▁conscious ▁aw aren ess . ▁For ▁instance , ▁when ▁walking ▁towards ▁an ▁object ▁on ▁the ▁ground ▁to ▁grab ▁it , ▁the ▁brain ▁is ▁running ▁off line ▁motor ▁plans ▁to ▁determine ▁the ▁optimal ▁hand ▁position ing ▁and ▁g rip ▁strength ▁to ▁pick ▁up ▁the ▁object . ▁ ▁Visual ▁system ▁ ▁Visual ▁modal ▁specific ▁em ul ators ▁have ▁been ▁experiment ally ▁shown ▁to ▁exist ▁in ▁an ▁experiment ▁by ▁Ernst ▁Mach ▁in ▁ 1 8 9 6 . ▁In ▁his ▁experiment , ▁the ▁subjects ’ ▁eyes ▁were ▁prevent ed ▁from ▁moving ▁and ▁then ▁they ▁were ▁exposed ▁to ▁a ▁stim ulus ▁that ▁would ▁trigger ▁a ▁sac cade . ▁Most ▁subjects ▁reported ▁experien cing ▁their ▁entire ▁visual ▁scene ▁briefly ▁being ▁shift ▁in ▁the ▁opposite ▁direction ▁of ▁the ▁stim ulus . ▁Mach ▁thus ▁infer red ▁that ▁there ▁is ▁a ▁mechanism ▁within ▁the ▁visual ▁system ▁producing ▁an ▁a ▁pri ori ▁estimate ▁of ▁future ▁visual ▁scenes ▁based ▁upon ▁motor ▁commands ▁and ▁current ▁visual ▁stim uli . ▁In ▁a ▁similar ▁experiment ▁on ▁mon keys , ▁this ▁particular ▁emulator ▁was ▁found ▁to ▁exist ▁within ▁a ▁group ▁of ▁neur ons ▁within ▁par iet al ▁cor tex . ▁Furthermore , ▁it ▁was ▁discovered ▁that ▁these ▁neur ons ▁began ▁firing ▁before ▁the ▁eye ▁even ▁moved . ▁They ▁only ▁fired , ▁however , ▁if ▁the ▁motor ▁command ▁would ▁result ▁in ▁a ▁visual ▁sac cade . ▁This ▁suggests ▁that ▁visual ▁em ul ators ▁are ▁mod ally ▁specific . ▁ ▁App lications ▁for ▁em ul ators ▁ ▁Em ul ators ▁can ▁be ▁useful ▁in ▁a ▁variety ▁of ▁indust ries