MOVE

Dr. M. (Melvyn) Roerdink
Faculty of Human Movement Sciences
Van der Boechorststraat 9
1081 BT Amsterdam
Tel: +31 (20) 59 88516
Room: D-621
Email: m.roerdink at vu.nl

RESEARCH

Rhythmic bodily movements are more or less automatically attracted to external acoustic rhythms (e.g., Snowball moving in time to pop music, Nature, demo). Such rhythms may thus be exploited to modulate rhythmic movements, like the frequency of cyclic movements through changes in the beats per minute of the external rhythm. My research focuses on rhythmic sensorimotor synchronization and the use of external rhythms in clinical gait rehabilitation.  Specifically, I examine the ‘anchoring’ of rhythmic movements to external rhythms with the aim to enhance the basic understanding of sensorimotor synchronization and to help reconcile dynamical systems and information-processing approaches to auditory-motor synchronization. I seek to translate the gathered theoretical insights to gait rehabilitation following stroke by investigating the efficacy of acoustic pacing to modulate cadence or symmetry and to evaluate gait adaptability via rhythm perturbations. This research led to the development of an instrumented treadmill for gait training and evaluation in rehabilitation practice (see illustrations below), allowing for online adaptations of rhythmic acoustic and visual cues contingent upon the actual walking pattern of the patient as well as for automatic registration of gait parameters -an important step towards more transparancy in rehabilitation practice. A commercial version of this treadmill is made available via ForceLink, Culemborg (the C-Mill). Furthermore, I am interested in dynamical signatures of pathology and expertise in postural sway and its relation to the amount of attention invested in postural control.

Current projects

• Acoustic and visual external rhythms provide an effective therapeutic means to modulate and train pathological gait. The stronger the coupling of gait to an external rhythm, the greater its therapeutic effect. This project, funded by a NWO Veni grant, compares the coupling strength of gait to either type of cueing in a group of healthy elderly with the aim to formulate recommendations for cueing in gait rehabilitation practice in  patients of similar age.
• Gait adaptability -the ability to adjust gait to changes in the environment- is an important aspect of prosthetic gait, yet difficult to assess in clinical settings. Funded by the OIM foundation and performed in collaboration with rehabilitation centers in Amsterdam (Reade) and Wijk aan Zee (Heliomare), this project aims to develop an efficient clinical protocol for evaluation of functional walking ability in rehabilitation practice.           
• Geriatric patients have increased fall risk and reduced confidence. Training of gait adaptability in a safe environment may help improve both factors. In a randomized clinical trial (FARE) in collaboration with Solis Zorggroep, fall risk and confidence in a group of patients recovering from a fall-related hip fracture receiving 6 weeks of treadmill training with a specific emphasis on practicing gait adjustments to environmental context will be compared with that of control groups receiving conventional gait training and dose-matched treadmill walking.
• In hemiplegic gait, step length typically differs between paretic and non-paretic sides. However, the direction of step-length asymmetry varies across patients.  This project seeks to unravel the functional origin of these directional variations in step-length asymmetry by examining its relation to differences in COM progression and forward leg swing between paretic and non-paretic steps.

 PUBLICATIONS [Last update: 06-03-2012]

Submitted for publication

• van Swigchem, R., Roerdink, M., Weerdesteyn, V., Geurts, A., Daffertshofer, A. (under revision). Persons post stroke have a reduced capacity to restore steady gait after a step modification. 
• Houdijk, H., van Ooijen, M.W., Kraal, J.J., Wiggerts, H.O., Polomski, W., Janssen, T.W., Roerdink, M. (revision submitted). Assessing gait adaptability in people with a unilateral amputation on a treadmill with visual context.
• Roerdink, M., Bank, P. J. M., Peper, C. E., Beek, P. J. (submitted). Anchoring in rhythmic in-phase and antiphase visuomotor tracking.

Patents 

• Device for displaying target indications for foot movements to persons with a walking disorder (2009, Inventors: M. Roerdink, P. J. Beek; Assignee: ForceLink BV). US2009246746-A1; EP2106779-A1; JP2009240775-A; NL1035236-C2.

