Episodic memory and metamemory in Parkinson’s disease patients.

This study investigated episodic memory and metamemory for verbs and nouns in patients who have cognitive impairments associated with Parkinson’s disease (PD). PD patients and healthy control participants were asked to recall word pairs and provide feeling-of-knowing (FOK) judgments for the items they were unable to recall. This was followed by a 4-alternative recognition test. PD patients were impaired in both recall and recognition, compared with controls. In terms of metamemory, PD patients were less confident in their ability to recognize the unrecalled items in a future recognition test. Most important, accuracy of PD patients’ FOK judgments was not above chance and was lower than that of control participants. The PD group correctly recognized fewer verbs than nouns, but type of material (verb vs. noun) had no impact on recall or FOK judgments. In addition, contribution of executive functions to FOK accuracy was different in PD patients and controls. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Context affects feeling-of-knowing accuracy in younger and older adults.

In feeling of knowing (FOK) studies, participants predict subsequent recognition memory performance on items that were initially encoded but that cannot presently be recalled. Research suggests that FOK judgment magnitude may be influenced by the total amount, or quantity, of contextual information retrieved related to the unrecalled target (e.g., Koriat, 1993). The present study examined the contribution of quality of that information to episodic FOK judgments. In addition, we tested whether the episodic FOK deficit demonstrated by older adults could be reduced by encouraging retrieval of contextual information relevant to the target. Three experiments demonstrated that quality of the retrieved partial information influenced FOK judgments in both older and younger adults; however, the manifestation of that influence was age dependent. The results also indicated that older adults required explicit retrieval of contextual information before making FOK judgments in order to make accurate FOK predictions. The results suggest that FOK accuracy may be partially determined by search processes triggered when participants are queried for contextual information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Are you sure you forgot? Feeling of knowing in directed forgetting.

One significant issue in metamemory is how variables increasing memorability affect metamemory. Previous research has produced inconsistent results. The effect of directed forgetting on the magnitude and accuracy of feeling-of-knowing (FOK) judgments was investigated. Participants were presented with word pairs, some to be remembered and some to be forgotten, and then were asked to recall all target words regardless of initial instructions. For unrecalled items, they were asked to give FOK judgments about performance in a future memory task: a cued stem-completion task (Experiment 1) or a recognition test (Experiment 2). This encoding manipulation increased both the memory performance and the magnitude of FOK judgments. However, no such effect on the accuracy of FOK judgments was observed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparison of three predictors of an individual's memory performance: The individual's feeling of knowing versus the normative feeling of knowing versus base-rate item difficulty.

Compared the memory performance predictions of 168 undergraduates with normative item-difficulty predictions and with normative feeling-of-knowing (FOK) predictions. Ss attempted to recall the answers to general-information questions, made FOK judgments on nonrecalled items, and were subsequently administered a criterion test (relearning, perceptual identification, or 1 of 2 versions of recognition). Results indicate that, for predicting an S's criterion performance, the S's own FOK predictions were intermediate between 2 kinds of normative predictions: Ss' FOK predictions were more accurate than predictions derived from normative FOK ratings but were less accurate than predictions derived from base-rate item difficulty (normative probabilities of correct recall). Subsidiary analyses showed that factors other than unreliability were responsible for the partial inaccuracy of Ss' FOK. Possible ways to improve the accuracy of an individual's FOK predictions are discussed. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging, episodic memory feeling-of-knowing, and frontal functioning.

Groups of normal old and young adults made episodic memory feeling-of-knowing (FOK) judgments and took 2 types of episodic memory tests (cued recall and recognition). Neuropsychological tests of executive and memory functions thought to respectively involve the frontal and medial temporal structures were also administered. Age differences were observed on the episodic memory measures and on all neuropsychological tests. Compared with young adults, older adults performed at chance level on FOK accuracy judgments. Partial correlations indicated that a composite measure of frontal functioning and FOK accuracy were closely related. Hierarchical regression analyses showed that the composite frontal functioning score accounted for a large proportion of the age-related variance in FOK accuracy. This finding supports the idea that the age-related decline in episodic memory FOK accuracy is mainly the result of executive or frontal limitations associated with aging. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attribute information and the feeling-of-knowing.

