. ▁It ▁has ▁F DA ▁appro val ▁for ▁treatment ▁of ▁de pression . ▁It ▁is ▁also ▁being ▁research ed ▁for ▁other ▁applications ▁such ▁as ▁aut ism . ▁One ▁issue ▁is ▁that ▁no ▁two ▁bra ins ▁are ▁al ike ▁and ▁stim ulation ▁can ▁cause ▁either ▁polar ization ▁or ▁dep olar ization . ▁( et ▁al .), ▁Mar ino ▁( et ▁al .), ▁and ▁others . ▁ ▁How ▁these ▁help ▁study ▁the ▁brain ▁Mag net ic ▁reson ance ▁imag ing ▁is ▁a ▁vital ▁tool ▁in ▁ne uro log ical ▁research ▁in ▁showing ▁activation ▁in ▁the ▁brain ▁as ▁well ▁as ▁providing ▁a ▁compreh ensive ▁image ▁of ▁the ▁brain ▁being ▁studied . ▁While ▁MR Is ▁are ▁used ▁clin ically ▁for ▁showing ▁brain ▁size , ▁it ▁still ▁has ▁relev ance ▁in ▁the ▁study ▁of ▁bra ins ▁because ▁it ▁can ▁be ▁used ▁to ▁determine ▁extent ▁of ▁inj uries ▁or ▁de formation . ▁These ▁can ▁have ▁a ▁significant ▁effect ▁on ▁person ality , ▁sense ▁per ception , ▁memory , ▁higher ▁order ▁thinking , ▁movement , ▁and ▁spatial ▁understanding . ▁However , ▁current ▁research ▁tends ▁to ▁focus ▁more ▁so ▁on ▁f M RI ▁or ▁real - time ▁functional ▁M RI ▁( rt f M RI ). ▁These ▁two ▁methods ▁allow ▁the ▁scient ist ▁or ▁the ▁particip ant , ▁respectively , ▁to ▁view ▁activation ▁in ▁the ▁brain . ▁This ▁is ▁incred ibly ▁vital ▁in ▁understanding ▁how ▁a ▁person ▁thinks ▁and ▁how ▁their ▁brain ▁react s ▁to ▁a ▁person ' s ▁environment , ▁as ▁well ▁as ▁understanding ▁how ▁the ▁brain ▁works ▁under ▁various