Memory & Cognition1979, 7 (3), 232·239

Effects of encoding instructions and retrievalcuing on recall in Korsakoff patients

JOHN MeDOWALLPorirua Hospital, Porirua, New Zealand,

and Victoria University 0/ Wellington, New Zealand

The relationship between the depth of encoding a word and its subsequent recall, eithereued or noneued, was investigated in this study. In Experiment 1, Korsakoff subjects andaleoholie eontrols were shown a categorized word list under one of three different encodinginstruetions: (1) nonsemantie, that is, detecting the presenee or absence of the letter He" ineaeh word, (2) semantic, that is, assigning words to their eorrect taxonomie eategory, and (3) noencoding instruetions. Semantie encoding instruetions resulted in higher reeall for both diag­nostie groups than the other instruetions. In Experiment 2, subjects were again assigned toone of the three encoding instruetions as in Experiment 1, but all groups received cues (eategorylabels) at the time of reeall. Cuing inereased reeall for all but the group receiving instruc­tions to encode nonsemantical1y. Experiment 3 was a replication of the previous experiments.The results indicated that Korsakoff subjects were capable of encoding semantically withoutspecific instructions to do so but were impaired in the ability to generate retrieval cues atthe time of recall.

The clinical symptoms of Korsakoffs syndrome havebeen carefully described by a number of authors (seeTalland, 1965; Victor & Yakovlev, 1955, for reviews).While there is considerable variation in the nature of theillness between individuals, it is generally agreed that ittakes the following course: The patient is admitted to ahospital showing signs of acute confusion and agitation.Typically, he is disoriented in time and place and maydisplay evidence of ataxia and extraocular movements.A history of severe alcohol abuse is usually noted.The acute confusional state may last for several daysor weeks, after which the patient usually becomescorrectly oriented and, in general, is able to perceive hissurroundings correctly. He can understand sentencesand can usually engage in rational conversation.

Closer examination of the patient at this time revealsa profound amnesia in which the memory for recentevents is severely impaired. The patient can typicallyrecall events from the remote past correctly, but insome cases these are recalled out of their correcttemporal sequence. Immediate memory, as measured bydigit span tests, is not impaired (Talland, 1959; Victor,Herman, & White, 1959), and the IQ usually remains

The author would like to thank the We1lington HospitalBoard for the use of their facilities during the preparation ofthis manuscript. The valuable encouragement and assistance ofMurray 1. White, K. G. White, and S. Niemiec is gratefullyacknowledged. Requests for reprints should be sent tolohn McDowall, Psychology Department, Porirua Hospital,Private Bag, Porirua, New Zealand.

within the normal range. In addition to aretrogradeamnesia, the ability to acquire new information isseverely impaired (anterograde amnesia). The patientis often unable to recall the name of the hospital orward he resides in and appears unable to learn the namesof the staff with whom he regularly deals.

While a great deal of clinical and anecdotal evidenceexists on the nature of the memory deficit (see Meissner,1968; Talland, 1965, for reviews), it has only recentlybeen investigated through the use of informationprocessing techniques. Most emphasis has been placedon the nature of the anterograde amnesia, and differentworkers have debated as to whether it is due toimperfect initial encoding, impaired retrieval abilities,or a combination of these and other factors.

In current memory research, there is considerableevidence to suggest that stimuli may be encoded indifferent ways within the memory system. A word maybe encoded in terms of its physical features (e.g., as towhether or not it contains the letter "m"), or it maybe encoded in terms of its phonemic features (e.g., asto whether it rhymes with the word "cat"). A word mayalso be encoded semantically, that is, in terms of itsmeaning (e.g., as to whether the word refers to a type ofanimal). Cermak (1972), Craik and Lockhart (1972),and Craik and Tulving (1975) have hypothesized thatthe persistence of the memory trace is a function of thedepth of analysis performed on the stimuli with deeper(semantic) levels of encoding being associated withlonger lasting memory traces (and thus higher recallperformances), as compared with nonsemantic levels ofencoding that result in rapidly decaying memory traces.

Copyright 1979 Psychonomic Society, Inc. 232 0090-502X/79/030232-08$Ol.05/0

ENCODING AND RETRlEVALIN KORSAKOFF PATIENTS 233

There is now a considerable body of evidence thatshows that, normally, semantic encoding results inhigher performance levels than physical or phonemicencoding for both recall and recognition tasks (Craik &Tulving, 1975; Fisher & Craik, 1977; Hyde, 1973;Hyde & Jenkins, 1973; Till & Jenkins, 1973).

Cermak and Butters (1973) hypothesized thatKorsakoff patients suffer from a basic impairment inthe ability to encode stimuli, particularly along semanticdimensions, relying rather on physical and phonemiclevels of encoding. The initial evidence for this view wasprovided by Cermak and Butters (1972), who hadKorsakoff subjects listen to a list of eight wordscontaining two words from each of four taxonomiecategories. The subjects were asked to recall the wordsin any order (free recall). A second list of eight wordsbelonging to the same four categories was administeredto the same subjects, who were then told the categorynames before the list presentation and were alsoinformed that they would be required to recall thewords category by category as directed by the examiner(cued recall). Words were presented orally at a rate ofI word/sec. Korsakoff subjects recalled significantlyfewer words under the cued condition than under thefree condition, whereas a control group of alcoholicsshowed improved recall under the cued condition.The authors concluded that, since the Korsakoff subjectsdid not benefit from the provision of semantic cues(category labels), they were not employing semantieencoding strategies but were probably relying onauditoryencoding.

