Hockenbury Discovering Psychology 5th txtbk

266 CHAPTER 6 MemoryIn general, Henry was unable to acquire new long-term memories of events(episodic information) or general knowledge (semantic information). Still, every nowand then, Henry surprised his doctors and visitors with some bit of knowledge thathe acquired after the surgery (see the In Focus box “H.M. and Famous People”).Henry’s case suggests that the hippocampus is not involved in most short-termmemory tasks, nor is it the storage site for already established long-term memories.Instead, the critical role played by the hippocampus seems to be the encoding of newmemories for events and information and the transfer of those new memories fromshort-term to long-term memory.Implicit and Explicit Memory in Anterograde Amnesia Henry’s case and thoseof other patients with anterograde amnesia have contributed greatly to our understandingof implicit versus explicit memories. To refresh your memory, implicitmemories are memories without conscious awareness. In contrast, explicit memoriesare memories with conscious awareness.Henry could not form new episodic or semantic memories, which reflects theexplicit memory system. But he could form new procedural memories, whichreflects the implicit memory system. For example, when given the same logical puzzleto solve several days in a row, Henry was able to solve it more quickly each day.This improvement showed that he implicitly “remembered” the procedure involvedIN FOCUSH.M. and Famous PeopleWhen his hippocampus was removed, Henry Molaison lost theability to quickly encode new semantic and episodic memories.For example, he was unable to learn new vocabulary words orremember people he had met. But is the hippocampus necessaryfor all semantic learning? Or is it possible that other brain areasmight support some limited learning of new knowledge?To test this idea, psychologists Gail O’Kane, ElizabethKensinger, and Suzanne Corkin (2004) evaluated Henry for hisknowledge of people who became famous after his surgery in1953. On the first day, Henry was given the famous person’s firstname as a cue and asked to say the last name that came to hismind. Examples were “Elvis_____ (Presley)” and “Fidel _____(Castro),” who first became famous during the 1950s; “Lyndon_____ (Johnson)” and “Ray _____ (Charles)” from the 1960s;“Sophia _____ (Loren)” from the 1970s; and “Ronald _____(Reagan)” from the 1980s. Henry was able to correctly supplythe last name of 12 out of 35 famous people including MartinLuther King, Sophia Loren, and Ronald Reagan.In a second test on the next day, Henry was able to generatethe last names for an additional11 famous people after being givenbackground information about them.For example, provided with thedetails “famous artist, born in Spain,formulated Cubism, works includeGuernica,” Henry responded “Picasso”to the cue “first name is Pablo.”Henry’s ability to generate the lastnames of well-known people indicatedthat he had acquired some declarativesemantic knowledge. O’Kane and hercolleagues (2004) wondered whether Henry could go beyond thissuperficial knowledge and provide specific details. In a differenttest, Henry was able to provide two or more pieces of informationabout 12 people who had become prominent after theonset of his amnesia.For example, after correctly identifying John F. Kennedy as a famousperson, Henry indicated that Kennedy was Catholic, hadbecome president, that somebody shot him, and that he didn’tsurvive. Henry was also able to provide details about John Glenn,Ray Charles, Woody Allen, Liza Minnelli, and Sophia Loren.According to O’Kane and her colleagues (2004), “These resultsprovide robust, unambiguous evidence that at least some semanticlearning can be supported by structures beyond thehippocampus.” However, the limitations of Henry’s semanticlearning must also be stressed. Henry was still unable to quicklyacquire new semantic or episodic memories. It was only afteryears of extended repetitions of information that Henry acquiredsome limited bits and pieces of new knowledge about a fewfamous people.