Neurofeedback using real-time near-infrared spectroscopy enhances motor imagery related cortical activation

• Published in: PloS one Vol. 7; no. 3; p. e32234
• Main Authors: Mihara, Masahito, Miyai, Ichiro, Hattori, Noriaki, Hatakenaka, Megumi, Yagura, Hajime, Kawano, Teiji, Okibayashi, Masaki, Danjo, Nobuyoshi, Ishikawa, Akihiro, Inoue, Yoshihiro, Kubota, Kisou
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 02.03.2012; Public Library of Science (PLoS)
• Subjects: Activation; Adult; Artificial neural networks; Biofeedback; Biology; Brain research; Cerebral Cortex - physiology; Clinical trials; Cortex (premotor); Electroencephalography; Emulation; Experiments; Feasibility; Feasibility studies; Feedback; Female; Glycosylated hemoglobin; Hemoglobin; Hemoglobins - metabolism; Humans; I.R. radiation; Image enhancement; Imagery (Psychotherapy) - methods; Imagination - physiology; Infrared imagery; Infrared spectra; Infrared spectroscopy; Male; Medical imaging; Medical research; Medicine; Mental task performance; Motor Skills; Motor task performance; Movement - physiology; Near infrared radiation; Near infrared spectroscopy; Neural networks; Neurofeedback - methods; Oxygen - chemistry; Oxyhemoglobins - metabolism; Patients; Psychomotor Performance - physiology; R&D; Real time; Rehabilitation; Research & development; Self-assessment; Spectroscopy; Spectroscopy, Near-Infrared - methods; Spectrum analysis; Stroke; Stroke - physiopathology; Japan
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0032234

Accumulating evidence indicates that motor imagery and motor execution share common neural networks. Accordingly, mental practices in the form of motor imagery have been implemented in rehabilitation regimes of stroke patients with favorable results. Because direct monitoring of motor imagery is difficult, feedback of cortical activities related to motor imagery (neurofeedback) could help to enhance efficacy of mental practice with motor imagery. To determine the feasibility and efficacy of a real-time neurofeedback system mediated by near-infrared spectroscopy (NIRS), two separate experiments were performed. Experiment 1 was used in five subjects to evaluate whether real-time cortical oxygenated hemoglobin signal feedback during a motor execution task correlated with reference hemoglobin signals computed off-line. Results demonstrated that the NIRS-mediated neurofeedback system reliably detected oxygenated hemoglobin signal changes in real-time. In Experiment 2, 21 subjects performed motor imagery of finger movements with feedback from relevant cortical signals and irrelevant sham signals. Real neurofeedback induced significantly greater activation of the contralateral premotor cortex and greater self-assessment scores for kinesthetic motor imagery compared with sham feedback. These findings suggested the feasibility and potential effectiveness of a NIRS-mediated real-time neurofeedback system on performance of kinesthetic motor imagery. However, these results warrant further clinical trials to determine whether this system could enhance the effects of mental practice in stroke patients.