This invention involves blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) using external stimuli. Different colors of light can be used as the stimulus to assess differential BOLD response to diagnose neurological disorders (e.g., Parkinson's disease, attention deficit disorder, schizophrenia, and substance abuse). In addition, very low dose administration of a drug that affects intracerebral vasculature can enhance BOLD response, facilitating detection and improving diagnostic capabilities. Using a very low dose of d-amphetamine, BOLD response to blue light is increased.
Magnetic resonance with stimulation