Adaptive memory: Determining the proximate mechanisms responsible for the memorial advantages of survival processing.

J. S. Nairne, S. R. Thompson, and J. N. S. Pandeirada (2007) suggested that our memory systems may have evolved to help us remember fitness-relevant information and showed that retention of words rated for their relevance to survival is superior to that of words encoded under other deep processing conditions. The authors present 4 experiments that uncover the proximate mechanisms likely responsible. The authors obtained a recall advantage for survival processing compared with conditions that promoted only item-specific processing or only relational processing. This effect was eliminated when control conditions encouraged both item-specific and relational processing. Data from separate measures of item-specific and relational processing generally were consistent with the view that the memorial advantage for survival processing results from the encoding of both types of processing. Although the present study suggests the proximate mechanisms for the effect, the authors argue that survival processing may be fundamentally different from other memory phenomena for which item-specific and relational processing differences have been implicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Congruity effects between materials and processing tasks in the survival processing paradigm.

Nairne, Thompson, and Pandeirada (2007) reported a series of experiments in which processing unrelated words in terms of their relevance to a grasslands survival scenario led to better retention relative to other semantic processing tasks. The impetus for their study was the premise that human memory systems evolved under the selection pressures of our ancestral past. In 3 experiments, we extended this functional approach to investigate the congruity effect—the common finding that people remember items better if those items are congruent with the way in which they are processed. Experiment 1 was a replication of Nairne et al.’s (2007) experiment and showed congruity effects in the survival processing paradigm. To avoid potential item-selection artifacts from randomly selected words, we manipulated congruence between words and processing condition in Experiments 2 and 3. As expected, final recall was highest when the type of processing and the materials were congruent, indicating that people remember stimuli better if the stimuli are congruent with the goals associated with their processing. However, contrary to our predictions, no survival processing advantage emerged between the 2 congruent conditions or for a list of irrelevant words. When congruity was controlled in a mixed list design, the survival processing advantage disappeared. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Retrieval monitoring and anosognosia in Alzheimer's disease.

This study explored the relationship between episodic memory and anosognosia (a lack of deficit awareness) among patients with mild Alzheimer's disease (AD). Participants studied words and pictures for subsequent memory tests. Healthy older adults made fewer false recognition errors when trying to remember pictures compared with words, suggesting that the perceptual distinctiveness of picture memories enhanced retrieval monitoring (the distinctiveness heuristic). In contrast, although participants with AD could discriminate between studied and nonstudied items, they had difficulty recollecting the specific presentation formats (words or pictures), and they had limited use of the distinctiveness heuristic. Critically, the demands of the memory test modulated the relationship between memory accuracy and anosognosia. Greater anosognosia was associated with impaired memory accuracy when participants with AD tried to remember words but not when they tried to remember pictures. These data further delineate the retrieval monitoring difficulties among individuals with AD and suggest that anosognosia measures are most likely to correlate with memory tests that require the effortful retrieval of nondistinctive information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Response bias in "remembering" emotional stimuli: A new perspective on age differences.

Older adults sometimes show a recall advantage for emotionally positive, rather than neutral or negative, stimuli (S. T. Charles, M. Mather, & L. L. Carstensen, 2003). In contrast, younger adults respond "old" and "remember" more often to negative materials in recognition tests. For younger adults, both effects are due to response bias changes rather than to enhanced memory accuracy (S. Dougal & C. M. Rotello, 2007). We presented older and younger adults with emotional and neutral stimuli in a remember-know paradigm. Signal-detection and model-based analyses showed that memory accuracy did not differ for the neutral, negative, and positive stimuli, and that "remember" responses did not reflect the use of recollection. However, both age groups showed large and significant response bias effects of emotion: Younger adults tended to say "old" and "remember" more often in response to negative words than to positive and neutral words, whereas older adults responded "old" and "remember" more often to both positive and negative words than to neutral stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the recollection of specific- and partial-source information

Memory judgments can be based on information that is more or less specific with respect to the source of an item. The authors introduce a procedure and multinomial model for measuring specific- and partial-source information. In 2 experiments, participants heard words spoken by 4 different voices: 2 male voices and 2 female voices. During the test, participants were required to remember who spoke the test items (e.g., Male 1, Male 2, Female 1, Female 2, or new word). Participants often remembered information about the gender of the source (i.e., partial-source information) when they did not remember information that identified the source itself (i.e., specific-source information). Dividing attention during retrieval impaired participants' memory for specific-source information (i.e., voice information) but did not affect memory for partial-source information (i.e., gender information).     

