Qualitative and Comparative Cortical Activity Data Analyses from a Functional Near-Infrared Spectroscopy Experiment...

Area of Science:

• Neuroscience
• Medical Imaging
• Rehabilitation Medicine

Background:

• Neuroimaging is crucial for assessing neurological conditions before and after interventions like surgery or rehabilitation.
• Functional near-infrared spectroscopy (fNIRS) measures cortical activity via hemoglobin levels, offering greater flexibility than fMRI for sensorimotor tasks.
• Standardized analysis methods for fNIRS data are lacking, hindering consistent research and clinical application.

Purpose of the Study:

• To present qualitative and comparative analytical methods for multi-channel fNIRS data from block-design experiments.
• To establish a standardized approach for analyzing fNIRS data in pre- vs. post-intervention studies.
• To demonstrate the utility of these methods for evaluating neurological disorders.

Main Methods:

• Utilized NIRS-SPM software for mass-univariate analysis based on the generalized linear model for qualitative assessment.
• Employed a non-invasive 3D digitizer to accurately map fNIRS channel locations on the brain.
• Applied a multi-channel hierarchical mixed model to statistically compare hemoglobin level changes between pre- and post-intervention sessions.

Main Results:

• NIRS-SPM provided qualitative visualization of brain activation during sensorimotor tasks.
• Accurate anatomical localization of fNIRS channels was achieved using 3D digitization.
• Statistical analysis confirmed significant changes in hemoglobin levels post-intervention, validated by the mixed-effects model.

Conclusions:

• The proposed analytical methods offer a standardized approach for fNIRS data interpretation.
• These methods facilitate robust pre- vs. post-intervention analysis in neurological studies.
• The approach is applicable to diverse neurological conditions, including movement disorders, cerebrovascular diseases, and neuropsychiatric disorders.