Demonstrated with 24 undergraduates that feeling-of-knowing (FOK) judgments about unrecalled items predict subsequent recognition performance with accuracy. The purpose of the experiment was to examine the relation between access to partial attribute information and the tendency to make positive or negative FOK judgments about an unrecalled item from a recent study episode. 52 words with extreme connotations of good or bad were paired with semantically neutral words, and 28 buffer pairs also were included to minimize the target words. Results indicate that when Ss made positive FOK judgments, attribute identification was more accurate than when Ss made negative FOK judgments. However, positive guesses were also made even when Ss did not have access to accurate attribute information. The results suggest that FOK judgments depend on access to an attribute of an unrecalled item, but they do not exclude other variables and referents as sources for the same phenomenon. (French abstract) (15 ref) (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Retrieval Inhibition in Directed Forgetting Following Severe Closed-Head Injury.

A variant of the list method directed forgetting procedure was used to examine the role of inhibition in memory performance following severe closed-head injury (CHI). Twenty-four participants with severe CHI and 24 controls studied picture and word stimuli in both forget and remember conditions. Memory testing for the to-be-forgotten and to-be-remembered items consisted of a free-recall test followed by a source-monitoring task. Despite poorer recall performance, the participants with CHI exhibited a directed forgetting effect similar to that in controls. Item recognition scores indicated that the inhibited items were not forgotten but rather were items whose accessibility had been lowered. These findings suggest that residual memory deficits in patients with severe CHI are unlikely to reflect inefficient retrieval inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Feeling-of-knowing in fact retrieval: further evidence for preservation in early Alzheimer's disease

The ability to retrieve and monitor factual information varying in datedness (i.e., dated vs. contemporary) was examined in healthy older adults and patients in an early phase of Alzheimer's disease (AD). Subjects were given free recall and multiple-choice recognition tests of 48 general knowledge questions. For all questions not responded to in recall, subjects made feeling-of-knowing (FOK) judgments. Results indicated dementia-related deficits in both recall and recognition, although both groups showed better recall and recognition with the dated compared with the contemporary questions. Importantly, despite deficits in fact retrieval, the AD patients showed intact monitoring of stored knowledge, as indicated by equivalent FOK accuracy for both groups. In addition, FOK accuracy was similar for the dated and the contemporary information in both groups, suggesting independence between level of general knowledge and the ability to supervise information stored in memory.     

Age differences in feeling-of-knowing and confidence judgments as a function of knowledge domain.

For two semantic knowledge domains, general and computer-related, feeling-of-knowing (FOK) and confidence level (CL) ratings and their relative accuracy were assessed in young, middle-aged, and older adults, after test difficulty was equated across age groups. Global memory self-efficacy beliefs were also assessed for each domain. As expected, greater age was associated with poorer memory self-efficacy beliefs only in the computer domain. The oldest two groups were found to be more underconfident than young adults when rating their FOK but not their CL, for computer items but not for general items. Statistical control of age differences in memory self-efficacy beliefs in the relevant domain greatly reduced this age effect on computer-related FOK ratings. This finding suggests that absolute FOK judgments are more closely related to memory self-efficacy beliefs than are CL judgments. Gamma correlations between judgments and recognition performance revealed that all age groups were equally accurate in FOK and in CL judgments, in both domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

How do we know that we know? The accessibility model of the feeling of knowing

Even when Ss fail to recall a solicited target, they can provide feeling-of-knowing (FOK) judgments about its availability in memory. Most previous studies addressed the question of FOK accuracy, only a few examined how FOK itself is determined, and none asked how the processes assumed to underlie FOK also account for its accuracy. The present work examined all 3 questions within a unified model, with the aim of demystifying the FOK phenomenon. The model postulates that the computation of FOK is parasitic on the processes involved in attempting to retrieve the target, relying on the accessibility of pertinent information. It specifies the links between memory strength, accessibility of correct and incorrect information about the target, FOK judgments, and recognition memory. Evidence from 3 experiments is presented. The results challenge the view that FOK is based on a direct, privileged access to an internal monitor.     

