Research Group

Petro Julkunen

Professor, University of Eastern Finland

Assistant chief physicist, Kuopio University Hospital

Neuromuscular biomechanics and imaging

Personal information

  • Phone: +358 50 348 3300
  • Address 1: Department of Applied Physics, University of Eastern Finland, POB 1627, 70210, Kuopio, Finland
  • Address 2: Department of Clinical Neurophysiology, Kuopio University Hospital, POB 100, 70029 KYS, Kuopio, Finland
  • Email: petro.julkunen[at] (please fix the address before mailing!)

  • Date of birth: 11 June 1980

  • Current research interests: Modeling of articular cartilage and chondrocyte, Development of cartilage function, Cartilage structure, Neurophysiology, Transcranial magnetic stimulation.

  • Education:
    • Docent (Neurophysiology physics), 2009, University of Kuopio
    • Medical Physicist, 2009, University of Kuopio
    • Doctor of Philosophy University of Kuopio, (medical physics), 2008, (see pdf)
    • Master of Science in Engineering, Tampere University of Technology, (medical physics), 2004
    • Graduate of Finnish Secondary School (Porin suomalaisen yhteislyseon lukio, 1999)

  • Skills: Mechanical modeling, Neuromuscular research, Brain stimulation, Electromyography, Evoked potentials, Software programming, Image processing, Statistical analysis, EEG analysis. Qualified responsible supervisor proficiency for radiation safety in medicine according to the 18th article of Finnish radiation law (592/1991).

  • Language proficiency:
    • Finnish, native language
    • English, fluent
    • Swedish, fair

  • Membership in professional organizations:
    • Member, Association of Medical Physicists in Finland
    • Member, Finnish Association of Graduate Engineers
    • Member, Academic Association for Mathematics and Natural Sciences
    • Member, Finnish Society for Medical Physics and Medical Engineering
    • Member, Radiological Society of Finland
    • Member, European Society of Radiology
    • Member, Finnish Society of Clinical Neurophysiology
    • Member, Finnish Red Cross

  • Reviews for Scientific Journals:
    • Acta Biomaterialia
    • Annals of Neurology
    • Biomechanics and Modeling in Mechanobiology
    • Clinical Neurophysiology
    • Connective Tissue Research
    • Journal of Biomechanical Engineering
    • Journal of Biomechanics
    • Journal of Physiology
    • Journal of Neural Transmission
    • Journal of Neurology
    • Journal of Neuroscience Methods
    • Medical & Biological Engineering & Computing
    • Medical Engineering & Physics
    • NeuroImage
    • Neuroscience
    • Neurosurgery
    • Osteoarthritis and Cartilage
    • etc.

  • Hobbies: Gym, floorball, guitar playing.


(full papers, 50 previous)
  1. Tanska P , Julkunen P and Korhonen RK . A computational algorithm to simulate disorganization of collagen network in injured articular cartilage. Biomech Model Mechanobiol. 2017 Nov 24. pii: 10.1007/s10237-017-0986-3. doi:

  2. Kallioniemi E , Savolainen P , Jarnefelt G , Koskenkorva P , Karhu J and Julkunen P . Transcranial magnetic stimulation modulation of corticospinal excitability by targeting cortical I-waves with biphasic paired-pulses. Brain Stimul. 2017 Oct 20. pii: S1935-861X(17)30947-6. doi:

  3. Pitkanen M , Kallioniemi E and Julkunen P . Correction to: Extent and Location of the Excitatory and Inhibitory Cortical Hand Representation Maps: A Navigated Transcranial Magnetic Stimulation Study. Brain Topogr. 2017 Oct 14. pii: 10.1007/s10548-017-0600-0. doi:

  4. Pitkanen M , Kallioniemi E , Julkunen P , Nazarova M , Nieminen JO and Ilmoniemi RJ . Erratum to: Minimum-Norm Estimation of Motor Representations in Navigated TMS Mappings. Brain Topogr. 2017 Nov;30(6):723. doi: 10.1007/s10548-017-0587-6.

