following: pregnancy, serious medical or neurological illness, systolic blood pressure >140 mmHG, diastolic blood pressure <90 mmHG, any current major axis I psychiatric diagnosis (except alcohol and nicotine use disorder), metal implants or paramagnetic objects, employment as a radiation worker or exposure to radiation that exceeds annual dose of radiation, medical history of chronic obstructive pulmonary disease or other chronic respiratory disorders, and renal or liver problems.
