"Age differences in flexibility in Motor Control"

Im Rahmen des Neurowissenschaftlichen Kolloquiums hält Herr Dr. Raoul Bongers /Universität Groningen, Niederlande am 03.02.15 einen Vortrag zum Thema
“Age differences in flexibility in Motor Control”.
Vortragsort ist der Rektoratsbesprechungsraum im Hauptgebäude 2. Stock von14:00 – 15:30 Uhr.  

Colloqium Cologne 3 February 2015
Age differences in flexibility in Motor Control
Raoul M. Bongers, Christian Greve, Tibor Hortobágyi

Center for Human Movement Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands

The capacity to coordinate movements in different ways depending on task demands or variations in internal constraints is characteristic of human behavior and is coined flexibility. In this lecture we would like to address properties of this flexibility and how it is affected by age. Flexibility is operationalized using the Uncontrolled Manifold (UCM) method (Latash, Scholz & Schöner, 2007). Within the UCM analysis it is assumed that the neuromuscular system acts in a state space of elemental variables (e.g. joint angles) and makes use of all available degrees of freedom to enable stable but flexible control of task important performance variables. The method allows distinguishing variability of elemental variables in stabilizing and de-stabilizing variability. The ratio between the two is an indicator of flexibility. We showed in a sit-to-stand task that old adults showed more flexibility than young adults (Greve et al., 2013) to stabilize ground reaction forces. We hypothesized that the aging neuromuscular system employed this strategy to compensate for strength deficits. To study the generality of this finding we performed follow-up experiments using a reaching task. We manipulated load demands and accuracy demands to further understand the origin of the effects found in Greve et al. (2013). In an experiment with just young adults we showed no effect of accuracy demands on flexibility but a proportional increase in stabilizing and de-stabilizing variability with larger loads (Greve et al., 2014). Preliminary analyses on a reaching experiment where young and old adults reached to a target under varying load and accuracy demands showed no differences between age groups.

Greve, C., Hortobágyi, T., & Bongers R.M. (2014). Physical demand but not dexterity is associated with motor flexibility during rapid reaching in healthy young adults. Revision submitted (PLoS One)

Greve, C., Zijlstra, W., Hortobágyi, T., & Bongers, R. M. (2013). Not all is lost: Old adults retain flexibility in motor behaviour during sit-to-stand. PloS One, 8(10), e77760. 

Latash, M.L., Scholz, J.P., & Schöner, G. (2007). Toward a new theory of motor synergies. Motor Control, 11, 276–308.