Novel Neuromodulation

Neurostimulation is an evolving therapy for treatment-resistant depression that involves the application of electromagnetic stimuli (magnetic field or electric current) to the brain. Applied magnetic or electrical stimulus stimulates nerve cell activity and triggers the body’s natural biological response by releasing neurotransmitters – specialized chemicals that allow brain cells to communicate with each other. Brain stimulation modulates the firing pattern of nerve cells and stabilizes the interaction between different parts of the brain. The treatment is non-invasive, meaning that no surgery is required. 

The Interventional Neuropsychiatry Program at St. Michael’s Hospital carries out a number of research studies to explore the clinical efficacy and functional outcomes of the following brain stimulation treatments: 

1) Temporal Interference Stimulation (TI)

2) Repetitive Transcranial Magnetic Stimulation (rTMS)

3) Functional Electrical Stimulation (FES)

The ultimate goal of this research is to develop novel clinical tools for the diagnosis, prognosis, and treatment of treatment resistant depression. The studies explore how certain biological markers in the form of behavioural measures, EEG, or MRI can be used to clinically quantify and predict treatment response to brain stimulation. This research focuses on personalized medicine approaches and aims to determine optimal individual treatment parameters in each patient for the most beneficial outcome. 

Below is a list of our current clinical trials, and the contact information for the study coordinator, who can answer any questions you may have about the study, including the referral and intake process. Research funds are available to cover the full cost of treatment for participants who wish to enroll in these trials.

Ongoing Studies

Temporal Interference (TI) for Depression


Temporal Interference (TI) stimulation is a novel promising form of non-invasive transcranial electrical stimulation that is the first of its kind to stimulate brain regions located deep below the surface. Non-invasive brain stimulation techniques have been around for several decades but their application has been limited to the superficial regions of the brain. Depression, however, is known to also be associated with a brain region called the subgenual anterior cingulate cortex which is located deep below the surface. The potential ability of TI to target this region offers a promising potential in advancing scientific knowledge of brain function and offers an emerging therapeutic application for major depression. 


  • Inclusion Criteria
  1. Any sex or gender, age 18 to 65 years
  2. Diagnosis of Major Depressive Disorder
  3. Able to speak and understand English
  • Exclusion Criteria
  1. History of bipolar disorder or psychosis
  2. Current substance use or history of substance use during the past year (excluding nicotine and caffeine use disorder)
  3. Certain medical illnesses and blood test results 
  4. Recent change in treatment regimen for depression than happened less than 1 month ago

Treatment Protocol:

  • You will receive 10 sessions of TI stimulation or placebo stimulation, for a total of 2 weeks (weekdays only). Each treatment session lasts 30-40 minutes. 
  • On certain days of treatment, we will record electroencephalography – a non-invasive recording procedure that allows to monitor brain activity 
  • You will be undergo two 1-hour sessions of magnetic resonance imaging before and after treatment
  • You will be followed for 1 month after completing treatment 

 “Take-Home” Functional Electrical Stimulation (FES) for Depression


Bilateral functional electrical stimulation (FES) of the facial muscles involves stimulating specific facial muscles with an FES device  and is being investigated as a potential novel intervention for major depressive disorder (MDD). Applying FES on specific facial muscles related to smile patterns may result in better control of emotions and mood elevation. FES is a low-risk, non-invasive technique which causes muscles to contract using electrical current. The purpose of this study is to learn whether FES of the facial muscles is effective in treating MDD and to develop a model (personalized 3D printed mask and programmable stimulator) for take-home delivery.


  • Inclusion Criteria: 
  1. Diagnosis of Major Depressive Disorder
  2. Male or non pregnant female, above 18 years of age
  3. No change in the medication regimen or other forms of treatments for at least 4 weeks prior to beginning the study, during the 20-session treatment period, and the 4-week post-treatment observation period.
  • Exclusion Criteria: 
  1. Have a history of epilepsy or seizures
  2. Have any damage or dysfunction of facial nerves

Treatment description:

 In this study, we will be applying FES to specific facial muscles. This electrical current may cause gradual, long-lasting changes in brain activity levels due to the physiological connection existing between facial muscles and the brain. 

  • In the first study visit  personalized 3D masks will be manufactured and delivered to participants.
  • Participants will be randomized to receive either 20 home-based sessions (45 minutes) of  FES or sham stimulation over 4 weeks.
  • Depressive symptoms will be assessed pre-treatment, after every five treatment days, and during the post-stimulation visits.