In the Loop for Walking Well Again

Walking is a central part of independent living. Neurological causes, such as stroke or Parkinson’s disease, can substantially impair gait and mobility. This affects our quality of life, as many studies have shown. In precision rehabilitation, therapy options are continuously adapted to the patient on either a weekly or monthly basis. The new project StimuLoop goes one step further. It adapts the therapy in real time based on data continuously recorded from the individual patient. In addition, therapy effects are boosted by facilitating consolidation processes during sleep. As one of two positively evaluated research consortia of The Loop, it will be funded with five million Swiss francs for the next five years. ZNZ News talked to Andreas Luft, one of the project leaders.

Congratulations on the successful launch of the StimuLoop. The research consortium explores motor rehabilitation in stroke and Parkinson’s patients. What do you intend to „loop“ on the way to recovery?
Andreas Luft: We are closing the LOOP between individual gait patterns in stroke, individual brain activity patterns in Parkinson’s disease, and the patient, i.e. the patient receives real time feedback about gait or activity patterns and can use this feedback to learn to adjust. This adjustment helps to improve functional movement patterns, particularly walking. Because improvement is usually short lived, we aim to enhance its consolidation through personalized sleep-targeted interventions. This consolidation process again closes a loop between brain activity recorded during sleep and real-time adjusted stimulation by odors or sounds.

Using real-time feedback to increase learning during wakefulness sounds plausible. How do you improve the relevant sleep characteristics to optimize its subsequent consolidation? And do stroke and Parkinson’s patients suffer from similar sleep disorders?
The consolidation of learned contents – gait patterns in our case – happens during deep sleep, the so-called delta wave sleep. One can enhance delta sleep with tones synchronized with the sleep waves – a process that we will apply in stroke patients using the novel “SleepLoop” device developed by Christian Baumann and Reto Huber. Alternatively, one can recreate the context, or atmosphere, in which training took place during sleep. Since this has previously been very effectively achieved using odors presented during training and sleep in healthy volunteers, we will follow the same approach in Parkinson’s patients. In stroke we previously found better rehabilitation effects by creating a musical context. The quality of gait patterns will then be tested using advanced ZurichMOVE inertial measurement units to assess whether the sleep and neural training are effective, as well as the longevity of the rehabilitation program.
Stroke and Parkinson patients often do not suffer from similar sleep-wake disorders: in stroke patients, we often observe sleep apnea and hypersomnia, i.e. extended sleep need, whereas Parkinson patients more often suffer from REM sleep behavior disorder, i.e acting out of dreams, and restless legs syndrome.

When looking at the whole project, it seems that there is an incredible variety of methods behind it. How did you manage to bundle all the expertise that is necessary?
We were lucky to build on existing intensive collaborations between our team members in stroke rehabilitation (Andreas Luft), rehabilitation engineering (Roger Gassert), sleep (Reto Huber), Parkinson (Christian Baumann), gait (Bill Taylor) and data analysis (Julia Vogt). These collaborations originated in the Zurich rehabilitation network consisting of ETH, UZH and the associated hospitals, such as USZ, Balgrist and Children’s hospital.

What is the timeline of the project and when do you expect patients to benefit from your insights in their therapeutic settings?
We will start the clinical trials in July 2022. We plan to recruit for 3.5 years and expect to see results in 2026. For the most positive outcomes, the proposed training and consolidation methods will then be translated for clinical use. Apart from the trials, we will gather substantial experience and knowledge with feedback training and sleep, which can be of benefit for patients at even earlier stages of rehabilitation. The meta-analysis of data collected between stroke and Parkinson’s patients will be able to answer important questions related to the origin of symptoms and will hopefully lay the foundations for new therapies in the future.

Click here for further information on The Loop and a video presentation about StimuLoop.