There are two main problerns with the conclusionsof this study. First, the design of the experiment mayhave inadvertently maximized proactive interference(PI), in that List 2 consisted of words taken from thesame taxonomie categories as those used in List I.The poor performance of the Korsakoff subjects onList 2 may have reflected an excessive susceptibilityto PI. This effect has been confirmed in a number ofindependent experiments (Warrington & Weiskrantz,1970, 1974). Second, there is evidence indicating thatKorsakoff subjects are impaired in the rate at whiehthey can encode information. Oscar-Berman, Goodglass,and Cherlow (1973) used a visual backward maskingparadigm to examine information processing times inKorsakoff subjects and non-Korsakoff controls andfound that Korsakoff subjects had abnormally highvisual processing times. The l-word/sec presentationrate used in the Cermak and Butters (1972) study mayhave been inadequate to allow semantic encoding.Providing category cues may have interfered with roterecall,

Cermak, Butters, and Gerrein (1973) carried outfour experiments to investigate further the semanticencoding ability of Korsakoff subjects. One experi­ment was an attempt to reconcile the findings of Cermak

and Butters (1972) that Korsakoffs were unable tobenefit from category cuing with those of an earlierexperiment by Warrington and Weiskrantz (1971), whofound that category cuing increased recall comparedwith a noncued condition. The results of this experi­ment showed that, while providing category labelsat presentation and recall time did not facilitateimmediate recall, it did facilitate retention after a I-mindelay. The authors did not attempt an explanation ofthis interaction, but they did conclude that Korsakoffsubjects were capable of encoding words by theirsemantic properties "to some extent" (Cermak et al.,1973, p. 87). A second experiment involved reading alist of words to subjects and then providing cues forthe recall of certain words within the list. The cuesused were either acoustic (i.e., a rhyme of the to-be­remembered word) or semantie (i.e., the category nameof which the to-be-remembered word was a member).The rationale for this design was provided earlier byBregman (1968), who showed that semantic cuing wasof value only if the stimuli had been encoded at thislevel. If the subjects had only encoded stimuli at anacoustic level, then only acoustic cuing should aidrecall. In the second experiment, the effects of bothacoustic and semantic cues were assessed by readingsubjects a list of words and then providing a cue to aword that had appeared in the list one, two, three, orsix items prior to the cue item. Before each list presen­tation, subjects were informed as to which type of cuewould be provided. A group of alcoholic patients servedas a control group. The authors concluded that "exceptfor this slightly faster rate of decay in the effectivenessof the category cues, the Korsakoff and alcoholicpatients benefited equally from both acoustic andsemantic cues" (Cermak et al., 1973, p. 88).

An examination of the results of this experimentraises doubts as to the validity of this conclusion and,in a review article (Cermak & Butters, 1973), a modifi­cation of the earlier interpretation is presented. Thus,"the rhyming and category cues were equally effectivein both groups when the to-be-recalled item and its cuewere separated by only one or two intervening items,but with longer delays (three or six items between testitem and cue) between presentation and eued reeall theeategory eue was more effeetive among the eontrols....The sharp decline in the facilitative effects of the cate­gory cue in the Korsakoff patients seemed to indieatea deficiency in the original semantie encoding of the to­be-recalled words" (Cermak & Butters, 1973, p.1121).

Unfortunately, this modified conclusion is also atodds with the original finding, in which the analysis ofvariance indieated that the Korsakoff patients reealledsignifieantly fewer items than the eontrols only after athree-item delay between test item and category cue.In other words, both the Korsakoff patients and thecontrols recalled equally effectively after one, two, and

234 McDOWALL

six intervening items between test item and categorycue, a finding that would be difficult to interpret interms of a semantie encoding deficit.

The third experiment in this study (Cermak et a1.,1973) consisted of presenting subjects with aseries ofwords and measuring recall after providing them withassociative cues (i.e., words that were semantieallyassociated with the to-be-remembered words). Theresults showed that Korsakoff subjects were capable oftaking advantage of such cuing, indicating that theywere encoding words along semantic dimensions. Thiseonclusion was reiterated in a review article by Cermakand Butters (1973), who stated that Korsakoff subjeets"rnay be capable of eneoding semantieally but mayprefer to rely on an acoustic or associative level ofencoding" (p. 1123).

Cermak, Butters, and Moreines (1974) used theWickens (1970) "release from PI" paradigm to exarninethe semantic encoding abilities of Korsakoff subjects.This technique is a modification of the Peterson andPeterson (1959) procedure. Subjects are presentedwith aseries of trials (usually four) in which to-be­remembered words are presented, and the words fallinto a similar class or category (e.g., all animal names).Recall is measured at the end of each trial and istypieally found to decrease over trials due to thehypothesized build-up of PI. On Trial 5, words arepresented from an original class or category, and theamount of PI "release" is measured by the increase inperformance that results from the introduction of thematerial from the new category.

