Mary Katherine Gale1, Maysam Nezafati1, and Shella Keilholz1
1Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, United States
1Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, United States
Sample entropy can be used to assess BOLD signal complexity and predictability in resting-state and task fMRI. Task-relevant brain regions tend to display lower entropy than less relevant regions, and there is a strong negative correlation between BOLD signal amplitude and entropy.
Figure 1: Parcel number vs. entropy z-score for motor task. Task-relevant brain regions are indicated. Note lines at z = +/- 1.96, indicating thresholds for parcels w/ statistical significance.
Figure 3: Parcel power vs. entropy for motor (left; r = -0.685) and emotion (right; r = -0.670) scans. Negative correlation held for all task-state scans, with correlation coefficients ranging from r = -0.670 (emotion task) to r = -0.820 (relational processing task).