International journals 

• Peper, C.E., Oorthuizen, J.K., Roerdink, M. (accepted). Attentional demands of cued walking in healthy young and elderly adults. Gait & Posture.
• Roerdink, M., Roeles, S., van der Pas, S.C., Bosboom, O., Beek, P.J. (2012). Evaluating asymmetry in prosthetic gait with step-length asymmetry alone is flawed. Gait & Posture, 35, 446-451. PubMed, ScienceDirect, PDF
• Roerdink, M., Hlavackova, P., Vuillerme, N. (2011). Effects of plantar-flexor muscle fatigue on the magnitude and regularity of center-of-pressure fluctuations. Experimental Brain Research, 212, 471-476. PubMed, Springer, PDF
• Roerdink, M., Bank, P. J. M., Peper, C. E., Beek, P. J. (2011). Walking to the beat of different drums: Practical implications for the use of acoustic rhythms in gait rehabilitation. Gait & Posture, 33, 690-694. PubMed, ScienceDirect, PDF
• Bank, P. J. M., Roerdink, M., Peper, C. E. (2011). Comparing the efficacy of metronome beeps and stepping stones to adjust gait: Steps to follow! Experimental Brain Research, 209, 159-169. PubMed, SpringerOpenAccess
• Roerdink, M., Beek, P. J. (2011). Understanding inconsistent step-length asymmetries across hemiplegic stroke patients: impairments and compensatory gait. Neurorehabilitation and Neural Repair, 25, 253-258. PubMed, SageOpenAccess
• Stins, J. F., Roerdink, M., Beek, P. J. (2011). To freeze or not to freeze? Affective and cognitive perturbations have markedly different effects on postural control. Human Movement Science, 30, 190-202. PubMed, ScienceDirect
• Roerdink, M., Hlavackova, P., Vuillerme, N. (2011). Center-of-pressure regularity as a marker for attentional investment in postural control: a comparison between sitting and standing postures. Human Movement Science, 30, 203-212. PubMed, ScienceDirect
• Stins, J. F., Michielsen, M. E., Roerdink, M., Beek, P. J. (2009). Sway regularity reflects attentional involvement in postural control: effects of expertise, vision and cognition. Gait & Posture, 30, 106-109. PubMed, ScienceDirect
• Roerdink, M., Lamoth, C. J. C., van Kordelaar, J., Elich, P., Konijnenbelt, M., Kwakkel, G., Beek, P. J. (2009). Rhythm perturbations in acoustically paced treadmill walking after stroke. Neurorehabilitation and Neural Repair, 23, 668-678. PubMed, Sage
• Roerdink, M., Geurts, A. C. H., De Haart, M., Beek, P. J. (2009). On the relative contribution of the paretic leg to the control of posture after stroke. Neurorehabilitation and Neural Repair, 23, 267-274. PubMed, Sage
• Boonstra, T. W., Daffertshofer, A., Roerdink, M., Flipse, I., Groenewoud, K., Beek, P. J. (2009). Bilateral motor unit synchronization of leg muscles during a simple dynamic balance task. European Journal of Neuroscience, 29, 613-622. PubMed, Wiley InterScience
• Roerdink, M., Coolen, H., Clairbois, B., Lamoth, C. J. C., Beek, P. J. (2008). Online gait event detection using a large force platform embedded in a treadmill. Journal of Biomechanics, 41, 2628-2632.  PubMed, ScienceDirect
• Boonstra, T. W., Roerdink, M., Daffertshofer, A., van Vugt, B., van Werven, G., Beek, P. J. (2008). Low alcohol doses reduce common 10-15 Hz input to bilateral leg muscles during quiet standing. Journal of Neurophysiology, 100, 2158-2164. PubMed, JNP
• Donker, S. F., Ledebt, A., Roerdink, M., Savelsbergh, G. J. P., Beek, P. J. (2008). Children with cerebral palsy exhibit greater and more regular postural sway than typically developing children. Experimental Brain Research, 184, 363-370. PubMed, SpringerLink
• Roerdink, M., Ophoff, E. D., Peper, C. E., Beek, P.J. (2008). Visual and musculoskeletal underpinnings of anchoring in rhythmic visuo-motor tracking. Experimental Brain Research, 184, 143-156. PubMed, SpringerLink
• Roerdink, M., Lamoth, C. J. C., Kwakkel, G., Van Wieringen, P. C. W., Beek, P. J. (2007). Gait coordination after stroke: benefits of acoustically paced treadmill walking. Physical Therapy, 87, 1009-1022. PubMed, PTJournal
• Donker, S. F., Roerdink, M., Greven, A. J., Beek, P. J. (2007). Regularity of center-of-pressure trajectories depends on the amount of attention invested in postural control. Experimental Brain Research, 181, 1-11. PubMed, SpringerLink
• Roerdink, M., De Haart, M., Daffertshofer, A., Donker, S. F., Geurts, A. C., Beek, P. J. (2006). Dynamical structure of center-of-pressure trajectories in patients recovering from stroke. Experimental Brain Research, 174, 256-269. PubMed, SpringerLink
• Roerdink, M., Peper, C. E., Beek, P. J. (2005). Effects of correct and transformed visual feedback on rhythmic visuo-motor tracking: tracking performance and visual search behavior. Human Movement Science, 24, 379-402. PubMed, ScienceDirect