Beginning with the hypothesis that the Korsakoffsubjeets displayed an inability to semantieally encodestimuli, Cermak et a1. (1974) predieted that the amountof PI release shown would vary with the eneodingrequirements of the material presented. Their resultsshowed that when the shift in to-be-rememberedmaterial was of an alphanumerie nature (eonsonanttrigrams presented on the first four trials, shifting toa digit triad on Trial 5), both Korsakoff subjects andeontrols displayed a PI release. But, when the shiftwas of words taken from one taxonomic category onTrials 1-4 to words from a different taxonomie categoryon Trial 5, Korsakoff subjects showed no gain inperformance as opposed to the control group. Theauthors concluded that the Korsakoff patients wereunable to encode the words on the basis of theirsemantic properties and thus gained no benefit from achange in taxonomie category.

While it is possible to view this finding as the resultof a failure to semantieally encode, it eould also beviewed as reflecting a retrieval diffieulty. In other words,Korsakoff subjects may have semantieally eneoded thenew dass of material but failed to gain an inerease inperformance beeause of a failure to generate appropriateretrieval cues. This hypo thesis was investigated by Woodand Kinsbourne (Note 1), who obtained a delayed

release of PI by continuing to provide the new class ofwords on Trials 6 and 7. They argued that the delayedrelease of PI implicated a retrieval failure rather thanan encoding impairment,

Other investigators have also viewed the Korsakoffmemory deficit as a retrieval difficulty. laffe and Katz(1975) exarnined the relative effects of providingcategory label cues at presentation (precuing) and atrecall times (postcuing). This experiment used onlyone subject. Presenting a 25-word list of 5 words fallinginto five taxonomie eategories, laffe and Katz testedthe subject on a free recall test followed by a reeognitiontest. The list was presented under four different cuingeonditions: (1) no cues, (2) posteuing only (i.e., providingthe subject with the category names at recall time),(3) preeuing only (i.e., instructing the subject at thetime of presentation as to the different categoriesinvolved in the word list), and (4) both pre- and post­cuing. The results supported a hypo thesis that involveda deficit in both encoding and retrieval, in that therewas no postcuing advantage unless precues had beenprovided. Precues alone also had no beneficial effect.The results were compatible with the encoding speci­ficity hypothesis (Tulving & Thomson, 1973), whichstates that "specific encoding operations performedon what is perceived determines what is stored and whatis stored determines what retrieval cues are effective inproviding access to what is stored" (p. 369).

In another study that implicates a retrieval difficultyin Korsakoff subjects, Wood and Kinsbourne (Note 1)presented subjects with lists of three words, words ineach list being taken from a single category (e.g., red,blue, green). Three such lists were presented, each beingseparated from the other by 30 sec of digit subtraction.Precued subjects were told the name of the categorylabels at the time of presentation. In the postcuingcondition, subjects were told the category name at thetime of recall and asked to name the words in the list.This study showed that precuing did not benefit recallbut postcuing did. The authors argued that the failureto find any benefit from precuing would not bepredicted from a semantic encoding deficit hypothesis,since an encoding deficit should have been at leastpartly overcome by precuing. This conclusion is onlyvalid, however, if the assumption is made that providingKorsakoff subjects with the appropriate category nameat the time of presentation somehow cues them toprocess the words along semantic dimensions. Thefailure to find any precuing advantage in relation to anon-precued condition may have been due to theinadequacy of the precue to assist semantic encoding.

One of the difficulties with many of the studiesdiscussed above is the ambiguous nature of the encodingstrategy adopted by the subjects during the list presenta­tion. In some cases subjects are given instructions toremember, and the level of encoding is inferred from thenature of the recall. In other studies subjects are

ENCODING AND RETRIEVAL IN KORSAKOFF PATIENTS 235

presented with word lists and cued by category labelsat the time of presentation. The interpretation of therecall performance under this procedure requires theassumption that providing subjects with the appropriatecategory name at presentation time cues subjects toprocess the words along semantic dimensions. There is,however, no independent way of showing that suchsemantic encoding has occurred. What is required isto bring the encoding strategies of the subject underexperimental control. In this way the effects of encodingstrategies on recall and the effects of retrieval cuingunder known encoding strategies can be assessed.

The present experiments bring the encoding strategiesof the subjects under control by varying the instructionsgiven to the subjects prior to the presentation of wordlists. Consider the procedure in which Korsakoff subjectsare presented with the word "cat" and are instructedto place it under its correct superordinate label (i.e.,animal). Correct allocation would require that subjectsencode the words along semantic dimensions. The abilityof subjects to perform this task accurately provides adirect check on whether semantic encoding occurredor not. Similarly, asking subjects to detect the presenceor absence of the letter "e" in each word presentedallows the argument that the word has been encodedalong nonsemantic levels. Experiment 1 used thisprocedure to examine the relative effects of threedifferent encoding instructions on recall: (1) semantic(i.e., allocating words to their correct category labels),(2) nonsemantic (Le., detecting the presence or absenceof the letter "e" in each word), and (3) no instructions(i.e., subjects were asked to remember the words).Experiment 2 examined the effects of the threeencoding instructions in the presence of semantic cuesprovided at recall time. Experiment 3 was a replicationof Experiments 1 and 2.