  5. Pitkanen M , Kallioniemi E and Julkunen P . Effect of inter-train interval on the induction of repetition suppression of motor-evoked potentials using transcranial magnetic stimulation. PLoS One. 2017 Jul 19;12(7):e0181663. doi: 10.1371/journal.pone.0181663.

  6. Pitkanen M , Kallioniemi E , Julkunen P , Nazarova M , Nieminen JO and Ilmoniemi RJ . Minimum-Norm Estimation of Motor Representations in Navigated TMS Mappings. Brain Topogr. 2017 Nov;30(6):711-722. doi: 10.1007/s10548-017-0577-8. Epub 2017

  7. Lasanen R , Malo MKH , Airaksinen O , Karhu J , Toyras J and Julkunen P . Infrared thermography reveals effect of working posture on skin temperature in office workers. Int J Occup Saf Ergon. 2017 Aug 9:1-7. doi: 10.1080/10803548.2017.1336299.

  8. Muraja-Murro A , Nieminen O , Julkunen P , Toyras J , Laitinen T and Mervaala E . Peri-apneic hemodynamic reactions in obstructive sleep apnea. Pathophysiology. 2017 Sep;24(3):197-203. doi: 10.1016/j.pathophys.2017.05.003.

  9. Kallioniemi E , Pitkanen M , Kononen M , Vanninen R and Julkunen P . Localization of cortical primary motor area of the hand using navigated transcranial magnetic stimulation, BOLD and arterial spin labeling fMRI. J Neurosci Methods. 2016 Nov 1;273:138-148. doi: 10.1016/j.jneumeth.2016.09.002.

  10. Julkunen P , Maatta S , Saisanen L , Kallioniemi E , Kononen M , Jakala P , Vanninen R and Vaalto S . Functional and structural cortical characteristics after restricted focal motor cortical infarction evaluated at chronic stage - Indications from a preliminary study. Clin Neurophysiol. 2016 Aug;127(8):2775-84. doi: 10.1016/j.clinph.2016.05.013.

  11. Jussen D , Zdunczyk A , Schmidt S , Rosler J , Buchert R , Julkunen P , Karhu J , Brandt S , Picht T and Vajkoczy P . Motor plasticity after extra-intracranial bypass surgery in occlusive cerebrovascular disease. Neurology. 2016 Jul 5;87(1):27-35. doi: 10.1212/WNL.0000000000002802. Epub 2016

  12. Julkunen P , Jarnefelt G , Savolainen P , Laine J and Karhu J . Facilitatory effect of paired-pulse stimulation by transcranial magnetic stimulation with biphasic wave-form. Med Eng Phys. 2016 Aug;38(8):813-7. doi: 10.1016/j.medengphy.2016.04.025. Epub

  13. Julkunen P , Kononen M , Maatta S , Tarkka IM , Hiekkala SH , Saisanen L , Vanninen R , Karhu J and Jakala P . Longitudinal study on modulated corticospinal excitability throughout recovery in supratentorial stroke. Neurosci Lett. 2016 Mar 23;617:88-93. doi: 10.1016/j.neulet.2016.02.014. Epub

  14. Kallioniemi E and Julkunen P . Alternative Stimulation Intensities for Mapping Cortical Motor Area with Navigated TMS. Brain Topogr. 2016 May;29(3):395-404. doi: 10.1007/s10548-016-0470-x. Epub 2016

  15. Kallioniemi E , Pitkanen M , Saisanen L and Julkunen P . Onset Latency of Motor Evoked Potentials in Motor Cortical Mapping with Neuronavigated Transcranial Magnetic Stimulation. Open Neurol J. 2015 Jul 31;9:62-9. doi: 10.2174/1874205X01509010062. eCollection

  16. Kallioniemi E , Paakkonen A and Julkunen P . Repetition suppression in transcranial magnetic stimulation-induced motor-evoked potentials is modulated by cortical inhibition. Neuroscience. 2015 Dec 3;310:504-11. doi: 10.1016/j.neuroscience.2015.09.056.