Book Chapters

• Beek, P.J., Roerdink, M. (2012, in press). Evolving insights into motor learning and their implications for neurorehabilitation. In: Selzer, Clarke, Cohen, Kwakkel, Miller (Eds). Textbook of Neural Repair and Rehabilitation. Cambridge University Press.
• Michielsen, M., Stins, J. F., Roerdink, M., Beek, P. J. (2007). Effects of cognition and expertise on postural sway regularity. In Cummins-Sebree, S., Riley, M., Shockley, K. (Eds). Studies in Perception and Action IX. Lawrence Erlbaum.

Dissertation

• Roerdink, M. (2008). Anchoring: moving from theory to therapy, © M. Roerdink, Amsterdam. Cover, PDF, [email me for a hardcopy request].

Published abstracts and conference proceedings

• Roerdink, M., van Ooijen, M.W., Janssen, T.W.J., Beek, P.J. (2012). Development and implementation of an instrumented treadmill with visual context for functional gait rehabilitation. 7th World Congress for NeuroRehabilitation, Melbourne, Australia. Abstract
• Heeren J., van Ooijen, M.W., Janssen, T.W., Beek, P.J., Geurts, A.C., Roerdink, M., Weerdesteyn V. (2012). C-Mill therapy improves gait adaptability in the chronic phase after stroke. 7th World Congress for NeuroRehabilitation, Melbourne, Australia. Abstract
• Kerste, M.W., Houdijk, H., Janssen T.W.J., Roerdink, M. (2011). “Steps to follow” and “obstacles to avoid” in training functional walking ability: from technological innovation to clinical application. VRA Annual Congress, Ermelo, The Netherlands.
• Heeren, A., Kerste, M.W., Bongers, C., Roerdink, M., Weerdesteyn, V. (2011). The effect of C-Mill therapy on gait adaptability in chronic stroke patients: a proof of concept study. VRA Annual Congress, Ermelo, The Netherlands.
• Houdijk, H., Kerste, M., Kraal, J., Wiggerts, H., Polomski, W., Janssen, T., Roerdink, M. (2011). Gait adaptability in people walking with a transtibial or transfemoral prosthesis. Physiotherapy, 97, S1. abstract 
• Roerdink, M., Roeles, S., van der Pas, S.C., Beek, P.J. (2011). Assessing asymmetry in post-stroke and prosthetic gait in terms of step-length asymmetry alone is flawed! ISPGR, Akita, Japan (cancelled). abstract
• Houdijk, H., Kerste, M., Kraal, J., Wiggerts, H., Polomski, W., Janssen, T., Roerdink, M. (2010). An objective evaluation of gait adaptability in persons with transtibial or transfemoral prostheses. ISPO World Congres 2010, Leipzig, Germany. poster, Abstract
• Roerdink, M., Kerste, M.W. (2010). Het gebruik van cueing en obstakelontwijking in de training van loopvaardigheid. De fysiotherapeut: het muskulo-skeletale congres, Veldhoven, The Netherlands. samenvatting (in dutch)
• Roerdink, M., Lamoth, C.J.C, van Kordelaar, J., Kwakkel, G., Beek, P.J. (2009). Rhythm perturbations in acoustically paced walking after stroke: implications for gait training. ESMAC, London, UK. poster, abstract
• Boonstra, T. W., Roerdink, M., Breakspear, M., Daffertshofer, A. (2009). MU synchronization and synergies: correlations between EMGs. Progress in Motor Control, Marseille, France. PDF
• Roerdink, M., Geurts, A. C. H., De Haart, M., Beek, P. J. (2009). On the relative contribution of the paretic leg to the control of posture after stroke. ISPGR, Bologna, Italy. abstract
• Roerdink, M., Stins, J. F., Beek, P. J. (2009). Sway regularity indexes the amount of attention invested in postural control: a synthesis of empirical findings and guidelines for future examination. ISPGR Satelite Symposium, Pavia, Italy. abstract