EXPERIMENT 1

This experiment examined the hypothesis summar­ized by Cermak and Butters (1973) that Korsakoffsubjects are impaired in the ability to encode stimulialong semantic dimensions. There are two related aspectsto this hypothesis. The first is that Korsakoff subjectsare capab1e of encoding stimuli along semantic dimen­sions when given specific instructions to do so. Second,without such instructions, Korsakoff subjects encodestimuli on nonsemantic levels. Experiment 1 comparedthe recall performance of a group of Korsakoff subjectsreceiving no explicit encoding instructions with agroup receiving instructions to encode stimuli alongnonsemantic dimensions and another group engaged ina task designed to maximize semantic encoding. IfKorsakoff subjects typically encode words alongnonsemantic levels in the absence of any explicitencoding instructions, then their recall performanceshould be similar to a group of Korsakoff subjectsinstructed to encode stimuli on a nonsemantic level.

MethodSubjects. Thirty-six male patients were drawn from the

population of a large psychiatrie hospital. The experimentalgroup consisted of 18 subjects diagnosed as Korsakoff patientswith an alcoholic history, The remaining 18 subjects served asa control group and were diagnosed as a1coholic with no knownevidence of brain darnage or memory impairment. Thus, bothgroups had a history of severe alcohol abuse. The mean age ofthe Korsakoff group was 55.33 years (range: 45-66 years),and the mean IQ (Wechsler Adult lntelligence Scale, WAlS,verbal IQ) was 96.38 (range: 89-104). The mean age of thealcoholic group was 55.0 years (range: 39-67 years), and themean IQ was 93.55 (range: 89-108). Korsakoff subjects were notselected if they displayed any evidence of dementia.

Subjects within each of the two diagnostie groups wererandomly assigned to one of three groups, classified aceordingto encoding instruetions: (1) nonsemantic encoding instruetions(NS), (2) semantic eneoding instructions (S), (3) no expliciteneoding instructions (N).

Stimuli and Procedure. Stimulus materials were 2020 x 12.5 cm white cards with one word printed on eaeh card.The 20 words consisted of five nouns from each of fourtaxonomie eategories (kitehen utensils, food, cJothing, andanimals). Subjects were tested individually and sat facing theexperimenter aeross a table upon whieh the eards were presentedone at a time. Subjeets in the NS group were instrueted to detectthe presenee or absence of the letter "e" in each word and toindicate their decision to the experimenter by pointing to oneof two cards on which were printed the words "yes" and "no."All subjeets in this group were told that a recall test was to begiven afterward. Subjeets in Group N were instrueted toremember the stimulus words in preparation for a recall test,Subjeets in Group S were instructed to examine each word asit was presented and to decide to whieh taxonomie categoryit beleng. The four superordinate category names were printedon four eards and were placed on the table in front of thesubject, who was required to point to the appropriate label uponthe presentation of the stimulus. Subjeets in this group werealso told of the recall test that was to follow. Each word waspresented for 4 sec and, at the end of the first presentation,a second presentation was given. At the end of this, subjeetswere given the recall test. Cards were presented in a randomorder with the constraint that no two members of the sametaxonomie category be presented eonsecutively.

Results and DiscussionThe mean percentage correct recall scores for each

of the two diagnostic groups under the three encodinginstructions are shown in Figure 1. The main effect ofdiagnostic group was significant [F(I ,30) = 55.04,p < .001], as was the effect of encoding instruction[F(2,30) = 16.65, P < .001] and the interactionbetween diagnostic group and encoding instruction[F(2,30) = 3.44, p < .05] .

Multiple comparisons of the mean recal1 scores forthe Korsakoff subjects under the three encoding instruc­tions showed differences between NS and S instructions[F(1 ,30) = 16.12, p< .001] and between N and Sinstructions [F(1 ,30) = 8.90, p< .01]. There was nodifference between the means for NS and N instructions[F(1 ,30) = 1.06, p > .05] .

For the alcoholic subjects, there were significantdifferences between the means for NS and S instructions[F(2,30)= 16.13, p<.OOI] and between NS and Ninstructions [F(2,30) = 18.02, p< .001]. There was nodifference between the means for N and S instructions

236 McDOWALL

90 •.....• Alcoholics

•....• Korsakoffs

80

70

~6CJtcl0::

0- 50tcl0::

~40u

~ ae0­z

~211wa..

10

.•.........................•

.."....................

......

............•.......

performance of the group receivmg instructions toencode semantically, if presenting superordinate labelsduring the learning phase provided subjects with directaccess to retrieval cues. In other words, the subjectsreceiving instructions to encode stimuli semanticallywere also direct1y provided with cues that may haveaided them at recall. If Korsakoff subjects in the absenceof explicit encoding instructions do encode stimuli alongsemantic dimensions, then providing category label cuesat the time of recall should facilitate performance. Onthe other hand, if they do not encode semantically inthe absence of explicit instructions to do so, thensemantic cues presented at recall should be relativelyineffectual. Experiment 2 used the same encodinginstructions as in Experiment 1 and provided categorylabel cues at the time of recall.

