Answer:
Positron emission tomography (PET)
Step-by-step explanation:
Positron emission tomography (PET) consists of the measurement of the physiological function by inspecting the flow of the blood, metabolic functions, radiolabelled drugs, and neurotransmitters. PET provides quantitative analyses making it possible to monitor relative changes as time passes, keeping control of the progress of a disease or how the person reacts to a stimulus. To do it, the person receives a low quantity of a radioactive tracer into his/her organism via injection.