Directed forgetting between, but not within, dissociative personality states.

To investigate amnesia between identities in dissociative identity disorder (DID), the authors assessed explicit and implicit memory performance on a directed-forgetting task in 12 DID patients who switched from one state to an "amnesic" state between presentation and memory testing. DID patients were instructed either to remember or to forget neutral and emotional words. Besides an overall decrease in explicit memory, patients demonstrated selective forgetting of to-be-forgotten, but not of to-be-remembered words in the amnesic state. Patients did not exhibit any directed forgetting within the same state. Implicit memory was fully preserved across states. Independent of state, patients recalled more emotional than neutral information. These results may extend the conceptualization of memory processes in DID, suggesting an important role for retrieval inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Processing personal information about well-known others and the self: The use of efficient cognitive schemata.

Investigated the efficiency with which personality information about highly familiar others and the self is processed and retained in memory. 18 undergraduates (aged 19–24 yrs) made yes/no personality ratings on 48 personal adjectives (e.g., resourceful, orderly). Half of the adjectives were rated for self-reference, whereas half were rated for applicability to a well-known other target person. Each S selected a highly familiar other to rate, and rating times (RTs) were recorded for all of the personality judgments. After the ratings, Ss were given an unexpected free recall test, in which they were required to write down as many of the personal adjectives as they could remember. Findings indicate that for both the self-referent and well-known other conditions, yes-rated recalled words had significantly shorter RTs than nonrecalled words. This pattern suggests the existence of efficient cognitive schemata for representing and interpreting personal information about these targets. A model of other-referent personal information processing is presented. Central to this model is the proposal that familiarity level is a critical determinant of the cognitive structures and processes implicated in other-referent processing. (French abstract) (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recall and stem-completion priming have different electrophysiological correlates and are modified differentially by directed forgetting.

The notion that different aspects of memory are assessed by explicit and implicit memory tests was supported by behavioral and electrophysiological results. In a study–test procedure, 24 Ss were instructed to remember some words and to forget other words. Free recall and cued recall were better for words associated with the remember instruction, whereas directed forgetting did not influence stem completion (an implicit memory test). Event-related brain potentials elicited during study differed as a function of subsequent memory performance for free recall and cued recall, but not for stem completion. These results implicate encoding differences in the distinction between the 2 types of memory test. Factors governing whether explicit retrieval affects performance on an implicit memory test, mechanisms that may underlie directed-forgetting effects, and the importance of electrophysiological correlates of memory are also discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

External and internal memory aids: When and how often do we use them?

Examined, in 3 experiments with a total of 489 undergraduates, the kinds of memory aids people use to help them remember in their daily lives. Depending on the situation, they may use internal aids (e.g., mental rehearsal, imagery) of the types usually studied in the laboratory or external aids (e.g., reminder notes, asking someone else), which are rarely investigated but may be often used. Ss' ratings and task performance indicated that they used external memory aids more often than internal aids (a) to prepare for future remembering than to remember past situations, (b) to remember spatial tasks than to remember verbal tasks, and (c) to remember to do things in the past than to remember information from the past. External aids were rated as more dependable, easier to use, more accurate, and more preferred than internal ones. Results indicate that at least 1 external aid, taking notes, affects encoding and not just retrieval, as shown by its facilitation of remembering even when the notes were not available as retrieval cues and its induction of greater categorization of the to-be-remembered items than the use of some other memory aids. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting affects both direct and indirect tests of memory.

