This chapter is intended for investigators of schizotypy who contemplate incorporation of physiological neuroimaging methods, or who wish to have a better appreciation of the potential and limitations of such methods. Isotopic techniques for imaging neurophysiology make use of the fact that active neurons have metabolic needs for oxygen and glucose, and that cerebral blood flow rates change in response to these needs. Such measures can help identify regions of abnormal physiological activity associated with behavioral deficits. These isotopic techniques for measuring cerebral metabolism and blood flow can be traced to the pioneering method of Kety and Schmidt for measuring whole-brain metabolism and blood flow. Positron emission tomography (PET) has made it possible to measure in vivo biochemical and physiological processes in the human brain. Neuropsychological batteries can be distinguished from standard psychological tests in that they can provide links between a profile of behavioral measures and brain topography.