NS N SEXPERIMENT 2

ENCODING INSTRUCTIONS

Figure 1. Mean percentage correct recall for Korsakoffand alcoholic groups as a function of encoding instrucöons(NS =nonsemantic instructions, N = no instructions, S =semanticinstructions).

(F < 1). Between-group comparisons showed thealcoholic group to have higher recall scores than theKorsakoff group for NS instructions [F(2.30) = 10.32,p< .01], forNinstructions [F(2,30) = 41.29, P < .001],and for S instructions [F(2,30) = 10.32, p< .01] .

The results of this experiment show that whenKorsakoff subjects are given no specific encodinginstructions, their recall performance is the same as thatof a group of Korsakoff subjects instructed to encodewords along nonsemantic levels. In turn, the absence ofspecific encoding instructions results in a lower recallperformance when compared to a group of Korsakoffsubjects instructed to encode stimuli semantically.For the alcoholic group, instructions to encode wordsalong their semantic dimensions resulted in a higherrecall than that obtained by the group instructed toencode nonsemantically. Recal1 performance in theabsence of explicit encoding instructions was equal tothe performance obtained by the group instructed toencode sernantically.

While the results obtained from the Korsakoffsubjects provide support for Cermak and Butters' (1973)theory that Korsakoff subjects do not encode stimulisemantically unless instructed to do so, the findingscould also be viewed as the result of a difficulty inretrieving information. In other words, the Korsakoffsubjects who received no explicit encoding instructionsmay have semantically encoded the words adequatelybut failed to increase their recall scores above that of thegroup receiving instructions to encode nonsemanticallybecause of a failure to generate their own retrievalcues. This argument could explain the higher recall

MethodSubjects, Thirty-six male patients who bad not served as

subjects in Experiment 1 were used in the present experiment.Eighteen subjects were diagnosed as alcoholic Korsakoffpatients, and 18 subjects diagnosed as alcoholic served in thecontrol group. Subjects within each of the two diagnosticgroups were randomly assigned to one of three encodinginstruction groups as in Experiment 1. The mean age of theKorsakoff group was 59.17 years (range: 46-68 years), and themean IQ was 97.66 (range: 90-106). The mean age of thealcoholic group was 55.61 years (range: 40-67 years), and themean IQwas 101.44 (range: 93-110).

Stimuli and Procedure, The stimulus materials and procedurewere identical to those in Experiment 1 except that subjectsin all groups received category label cues at the time of recall.Category labels were printed on cards and, at the time of recall,were placed one at a time in front of the subject, who was askedto recall all the stimulus words presented that belonged to thatcategory.

Resultsand DiscussionThe mean percentage correct recall scores for subjects

in the two diagnostic groups under the three encodinginstructions are shown in Figure 2. The main effect ofdiagnostic group was significant [F(1 ,30) = 28.96,p < .001], as was the effect of encoding instructions[F(2,30) = 42.57, p< .001]. The interaction betweenthese two variables was not significant [F(2,30) < 1] .

Multiple comparisons of the recall scores for theKorsakoff subjects across the three encoding instructionsshowed differences between Sand NS instructions[F(l ,30) = 37.62, p< .001] and between NS and Ninstructions [F(1,30) = 31.84, p< .001]. There wereno differences between the N and S instructed groups[F(1 ,30) < 1]. For subjects in the alcoholic groups,there were differences between means for the NS andS instructions [F(2,30)= 30.47, p< .001] and betweenNS and N instructions [F(2,30) = 27.87, p< .001].There were no differences between Sand N instructions[F(2,30) < 1] .

Between-group comparisons showed subjects in the

ENCODING AND RETRIEVAL IN KORSAKOFF PATIENTS 237

80

90 0-0 Alconolics

0-0 Korsakoffs

NS N S

ENCODING INSTRUCTIONS

Figure 2. Mean percentage correct recall for Korsakoff andalcoholic groups in the presence of category cues at recall, as afunction of encoding instructions.

• Atcoholics

° Korsakoffs

8 - Cued...... Uncued

conditions are presented in Figure 3. The main effect ofdiagnostic category was significant [F(l,60) = 47.35,p < .001], as were those of encoding instructions[F(2,60) = 40.06, p< .001] and cuing at time of recall[F(l ,60) = 27.62, p < .001]. The Encoding by Cueinteraction was significant [F(2,60) = 3.71, P < .05].No significant interactions were obtained for Diagnosisby Eneoding [F(2,60) = 1.06] or Diagnosis by Cue[F(2,60) < 1). There was a significant Diagnosis byEncoding by Cuing interaction [F(2,60) = 2.54, p< .05] .

