Neuro-psychiatric disorders encompass a wide range of conditions which affect mental health and cognitive function, including, among others, depression and anxiety disorders. These disorders often involve dysregulation of neural circuitry and neurotransmitter systems in the brain, leading to symptoms such as mood disturbances, cognitive impairments, and altered perception of reality. Non-invasive brain stimulation (NIBS) techniques, such as transcranial direct current stimulation (tDCS), have emerged as promising interventions for neuro-psychiatric disorders. NIBS involves delivering weak electrical currents to specific areas of the brain through electrodes placed on the scalp. By modulating neural activity and connectivity, NIBS aims to restore the aberrant brain function associated with these disorders. Importantly, NIBS offers several advantages, including its non-invasive nature, relatively low cost, and good tolerability. It also provides a unique opportunity for targeted neuromodulation, allowing for precise manipulation of brain networks implicated in the pathophysiology of neuro-psychiatric disorders. As such, NIBS holds great promise as a supplementary treatment strategy, offering new hope for individuals who do not respond adequately to traditional pharmacological or psychotherapeutic interventions. One of the aims of the DiSCoVeR consortium has been to enhance the effectiveness and accessibility of non-invasive brain stimulation (NIBS) for neuro-psychiatric disorders.

NIBS involves delivering weak electrical currents to specific areas of the brain through electrodes placed on the scalp.
CURRENT complete set-up. Illustrated in the image are a neoprene cap, tablet, and tDCS device (Starstim-Home Neuroelectrics), along with QR-like markers used for evaluating cap placement. © Fabienne Windel

In the DiSCoVeR project, the consortium innovatively applies NIBS along with a custom-made tablet-based videogame, which trains cognitive and emotional control. The game delivery is ‘yoked’ to the NIBS application, and further supports improvement of cognitive control functions, such as attentional control, inhition, working memory and cognitive flexibility. These functions rely on the same prefrontal mechanisms targeted by the NIBS, to create synergistic therapeutic effects.

The DiSCoVeR consortium has brought together a multi-national team that includes members from various disciplines to work jointly on this problem. The consortium is coordinated by Mor Nahum from Israel and includes Friedhelm Hummel and Daphne Bavelier from Switzerland, Frank Padberg from Germany, Omer Bonne from Israel, and Elmars Rancans from Latvia.

In a recent paper, published collaboratively by all the consortium partners in the journal Clinical Neurophysiology, Windel et al. introduce a digital tool called CURRENT, an advanced computer-vision tool for stimulation electrode placement at home, designed to improve home-based therapy for psychiatric and neurological disorders. This innovative approach simplifies and enhances the precision of home-based NIBS setups. It introduces, for the first time, an intuitive method to guide patients in the accurate placement of electrodes, thereby enhancing the safety and efficacy of remote NIBS treatments and addresses the challenge of correct electrode placement during home-based NIBS sessions, a crucial yet previously unmet need. By utilizing computer vision and real-time feedback, CURRENT guides patients through the process of electrode placement, ensuring accuracy and quantification of it. This innovation marks a significant departure from conventional onsite approaches, where supervision limits treatment frequency and accessibility. The study demonstrates that participants using CURRENT achieve placement accuracy on par with experts, bolstering their confidence in self-administering therapy. Moreover, positive user feedback underscores the practicality and user-friendliness of CURRENT, making it accessible to a wide range of patients.

According to Fabienne Windel, the lead author of the paper, the implications of the findings are far-reaching. By addressing barriers to accessibility and frequency, CURRENT has the potential to reshape NIBS interventions, making them more inclusive and widely available. This represents a significant step forward in unlocking the full therapeutic potential of NIBS and similar strategies for various rehabilitation and training purposes, including the consortium’s aim to alleviate depression.

Windel further states that while the EPFL laboratory in Switzerland led the development and testing of the CURRENT algorithm, its success was significantly enhanced by the multinational collaboration. Together, the consortium created an integrated system where the CURRENT algorithm is embedded. This system ensures that stimulation and gameplay commence only after successful electrode placement. Developed through the collaborative effort of DiSCoVeR, this system is now being utilized in a multinational randomized clinical trial investigating the potential effects of NIBS and cognitive training in individuals with major depression.

The success of this project was greatly enhanced by the collaborative funding approach that ERA-Net NEURON employs. By bringing together diverse expertise and resources, they played a pivotal role in advancing our research efforts, particularly in developing and implementing the CURRENT tool. This collaborative framework not only accelerated the progress of our project but also ensured its broader impact by fostering international collaboration and promoting the translation of research findings into a large clinical trial.
Fabienne Windel, EPFL, Switzerland

For reference: Windel F, Gardier RMM, Fourchard G, Viñals R, Bavelier D, Padberg FJ, Rancans E, Bonne O, Nahum M, Thiran JP, Morishita T, Hummel FC. Computer vision-based algorithm to sUppoRt coRrect electrode placemeNT (CURRENT) for home-based electric non-invasive brain stimulation. Clin Neurophysiol. 2023 Sep;153:57-67. doi: 10.1016/j.clinph.2023.06.009. Epub 2023 Jul 4. PMID: 37454564.