Alain Ptito, PhD
Professor
Alain Ptito's research investigates the mechanisms involved in cerebral reorganization and plasticity in patient populations (hemispherectomy, callosotomy, Parkinson’s Disease, stroke and TBI). For the past several years, he has been using functional magnetic resonance imaging (fMRI) to investigate motor recovery in stroke and the neural substrates of residual vision in the blind visual field following hemispherectomy. He has also demonstrated that this technique, along with Diffusion Tensor Imaging and evoked potentials, can be used to explore the neural mechanisms underlying traumatic brain injury, particularly in athletes.
In recent years, Ptito has explored new methods of using fMRI for examining brain trauma. In athletes, he has been using fMRI to investigate the neural mechanisms underlying working memory. He has been able to carry out baseline fMRI and neuropsychological testing with hockey and football varsity athletes and to repeat the tests immediately after concussion and subsequently until symptom resolution. His results show that fMRI is sensitive enough to detect abnormal activation patterns in symptomatic concussed individuals and that it could provide an objective way to measure the severity of or recovery from a concussion. More recently, he has been investigating mild TBI in motor vehicle accident victims and in children. He and his team are also investigating treatments, including transcranial magnetic stimulation (TMS). This involves targeting injured regions of the brain with a magnetic field in order to increase blood flow. This is important because blood carries oxygen, a necessary ingredient for a functioning brain. Pilot tests with an MRI system are encouraging as they show TMS does increase blood flow and patients report improvement. In a separate neurostimulation study, sponsored by the U.S. Army and aiming to stimulate neuroplasticity, cerebral reorganization and recovery following mild TBI, Dr. Ptito is investigating whether electrically stimulating the tongue, combined with intensive physiotherapy, is an effective treatment for relieving gait and balance deficits following mild to moderate traumatic brain injury. The tongue is connected to two cranial nerves (V and VII), which are in turn linked to the brain stem. He hopes to show that stimulating the tongue via electrodes stimulates the entire brain and encourages uninjured regions to take over for injured ones.
Neuropsychology, Cognitive Neuroscience
Gagnon, I. and Ptito, A. (Editors). Sports Concussions: A complete guide to Recovery and management. CRC Press, 2018.
Traumatic brain injury: integrated approaches to improve prevention, clinical care, and research. Maas AIR, Menon DK, Adelson PD, Andelic N, Bell MJ, Belli A, Bragge P, Brazinova A, Büki A, Chesnut RM, Citerio G, Coburn M, Cooper DJ, Crowder AT, Czeiter E, Czosnyka M, Diaz-Arrastia R, Dreier JP, Duhaime AC, Ercole A, van Essen TA, Feigin VL, Gao G, Giacino J, Gonzalez-Lara LE, Gruen RL, Gupta D, Hartings JA, Hill S, Jiang JY, Ketharanathan N, Kompanje EJO, Lanyon L, Laureys S, Lecky F, Levin H, Lingsma HF, Maegele M, Majdan M, Manley G, Marsteller J, Mascia L, McFadyen C, Mondello S, Newcombe V, Palotie A, Parizel PM, Peul W, Piercy J, Polinder S, Puybasset L, Rasmussen TE, Rossaint R, Smielewski P, Söderberg J, Stanworth SJ, Stein MB, von Steinbüchel N, Stewart W, Steyerberg EW, Stocchetti N, Synnot A, Te Ao B, Tenovuo O, Theadom A, Tibboel D, Videtta W, Wang KKW, Williams WH, Wilson L, Yaffe K; InTBIR Participants and Investigators. Lancet Neurol. 2017 Dec;16(12):987-1048. doi: 10.1016/S1474-4422(17)30371-X. Epub 2017 Nov 6.
