recognised this same year with the 2026 Robert Bing Prize from the Swiss Academy of Medical Sciences, for the first physiology-driven approach to adaptive deep brain stimulation. With his arrival at the Neuro-X Institute and Campus Biotech, this research finds a new home, at the crossroads of engineering, neuroscience and clinical practice.