In two experiments, subjects were instructed either to remember or to forget each word. Following study, two tests were given, one a direct test of memory requiring conscious recollection of the study list and the other an indirect test that could be performed without awareness of the study list. In Experiment 1, subjects recognized more remember than forget words (direct test) and completed more remember than forget fragments (indirect test) on both immediate and 1-week delayed tests. In Experiment 2, subjects showed superior recall (direct test) and greater repetition priming in lexical decision (indirect test) for remember than for forget words. The consistent directed forgetting effect on both types of tests is in accord with the idea that forget items are inhibited at the time of retrieval and that retrieval manipulations, unlike elaboration manipulations at encoding, affect direct and indirect tests in similar ways. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting of trauma cues in adult survivors of childhood sexual abuse with and without posttraumatic stress disorder

The authors used a directed-forgetting task to investigate whether psychiatrically impaired adult survivors of childhood sexual abuse exhibit an avoidant encoding style and impaired memory for trauma cues. The authors tested women with abuse histories, either with or without posttraumatic stress disorder (PTSD), and women with neither abuse histories nor PTSD. The women saw intermixed trauma words (e.g., molested), positive words (e.g., confident), and categorized neutral words (e.g., mailbox) on a computer screen and were instructed either to remember or to forget each word. Relative to the other groups, the PTSD group did not exhibit recall deficits for trauma-related to-be-remembered words, nor did they recall fewer trauma-related to-be-forgotten words than other words. Instead, they exhibited recall deficits for positive and neutral words they were supposed to remember. These data are inconsistent with the hypothesis that impaired survivors exhibit avoidant encoding and impaired memory for traumatic information.     

The development of memory efficiency and value-directed remembering across the life span: A cross-sectional study of memory and selectivity.

Although attentional control and memory change considerably across the life span, no research has examined how the ability to strategically remember important information (i.e., value-directed remembering) changes from childhood to old age. The present study examined this in different age groups across the life span (N = 320, 5–96 years old). A selectivity task was used in which participants were asked to study and recall items worth different point values in order to maximize their point score. This procedure allowed for measures of memory quantity/capacity (number of words recalled) and memory efficiency/selectivity (the recall of high-value items relative to low-value items). Age-related differences were found for memory capacity, as young adults recalled more words than the other groups. However, in terms of selectivity, younger and older adults were more selective than adolescents and children. The dissociation between these measures across the life span illustrates important age-related differences in terms of memory capacity and the ability to selectively remember high-value information. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Context effects on remembering and knowing: The expectancy heuristic.

Three experiments are reported examining the effect of context on remember-know judgments. In Experiments 1 and 2, medium-frequency words were intermixed with high-frequency or low-frequency words at study or at test, respectively. Remember responses were greater for medium-frequency targets when they were studied or tested among high-frequency, as compared with low-frequency, words. The authors proposed a decision-based mechanism called "the expectancy heuristic" to explain why remember responses were more likely when items were studied or tested in the context of words that were relatively less distinct. According to the expectancy heuristic, when items on a recognition test exceed an expected level of memorability they will be given a remember judgment but when they do not, but are still more familiar than new words, they will be given a know judgment. Experiment 3, which varied expectancies about the strength of tested targets, demonstrated the use of the expectancy heuristic, indicating that it operates by selectively influencing the remember criterion rather than by influencing recollection of studied items. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Multiple inputs to episodic memory: Words tell another story.

Seven patients with semantic dementia were asked to recall and recognize 10-word lists of object-name vocabulary preselected as either still "known" (correct picture naming and word-picture matching) or now "unknown" (incorrect picture naming and word-picture matching) to each individual patient. The patients showed a significant advantage for known words in immediate free recall after several learning trials and also in delayed recall and recognition. The majority of errors of commission for known words were semantic, whereas phonological errors, especially blends of target words, were produced in the unknown condition. These findings support claims that (a) multiple inputs from semantic and perceptual systems support episodic memory and (b) success in verbal and nonverbal episodic memory tasks is differentially dependent on semantic and perceptual information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Two separate verbal processing rates contributing to short-term memory span

Previous research indicates that verbal memory span, the number of words people can remember and immediately repeat, is related to the fastest rate at which they can pronounce the words. This relation, in turn, has been attributed to a general or global rate of information processing that differs among individuals and changes with age. However, the experiments described in this article showed that the rates of 2 processes (rapid articulation and the retrieval of words from short-term memory) are related to memory span but not to each other. Memory span depends on a profile of processing rates in the brain, not only a global rate. Moreover, there appears to be only a partial overlap between the rate variables that change with age and those that differ among individuals.     