Indirect influence on modality on direct memory for words and their modality: Closed-head-injured and control participants.

Twenty closed-head-injured (CHI) patients and 28 control participants were tested on recall and recognition of words. In addition, memory for modality (i.e., visual vs. auditory) of word presentation was measured directly (i.e., recognition) and indirectly (i.e., by its influence on word and modality recognition). As predicted, the CHI patients were impaired relative to controls on all of the direct memory tasks; that is, word recall, word recognition, and modality judgment. However, the CHI and control groups did not differ significantly on the magnitude of the modality effect (i.e., facilitation due to correspondence of modality in learning and test). The findings are interpreted in the theoretical framework that distinguishes between item (i.e., words) and source (i.e., modality) memory and between direct and indirect measures of memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Role of Familiarity in Episodic Memory and Metamemory for Music.

Participants heard music snippets of varying melodic and instrumental familiarity paired with animal-name titles. They then recalled the target when given either the melody or the title as a cue, or they gave name feeling-of-knowing (FOK) ratings. In general, recall for titles was better than it was for melodies, and recall was enhanced with increasing melodic familiarity of both the cues and the targets. Accuracy of FOK ratings, but not magnitude, also increased with increasing familiarity. Although similar ratings were given after melody and title cues, accuracy was better with title cues. Finally, knowledge of the real titles of the familiar music enhanced recall but had, by and large, no effect on the FOK ratings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intact perceptual and conceptual priming in temporal lobe epilepsy: Neuroanatomical and methodological implications.

Explicit memory appears to be supported by medical temporal lobe structures, whereas separate neocortical regions may mediate perceptual and conceptual implicit memory. Children and adults with temporal lobe epilepsy (TLE) and matched controls were administered experimental verbal memory tests. Performance on implicit tests--word identification and word generation--was contrasted with explicit recognition and recall. Encoding conditions emphasized either conceptual or perceptual aspects of study words and were crossed with presentation modality. The priming performance of participants with TLE did not differ from controls, but participants with TLE did show deficits on recognition and recall measures. Thus, intact left temporal cortex does not appear to be necessary for normal implicit memory performance, even when conceptual processing is emphasized at study or test. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Confidence level and feeling of knowing for episodic and semantic memory: an investigation of lorazepam effects on metamemory

The effects of lorazepam (0.026 or 0.038 mg/kg), a benzodiazepine, and of a placebo on metamemory, i.e. knowledge about one's own memory capabilities, were investigated in 36 healthy volunteers. Accuracy of confidence levels (CL) in the correctness of recalled answers and accuracy of feeling of knowing (FOK) the answers when recall fails were measured using a sentence memory task assessing episodic memory and a task consisting of general information questions and assessing semantic memory. Lorazepam impaired episodic memory. Unexpectedly, it also impaired performance in both the recall and recognition phases of the task assessing semantic memory, suggesting that it decreased the ability to distinguish between correct and incorrect information. In episodic memory, lorazepam 0.038 mg/kg-treated subjects exhibited an impaired CL accuracy, compared to placebo-treated subjects, and their FOK accuracy was at chance. In semantic memory, their overall CL and FOK accuracy was apparently spared. However, these subjects selectively overestimated their CL judgements for incorrect answers; moreover, secondary analyses showed that FOK accuracy for a subset of low-accuracy items was virtually nil. These results suggest that lorazepam impairs metamemory for both episodic and semantic memory.     

One declarative memory system or two? The relationship between episodic and semantic memory in children with temporal lobe epilepsy.