• Roerdink, M. (2009). Geïnspireerd door revalidatie: technologische innovatie voor functionele looptraining. NIP voorjaarsconferentie, Egmond aan Zee, The Netherlands. abstract (in dutch)
• Roerdink, M., Coolen, B., Beek, P.J. (2009). Movement-dependent event control in gait rehabilitation: feedback, cueing, and obstacle presentation. 2nd Dutch BME Conference, Egmond aan Zee, The Netherlands. PDF
• Roerdink, M., Bank, P. J. M., Peper, C. E., Beek, P. J. (2008). Unraveling the informational basis of anchoring in rhythmic visuomotor tracking. International Journal of Sport Psychology, 41(4), S102-103.
• de Poel, H. J., Roerdink, M., Peper, C. E., Beek, P. J. (2008). The effect of movement amplitude on bimanual coordination: Comparison of three stability measures. International Journal of Sport Psychology, 41(4), S59-60.  
• Roerdink, M. (2008). Valid online gait event detection in treadmill walking: a prerequisite for event control in gait rehabilitation. 2nd Summer School on Advanced Technologies for Neuromotor Assessment and Rehabilitation, Bologna, Italy. 
• Roerdink, M., Lamoth, C. J. C., van Kordelaar, J., Kwakkel, G., Beek, P. J. (2008). Gait after stroke benefits from acoustic pacing: an inquiry in possible underlying principles. Parkinsonism & Related Disorders, 14, S66.
• Lamoth, C. J. C., Roerdink, M., Beek, P. J. (2007). Acoustically-paced treadmill walking requires more attention than unpaced treadmill walking in healthy young adults. Gait & Posture, 26, S96-S97.
• Roerdink, M., De Haart, M., Daffertshofer, A., Donker, S. F., Geurts, A. C., Beek, P. J. (2007). Sway regularity depends on the amount of attention invested in postural control: findings from patients recovering from stroke. European Workshop on Movement Science, Amsterdam, The Netherlands.
• Roerdink, M., Ophoff, E. D., Peper, C. E., Beek, P.J. (2007). Informational and musculoskeletal underpinnings of anchoring. European Workshop on Movement Science, Amsterdam, The Netherlands.
• Roerdink, M., Lamoth, C. J. C., Kwakkel, G., Van Wieringen, P. C. W., Beek, P. J. (2007). Acoustically-paced treadmill walking following stroke. European Workshop on Movement Science, Amsterdam, The Netherlands.
• Lamoth, C. J. C., Roerdink, M., Beek, P. J. (2007). Acoustically-paced treadmill walking requires more attention than unpaced treadmill walking in healthy young adults. European Workshop on Movement Science, Amsterdam, The Netherlands.
• Roerdink, M., Lamoth, C. J. C., Kwakkel, G., Van Wieringen, P. C. W., Beek, P. J. (2006). Auditory-paced walking following stroke. Gait & Posture, 24, S95-S97.
• Roerdink, M., Ophoff, E. D., Peper, C. E., Beek, P.J. (2006). Anchoring: a window into the control of perceptual-motor tasks. 9th European Workshop on Ecological Psychology, Groningen, The Netherlands.
• Roerdink, M., De Haart, M., Donker, S. F., Geurts, A. C. H., Beek, P. J. (2005). Postural sway complexity changes with recovery after stroke: Findings from dynamical analyses. Gait & Posture, 21, S110.
• Roerdink, M., Donker, S. F., Beek, P. J. (2005). A methodological note on the sway-density curve: Number of peaks scales with cut-off frequency. Gait & Posture, 21, S150.
• Roerdink, M., Peper, C. E., Beek, P.J. (2004). The role of feedback in rhythmic visuomotor tracking: Stability and visual search patterns. 8th European Workshop on Ecological Psychology, Verona, Italy.