The next-in-line effect: Encoding or retrieval deficit?

The phenomenon that people cannot remember what happens when they are next-in-line to perform was investigated in 2 experiments with 144 undergraduates to determine whether this memory deficit reflects a failure to encode or an inability to retrieve preperformance events. In Exp I, 96 Ss participated in 4 memory trials; in each trial, half the Ss were called on to read words, and the other half merely listened. Before each trial, Ss were told whether they would be readers or listeners and the order in which numbers would be called. Thus, readers could anticipate precisely when they would be called on to perform. After hearing the 28 words in random order, all Ss wrote down the recalled words on cued or noncued sheets. Although the semantic cues strongly facilitated access to memories, they did not moderate the next-in-line effect. In Exp II, Ss were told—either before or after performing—to make a special effort to remember preperformance events. If instructed afterward, Ss displayed the usual memory deficit. If instructed beforehand, they reversed the deficit and showed a superior preperformance recall. It is concluded that the next-in-line effect is a failure at encoding, not at retrieval. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Why are poor comprehenders inefficient searchers? An investigation into the effects of text representation and spatial memory on the ability to locate information in text.

Good comprehenders were more efficient than poor comprehenders when they were required to locate specific pieces of information in a text, and there were qualitative differences in search strategies between the groups. However, the performance of the good comprehenders was more like that of poor comprehenders when they were required to search through a scrambled text, suggesting that their search was guided by their representation of the content of the text. Although the groups did not differ in performance on a test of spatial memory, or on their ability to remember the location of individual words in a text, the good comprehenders were better at remembering the order in which specific words appeared in a text. This finding again suggests that their superior search strategies may arise because of their better memory for the order of events in a text. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory and emotion.

The purpose of this study by a 9th grade student "was to see if there were a relationship between memory and emotions." 121 Ss (junior high school students) viewed 30 words successively, each being exposed for a period of 2? sec., and then were instructed to recall them in writing. A week later dittoed lists of the same words were rated on a 5-point scale of unpleasantness-pleasantness by the Ss. "The difference in the kind of feeling, i.e., pleasant or unpleasant, seems to have no effect on memory… . Intensity of emotion does appear to affect memory." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Directed forgetting of emotional stimuli in borderline personality disorder.

On the basis of clinical literature, the authors hypothesized that individuals with borderline personality disorder (BPD) would show biased information processing when they were exposed to negative affective stimuli of a particular type. Individuals with BPD and controls were tested using a directed forgetting paradigm. Study participants were exposed to 3 types of words (borderline, neutral, positive) and were cued to either remember or forget each word as it was presented. There were no group differences on a free recall task for words in the remember condition. However, participants with BPD recalled significantly more of the borderline words from the forget condition than did controls. In other words, borderline participants remembered borderline words that they were instructed to forget. These results may be consistent with enhanced encoding of salient words and perhaps related themes in BPD individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adaptive memory: Survival processing increases both true and false memory in adults and children.

Research has shown that processing information in a survival context can enhance the information's memorability. The current study examined whether survival processing can also decrease the susceptibility to false memories and whether the survival advantage can be found in children. In Experiment 1, adults rated semantically related words in a survival, moving, or pleasantness scenario. Even though the survival advantage was demonstrated for true recall, there also was an unexpected increase in false memories in the survival condition. Similarly, younger and older children in Experiment 2 displayed superior true recall but also higher rates of false memories in a survival condition. Experiment 3 showed that in adults false memories were also more likely to occur in the survival condition when categorized lists instead of Deese-Roediger-McDermott (DRM)-like word lists were used. In all three experiments, no survival recall advantage was found when net accuracy scores that take the total output into account were used. These findings question whether survival processing is an adaptive memory strategy per se, as such processing not only enriches true recall but simultaneously amplifies the vulnerability to false memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)