In the absence of cues at the time of recall, Korsakoffsubjects showed differences in recall between NS and Sinstructions [F(l,60)= 16.93, p<.OOl] and betweenSand N instructions [F(l ,60) = 15.85, n< .001]. Therewere no differences in recall between NS and Ninstructions [F(l ,60) < 1] . When cues were provided attime of recall, Korsakoff subjects showed no differencesin recall between N and S instructions [F(l ,60) < 1] .N instructions, however, resulted in higher recallperformance than the NS instructions [F(1 ,60) = 20.36,p < .001] . Analysis of the Cuingby Encoding Instructioninteraction showed that cuing at the time of recallresulted in a significant increase for N instructions[F(l ,60) =53.29, p< .001] and for S instructions[F(l ,60) = 12.84, p< .01] , but not for NS instructions[F(1,60) = 3.96]. The results support the fmdingsobtained in Experiments 1 and 2 and show that, withoutcuing at the time of recall, Korsakoff subjects withoutspecific encoding instructions do not increase theirrecall output above the level of a group receivinginstructions to encode nonsemantically. The groupwithout explicit encoding instructions, when providedwith cues at the time of recall, increased their perform­ance to a level that is similar to a group of Korsakoffsubjects receiving semantic encoding instructions pluscues at recall time.

• 0

70

10

-i

<Ifr:0::

90::

3uu.J

~ 3zu.Ju5200..

alcoholic group to have higher recall scores thanKorsakoff subjects for NS instructions [F(2,30) = 11.79,p< .01], for N instructions [F(2,30) = 9.40, p < .01],and for S instructions [F(2,30) = 7.96, P < .01].

Figure 2 shows that when Korsakoff subjects areprovided with semantic cues at the time of recall, theinteraction effect between diagnostic group andencoding instructions does not reach significance.Comparison of Figure 1 with Figure 2 shows that whenGroup N was provided with cues at recall time, recallscores were improved as compared with Group Nwithout such cuing. In order to establish the generalityof these findings while preserving internal consistency,a third experiment was designed to replicate the previoustwo independent ones, thus providing a direet compari­son between the effects of eue vs. no cue for the threeinstruction groups.

NS N SENCODING INSTRUCTIONS

Figure 3. Mean percentage correct recall for Korsakoff andalcoholic groups as a function of encoding instructions and thepresence or absence of cues at recall.

EXPERIMENT 3

MethodSubjects were 72 male patients who had served in neither

Experiment 1 nor Experiment 2. Thirty-six subjects had beendiagnosed as alcoholic Korsakoff patients, while 36 had beendiagnosed as alcoholic and served as the control group. The meanage of the Korsakoff group was 56.32 years (range: 43-67 years),and the mean IQ was 93.00 (range: 81-110). The mean age ofthe alcoholic group was 57.33 years (range: 39-66 years), andthe mean IQ was 96.36 (range: 88-104). Subjects within eachof the two diagnostic groups were random1y assigned to one ofthree encoding instruction groups. Subjects within each ofthe groups were further divided into a group receiving categorylabel cues at the time of recall and a group receiving no cues atthe time of recall.

Results and DiscussionThe mean percentage eorreet recall scores for the two

diagnostic groups under the different eneoding and cuing

70

-i 60<i:uii' 5>-fr:0::

3u

l5«>-ztJ 200::ur0..

10

.----------0/f~ ...:y//:...........................•...

238 McDOWALL

GENERAL DISCUSSION

Cermak and Butters (1973) argued that Korsakoffpatients are unable to encode stimuli semanticallywithout specific instructions to do so. The results ofExperiment 1 taken by themselves provide support forthis theory, in that Korsakoff subjects receiving noexplicit encoding instructions showed a recall perform­ance that was not significantly different from a groupreceiving instructions to encode nonsemantically. Inaddition, both groups showed recall levels that werelower than a group instructed to encode semantically.The results of Experiment 2, however, do not supportasemantic encoding deficit theory.

The provision of semantic cues at the time of recallshould produce different results, depending on the levelof encoding performed on the stimuli. According to theencoding specificity hypo thesis (Tulving & Thomson,1973), retrieval cue effectiveness is a function of theencoding operations performed on the stimuli at thetime of presentation. Stimuli encoded at a nonsemanticlevel should gain little benefit from semantic cuesprovided at recall, and evidence that this is so in normalsubjects has been provided by Fisher and Craik (1977).Figure 3 shows that when semantic cues are providedat the time of recall to a group of Korsakoff subjectsinstructed to encode nonsemantically, no increase inrecall is noted. The same semantic cues provided to agroup of Korsakoff subjects instructed to encodesemantically results in a significant increase in recallperformance. For the group of Korsakoff subjects notprovided with explicit encoding instructions, semanticcues at the time of recall increases recall performancesignificantly strongly to suggest that the initial encodingoccurred at a semantic level, allowing semantic cues tobe effective.

If Korsakoff subjects were encoding along semanticdimensions without specific instructions to do so, why,in Experiment 1, was their recall performance similar tothat of the group instructed to encode nonsemantically?Alternatively, why was their recall level not similar tothat of the group instructed to encode semantically?There are at least two possibilities to account for thisfinding. The first hypothesizes that the group receivingno encoding instructions encoded stimuli along semanticlevels but to a lesser extent than the group specificallyinstructed to encode semantically, the higher recallperformance in the latter group reflecting a deeper andmore complete level of encoding. This view, however,is weakened by the results obtained in Experiment 2,in which providing cues at the time of recall increasedperformance in both the group receiving no encodinginstructions and the group receiving semantic encodinginstructions to a similar level. Presumably, if the initiallevel of encoding in the group receiving no explicitencoding instructions was less complete than the groupinstructed to semantically encode, the extent of the

recall increase obtained when semantic cues wereprovided at recall should not have been equivalent forboth groups.

