▁cor tex ▁contr al ater al ▁to ▁the ▁al ien ▁hand , ▁while ▁volunt ary ▁movements ▁of ▁the ▁same ▁body ▁part ▁included ▁the ▁natural ▁activation ▁of ▁motor ▁association ▁cor tex ▁associated ▁with ▁the ▁prem ot or ▁process . ▁The ▁clin ical ▁definition ▁requires ▁" fe eling ▁that ▁one ▁lim b ▁is ▁foreign ▁or ▁has ▁a ▁will ▁of ▁its ▁own , ▁together ▁with ▁observable ▁invol unt ary ▁motor ▁activity " ▁( emph asis ▁in ▁original ). ▁This ▁synd rome ▁is ▁often ▁a ▁result ▁of ▁damage ▁to ▁the ▁cor pus ▁call os um , ▁either ▁when ▁it ▁is ▁sever ed ▁to ▁treat ▁int ract able ▁ep ile ps y ▁or ▁due ▁to ▁a ▁stroke . ▁The ▁standard ▁ne uro log ical ▁explanation ▁is ▁that ▁the ▁felt ▁will ▁reported ▁by ▁the ▁speaking ▁left ▁hem is phere ▁does ▁not ▁correspond ▁with ▁the ▁actions ▁performed ▁by ▁the ▁non - spe aking ▁right ▁hem is phere , ▁thus ▁suggesting ▁that ▁the ▁two ▁hem is pher es ▁may ▁have ▁independent ▁sens es ▁of ▁will . ▁ ▁In ▁addition , ▁one ▁of ▁the ▁most ▁important ▁(" first ▁rank ") ▁di agnostic ▁sympt oms ▁of ▁sch iz op hren ia ▁is ▁the ▁patient ' s ▁del usion ▁of ▁being ▁controlled ▁by ▁an ▁external ▁force . ▁People ▁with ▁sch iz op hren ia ▁will ▁sometimes ▁report ▁that , ▁although ▁they ▁are ▁acting ▁in ▁the ▁world , ▁they ▁do ▁not ▁recall ▁initi ating ▁the ▁particular ▁actions ▁they ▁performed . ▁This ▁is ▁sometimes ▁li ken ed ▁to ▁being ▁a ▁robot ▁controlled ▁by ▁someone ▁else .