In addition to alterations in brain structure, recent findings have suggested decrements in brain functioning associated with adolescent substance use. Functional magnetic resonance imaging (fMRI) investigates neural activity of the brain by measuring changes in blood oxygen level dependent (BOLD) signal 50, which indicates areas of increased activation in response to a mental task or stimulus 51. This technique is noninvasive and does not require injections or radioactive materials, making it a safe and appropriate technique for examining adolescent brain functioning.
