Thesis defense Freek Nieuwhof (Donders series 288)
27 October 2017
Promotors: Prof. dr. M. Olde Rikkert, Prof. dr. B. Bloem
Copromotors: Dr. M. Reelick, Dr. R. Helmich
The complexity of walking: cognitive control of gait in aging and Parkinson's disease
Many older adults, especially those with Parkinson’s disease, experience difficulties when walking. Complex situations that require another action in addition to walking itself (talking, thinking or navigating) often lead to falls. In this thesis, we investigated the causes underlying these walking difficulties. One interesting result was that older adults with Parkinson’s disease did not show increased activity in frontal brain areas during complex activity compared to simple walking. Walking probably demands much attention (reflected in increased frontal activity), which cannot be further increased in more complex situations. In addition, we found that deep within the brain (in the putamen), older adults with Parkinson’s disease showed altered activity during complex situations. It may be that Parkinson‘s disease causes neural networks that normally are tidily segregated to become intertwined. This could be another mechanism underlying the inability to combine two tasks. In older adults without Parkinson’s disease, we did not find altered brain activity. The results of this thesis could provide new insights and opportunities for development of therapies to improve walking, especially in the case of Parkinson’s disease.