Inclusion criteria:

1. patient must be >/= 18 years of age;
2. patients who will undergo neurosurgical resection of brain tumors;
3. patients who will undergo presurgical fMRI as standard of care;
4. patients who on neurosurgical evaluation will undergo direct cortical stimulation (DCS) as standard of care.

For the retrospective study, we will review up to 1600 patients all clinical presurgical fMRI studies performed on brain tumor patients at the MD Anderson since 5/2004.

The inclusion criteria:

1. patients must be >/= 18 years of age;
2. patients who had the presurgical fMRI that contained at least one task-based fMRI scan.

Exclusion Criteria:

Exclusion criteria for the prospective study:

1. patients cannot give informed consent;
2. patients cannot undergo MRI examinations;
3. patients who are indicated for speech fMRI only but cannot comply with any of the speech tasks based on the evaluation of a clinical neuropsychologist.

Exclusion criteria for the retrospective study:

1. all fMRI scans were contaminated by head motions (translation > 2 mm or rotation > 2 degrees);
2. only speech fMRI paradigms were performed, and patients were not able to comply with any of the speech tasks based on the evaluation of a clinical neuropsychologist.