Manipulating facial musculature with functional electrical stimulation as an intervention for major depressive disorder: a focused search of literature for a proposal.

"Declarations Conflicts of interestIlya Demchenko, Naaz Desai, Stephanie N. Iwasa, Fatemeh Gholamali Nezhad, and Nicholas O. Rule declare no conflict of interest. José Zariffa is the patent inventor for functional electrical stimulation to modulate affect (US-9259576-B2; approved on February 16, 2016); the patent belongs to University Health Network; he has received research support from the Natural Sciences and Engineering Research Council of Canada, Craig H. Neilsen Foundation, Heart and Stroke Foundation of Canada, Wings for Life Spinal Cord Research Foundation, Ontario Ministry of Colleges and Universities, and Praxis Spinal Cord Institute. Sidney H. Kennedy has received honoraria or research funds from Abbott, Alkermes, Allergan, Boehringer Ingelheim, Brain Canada, Canadian Institutes of Health Research, Janssen, Lundbeck, Lundbeck Institute, Merck, Ontario Brain Institute, Ontario Research Fund, Otsuka, Pfizer, Servier, Sunovion, Sun Pharmaceuticals, Xian-Janssen, and holds stock in Field Trip Health. Jeffrey F. Cohn reports grants or contracts from National Institutes of Health and National Science Foundation, and royalties/licenses from the University of Pittsburgh. He receives consulting fees from RealEyes, Xtrodes, Skylyte, has a patent approved on image normalization for facial analysis (US11244206), holds a leadership or fiduciary role at IEEE International Conference on Automatic Face and Gesture Recognition and Association for Affective Computing Society, and holds stock in Deliberate AI and Embodied. Milos R. Popovic is the inventor of the patent for facial electrical stimulation to modulate affect belonging to University Health Network, is the Chief Technology Officer and the Director of Myndtec, Inc., a company that manufactures transcutaneous functional electrical stimulators. He is the Director of KITE, Toronto Rehabilitation Institute – University Health Network (Toronto, ON, Canada) and reports grants or contracts from Connaught Innovation Award, Brain Canada, Mitacs, Webster Foundation, Dean Strategic Funding at the University of Toronto, Natural Sciences and Engineering Research Council of Canada, and Canadian Fund for Innovation. He has a patent approved on February 16, 2016 (USA US-9259576-B2) with Dr. S. Hitzig and Dr. J. Zariffa “Functional electrical stimulation method, use and apparatus for mood alteration”; the patent belongs to University Health Network. He is consulting for a company Fourier Intelligence, which designs rehabilitation robotics technologies, and holds stock in MyndTec. Benoit H. Mulsant holds and receives support from the Labatt Family Chair in Biology of Depression in Late-Life Adults at the University of Toronto. He currently receives or has received for the past three years research support from Brain Canada, Canadian Institutes of Health Research, Center for Addiction and Mental Health Foundation, Patient-Centered Outcomes Research Institute, National Institute of Health, Capital Solution Design LLC (software used in a study funded by Center for Addiction and Mental Health Foundation), and HAPPYneuron (software used in a study funded by Brain Canada). He has also been an unpaid consultant to Myriad Neuroscience for the past three years. Venkat Bhat is supported by an Academic Scholar Award from the Department of Psychiatry at the University of Toronto; he has received research support from the Canadian Institutes of Health Research, Brain & Behavior Foundation, Ministry of Health/Ontario Medical Association Innovation Funds, New Frontiers in Research Fund, Department of National Defense (Government of Canada), and an investigator-initiated trial from Roche Canada. Ethics approval and consent to participateNot applicable to this review article as no original human data are reported. Consent for publicationNot applicable to this review article as no original human data are reported. Conflicts of interest Ilya Demchenko, Naaz Desai, Stephanie N. Iwasa, Fatemeh Gholamali Nezhad, and Nicholas O. Rule declare no conflict of interest. José Zariffa is the patent inventor for functional electrical stimulation to modulate affect (US-9259576-B2; approved on February 16, 2016); the patent belongs to University Health Network; he has received research support from the Natural Sciences and Engineering Research Council of Canada, Craig H. Neilsen Foundation, Heart and Stroke Foundation of Canada, Wings for Life Spinal Cord Research Foundation, Ontario Ministry of Colleges and Universities, and Praxis Spinal Cord Institute. Sidney H. Kennedy has received honoraria or research funds from Abbott, Alkermes, Allergan, Boehringer Ingelheim, Brain Canada, Canadian Institutes of Health Research, Janssen, Lundbeck, Lundbeck Institute, Merck, Ontario Brain Institute, Ontario Research Fund, Otsuka, Pfizer, Servier, Sunovion, Sun Pharmaceuticals, Xian-Janssen, and holds stock in Field Trip Health. Jeffrey F. Cohn reports grants or contracts from National Institutes of Health and National Science Foundation, and royalties/licenses from the University of Pittsburgh. He receives consulting fees from RealEyes, Xtrodes, Skylyte, has a patent approved on image normalization for facial analysis (US11244206), holds a leadership or fiduciary role at IEEE International Conference on Automatic Face and Gesture Recognition and Association for Affective Computing Society, and holds stock in Deliberate AI and Embodied. Milos R. Popovic is the inventor of the patent for facial electrical stimulation to modulate affect belonging to University Health Network, is the Chief Technology Officer and the Director of Myndtec, Inc., a company that manufactures transcutaneous functional electrical stimulators. He is the Director of KITE, Toronto Rehabilitation Institute – University Health Network (Toronto, ON, Canada) and reports grants or contracts from Connaught Innovation Award, Brain Canada, Mitacs, Webster Foundation, Dean Strategic Funding at the University of Toronto, Natural Sciences and Engineering Research Council of Canada, and Canadian Fund for Innovation. He has a patent approved on February 16, 2016 (USA US-9259576-B2) with Dr. S. Hitzig and Dr. J. Zariffa “Functional electrical stimulation method, use and apparatus for mood alteration”; the patent belongs to University Health Network. He is consulting for a company Fourier Intelligence, which designs rehabilitation robotics technologies, and holds stock in MyndTec. Benoit H. Mulsant holds and receives support from the Labatt Family Chair in Biology of Depression in Late-Life Adults at the University of Toronto. He currently receives or has received for the past three years research support from Brain Canada, Canadian Institutes of Health Research, Center for Addiction and Mental Health Foundation, Patient-Centered Outcomes Research Institute, National Institute of Health, Capital Solution Design LLC (software used in a study funded by Center for Addiction and Mental Health Foundation), and HAPPYneuron (software used in a study funded by Brain Canada). He has also been an unpaid consultant to Myriad Neuroscience for the past three years. Venkat Bhat is supported by an Academic Scholar Award from the Department of Psychiatry at the University of Toronto; he has received research support from the Canadian Institutes of Health Research, Brain & Behavior Foundation, Ministry of Health/Ontario Medical Association Innovation Funds, New Frontiers in Research Fund, Department of National Defense (Government of Canada), and an investigator-initiated trial from Roche Canada."

"Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors."