Abstract: A method of identifying chronic pain in a patient including using functional magnetic resonance imaging (fMRI), performing a functional brain scan in the NAc (nucleus accumbens) of a patient brain including extracting activity from the NAc. Database information, which includes fMRI data obtained from healthy patients, may be compared to the extracted activity to determine if patient is a chronic pain patient. In patients with chronic pain, the method may be repeated to evaluate the effects of the treatment. A resting state brain scan may be performed initially, and a Fourier transform may be performed to obtain frequency content. The frequency bands of the method may be broken down to extract information in a 0.01-0.027 Hz frequency band.