The second hypothesis states that there was nodifference in the levels of semantic encoding performedby the group receiving no encoding instructions andthe group receiving semantic encoding instructions.The difference in recall between the two groups isaccounted for by hypothesizing that for the groupreceiving instructions to encode semantically, categorylabels were presented to the subjects during the learningphase, thus providing them with direct access tosuperordinate retrieval cues. Subjects receiving noencoding instructions were not provided with suchcues and, presumably, would have had to generatetheir own retrieval cuing strategy to aid recall. Thelow recall performance obtained by this group implies animpairment in the ability to generate such cues.

The results obtained by the alcoholic groups morenearly approximate the fmdings found in studiesmanipulating encoding instructions in normal subjects(Hyde, 1973; Hyde & Jenkins, 1973). Thus instructionsto semantically encode resulted in higher recall perform­ance than instructions to encode nonsemantically, anda group receiving no explicit encoding instructionsrecalled at a level similar to a group instructed to encodesemantically.

The fmdings of this study are not in completeagreement with those obtained by Wood and Kinsbourne(Note I), who found with Korsakoff subjects thatprecuing, that is, providing the category names at thetime of presentation, did not benefit recall in theabsence of any postcuing, that is, providing categorylabels at the time of recall. Essentially, the maindifference in methodology between the two studies liesin the task requirements of the subjects. In the presentstudy, subjects receiving semantic encoding instructionswere required to assign words to their appropriatesuperordinate labels. The finding that all Korsakoffsubjects were able to do this ensured that semanticencoding was achieved. Wood and Kinsbourne (Note 1)provided subjects with the to-be-remembered wordsalong with their appropriate category labels. There wasno way of ensuring that this procedure encourageda semantic encoding procedure or that subjects usedthe labels to provide a retrieval strategy.

The present study implicates an impairment in theability of Korsakoff subjects to generate their ownappropriate retrieval cues during recall, although theycan use retrieval cues when they are provided. Fuld(1976) has suggested that encoding an item in such away as to allow consistent retrieval may require thatitems within a list be related semantically to each other.In other words, encoding along semantic levels per semay not allow effective retrieval unless the semanticrelationships among the words are perceived andencoded, for example, by linking them to some super-

ENCODING AND RETRIEVAL IN KORSAKOFF PATIENTS 239

ordinate label. In the absence of specific cues at recalltime, identification of superordinate labels or higherorder units probably depends on perceiving semanticsimilarity among items. In the present study, thecategorized word list was always presented with theconstraint that no two members of the same categoryfollow each other. Thus, conceptually related itemswere not immediately available for some form oforganization. The group instructed to semanticallyencode in effect provided organization to the word listby linking individual items to their superordinate labels.

A related problem is the finding that Korsakoffsubjects are impaired in the rate at which they processstimuli (Cermak et al., 1974; Oscar-Berrnan et al., 1973).Korsakoff subjects may require more time in order tosufficiently encode words such that their categoricalnatures are perceived. This may apply particularly whencategorized word lists are presented in a nonblockedmanner (i.e., when words are not grouped by category).

Finally, note should be taken of a study by Stoff andEagle (1971), who found a positive correlation betweenthe reported strategies adopted by normal subjects inmemory tasks and their scores on the similarities subtestof the WAlS. In particular, subjects who recalled wordsby adopting an organizational strategy, that is, byorganizing words according to semantic relatedness,had higher scores on the similarities subtest than didsubjects who reported using no such organiza tionalstrategy. The authors noted that the adoption ofan organizational strategy and performance on thesimilarities sub test have in common the examinationof semantic relationships among words. These findingsare related to the present study in that Korsakoffsubjects typically perform very poorly on the similaritiessubtest. The mean scaled score on the similarities subtestfor Korsakoff subjects combined across the three experi­ments (N = 72) was 4.39; for the a1coholic subjects(N = 72), the mean score was 7.39. The failure toorganize words into their appropriate conceptualcategories, which in turn may be at least partly due toan impaired rate of stimulus processing, may be relatedto the failure to generate retrieval cues at the time ofrecall.

REFERENCE NOTE

l. Wood. F.• & Kinsbourne. M. Paper in symposium on path­ologieal torgetting. International Neuropsyehologieal Society,February 8. 1974. Boston.

REFERENCES

BREGMAN. A. S. Forgetting curves with semantic, phonetic,graphie. and contiguity cues. Journal ot Experimental Psychol­ogy, 1968. 78. 539-546.

CERMAK. L. S. Human memory: Research and theory. New York:Ronald Press. 1972.

CERMAK. L. S.. & BUTTERS. N. The role otinterference and encod­ing in thc short-term mernorv deticits 01' Korsakoff patients ,Ncuml's\'choluuia. 1\,)72. 10.1\\.)-1.)5.

