title: Separation of the global and local components in functional near-infrared spectroscopy signals using principal component spatial filtering.
abstract: Global systemic effects not specific to a task can be prominent in functional near-infrared spectroscopy (fNIRS) signals and the separation of task-specific fNIRS signals and global nonspecific effects is challenging due to waveform correlations. We describe a principal component spatial filter algorithm for separation of the global and local effects. The effectiveness of the approach is demonstrated using fNIRS signals acquired during a right finger-thumb tapping task where the response patterns are well established. Both the temporal waveforms and the spatial pattern consistencies between oxyhemoglobin and deoxyhemoglobin signals are significantly improved, consistent with the basic physiological basis of fNIRS signals and the expected pattern of activity associated with the task.
authors: Yale School of Medicine , Department of Psychiatry, New Haven, Connecticut 06511, United States.
authors: Xian
authors: X
authors: Zhang
authors: Yale School of Medicine , Department of Psychiatry, New Haven, Connecticut 06511, United States.
authors: Jack Adam
authors: JA
authors: Noah
authors: Yale School of Medicine, Department of Psychiatry, New Haven, Connecticut 06511, United States; Yale School of Medicine, Department of Neuroscience, New Haven, Connecticut 06511, United States; Yale School of Medicine, Department of Comparative Medicine, New Haven, Connecticut 06511, United States; University College London, Department of Medical Physics and Biomedical Engineering, Gower Street, London WC1E 6BT, United Kingdom.
authors: Joy
authors: J
authors: Hirsch
keywords: finger thumb tapping; functional near-infrared spectroscopy; global component; spatial filter