  17. Kallioniemi E , Kononen M , Saisanen L , Grohn H and Julkunen P . Functional neuronal anisotropy assessed with neuronavigated transcranial magnetic stimulation. J Neurosci Methods. 2015 Dec 30;256:82-90. doi: 10.1016/j.jneumeth.2015.08.028.

  18. Pitkanen M , Kallioniemi E and Julkunen P . Extent and Location of the Excitatory and Inhibitory Cortical Hand Representation Maps: A Navigated Transcranial Magnetic Stimulation Study. Brain Topogr. 2015 Sep;28(5):657-665. doi: 10.1007/s10548-015-0442-6. Epub 2015

  19. Saisanen L , Julkunen P , Kemppainen S , Danner N , Immonen A , Mervaala E , Maatta S , Muraja-Murro A and Kononen M . Locating and Outlining the Cortical Motor Representation Areas of Facial Muscles With Navigated Transcranial Magnetic Stimulation. Neurosurgery. 2015 Sep;77(3):394-405; discussion 405. doi:

  20. Khayyeri H , Gustafsson A , Heuijerjans A , Matikainen MK , Julkunen P , Eliasson P , Aspenberg P and Isaksson H . A fibre-reinforced poroviscoelastic model accurately describes the biomechanical behaviour of the rat Achilles tendon. PLoS One. 2015 Jun 1;10(6):e0126869. doi: 10.1371/journal.pone.0126869.

  21. Kallioniemi E , Kononen M and Julkunen P . Repeatability of functional anisotropy in navigated transcranial magnetic stimulation--coil-orientation versus response. Neuroreport. 2015 Jun 17;26(9):515-21. doi: 10.1097/WNR.0000000000000380.

  22. Muraja-Murro A , Mervaala E , Westeren-Punnonen S , Lepola P , Toyras J , Myllymaa S , Julkunen P , Kantanen AM , Kalviainen R and Myllymaa K . Forehead EEG electrode set versus full-head scalp EEG in 100 patients with altered mental state. Epilepsy Behav. 2015 Aug;49:245-9. doi: 10.1016/j.yebeh.2015.04.041. Epub 2015

  23. Kononen M , Tamsi N , Saisanen L , Kemppainen S , Maatta S , Julkunen P , Jutila L , Aikia M , Kalviainen R , Niskanen E , Vanninen R , Karjalainen P and Mervaala E . Non-invasive mapping of bilateral motor speech areas using navigated transcranial magnetic stimulation and functional magnetic resonance imaging. J Neurosci Methods. 2015 Jun 15;248:32-40. doi: 10.1016/j.jneumeth.2015.03.030.

  24. Kallioniemi E , Saisanen L , Pitkanen M , Kononen M , Karhu J and Julkunen P . Input-Output Characteristics of Late Corticospinal Silent Period Induced by Transcranial Magnetic Stimulation. J Clin Neurophysiol. 2015 Aug;32(4):346-51. doi: 10.1097/WNP.0000000000000177.

  25. Lasanen R , Julkunen P , Airaksinen O and Toyras J . Menthol concentration in topical cold gel does not have significant effect on skin cooling. Skin Res Technol. 2016 Feb;22(1):40-5. doi: 10.1111/srt.12226. Epub 2015 Mar 12.

  26. Hypponen J , Aikia M , Joensuu T , Julkunen P , Danner N , Koskenkorva P , Vanninen R , Lehesjoki AE , Mervaala E and Kalviainen R . Refining the phenotype of Unverricht-Lundborg disease (EPM1): a population-wide Finnish study. Neurology. 2015 Apr 14;84(15):1529-36. doi: 10.1212/WNL.0000000000001466. Epub

  27. Danso EK , Makela JT , Tanska P , Mononen ME , Honkanen JT , Jurvelin JS , Toyras J , Julkunen P and Korhonen RK . Characterization of site-specific biomechanical properties of human meniscus-Importance of collagen and fluid on mechanical nonlinearities. J Biomech. 2015 Jun 1;48(8):1499-507. doi: 10.1016/j.jbiomech.2015.01.048. Epub

