Advances in resting state fMRI acquisitions for functional connectomics

Area of Science:

• Neuroimaging
• Neuroscience
• Medical Physics

Background:

• Resting state functional magnetic resonance imaging (rs-fMRI) measures spontaneous brain activity via blood oxygen level dependent (BOLD) signal fluctuations.
• These low-frequency oscillations reveal intrinsic brain networks and spatiotemporal organization, potentially reflecting neural activity.
• Understanding rs-fMRI acquisition is crucial for accurate brain network analysis.

Purpose of the Study:

• To review current and emerging acquisition techniques for rs-fMRI data.
• To discuss methods for enhancing spatial specificity and exploring challenging brain regions.
• To provide recommendations for optimal rs-fMRI acquisition strategies across various applications.

Main Methods:

• Overview of common and advanced rs-fMRI acquisition strategies, including ultra-high field and dedicated hardware.
• Discussion of specialized sequences for rapid acquisition and multi-echo imaging.
• Exploration of acquisition methods sensitive to Cerebral Blood Flow (CBF) and Cerebral Blood Volume (CBV) for improved spatial specificity.

Main Results:

• Acquisition techniques vary in their ability to capture BOLD signal characteristics and spatial resolution.
• Advanced methods, including CBF/CBV-weighted acquisitions, offer potential for more spatially precise network mapping.
• Specific strategies are being developed for challenging regions like neocortical laminae and subcortical white matter.

Conclusions:

• Optimizing rs-fMRI acquisition is key to maximizing the information gained about intrinsic brain networks.
• Emerging techniques and tailored strategies enhance the study of complex brain structures and networks.
• Recommendations are provided to guide the selection of appropriate acquisition protocols for diverse rs-fMRI applications.