Noninvasive tongue stimulation combined with intensive cognitive and physical rehabilitation induces neuroplastic changes in patients with multiple sclerosis: A multimodal neuroimaging study. Leonard G, Lapierre Y, Chen JK, Wardini R, Crane J, Ptito A. Mult Scler J Exp Transl Clin. 2017 Feb 1;3(1):2055217317690561. doi: 10.1177/2055217317690561. eCollection 2017 Jan-Mar.
Role of advanced neuroimaging, fluid biomarkers and genetic testing in the assessment of sport-related concussion: a systematic review. McCrea M, Meier T, Huber D, Ptito A, Bigler E, Debert CT, Manley G, Menon D, Chen JK, Wall R, Schneider KJ, McAllister T. Br J Sports Med. 2017 Jun;51(12):919-929. doi: 10.1136/bjsports-2016-097447. Epub 2017 Apr 28. Review.
Development, implementation and assessment of a concussion education programme for high school student-athletes. Caron JG, Rathwell S, Delaney JS, Johnston KM, Ptito A, Bloom GA. J Sports Sci. 2018 Jan;36(1):48-55. doi: 10.1080/02640414.2017.1280180. Epub 2017 Jan 17.
Microstructural Integrity of Hippocampal Subregions Is Impaired after Mild Traumatic Brain Injury. Leh SE, Schroeder C, Chen JK, Mallar Chakravarty M, Park MT, Cheung B, Huntgeburth SC, Gosselin N, Hock C, Ptito A, Petrides M. J Neurotrauma. 2017 Apr 1;34(7):1402-1411. doi: 10.1089/neu.2016.4591. Epub 2016 Dec 2.
Cortical Thickness Changes and Their Relationship to Dual-Task Performance following Mild Traumatic Brain Injury in Youth. Urban KJ, Riggs L, Wells GD, Keightley M, Chen JK, Ptito A, Fait P, Taha T, Sinopoli KJ. J Neurotrauma. 2017 Feb 15;34(4):816-823. doi: 10.1089/neu.2016.4502. Epub 2016 Oct 13.
The superior colliculus is sensitive to gestalt-like stimulus configuration in hemispherectomy patients. Georgy L, Celeghin A, Marzi CA, Tamietto M, Ptito A. Cortex. 2016 Aug;81:151-61. doi: 10.1016/j.cortex.2016.04.018. Epub 2016 May 1.
The impact of symptomatic mild traumatic brain injury on complex everyday activities and the link with alterations in cerebral functioning: Exploratory case studies. Bottari C, Gosselin N, Chen JK, Ptito A. Neuropsychol Rehabil. 2017 Jul;27(5):871-890. doi: 10.1080/09602011.2015.1110528. Epub 2015 Dec 9.
Persistent Postconcussive Symptoms Are Accompanied by Decreased Functional Brain Oxygenation. Helmich I, Saluja RS, Lausberg H, Kempe M, Furley P, Berger A, Chen JK, Ptito A. J Neuropsychiatry Clin Neurosci. 2015 Fall;27(4):287-98. doi: 10.1176/appi.neuropsych.14100276. Epub 2015 Mar 24.
Navigational memory functional magnetic resonance imaging: a test for concussion in children. Saluja RS, Chen JK, Gagnon IJ, Keightley M, Ptito A. J Neurotrauma. 2015 May 15;32(10):712-22. doi: 10.1089/neu.2014.3470. Epub 2015 Feb 25.
Noninvasive brain stimulation for persistent postconcussion symptoms in mild traumatic brain injury. Koski L, Kolivakis T, Yu C, Chen JK, Delaney S, Ptito A. J Neurotrauma. 2015 Jan 1;32(1):38-44. doi: 10.1089/neu.2014.3449.
Imaging "brain strain" in youth athletes with mild traumatic brain injury during dual-task performance. Sinopoli KJ, Chen JK, Wells G, Fait P, Ptito A, Taha T, Keightley M. J Neurotrauma. 2014 Nov 15;31(22):1843-59. doi: 10.1089/neu.2014.3326. Epub 2014 Sep 11.