Spatial Location Memory in Amnesia: Binding Item and Location Information Under Incidental and Intentional Encoding Conditions

Items located within an array were presented to alcoholic Korsakoff and nonalcoholic mixed-etiology amnesics and to alcoholic and normal controls. Recognition memory for the locations of items was tested after incidental and intentional encoding. When equated on item recognition, neither Korsakoff amnesics nor alcoholic controls benefited from intentional, relative to incidental, encoding instructions. Furthermore, Korsakoff amnesics showed neither disproportionately impaired incidental nor intentional location recognition memory relative to alcoholic controls. In contrast, mixed-etiology amnesics profited significantly from intentional location acquisition relative to incidental instructions, and were impaired somewhat in incidental, but not intentional, location memory relative to normal controls. We discuss these data in relation to Mayes' (1992) contextual memory deficit hypothesis and Hirst's (1982) automatic encoding deficit account, and propose an alternative framework in which the location memory deficit observed in mixed-etiology amnesics is interpreted as a disruption to the ability to bind item and location information.     

Deficits in the implicit retention of new associations by alcoholic Korsakoff patients

Word-stem completion in the presence or absence of a paired associate was assessed for a group of amnesic Korsakoff patients and a group of alcoholic controls. Since neither group demonstrated facilitation in the presence of cues (Experiment 1), an analysis of the influence of instructions to remember the paired associates on cued word-stem completion was performed with college students (Experiment 2). Finding a positive effect of instructions led to a replication of the task with amnesic patients and alcoholic controls. Unfortunately, instructions to remember the pairs did not produce the facilitatory effect for either group nor for an age matched nonalcoholic control group. (Experiment 3). It was concluded that neither amnesics, chronic alcoholics, nor elderly controls had the ability to modify their analysis of verbal material as a function of retrieval expectations. As a consequence, neither group demonstrated the effect of contextual priming of word completions reported by P. Graf and D. L. Schacter (1985, Journal of Experimental Psychology: Learning, Memory and Cognition, 11, 501-518).     

A comparison of cognitive function in community-dwelling and institutionalized old people of normal intelligence

Two carefully matched groups of normal old people living in institutions or in the community were administered a neuropsychological cognitive test battery. In general, the institutionalized group performed worse than the community group. Discriminant function analysis identified a subgroup of high-functioning institutionalized subjects whose performance more closely resembled that of the community group than the remainder of the institutionalized group. Differences between the various groups were not due to differences in IQ, age, health, or other controlled variables. The critical tests that differentiated the groups were sensitive to impaired function in frontal and medial-temporal lobe brain regions. The results suggest a complex interaction involving effects of age and environmental factors on brain function and cognition.     

Cued recall in anterograde amnesia

After a single presentation of a word list, normal subjects exhibited better retention when prompted with semantic cues than with rhyme or letter cues. Alcoholic Korsakoff patients, patients receiving electroconvulsive therapy (ECT), and the patient N.A. exhibited impaired retention and, unlike control subjects, did not exhibit an advantage of semantic cues over letter and rhyme cues. Two experimental manipulations designed to equate the level of performance of amnesics and controls indicated that these amnesias could be understood as a reflection of weak memory strength that results from deficiencies in initial learning and retention. In addition, alcoholic Korsakoff patients appeared to have greater difficulty utilizing semantic cues than patients receiving ECT or patient N.A.     

Contextual cueing effects in the remote memory of alcoholic Korsakoff patients and normal subjects

This study examines the effects of contextual cueing on the remote memory of alcoholic Korsakoff patients and normal subjects. Naming of personalities who became famous in each of the five decades beginning 1935 was tested under two conditions: "no-context", in which minimal extraneous cues to identification were provided, and "context", where clear extraneous cues were available. Normal subjects performed better than Korsakoff patients, showed no evidence of a temporal gradient, and exhibited a contextual cueing advantage across all decades. In contrast, Korsakoff patients demonstrated a marked temporal gradient, and the contextual cueing advantage declined systematically as more recent decades were sampled. Further analyses demonstrated that the differential pattern of deficits shown by Korsakoffs and controls was not attributable to absolute differences in performance level. Theoretical implications of these data for explanations of Korsakoff retrograde amnesia are discussed.     

