title: Dose-response relationships using brain-computer interface technology impact stroke rehabilitation.
abstract: Brain-computer interfaces (BCIs) are an emerging novel technology for stroke rehabilitation. Little is known about how dose-response relationships for BCI therapies affect brain and behavior changes. We report preliminary results on stroke patients (n = 16, 11 M) with persistent upper extremity motor impairment who received therapy using a BCI system with functional electrical stimulation of the hand and tongue stimulation. We collected MRI scans and behavioral data using the Action Research Arm Test (ARAT), 9-Hole Peg Test (9-HPT), and Stroke Impact Scale (SIS) before, during, and after the therapy period. Using anatomical and functional MRI, we computed Laterality Index (LI) for brain activity in the motor network during impaired hand finger tapping. Changes from baseline LI and behavioral scores were assessed for relationships with dose, intensity, and frequency of BCI therapy. We found that gains in SIS Strength were directly responsive to BCI therapy: therapy dose and intensity correlated positively with increased SIS Strength (p ≤ 0.05), although no direct relationships were identified with ARAT or 9-HPT scores. We found behavioral measures that were not directly sensitive to differences in BCI therapy administration but were associated with concurrent brain changes correlated with BCI therapy administration parameters: therapy dose and intensity showed significant (p ≤ 0.05) or trending (0.05 < p < 0.1) negative correlations with LI changes, while therapy frequency did not affect LI. Reductions in LI were then correlated (p ≤ 0.05) with increased SIS Activities of Daily Living scores and improved 9-HPT performance. Therefore, some behavioral changes may be reflected by brain changes sensitive to differences in BCI therapy administration, while others such as SIS Strength may be directly responsive to BCI therapy administration. Data preliminarily suggest that when using BCI in stroke rehabilitation, therapy frequency may be less important than dose and intensity.
authors.affiliation: Department of Radiology, University of Wisconsin Hospital & Clinics, University of Wisconsin-Madison, Madison WI, USA ; Medical Scientist Training Program, University of Wisconsin-Madison, Madison WI, USA ; Neuroscience Training Program, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Brittany M
authors.initials: BM
authors.lastname: Young
authors.affiliation: Department of Radiology, University of Wisconsin Hospital & Clinics, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Zack
authors.initials: Z
authors.lastname: Nigogosyan
authors.affiliation: Neuroscience Training Program, University of Wisconsin-Madison, Madison WI, USA ; Department of Biomedical Engineering, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Léo M
authors.initials: LM
authors.lastname: Walton
authors.affiliation: Department of Radiology, University of Wisconsin Hospital & Clinics, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Alexander
authors.initials: A
authors.lastname: Remsik
authors.affiliation: Department of Radiology, University of Wisconsin Hospital & Clinics, University of Wisconsin-Madison, Madison WI, USA ; Department of Biomedical Engineering, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Radiology, University of Wisconsin Hospital & Clinics, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Veena A
authors.initials: VA
authors.lastname: Nair
authors.affiliation: Department of Biomedical Engineering, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Mitchell E
authors.initials: ME
authors.lastname: Tyler
authors.affiliation: Department of Kinesiology and Department of Medicine, University of Wisconsin-Madison, Madison WI, USA ; Department of Neurology, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Dorothy F
authors.initials: DF
authors.lastname: Edwards
authors.affiliation: Department of Orthopedics and Rehabilitation, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Kristin
authors.initials: K
authors.lastname: Caldera
authors.affiliation: Department of Neurology, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Justin A
authors.initials: JA
authors.lastname: Sattin
authors.affiliation: Neuroscience Training Program, University of Wisconsin-Madison, Madison WI, USA ; Department of Biomedical Engineering, University of Wisconsin-Madison, Madison WI, USA ; Department of Neurosurgery, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Justin C
authors.initials: JC
authors.lastname: Williams
authors.affiliation: Department of Radiology, University of Wisconsin Hospital & Clinics, University of Wisconsin-Madison, Madison WI, USA ; Medical Scientist Training Program, University of Wisconsin-Madison, Madison WI, USA ; Neuroscience Training Program, University of Wisconsin-Madison, Madison WI, USA ; Department of Neurology, University of Wisconsin-Madison, Madison WI, USA ; Department of Psychology and Department of Psychiatry, University of Wisconsin-Madison, Madison WI, USA.
authors.forename: Vivek
authors.initials: V
authors.lastname: Prabhakaran
keywords: BCI therapy; UE motor recovery; brain–computer interface; dose-response; fMRI; stroke rehabilitation