▁or ▁previously ▁learned ▁facts ▁( exp licit ▁memory ) ▁become ▁in access ible ▁or ▁lost . ▁Am nes ia ▁can ▁result ▁from ▁a ▁number ▁of ▁different ▁causes , ▁including ▁en ce phal itis , ▁severe ▁tra um atic ▁brain ▁injury , ▁vit amin ▁B 1 ▁def ic iency ▁as ▁seen ▁in ▁K ors ak off ' s ▁Sy nd rome , ▁and ▁psych otic ▁episodes , ▁or ▁by ▁witness ing ▁an ▁em otion ally ▁tra um atic ▁event ▁( Dis soci ative ▁am nes ia ). ▁D ys function ▁of ▁the ▁temporal ▁and ▁front al ▁lo bes ▁have ▁been ▁observed ▁in ▁many ▁cases ▁of ▁foc al ▁retro grade ▁am nes ia , ▁whether ▁met abol ic ▁or ▁the ▁result ▁of ▁les ions . ▁However , ▁this ▁evidence ▁only ▁appears ▁to ▁correlate ▁with ▁the ▁sympt oms ▁of ▁retro grade ▁am nes ia ▁as ▁cases ▁have ▁been ▁observed ▁where ▁patients ▁suffering ▁from ▁minor ▁conc uss ions , ▁showing ▁no ▁visible ▁brain ▁damage , ▁develop ▁F RA . ▁It ▁has ▁been ▁suggested ▁that ▁F RA ▁could ▁represent ▁a ▁variety ▁of ▁different ▁dis orders , ▁cogn itive ▁def ic its , ▁or ▁conditions ▁that ▁result ▁in ▁dis pro port ion ate ▁loss ▁of ▁explicit ▁memory , ▁hence ▁Dis pro port ion ate ▁Ret ro grade ▁Am nes ia . ▁ ▁The ▁Face ▁Adv antage ▁The ▁Face ▁Adv antage ▁allows ▁information ▁and ▁mem ories ▁to ▁be ▁re called ▁easier ▁through ▁the ▁presentation ▁of ▁a ▁person ' s ▁face ▁rather ▁than ▁a ▁person ' s ▁voice . ▁F aces