Functional Ultrasound Imaging System for functional-connectivity industry-Monitoring and Testing
Functional ultrasound (fUS) is utilized in resting-state functional connectivity mapping as a technique to study intrinsic brain networks by detecting blood flow fluctuations. fUS boasts a higher spatial and temporal resolution compared to BOLD fMRI and provides greater sensitivity, making it effective in examining neuropsychiatric disorders and aiding early diagnosis. The device generates connectivity matrices both in 2D and 3D quickly, analyzing a single coronal plane or determining overall connectivity between slices respectively. fUS has demonstrated applications in pathological models by revealing how conditions affect brain connectivity throughout varied studies such as oxytocin's role or pain sensitivity in rats. It eliminates biases linked with anesthesia by enabling connectivity data collection from awake, freely-moving mice. This feature is beneficial for exploring the impact of anesthetics and for the study of genetically modified models, hence broadening the scope of neuroimaging research.
2D connectivity matrices
3D connectivity matrices
Seed-based correlation mapping
Another way of visualizing brain activity relationships is by correlating voxel activity across the whole brain with the activity of a small ‘seed’ region – known as seed-based (or ROI-based) functional connectivity.
This approach is not so dependent on the segmentation of the brain into functional regions, since you only need to define a single region.
Functional connectivity in pathological models
A different manifestation of functional connectivity is looking at how differences relevant to animal pathologies influence connectivity across the whole brain.
For example, functional ultrasound has been used to study the role of oxytocin in rat pups (Mairesse et al., Glia, 2019) and to investigate sensitivity to inflammatory pain in anesthetized rats, as shown here.