CERMAK. L. S.. &: BUTTERS. N. Information processing deficits 01'alcoholic Korsakoff paiicnts. Quurtcriv Journal o( St udics onAlcohol, 1\.)7.1.34. 1110-11.12.

CERMAK. L. S.. BUTTERS. N.. & GERREIN. J. The extent 01' theverbal eneoding ability 01' Korsakoffpatients. Neuropsychologia,1\.)73, 11.85-\,)4.

CERMAK. L. S.. BUTTERS. N. &: MOREINES. 1. Some analyses ofthe verbal encoding deficit 01' alcoholic Korsakoff patients. Brain(~ Lunguuge, 1\,)74. I. 141-150.

CARIK. F. I. M.. & LoCKHART. R. S. Levels ofprocessing: A frame­work for mernory research. Journal ot Verbal Learning andVerbal Bchuvior, 1\.)72. 11. b71-684.

CRAIK. F. I. M.. & TULVING. E. Depth 01' processing and therctention 01' words in episodie mernory. Journal otExperimentalPsvchclogv. General, 1975. 104. 26S-294.

FISHER. R. P.. &: CRAIK. F. I. M. Interaction between eneodingand rctrieval operations in eued recall. Journal ojExperimentalPsvchologv. Human Leurning and Memorv. 1977. 3. 701-711.

FUI~. P. A·. Storage. retention. and retriev~1 in Korsakoffs syn­drornc. Neuropsvchologia, 1\.)70. 14. 225-236.

Hv DE. T. S. Differential eftects 01' effort and type of orienting taskon recall and organization 01' highly associated words. JournalutExpcrimcntul Psychology, )\,)73.97.111-113.

HYDE. T. S.. &: JENKINS. 1. 1. Recall for words as a funetion 01'scrnantic, graphie. and syntactie orienting tasks. Journalot'Verbal Lcurning and Verbal Behavior, 1973. 12.471-480.

JAFFE. P. G.. &: KATZ, A. N. Attenuating anterograde amnesiain Korsakoff's psychosis. Journal 01' Abnormal Psychology.1\,)75. 84. 559-562.

MEISSNER. W. W. Learning and memory in the Korsakoff syn­dromc.ln/enw/ionalJournal otNeuropsychiatry. 1968. January­Fcbruary. 0-20.

ÜSCAR-BERMAN. M.. GOODGLASS. H.. & CHERLOW. D. G. Percep­tual laterality and iconic recognition of visual materials byKorsakoll patients and normal adults. Journal o] Comparativeund Phvsiologicul Psvchology . 1\,)73. 82. 316-321.

PETERSON. L. R.. & PETERSON. M. J. Short-terrn retention ofindi­vidu al verbal items. Journal otExperimental Psychology, 1959.58. 1\,)3-1\,)8.

STOFF. D. M.. & EAGLE. M. N. The relationship among reportedstratcgies. prescntation rate. and verbal ability and their effectsOll trec recall learning. Journal ot' Experimental Psychology,\471. 87. 423-428.

TALLAN D. G. Psychologieal studies 01' Korsakoff's psychosis, 1II.Concept forrnation. Journal o( Nervous and Mental Disease .1459. 128.214-226.

TAI.LAND. G. Deranged memory, New York: Academie Press.1%5.

Tu.r., R. E.. &: JENKINS. 1. J. The effccts of eued orienting tasksOll free recall 01' words. Journal o( Verbal Learning and VerbalHch avior, 147.3. 12. 489-498.

TULVING. E.. & THOMSON, D. M. Encoding speeificity andretrieval processes in episodic memory. Psychological Review.1473. 80. 352-373.

Vrcrox. M.. HERMAN. K.. & WHiTE. E. E. A psychological studyof rhc Wernicke·Korsakoff syndrome: Results 01' Wechsler­Bellevue Intelligenee Seale and Wechsler Memory Scale testingat different stages in the disease. Quarterly Journal of Studies()II Alcohul. 1959. 20. 467-47\').

VICTOR. M.. & YAKOVLEV, P. I. S. S. Korsakoffs psyehie disorderin conjunction with peripheral neuritis, a translation ofKorsakoffs original article with brief comments on the authorand his contribution to clinical medicine. Neurology, 1955. S.3\,)4-406.

WARRINGTON. E. K.. &: WEISKRANTZ. L. Arnnesia: Consolidationor ret rieval? Na/ure. 1970.228.628-630.

WARRINGTON. E. K.. & WEISKRANTZ, L. ürganizational aspectsot memorv in amnesic patients. Neuropsychologia, 1971. 9.07-73.

WARRINGTON. E. K.. & WEISKRANTZ. L. The effeet 01' priorlearning on subsequent retention in amnesie patients. Neuro­I's\'chulogia. 1974, 12.419-428.

WIC·KENS. D. D. Encoding categories 01' words: An empiricalapproach 10 meaning. Psychological Review, 1970. 77. 1-15.

I Reccivcd tor publication July 11. 1978;rcvision aecepted Febru ary 15. 1979.)