Natalie Mrachacz-Kersting from Aalborg University is visiting Aarhus and will give a CFIN and MIB guest talk on: "An associative Brain-Computer-Interface for the rehabilitation of stroke patients".

14.06.2018 | Henriette Blæsild Vuust

Natalie Mrachacz-Kersting
Aalborg University

Title: An associative Brain-Computer-Interface for the rehabilitation of stroke patients

Abstract:

A brain-computer interface (BCI) uses brain signals to drive external devices [1]. The signals are acquired using either implanted electrodes or non-invasive scalp electrodes. Traditionally, research within BCI has targeted its use as a communication and gaming tool. For example, patients with advanced amyotrophic lateral sclerosis (ALS) use BCIs to communicate with their surrounding environment. However, over the last 10 years, the field of BCI has been expanding rapidly with researchers seeking to widen the application to a larger population. BCI systems designed for neuromodulation in patients suffering from a central nervous system lesion is a prime example of such an endeavor. Using a BCI for neuromodulation requires that the protocol closely matches those steps involved in the motor learning process. However, the underlying mechanisms of motor learning in humans remain elusive though several possibilities have been suggested. Of these, the most promising was proposed by Hebb [2], who advocated that synaptic strength is increased when two inputs from two sources arrive at the post-synaptic cell in synchrony. If this occurs repetitively with the necessary intensity, synaptic strength is increased.

Here I will present applications of BCIs for neuromodulation in stroke rehabilitation. This application is based on associative plasticity. The activation of relevant brain areas generated by a subject’s intention to move is detected, interpreted and used to drive an electrical stimulator or a robot. This stimulates or passively moves the required muscles to produce the intended movement [3]. In stroke rehabilitation for motor function, this intervention has been shown to activate and reorganize the brain areas related to the planning and execution of voluntary movements [4]. The series of studies I will present, underline the potential of BCI systems for modulating cortical excitability by inducing targeted plasticity.

1. J. R. Wolpaw, "Brain-computer interfaces," Handb.Clin.Neurol., vol. 110, pp. 67-74, 2013.
2. D. O. Hebb, The Organization of Behavior: A Neuropsychological Theory. Mahwah, NJ: Lawrence Erlbaum Associates Inc, 1949.
3. N. Mrachacz-Kersting, S. R. Kristensen, I. K. Niazi and D. Farina, "Precise temporal association between cortical potentials evoked by motor imagination and afference induces cortical plasticity," J. Physiol., vol. 590, pp. 1669-1682, Apr 1, 2012.
4. N. Mrachacz-Kersting, N. Jiang, A. J. Stevenson, I. K. Niazi, V. Kostic, A. Pavlovic, S. Radovanovic, M. Djuric-Jovicic, F. Agosta, K. Dremstrup and D. Farina, "Efficient neuroplasticity induction in chronic stroke patients by an associative brain-computer interface," J. Neurophysiol., vol. 115, pp. 1410-1421, Mar 1, 2016. 

Read more at: http://vbn.aau.dk/en/persons/natalie-mrachaczkersting(8c03c448-9888-458b-b40a-81ed1129f04b).html