▁is ▁a ▁large ▁improvement ▁to ▁single ▁cell ▁or ▁lo ci ▁activation ▁by ▁means ▁of ▁expos ing ▁the ▁brain ▁and ▁contact ▁stim ulation . ▁Function al ▁M RI ▁allows ▁research ers ▁to ▁draw ▁associ ative ▁relationships ▁between ▁different ▁lo ci ▁and ▁regions ▁of ▁the ▁brain ▁and ▁provides ▁a ▁large ▁amount ▁of ▁knowledge ▁in ▁establish ing ▁new ▁land marks ▁and ▁lo ci ▁in ▁the ▁brain . ▁ ▁Comput ed ▁tom ography ▁( CT ) ▁is ▁another ▁technology ▁used ▁for ▁sc anning ▁the ▁brain . ▁It ▁has ▁been ▁used ▁since ▁the ▁ 1 9 7 0 s ▁and ▁is ▁another ▁tool ▁used ▁by ▁neu ros cient ists ▁to ▁track ▁brain ▁structure ▁and ▁activation . ▁While ▁many ▁of ▁the ▁functions ▁of ▁CT ▁sc ans ▁are ▁now ▁done ▁using ▁M RI , ▁CT ▁can ▁still ▁be ▁used ▁as ▁the ▁mode ▁by ▁which ▁brain ▁activation ▁and ▁brain ▁injury ▁are ▁detected . ▁Using ▁an ▁X - ray , ▁research ers ▁can ▁detect ▁radio active ▁markers ▁in ▁the ▁brain ▁that ▁indicate ▁brain ▁activation ▁as ▁a ▁tool ▁to ▁establish ▁relationships ▁in ▁the ▁brain ▁as ▁well ▁as ▁detect ▁many ▁inj uries / d ise ases ▁that ▁can ▁cause ▁last ing ▁damage ▁to ▁the ▁brain ▁such ▁as ▁an eur ys ms , ▁deg ener ation , ▁and ▁cancer . ▁ ▁Pos it ron ▁emission ▁tom ography ▁( P ET ) ▁is ▁another ▁imag ing ▁technology ▁that ▁a ids ▁research ers . ▁Instead ▁of ▁using ▁magnetic ▁reson ance ▁or ▁X - ray s , ▁P ET ▁sc ans ▁rely ▁on ▁posit ron ▁em itting ▁markers