A Positron Emission Tomography (PET) scan is an imaging test that shows how our tissues and organs are functioning. In order to show the activity of the organ or tissue studied, a tracer has to be administered to the patient. This tracer collects to the areas of the body that have higher levels of chemical activity, probably our areas of interest. A PET scan of a person smelling a flower would show higher activity in the brain area responsible for processing and identifying smells. In the human brain, this is the olfactory bulb, a neural structure of the forebrain. Higher activity would also be detected in the thalamus, a region that receives incoming sensory information. On the other hand, a PET scan of a person speaking would show higher activity in the Broca area and the temporal lobe. The temporal lobe is involved in memory and speech. Broca area is a region in the frontal lobe which is responsible for speech production and language processing.
