The district court’s decision is affirmed for the following reasons. First, the ALJ was not required to obtain testimony from a medical advisor regarding Brown’s childhood disability claim. See Richardson v. Perales, 402 U.S. 389, 390, 91 S.Ct. 1420, 28 L.Ed.2d 842 (1971). Second, the ALJ;s residual functional capacity assessment is supported by substantial evidence. The ALJ’s finding that Brown was able to perform medium work implied that Brown could also perform less demanding sedentary work. Also, Brown was able to attend college, sit in classes, and maintain a 19 hour course-load. Finally, the ALJ did not err in using the guidelines to assess Brown’s ability to work. Brown does not allege that she suffers from any other nonexertional limitations besides pain stemming from her interstitial cystitis, and Brown’s extensive activities support the ALJ’s finding that her pain did not significantly limit her ability to work. AFFIRMED.