Reproducibility of single-subject functional connectivity measurements

Area of Science:

• Neuroscience
• Medical Imaging
• Brain Connectivity

Background:

• Resting-state functional connectivity (rsFC) is crucial for characterizing neurological and developmental conditions.
• Determining the necessary imaging duration for reproducible rsFC measurements is vital for single-subject diagnostics.

Purpose of the Study:

• To ascertain the minimum imaging time required for reliable quantitative rsFC measurements.
• To establish the duration needed for a dependable single-subject diagnostic test.

Main Methods:

• Acquired 100 five-minute BOLD scans from one subject at rest or watching videos.
• Compared subject data with rsFC scans from 36 healthy controls.
• Analyzed correlations between 64 spherical regions of interest.

Main Results:

• Reliable rsFC estimates converged proportionally to 1/sqrt(n) for both single-subject and group data.
• Significant reliability improvements were observed with ≤25 minutes of imaging time.
• Individual connectivity "fingerprints" diverged around 15 minutes, with accuracy increasing up to 4 hours.

Conclusions:

• Task-modulated functional connectivity profiles for individuals and control populations can be reliably discriminated with sufficient imaging time.
• rsFC analysis can differentiate individuals from control groups with adequate data acquisition.