Amnesics Have a Disproportionately Severe Memopry Deficit for Interactive Context

Two experiments were used to compare the recognition memory of amnesic and normal subjects for intentionally encoded words (targets) and for incidentally encoded words that were meaningfully related to the targets and presented at the same time (interactive context). In both experiments the target recognition of the two groups was matched at a high level by presenting the amnesics with much shorter lists of words to remember. Experiment 1 compared 20 amnesics and their matched controls and showed that whereas the amnesics' recognition of the target words did not benefit significantly when they were presented together with their interactive context words (relative to their recognition when the target words were presented alone), that of the controls did. Experiment 2 compared 14 amnesics and their matched controls and showed that when patients and their controls were matched on their target word recognition in isolation, then the patients still showed worse recognition for the interactive context words. These effects were not found only in Korsakoff patients, and their size did not correlate with behavioural measures of frontal-lobe damage. It is concluded that amnesics may be more impaired at recognizing incidentally encoded interactive context than they are at recognizing target material, and this deficit may be an essential feature of the syndrome.     

Effects of encoding instructions and retrieval cuing on recall in Korsakoff patients

The relationship between the depth of encoding a word and its subsequent recall, either cued or noncued, was investigated in this study. In Experiment 1, Korsakoff subjects and alcoholic controls were shown a categorized word list under one of three different encoding instructions: (1) nonsemantic, that is, detecting the presence or absence of the letter “e” in each word, (2)semantic, that is, assigning words to their correct taxonomic category, and (3) no encoding instructions. Semantic encoding instructions resulted in higher recall for both diagnostic groups than the other instructions. In Experiment 2, subjects were again assigned to one of the three encoding instructions as in Experiment 1, but all groups received cues (category labels) at the time of recall. Cuing increased recall for all but the group receiving instructions to encode nonsemantically. Experiment 3 was a replication of the previous experiments. The results indicated that Korsakoff subjects were capable of encoding semantically without specific instructions to do so but were impaired in the ability to generate retrieval cues at the time of recall.     

Transfer of old ‘reactivated’ memory retrieval cues in rats

The present studies examined whether the retrieval of an old ‘reactivated’ memory could be brought under the control of new contextual cues. In Experiment 1 rats trained in one context were exposed to different contextual cues either immediately, 60 or 120 min after a cued reactivation of the training memory. When tested in the shifted context, subjects exposed shortly after reactivation treated the shifted context as the original context. This transfer diminished with longer post-reactivation delays. Experiment 2 replicated the basic finding and demonstrated that the transfer of the old retrieval cues was specific to the contextual cues present during exposure. These findings are consistent with previous research [i.e., Briggs, J. F., Fitz, K. I., & Riccio, D. C. (in press). Transfer of memory retrieval cues in rats. Psychonomic Bulletin & Review] showing the transfer of retrieval cues for a new memory, and demonstrating a similarity (in this case) between newly acquired and old reactivated memories.     

Overlooking the Obvious: Incentives to Lie

Over the years, people have searched for deception cues in the liar's behavior. However, the sender's incentives to lie might be more revealing than behavior. In Experiment 1, an incentive was developed that was predictive of lying. Judges with access to incentive information in addition to behavior achieved almost perfect lie/truth detection. This was not a result of the speakers' behavior being transparent (Experiment 2) but because incentive information was useful to separate lies from truths (Experiments 2 and 3). Experiment 3 revealed that people may forego perfectly diagnostic contextual cues to base their judgments on illusory behavioral cues.     

Context Memory in Korsakoff’s Syndrome

Memory for contextual information and target-context integration are crucial for successful episodic memory formation and are impaired in patients with Korsakoff's syndrome. In this paper we review the evidence for the notion that a context memory deficit makes an important contribution to the amnesia in these patients. First, we focus on anterograde memory for contextual (spatial and temporal) information. Next, the use of contextual cues in memory retrieval is examined and their role in retrograde amnesia and confabulation. Evidence on the role of contextual cues and associations in working memory is discussed in relation to the underlying neurocognitive mechanisms and their dissociation from long-term encoding. Finally, we focus on implicit learning of contextual information in Korsakoff patients. It can be concluded that Korsakoff patients are impaired in the explicit processing of contextual information and in target-context binding, both in long-term (retrograde and anterograde) memory and in working memory. These results extend the context memory deficit hypothesis. In contrast, implicit contextual learning is relatively preserved in these patients. These findings are discussed in relation to evidence of dysfunction of the extended diencephalic-hippocampal memory circuit in Korsakoff's syndrome.     