  28. Lasanen R , Piippo-Savolainen E , Remes-Pakarinen T , Kroger L , Heikkila A , Julkunen P , Karhu J and Toyras J . Thermal imaging in screening of joint inflammation and rheumatoid arthritis in children. Physiol Meas. 2015 Feb;36(2):273-82. doi: 10.1088/0967-3334/36/2/273. Epub 2015

  29. Lofberg O , Julkunen P , Paakkonen A and Karhu J . The auditory-evoked arousal modulates motor cortex excitability. Neuroscience. 2014 Aug 22;274:403-8. doi: 10.1016/j.neuroscience.2014.05.060.

  30. Julkunen P . Methods for estimating cortical motor representation size and location in navigated transcranial magnetic stimulation. J Neurosci Methods. 2014 Jul 30;232:125-33. doi: 10.1016/j.jneumeth.2014.05.020.

  31. Kallioniemi E , Saisanen L , Kononen M , Awiszus F and Julkunen P . On the estimation of silent period thresholds in transcranial magnetic stimulation. Clin Neurophysiol. 2014 Nov;125(11):2247-52. doi: 10.1016/j.clinph.2014.03.012.

  32. Danner N , Julkunen P , Hypponen J , Niskanen E , Saisanen L , Kononen M , Koskenkorva P , Vanninen R , Kalviainen R and Mervaala E . Alterations of motor cortical excitability and anatomy in Unverricht-Lundborg disease. Mov Disord. 2013 Nov;28(13):1860-7. doi: 10.1002/mds.25615. Epub 2013 Aug 7.

  33. Korhonen RK , Julkunen P , Li L and van Donkelaar CC . Computational models of articular cartilage. Comput Math Methods Med. 2013;2013:254507. doi: 10.1155/2013/254507. Epub 2013

  34. Vaalto S , Julkunen P , Saisanen L , Kononen M , Maatta S and Karhu J . Long-term plasticity may be manifested as reduction or expansion of cortical representations of actively used muscles in motor skill specialists. Neuroreport. 2013 Aug 7;24(11):596-600. doi: 10.1097/WNR.0b013e3283628636.

  35. Julkunen P , Kallioniemi E , Kononen M and Saisanen L . Feasibility of automated analysis and inter-examiner variability of cortical silent period induced by transcranial magnetic stimulation. J Neurosci Methods. 2013 Jul 15;217(1-2):75-81. doi:

  36. Julkunen P , Wilson W , Isaksson H , Jurvelin JS , Herzog W and Korhonen RK . A review of the combination of experimental measurements and fibril-reinforced modeling for investigation of articular cartilage and chondrocyte response to loading. Comput Math Methods Med. 2013;2013:326150. doi: 10.1155/2013/326150. Epub 2013

  37. Julkunen P , Saisanen L , Kononen M , Vanninen R , Kalviainen R and Mervaala E . TMS-EEG reveals impaired intracortical interactions and coherence in Unverricht-Lundborg type progressive myoclonus epilepsy (EPM1). Epilepsy Res. 2013 Sep;106(1-2):103-12. doi: 10.1016/j.eplepsyres.2013.04.001.

  38. Tanska P , Turunen SM , Han SK , Julkunen P , Herzog W and Korhonen RK . Superficial collagen fibril modulus and pericellular fixed charge density modulate chondrocyte volumetric behaviour in early osteoarthritis. Comput Math Methods Med. 2013;2013:164146. doi: 10.1155/2013/164146. Epub 2013

  39. Lofberg O , Julkunen P , Tiihonen P , Paakkonen A and Karhu J . Repetition suppression in the cortical motor and auditory systems resemble each other--a combined TMS and evoked potential study. Neuroscience. 2013 Jul 23;243:40-5. doi: 10.1016/j.neuroscience.2013.03.060. Epub

  40. Kulkas A , Tiihonen P , Julkunen P , Mervaala E and Toyras J . Novel parameters indicate significant differences in severity of obstructive sleep apnea with patients having similar apnea-hypopnea index. Med Biol Eng Comput. 2013 Jun;51(6):697-708. doi: 10.1007/s11517-013-1039-4. Epub

  41. Kulkas A , Tiihonen P , Eskola K , Julkunen P , Mervaala E and Toyras J . Novel parameters for evaluating severity of sleep disordered breathing and for supporting diagnosis of sleep apnea-hypopnea syndrome. J Med Eng Technol. 2013 Feb;37(2):135-43. doi: 10.3109/03091902.2012.754509.

