BSc (Physics, University of British Columbia, Canada)

MSc (Kinesiology/Biomechanics, Simon Fraser University, Canada)

PhD (Biomedical Science & Engineering, Aalborg University, Denmark)

Dr Grey is a Senior Lecturer in the School of Sport and Exercise Science. He obtained his PhD in Biomedical Science and Engineering from the School of Sensory-Motor Interaction, Aalborg University, Denmark. Subsequently he has held research appointments at Aalborg University, University of Jyväskylä, Finland and, more recently, at the University of Copenhagen, Denmark where he was cross appointed in the Department of Exercise and Sport Sciences and the Department of Neuroscience and Pharmacology. Dr Grey maintains the position of Guest Researcher at the University of Copenhagen. He has enjoyed research visits in several countries, and maintains active international collaborations with researchers in Australia, Canada, Denmark and the United States.

Dr Grey is developing a new 3rd year Sport and Exercise Science module entitled “Neuroplasticty and Neurorehabilitation”. The module will examine the mechanisms of plasticity from the cellular to system level. It will cover the basic science of neuroplasticity relevant to the normal CNS as it develops and ages; and the how it contributes to the recovery of function following injury to the nervous system. The course will be offered in Autumn 2011.

In the Neuroplasticity and Neurorehabilitation laboratory we study the physiology of human motor system. We use non-invasive techniques, including electrophysiology, transcranial magnetic stimulation and neuroimaging to investigate how the brain and spinal cord change during motor learning and rehabilitation. We are particularly interested in understanding the role played by sensory feedback and using this knowledge to develop better evidence-based rehabilitation strategies.