Age-related differences in spatial memory: effects of structural and organizational context

The authors examined effects of structural and organizational spatial context on younger and older adults' memory for an arrangement of dollhouse furniture pieces. For half of the participants, landmark objects (Experiment 1) and a floor plan beneath the array (Experiment 2) served as structural context during study and replacement. Organizational context was varied by grouping items randomly or as 6 rooms in a prototypical house. Two study and replacement trials were given. In Experiment 1, landmark structural cues improved younger adults' performance, whereas both age groups benefited from the floor plan in Experiment 2. In both experiments, positive effects of organizational context and trial occurred. Higher order interactions further revealed that structural and organizational context effects varied in size across trials, suggesting that both age groups used spatial contextual cues more effectively with practice. Implications of these results for current views on cognitive compensation in adulthood are discussed.     

Face value: testing the utility of contextual face cues for face recognition

The presence of multiple faces during a crime may provide a naturally-occurring contextual cue to support eyewitness recognition for those faces later. Across two experiments, we sought to investigate mechanisms underlying previously-reported cued recognition effects, and to determine whether such effects extended to encoding conditions involving more than two faces. Participants studied sets of individual faces, pairs of faces, or groups of four faces. At test, participants in the single-face condition were tested only on those individual faces without cues. Participants in the two and four-face conditions were tested using no cues, correct cues (a face previously studied with the target test face), or incorrect cues (a never-before-seen face). In Experiment 2, associative encoding was promoted by a rating task. Neither hit rates nor false-alarm rates were significantly affected by cue type or face encoding condition in Experiment 1, but cuing of any kind (correct or incorrect) in Experiment 2 appeared to provide a protective buffer to reduce false-alarm rates through a less liberal response bias. Results provide some evidence that cued recognition techniques could be useful to reduce false recognition, but only when associative encoding is strong.     

Encoding specificity in the alcoholic Korsakoff patient

A previous attempt to improve amnesic Korsakoff patients' retention of individual words resulted in only moderate improvement and, then, only under restricted conditions. It appeared that this occurred because the patients “forget” the instructed analysis of the word as well as the word itself. Consequently, the two experiments reported here sought to provide feature (Experiment 1) or associated (Experiment 2) cues at both input and output. In this manner relatively good performance was obtained, but only when semantic cues were “strongly” associated to the target words. Implications for an encoding specificity interpretation are drawn from these results.     

Flexible attention deployment in threatening contexts: An instructed fear conditioning study

Factors leading humans to shift attention away from danger cues remain poorly understood. Two laboratory experiments reported here show that context interacts with learning experiences to shape attention avoidance of mild danger cues. The first experiment exposed 18 participants to contextual threat of electric shock. Attention allocation to mild danger cues was then assessed with the dot-probe task. Results showed that contextual threat caused subjects to avert attention from danger cues. In the second experiment, 36 participants were conditioned to the same contextual threat used in Experiment 1. These subjects then were randomly assigned to either an experimental group, trained to shift attention toward danger cues, or a placebo group exposed to the same stimuli without the training component. As in Experiment 1, contextual threat again caused attention allocation away from danger in the control group. However, this did not occur in the experimental group. These experiments show that acute contextual threat and learning experiences interact to shape the deployment of attention away from danger cues. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

An ecological study of professors' memory for student names and faces: A replication and extension

Abstract

This experiment measured university professors' memory for the names and faces of current and former students over a two-semester span. If courses function as contextual retrieval cues for professors to remember their students, the passing of each semester should diminish the distinctiveness of these cues. Based on the Bruce and Young (1986) model of face recognition, we hypothesised that as contextual cues become less distinctive, performance should suffer more on name recall tests than on name or face recognition tests. We found that name free recall and portrait-cued name recall declined very sharply after one semester (6 months), and face recognition declined after two semesters (12 months), whereas name recognition remained perfect These results provide a general replication and extension of Bahrick (1984), and show that difficulties in recalling names cannot be due to any weakening of name representations in memory. We suggest that name recall may be dependent on contextual cues that become less distinctive with succeeding semesters.     

