According to the focus on neuroscience box in the text, the is the most invasive of the brain imaging techniques that can be used in psychological research.

PET scan

Explanation:

According to the Focus on Neuroscience box in the text, the PET scan is the MOST invasive of the brain imaging techniques that can be used in psychological research.

A positron emission tomography (PET) scan is an imaging test that allows your doctor to check for diseases in your body. The scan uses a special dye containing radioactive tracers. PET scan can be used to see how the brain is functioning.

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