System and method for functional brain organization mapping

1. A method for producing a functional brain map of a subject, the method comprising:

i. providing a set of time-series functional magnetic resonance image (fMRI) data acquired from a subject;

ii. providing a population atlas that associates locations in a population brain to a plurality of functional connectivity networks, the population brain representing a population of subjects;

iii. providing a variation map indicative of inter-subject variability in the population atlas;

iv. initializing a subject map using the population atlas, the subject map defining a plurality of functional connectivity networks and indicating locations in a brain of the subject that are assigned to the plurality of functional connectivity networks;

v. determining a reference signal for each functional connectivity network in the subject map using time-series signals derived from the set of time-series fMRI data;

vi. computing a plurality of correlation values between the time-series signals derived from the set of time-series fMRI data and each reference signal determined in step (v);

vii. updating the subject map by reassigning locations in the subject brain based on the computed correlation values;

viii. updating the reference signal for each functional connectivity network using the updated subject map, the population atlas, the variation map, and the set of fMRI data;

ix. iteratively repeating steps (vi), (vii) and (viii) until a stopping criterion is satisfied; and

x. generating a report indicative of a functional brain organization for the brain of the subject using the subject map.

2. The method of claim 1 , wherein the method further comprises acquiring the set of time-series fMRI data using a magnetic resonance imaging (MRI) system.

3. The method of claim 1 , wherein initializing the subject map comprises projecting the population map onto a model of the subject's brain surface.

4. The method of claim 1 , wherein the time-series signals are associated with locations in the brain of the subject.

5. The method of claim 1 , wherein determining the reference signal at step (v) comprises averaging the time-series signals from locations assigned to the same functional connectivity network.

6. The method of claim 1 , further comprising computing a confidence value defined by a ratio between a first correlation value and a second correlation value, and wherein reassigning the locations at step (vii) is performed in accordance with the confidence value being above a threshold.

7. The method of claim 1 , wherein updating the reference signal at step (viii) comprises computing a sum of the reference signal at step (v) and a weighted reference signal determined in dependence of the variation map, a signal-to-noise ratio of the time-series signals, and an iteration number.

8. The method of claim 1 , wherein the provided set of time-series fMRI data is indicative of a resting state of the subject.

9. The method of claim 1 , wherein the provided set of time-series fMRI data is indicative of a functional task performed by the subject while the time-series fMRI data was acquired.

10. A system for producing functional brain mapping of a subject, the system comprising:

an input configured to:

receive a set of time-series functional connectivity magnetic resonance image (fMRI) data acquired from a subject;

receive a population atlas that associates locations in a population brain to a plurality of functional connectivity networks, the population brain representing a population of subjects;

receive a variation map indicative of inter-subject variability in the population atlas;

at least one processor in communication with the input and configured to:

a. initialize a subject map using the population atlas, the subject map defining a plurality of functional connectivity networks and indicating locations in a brain of the subject that are assigned to the plurality of functional connectivity networks;

b. determine a reference signal for each functional connectivity network in the subject map using time-series signals derived from the set of time-series fcMRI data;

c. compute a plurality of correlation values between the time-series signals derived from the set of time-series fMRI data and each determined reference signal;

d. update the subject map by reassigning locations in the subject brain based on the computed correlation values;

e. update the reference signal for each functional connectivity network using the updated subject map, the population atlas, the variation map, and the set of fMRI data;

f. iteratively repeat steps (c), (d) and (e) until a stopping criterion is satisfied;

g. generate a report indicative of a functional brain organization for the brain of the subject using the subject map; and

an output configured for displaying the report.

11. The system of claim 10 , wherein initializing the subject connectivity map comprises projecting the population map onto a model of the subject's brain surface.

12. The system of claim 10 , wherein the time-series signals are associated with locations in the brain of the subject.

13. The system of claim 10 , wherein determining the reference signal at step (b) comprises averaging the time-series signals from locations assigned to the same functional connectivity network.

14. The system of claim 10 , the at least one processor is further configured to compute a confidence value defined by a ratio between a first correlation value and a second correlation value, and wherein the at least one processor is configured to reassign the locations in the subject brain in accordance with the confidence value being above a threshold.

15. The system of claim 10 , wherein the at least one processor is further configured to compute at step (e) a sum of the reference signal from step (b) and a weighted reference signal determined in dependence of the variation map, a signal-to-noise ratio of the time-series signals, and an iteration number.

16. The system of claim 10 , wherein received set of time-series fMRI data is indicative of at least one of a resting state of the subject and a functional task performed by the subject while the time-series fMRI data was acquired.

17. A magnetic resonance imaging (MRI) system for producing functional brain mapping of a subject, the system comprising:

a magnet system configured to generate a polarizing magnetic field about at least a portion of a subject arranged in the MRI system;

a plurality of gradient coils configured to apply a gradient field to the polarizing magnetic field;

a radio frequency (RF) system configured to apply a RF excitation field to a brain of the subject, and acquire therefrom a set of time-series functional connectivity magnetic resonance image (fMRI) data;

at least one computer configured to:

a. receive a population atlas that associates locations in a population brain to a plurality of functional connectivity networks, the population brain representing a population of subjects;

b. receive a variation map indicative of inter-subject variability in the population atlas;

c. initialize a subject map using the population atlas, the subject map defining a plurality of functional connectivity networks and indicating locations in a brain of the subject that are assigned to the plurality of functional connectivity networks;

d. determine a reference signal for each functional connectivity network in the subject map using time-series signals derived from the set of time-series fcMRI data;

e. compute a plurality of correlation values between the time-series signals derived from the set of time-series fMRI data and each determined reference signal;

f. update the subject map by reassigning locations in the subject brain based on the computed correlation values;

g. update the reference signal for each functional connectivity network using the updated subject map, the population atlas, the variation map, and the set of fMRI data;

h. iteratively repeat steps (e), (f) and (g) until a stopping criterion is satisfied; and

i. generate a report indicative of a functional brain organization for the brain of the subject using the subject map.

18. The MRI system of claim 17 , wherein initializing the subject connectivity map comprises projecting the population map onto the subject map.

19. The MRI system of claim 17 , wherein the time-series signals are associated with locations in the brain of the subject.

20. The MRI system of claim 17 , wherein determining the reference signal at step (b) comprises averaging the time-series signals from locations assigned to the same functional connectivity network.

21. The MRI system of claim 17 , the at least one computer is further configured to compute a confidence value defined by a ratio between a first correlation value and a second correlation value and wherein the computer system is configured to reassign the locations in the subject map in accordance with the confidence value being above a threshold.

22. The MRI system of claim 17 , wherein the at least one processor is further configured to compute at step (g) a sum of the reference signal from step (d) and a weighted reference signal determined in dependence of the variation map, a signal-to-noise ratio of the time-series signals, and an iteration number.

23. The MRI system of claim 17 , wherein received set of time-series fMRI data is indicative of at least one of a resting state of the subject and a functional task performed by the subject while the time-series fMRI data was acquired.