  42. Iivarinen JT , Korhonen RK , Julkunen P and Jurvelin JS . Experimental and computational analysis of soft tissue mechanical response under negative pressure in forearm. Skin Res Technol. 2013 Feb;19(1):e356-65. doi: 10.1111/j.1600-0846.2012.00652.x.

  43. Julkunen P , Saisanen L , Danner N , Awiszus F and Kononen M . Within-subject effect of coil-to-cortex distance on cortical electric field threshold and motor evoked potentials in transcranial magnetic stimulation. J Neurosci Methods. 2012;206(2):158-64. doi: 10.1016/j.jneumeth.2012.02.020. Epub

  44. Mononen ME , Mikkola MT , Julkunen P , Ojala R , Nieminen MT , Jurvelin JS and Korhonen RK . Effect of superficial collagen patterns and fibrillation of femoral articular cartilage on knee joint mechanics-a 3D finite element analysis. J Biomech. 2012 Feb 2;45(3):579-87. doi: 10.1016/j.jbiomech.2011.11.003. Epub

  45. Lotjonen P , Julkunen P , Tiitu V , Jurvelin JS and Toyras J . Ultrasound speed varies in articular cartilage under indentation loading. IEEE Trans Ultrason Ferroelectr Freq Control. 2011 Dec;58(12):2772-80. doi:

  46. Danner N , Kononen M , Saisanen L , Laitinen R , Mervaala E and Julkunen P . Effect of individual anatomy on resting motor threshold-computed electric field as a measure of cortical excitability. J Neurosci Methods. 2012 Jan 30;203(2):298-304. doi:

  47. Julkunen P , Saisanen L , Hukkanen T , Danner N and Kononen M . Does second-scale intertrial interval affect motor evoked potentials induced by single-pulse transcranial magnetic stimulation? Brain Stimul. 2012 Oct;5(4):526-32. doi: 10.1016/j.brs.2011.07.006. Epub 2011 Aug

  48. Iivarinen JT , Korhonen RK , Julkunen P and Jurvelin JS . Experimental and computational analysis of soft tissue stiffness in forearm using a manual indentation device. Med Eng Phys. 2011 Dec;33(10):1245-53. doi: 10.1016/j.medengphy.2011.05.015. Epub

  49. Danner N , Saisanen L , Maatta S , Julkunen P , Hukkanen T , Kononen M , Hypponen J , Kalviainen R and Mervaala E . Motor cortical plasticity is impaired in Unverricht-Lundborg disease. Mov Disord. 2011 Sep;26(11):2095-100. doi: 10.1002/mds.23813. Epub 2011 Jun 9.

  50. Julkunen P , Jauhiainen AM , Kononen M , Paakkonen A , Karhu J and Soininen H . Combining transcranial magnetic stimulation and electroencephalography may contribute to assess the severity of Alzheimer's disease. Int J Alzheimers Dis. 2011;2011:654794. doi: 10.4061/2011/654794. Epub 2011 May

(book sections)
  1. Julkunen P, Karhu J. Brain plasticity in neurosurgery. In: Navigated transcranial magnetic stimulation in neurosurgery, Krieg S (ed.), Springer, 2017, 267-285.
  2. Karhu J, Julkunen P. Therapeutic applications of nTMS in neurosurgery. In: Navigated transcranial magnetic stimulation in neurosurgery, Krieg S (ed.), Springer, 2017, 233-254.
Contact: +358 20 7872211 (Switch), email: bbc-l [at]