Mapping Whole-Brain Auditory Activation with 3T Multi-Echo fMRI at the Group and Individual-Subject Level

Area of Science:

• Neuroimaging
• Auditory Neuroscience
• Functional Magnetic Resonance Imaging (fMRI)

Background:

• Magnetic Resonance Imaging (MRI) is crucial for non-invasively studying the auditory system.
• Traditional BOLD fMRI methods have limitations including specialized hardware needs, long scan times, and reliance on group averaging.
• Whole-brain multi-echo (ME) fMRI has emerged as a technique to mitigate these limitations, improving data quality and scan efficiency.

Purpose of the Study:

• To propose and evaluate the use of a readily available ME whole-brain acquisition and denoising techniques for auditory system analysis.
• To compare group-level and individual-subject precision mapping approaches for identifying auditory activation.
• To demonstrate the benefits of ME fMRI for high-resolution functional mapping aligned to individual anatomy.

Main Methods:

• Utilized whole-brain multi-echo (ME) fMRI acquisition and ME denoising strategies.
• Performed both whole-brain and region-specific analyses to detect auditory activation.
• Employed dense-sampling strategies for precision mapping of neural activity in individual subjects.

Main Results:

• Group-level analysis revealed bilateral auditory activation in cortical regions and unilateral activation in cerebellar lobules VIIb/VIIIa, with region-specific analysis identifying additional unilateral thalamic and brainstem activation.
• Individual-subject precision mapping combined with ME denoising enhanced sensitivity, detecting bilateral activation across cortical, cerebellar, thalamic, and brainstem regions.
• The study successfully demonstrated improved alignment of individual functional responses to specific anatomy using ME methods and whole-brain precision mapping.

Conclusions:

• Multi-echo (ME) fMRI techniques, particularly when combined with whole-brain acquisition and precision mapping, significantly enhance the sensitivity and resolution of auditory system functional imaging.
• This approach offers a powerful tool for both group and individual subject analyses, overcoming limitations of conventional fMRI.
• Precision mapping with ME denoising facilitates detailed, anatomically aligned functional mapping of the auditory system at the individual level.