Transcranial brain atlas based on photon measurement density function in a triple-parameter standard channel space

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Imaging

Background:

• Functional near-infrared spectroscopy (fNIRS) is a key brain imaging tool.
• Limited anatomical information in fNIRS hinders signal localization and montage design.
• Current methods use standard head models, which lack individual anatomical accuracy.

Purpose of the Study:

• To develop a more generalizable spatial localization tool for fNIRS.
• To overcome limitations of existing PMDF-based localization methods.
• To create a continuous standard channel space and a PMDF-based transcranial brain atlas (PMDF-TBA).

Main Methods:

• Calculated photon measurement density functions (PMDFs) using MRI data from 48 adults.
• Constructed the PMDF-TBA, including group-averaged channel sensitivities to gray matter and brain regions (Brodmann, AAL2, LPBA40).
• Evaluated PMDF-TBA's prediction accuracy for unseen individuals' sensitivities.

Main Results:

• The PMDF-TBA demonstrated superior prediction ability compared to methods using single standard head models.
• The atlas provides a more generalizable approach to fNIRS spatial localization.
• Group-averaged sensitivities were calculated for various brain regions and gray matter.

Conclusions:

• The PMDF-TBA enhances fNIRS spatial localization accuracy.
• It optimizes optode montage design and improves sensitivity in target brain regions.
• This tool facilitates fNIRS applications in neuroscience research, especially without individual MRI data.