A method for using blocked and event-related fMRI data to study "resting state" functional connectivity.

Area of Science:

• Neuroimaging
• Cognitive Neuroscience
• Systems Neuroscience

Background:

• Resting state functional connectivity MRI (fcMRI) is vital for understanding brain networks in various populations.
• Existing task-based fMRI datasets offer a potential resource for resting state analyses, reducing the need for new data acquisition.

Purpose of the Study:

• To evaluate the suitability of using existing task-based fMRI data for resting state functional connectivity (rs-fcMRI) analysis.
• To compare the quality of rs-fcMRI data derived from interleaved resting blocks versus residuals from event-related designs against continuous resting state data.

Main Methods:

• Functional connectivity was assessed using correlation analysis.
• Resting epochs from mixed blocked/event-related fMRI designs were compared with residuals from event-related designs.
• Both data types were compared against standard continuous resting state data.

Main Results:

• Interleaved resting periods from blocked designs demonstrated high qualitative and quantitative similarity to continuous resting state data.
• Residuals from event-related designs, while qualitatively similar, exhibited significant quantitative differences compared to continuous resting state data.

Conclusions:

• Interleaved resting state data from blocked or mixed blocked/event-related fMRI designs are well-suited for rs-fcMRI analyses.
• Residuals from event-related fMRI data can be used for rs-fcMRI, but findings require careful interpretation due to quantitative dissimilarities.