Is this necessary? I heard that some (hidden or silent) forms of seizures could be manifested in the form of anxiety symptoms or sensations due to irregularities in the brain waves. Hence, if the MRI or EEG tests detect abnormalities in the brain, it could be the root cause of one's anxiety, and hence, the cause is not psychologically or emotionally induced. 

My psychiatrist suggested that I take this range of tests to systematically rule out other biological causes of severe anxiety as I'm puzzled why did I suffer from debilitating extreme anxiety out of the blue?