1. Barthélemy D, Grey MJ, Bouyer L & Nielsen JB. (2011) Involvement of the corticospinal tract in the control of human gait. Progress in Brain Research, In Press.
2. Lorentzen JL, Grey MJ, Crone C, Mazevet D, Biering-Sørensen F & Nielsen JB. (2011) Distinguishing active from pasive components of ankle plantar flexor stiffness in stroke, spinal cord injury and multiple sclerosis. Clinical Neurophysiology, 121, 1939-1951. (link to abstract)
3. Iftime-Nielsen SD, Vingborg RJ, Sinkjær T, Roepstorff A, Christensen MS & Grey MJ. (2011) Cortical and cerebellar activity during grasping exercise augmented with electrical stimulation. Human Brain Mapping, doi: 10.1002/hbm.21191. (link to abstract)
4. Grey, MJ (2010) Proprioceptive Sensory Feedback. In: Encyclopedia of Life Sciences 2010, John Wiley & Sons, Ltd: Chichester http://www.els.net/ doi: 10.1002/9780470015902.a0000071.pub2 (link to abstract)
5. Grey MJ (2010) Locomotion. In: Encyclopedia of Life Sciences 2010, John Wiley & Sons, Ltd: Chichester http://www.els.net/ doi: 10.1002/9780470015902.a0000163.pub2 (link to abstract)
6. Cronin NJ, Klint RA, Grey MJ & Sinkjaer T. (2011) Ultrasonography as a tool to study afferent feedback from the muscle-tendon complex during human walking. Journal of Electromyograpy and Kinesiology, 21, 197-201. (link to abstract)
7. Christensen MS, Lundbye-Jensen J, Grey MJ, Vejlby AD, Belhage B & Nielsen JB. (2010) Illusory sensation of movement induced by repetitive transcranial magnetic stimulation. PLoS ONE 5(10): e13301. doi:10.1371/journal.pone.0013301. (link to abstract)
8. af Klint R, Cronin NJ, Ishikawa M, Sinkjær T & Grey MJ. (2010) Afferent contribution to locomotor muscle activity during unconstrained over-ground human walking: an analysis of triceps surae muscle fascicles. Journal of Neurophysiology, 103, 2747-2756. (link to abstract)
9. Zuur AT, Lundbye-Nielsen J, Leukel C, Taube W, Grey MJ, Gollhofer A, Nielsen JB & Gruber M (2010). Contribution of descending drive to human hopping. Journal of Physiology, 588,799-807. (link to abstract)
10. af Klint R, Mazarro N, Nielsen JB, Sinkjær T & Grey MJ. (2010) Load rather than length sensitive feedback contributes to soleus muscle activity during human treadmill walking. Journal of Neurophysiology, 103, 2747-56. (link to abstract)
11. Grey MJ & Nielsen JB (2009) Integration of spinal reflexes. In: Binder, M.D, Hirokawa, N, Windhorst, U (eds). Encyclopedia of Neuroscience. Springer, Berlin Heidelberg New York.
12. Grey MJ & Nielsen JB (2009) Genoptræning af hjernen: Neuroplasticitet og neurorehabilitering. In: Bøgeskov, J., Ellemann, K., Nielsen, JB. (eds). Hjernen i Bevægelse. København, HjerneForum. pp. 104-113
13. Cronin NJ, Ishikawa M, Grey MJ, Af Klint R, Komi PV, Avela J, Sinkjaer T, Voigt M. (2009) Mechanical and neural stretch responses of the human soleus muscle at different walking speeds. Journal of Physiology, 587, 3375-3382. (link to abstract)
14. Zurr AT, Christensen MS, Sinkjær T, Grey MJ & Nielsen JB. (2009) Tibialis anterior stretch reflex in early stance is suppressed by repetitive TMS. Journal of Physiology, 587, 1669-1676. (link to abstract)
15. af Klint R, Nielsen JB, Sinkjaer T & Grey MJ. (2009) Sudden drop in ground support produces force related unload response in human over-ground walking. Journal of Neurophysiology, 101,1705-12. (link to abstract)
16. af Klint R, Nielsen JB, Cole JD, Sinkjaer T & Grey MJ. (2008) Within-step modulation of leg muscles activity by afferent feedback in human walking. Journal of Physiology, 586, 4643-8. (link to abstract)
17. Barsi GI, Popovic DB, Tarkka IM, Sinkjær T & Grey MJ. (2008) Cortical excitability changes following grasping exercise augmented with electrical stimulation, Experimental Brain Research, 191, 57-66 (link to abstract)
18. Grey MJ, Klinge K, Crone C, Lorentzen J, Biering-Sørensen F, Ravnborg M & Nielsen JB (2008) Post-activation depression of soleus stretch reflexes in healthy subjects and spastic patients. Experimental Brain Research, 185, 189-97. (link to abstract)
19. Mazzaro N, Grey MJ, Nielsen JF & Sinkjær T. (2007) Decreased muscle afferent contribution to the soleus muscle activity during spastic walking. Journal of Stroke and Cerebrovascular Diseases, 16, 135-144. (link to abstract)
20. Grey MJ, Nielsen JB, Mazzaro N & Sinkjær T. (2007) Positive force feedback in human walking. Journal of Physiology, 581, 91-105. (link to abstract)
21. Larsen B, Voigt M & Grey MJ. (2006) Changes in the soleus stretch reflex at different pedaling frequencies and crank loads during pedaling. Motor Control, 10, 265-279. (link to abstract)
22. Mazzaro N, Grey MJ, do Nasciemento O, Sinkjaer T. (2006) Afferent mediated modulation of the soleus muscle activity during the stance phase of human walking. Experimental Brain Research, 173, 713-723. (link to abstract)
23. Mrachacz-Kersting N, Grey MJ & Sinkjær T. (2006) Evidence for a transcortical contribution to the human quadriceps stretch reflex. Experimental Brain Research 168, 529-540. (link to abstract)
24. Ishikawa M, Komi PV, Grey MJ, Lepola V, Bruggemann GP. (2005) Muscle-tendon interaction and elastic energy usage in human walking. Journal of Applied Physiology 99, 603-8. (link to abstract)
25. Mazzaro N, Grey MJ, Andersen JB, Sinkjaer T & Schieppati, M. (2005) Lack of on-going adaptations in the soleus muscle activity during walking patients affected by large-fiber neuropathy. Journal of Neurophysiology 93, 3075-85. (link to abstract)
26. Mazzaro N, Grey MJ & Sinkjær T. (2005) Contribution of afferent feedback to the soleus muscle activity during human locomotion. Journal of Neurophysiology 93, 167-177. (link to abstract)
27. Grey MJ Mazzaro N, Nielsen JB & Sinkjær T. (2004) Ankle extensor proprioceptors contribute to the enhancement of the soleus EMG during the stance phase of human walking. Canadian Journal of Physiology and Pharmacology 82, 610-616. , 610-616 (link to abstract)
28. Grey MJ, Larsen B & Sinkjær T. (2002) A task dependent change in the medium latency component of the soleus stretch reflex. Experimental Brain Research 145, 316-322. (link to abstract)
29. Grey MJ, Van Doornik J & Sinkjær T. (2002) Plantar flexor stretch reflex responses to whole body loading/unloading during human walking. European Journal of Neuroscience 16, 2001-2007. (link to abstract)
30. Grey MJ, Ladouceur M, Andersen JB, Nielsen JB & Sinkjær T. (2001) Group II muscle afferents probably contribute to the medium latency stretch reflex during walking in humans. Journal of Physiology 534, 925-933. (link to abstract)
31. Grey MJ, Pierce CWP, Milner TE & Sinkjær T. (2001) Soleus stretch reflex during cycling. Motor Control 1, 36-49. (link to abstract)
32. Sinkjær T, Nielsen JB, Voigt M, Ladouceur M, Grey MJ & Andersen JB. (2000) Muscle afferent feedback during human walking. In: Cope, T. and Nichols, R. (eds.) Motor neurobiology of the spinal cord. Boca Raton: CRC Press LLC. pp. 215-230