Objective: This study explored verbal semantic and episodic memory in children with unilateral temporal lobe epilepsy to determine whether they had impairments in both or only 1 aspect of memory, and to examine relations between performance in the 2 domains. Method: Sixty-six children and adolescents (37 with seizures of left temporal lobe onset, 29 with right-sided onset) were given 4 tasks assessing different aspects of semantic memory (picture naming, fluency, knowledge of facts, knowledge of word meanings) and 2 episodic memory tasks (story recall, word list recall). Results: High rates of impairments were observed across tasks, and no differences were found related to the laterality of the seizures. Individual patient analyses showed that there was a double dissociation between the 2 aspects of memory in that some children were impaired on episodic but not semantic memory, whereas others showed intact episodic but impaired semantic memory. Conclusions: This double dissociation suggests that these 2 memory systems may develop independently in the context of temporal lobe pathology, perhaps related to differential effects of dysfunction in the lateral and mesial temporal lobe structures. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Process demands of rejection mechanisms of recognition memory.

A surge of research has been conducted to examine memory editing mechanisms that help distinguish accurate from inaccurate memories. In the present experiment, the authors examined the ability of participants to use novelty detection, recollection rejection, and plausibility judgments to reject lures presented on a recognition memory test. Participants studied a list of word pairs that were arranged in a category relationship (both words from the same category) or an unrelated relationship (both words from different categories) under full or divided attention. At test, participants were given a yes/no recognition test in which they were to respond after seeing the test items for 400 ms or 2,800 ms. Some of the test items were rearranged word pairs that were consistent with the study relationship, whereas others were inconsistent with the study relationship. The results demonstrate that the participants required full attention at study to use novelty detection, recollection rejection, and plausibility judgments to reject lures. Moreover, the results indicate that a long response deadline at test was needed for participants to use both recollection rejection and plausibility judgments to reject lures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The use of source memory to identity one's own episodic confusion errors.

In 4 category cued recall experiments, falsely recalled nonlist common members, a semantic confusion error participants. Errors were more likely if critical nonlist words were presented on an incidental task, causing source memory failures called episodic confusion errors . Participants could better identify the source of falsely recalled words if they had deeply processed the words on the incidental task. For deep but not shallow processing, participants could reliably include or exclude incidentally shown category members in recall. The illusion that critical items actually appeared on categorized lists was diminished but not eradicated when participants identified episodic confusion errors post hoc among their own recalled responses; participants often believed that critical items had been on both the incidental task and the study list. Improved source monitoring can potentially mitigate episodic (but not semantic) confusion errors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impaired Implicit Memory for Gist Information in Amnesia.

In 2 experiments using a converging associates paradigm, the authors evaluated implicit memory for gist information in amnesic patients. In Experiment 1, participants saw multiple sets of associates, each converging on a nonpresented theme word, and were then tested using an implicit word stem completion test and an explicit cued recall test. Amnesic patients showed intact implicit and impaired explicit memory for studied words, but memory for nonpresented lures was impaired, regardless of retrieval instructions. To evaluate whether impaired implicit memory for lures was due to accelerated forgetting of gist information, short study lists were used in Experiment 2, each consisting of a single set of associates. Amnesics' implicit memory for lures was again impaired. These results point to an inability to encode robust gist representations as the cause of impaired gist memory in amnesia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conjunction errors, recollection-based rejections, and forgetting in a continuous recognition task.

Six experiments investigated conjunction memory errors (e.g., falsely remembering blackbird after studying parent words blackmail and jailbird) in a continuous recognition procedure with a parent-conjunction lag manipulation. In 4 experiments (1A, 1B, 2A, and 2B) "recollect" judgments, which indexed recall of parent words, showed that participants can use recollection to prevent conjunction errors. "Recollect" judgments, as well as overt recall of parent words (in Experiments 2A and 2B), dropped sharply from a lag of 0 to 1 word, then stabilized from a lag of 1 to 20 words. Thus, the "recollect" responses and overt recall demonstrate a step function of forgetting over short intervals. These data generalized to cued recall in Experiments 3A and 3B with the first morpheme (e.g., black) as the cue, though recall conjunction errors occurred infrequently relative to recognition conjunction errors. Overall, the results support the idea that automatic and controlled processes contribute to memory performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)