Thanks Megaspaz!) Like the left turn this is another hand signal that you should know if you have your license. Unlike the left hand turn this one is a little more tricky to figure out if you aren't familiar with it so don't expect your average car driver to know what this means.
A Single Photon Emission Computed Tomography (SPECT) scan is a type of nuclear imaging test that shows how blood flows to tissues and organs. A SPECT scan integrates two technologies to view your body: computed tomography (CT) and a radioactive material (tracer). The tracer is what allows doctors to see how blood flows to tissues and organs.
Single Photon Emission Computed Tomography (SPECT) can be used to look for areas of the brain with altered metabolism, cerebral blood flow, or neurotransmitter function. The idea is that these areas of altered activity are more likely to be areas producing seizures in a given patient.