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PET scans, or Positron Emission Tomography scans, are a neuroimaging technique that uses radioactive tracers to measure brain activity. It shows the metabolic processes happening in the brain by detecting levels of glucose uptake.
fMRI (functional Magnetic Resonance Imaging) is another neuroimaging technique that measures changes in blood flow to determine brain activity.
EEG (Electroencephalogram) is a non-invasive technique that records electrical activity generated by neurons using electrodes placed on the scalp.
CT (Computed Tomography) scans use X-rays to create detailed cross-sectional images of the body or brain.