Impairments in spatial memory and spatial navigation are commonly reported amongst patients presenting post-traumatic brain injury (TBI). In this study, the investigators examine the effect of non-invasive deep brain stimulation of the hippocampal-entorhinal complex (HC-EC), a key region supporting navigation abilities, on spatial navigation performance in TBI patients. Using a virtual reality task where participants must first encode and later recall the location of objects in a virtual arena, the investigators contrast performance while active versus control stimulation is applied to the HC-EC. The investigators additionally record brain activity using electroencephalography (EEG) prior to, during, and after task performance to characterize the neural correlates of spatial navigation abilities in TBI patients, and how they are affected by stimulation.
Age ≥ 18 years
Clinical diagnosis of TBI
No history of other severe neurological or psychiatric disorders
Unable to consent
Severe neuropsychiatric (e.g., major depression, severe dementia) or unstable systemic diseases (e.g., severe progressive and unstable cancer, life threatening infectious diseases)
Severe sensory or cognitive impairment or musculoskeletal dysfunctions prohibiting to understand instructions or to perform the experimental tasks
Inability to follow or non-compliance with the procedures of the study
Crossover
Transcranial electric stimulation
Other interventionTranscranial temporal interference stimulation (tTIS) is an innovative non-invasive brain stimulation approach, in which two or more independent stimulation channels deliver high-frequency currents in the kHz range (oscillating at f1 and f1 + Δf). These high-frequency currents are assumed to be too high to effectively modulate neuronal activity. Still, by applying a small shift in frequency, they result in a modulated electric field with the envelope oscillating at the low-frequency Δf (target frequency) where the two currents overlap. The peak of the modulated envelope amplitude can be steered towards specific areas located deep in the brain, by tuning the positions of the electrodes and the current ratio across stimulation channels. Here, the investigators apply tTIS via surface electrodes applying a low-intensity, sub-threshold protocol following the safety guidelines for low-intensity transcranial electric stimulation in humans.
Speed in the spatial navigation task
Participant speed (in seconds) of departure to, and reach of, object location in the virtual reality spatial navigation task.
Accuracy in the spatial navigation task
Accuracy (error, in virtual meters, between correct and recalled object location) in the virtual reality spatial navigation task.
Brain oscillatory activity
Resting-state and task-related EEG recordings are collected, and metrics of oscillatory activity are extracted to characterize the neural activity associated to the primary outcome.
Brain structure and connectivity
Structural, diffusion-weighted, and resting-state MRI scans are performed during the baseline session and are used to evaluate inter-individual anatomical factors associated to the primary outcome.
Age (years)
Participant age will be recorded to examine its influence on individual responsiveness to the intervention.
Montreal Cognitive Assessment questionnaire score
Participant score on the Montreal Cognitive Assessment questionnaire will be collected to examine its influence on individual responsiveness to the intervention.
Frontal Assessment Battery questionnaire score
Participant score in the Frontal Assessment Battery questionnaire will be collected to examine its influence on individual responsiveness to the intervention.
Click on the lead sponsor to view all of their trials.
Friedhelm Hummel
Lead sponsor
Ecole Polytechnique Fédérale de Lausanne
Sponsor institution
Fondation Bertarelli
Collaborator
The Novartis Foundation
Collaborator
Clinique Romande de Readaptation
Collaborator
University of Guadalajara
Collaborator
Swiss National Science Foundation
Collaborator
Wyss Center for Bio and Neuroengineering
Collaborator
Fondation Akiva
Collaborator
Canton du Valais
Collaborator
This trial is not recruiting at the moment. You can still explore other options:
