Lower Limb Movement Preparation in Chronic Stroke

A Pilot Study Toward an fNIRS-BCI for Gait Rehabilitation

  • Rea, Massimiliano PhD
  • Rana, Mohit MSc
  • Lugato, Nicola
  • Terekhin, Pavel MD
  • Gizzi, Leonardo PhD
  • Brötz, Doris
  • Fallgatter, Andreas PhD
  • Birbaumer, Niels PhD
  • Sitaram, Ranganatha PhD
  • Caria, Andrea PhD

  • 1Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany

    2Department of General Psychiatry, University of Tübingen, Tübingen, Germany

    3University Hospital Göttingen, Göttingen, Germany

    4Istituto di Ricovero e Cura a Carattere Scientifico, Venezia, Lido, Italy

    5University of Florida, Gainesville, FL, USA

    6Sri Chitra Tirunal Institute of Medical Sciences and Technology, Trivandrum, India

Corresponding Author: Massimiliano Rea, Department of General Psychiatry, University of Tübingen, Osianderstraße 24, 72076 Tübingen, Germany. Email: [email protected]

Neurorehabilitation and Neural Repair 28(6):p 564-575, July-August 2014. | DOI: 10.1177/1545968313520410

Background.

Thus far, most of the brain-computer interfaces (BCIs) developed for motor rehabilitation used electroencephalographic signals to drive prostheses that support upper limb movement. Only few BCIs used hemodynamic signals or were designed to control lower extremity prostheses. Recent technological developments indicate that functional near-infrared spectroscopy (fNIRS)-BCI can be exploited in rehabilitation of lower limb movement due to its great usability and reduced sensitivity to head motion artifacts.

Objective.

The aim of this proof of concept study was to assess whether hemodynamic signals underlying lower limb motor preparation in stroke patients can be reliably measured and classified.

Methods.

fNIRS data were acquired during preparation of left and right hip movement in 7 chronic stroke patients.

Results.

Single-trial analysis indicated that specific hemodynamic changes associated with left and right hip movement preparation can be measured with fNIRS. Linear discriminant analysis classification of totHB signal changes in the premotor cortex and/or posterior parietal cortex indicated above chance accuracy in discriminating paretic from nonparetic movement preparation trials in most of the tested patients.

Conclusion.

The results provide first evidence that fNIRS can detect brain activity associated with single-trial lower limb motor preparation in stroke patients. These findings encourage further investigation of fNIRS suitability for BCI applications in rehabilitation of patients with lower limb motor impairment after stroke.

Copyright ©2014Sage Publications