Effects of multisensory environmental stimulation on contextual conditioning in the developing rat

The effect of increased exposure to multisensory stimulation during development on conditioned freezing to contextual cues in preweanling Sprague-Dawley rats was examined. Rats given increased environmental stimulation exhibited long-term contextual conditioning at a younger age than rats that did not receive such stimulation when there was either low or moderate levels of conditioning (Experiments 1 and 2). These differences in contextual conditioning were not a result of the stimulated rats reacting differently to shock (Experiment 4) or merely freezing more than the nonstimulated rats in all situations (Experiment 3). The role of the glucocorticoid system in the enhanced contextual learning of stimulated preweanling rats and the advantages of the contextual conditioning procedure for studying the effects of environmental stimulation are discussed.     

Blocking and overshadowing between intra-maze and extra-maze cues: A test of the independence of locale and guidance learning

Rats were trained on an elevated maze where the rewarded alternative was defined either in terms of intra-maze cues (rubber or sandpaper flooring on rewarded and unrewarded arms, regardless of their position) or in terms of extra-maze cues (the correct arm always pointed toward a particular corner of the room, and was sometimes covered with rubber and sometimes with sandpaper), or where both sets of cues were simultaneously relevant. In Experiment 1 rats pretrained with either intra-maze or extra-maze cues alone relevant learned less about the other set of cues than non-pretrained control groups, when, in a second phase of the experiment, both sets of cues were simultaneously relevant. Experiment 2 confirmed that intra-maze cues could block extra-maze cues, and ruled out one alternative explanation of the results of Experiment 1. Experiment 3 showed that extra-maze cues overshadowed intra-maze cues, but that there was no reciprocal overshadowing of extra-maze by intra-maze cues. This was despite the fact that animals learned the intra-maze discrimination significantly faster than the extra-maze discrimination. Experiment 3 also suggested that rats did not solve the extra-maze discrimination by learning to approach or avoid specific extra-maze cues, but rather by locating the correct arm by reference to the entire set of extra-maze cues. The results suggest that locale or place learning and cue or guidance learning, in O'Keefe and Nadel's (1978) terminology, interact with one another in much the same way as does learning about any pair of stimuli in a Pavlovian conditioning experiment.     

Rhesus monkeys use geometric and nongeometric information during a reorientation task

Rhesus monkeys (Macaca mulata) were subjected to a place finding task in a rectangular room perfectly homogeneous and without distinctive featural information. Results of Experiment 1 show that monkeys rely on the large-scale geometry of the room to retrieve a food reward. Experiments 2 and 3 indicate that subjects use also nongeometric information (colored wall) to reorient. Data of Experiments 4 and 5 suggest that monkeys do not use small angular cues but that they are sensitive to the size of the cues (Experiments 6, 7, and 8). Our findings strengthen the idea that a mechanism based on the geometry of the environment is at work in several mammalian species. In addition, the present data offer new perspectives on spatial cognition in animals that are phylogenetically close to humans. Specifically, the joint use of both geometric and landmark-based cues by rhesus monkeys tends to demonstrate that spatial processing became more flexible with evolution.     

Analysis of apparent demonstrations of responding in accordance with relational frames of sameness and opposition

We evaluated whether contextual control over equivalence and nonequivalence and responding by exclusion can explain the outcomes of relational frame theory (RFT) studies on sameness and opposition relations. We trained nine college students to maintain and reverse conditional discriminations with X1 and X2 as contextual stimuli. In Experiment 1, X1 and X2 controlled derived stimulus relations (DSR) analogous to those controlled by Same and Opposite in RFT studies. These results can be explained by at least two hypotheses: X1 and X2 were cues for equivalence and nonequivalence and responding by exclusion, or for sameness and opposition. In Experiment 2, X1 and X2 controlled DSR predicted by the hypothesis that they were cues for equivalence and nonequivalence and responding by exclusion, and not predicted by the hypothesis that they were cues for sameness and opposition. The results of Experiment 2 and the functional equivalence of X1 and X2 with Same and Opposite in Experiment 1 suggest that Same and Opposite were cues for equivalence and nonequivalence and responding by exclusion in RFT studies.