The future-orientation of memory: Planning as a key component mediating the high levels of recall found with survival processing

In a series of papers, Nairne and colleagues have demonstrated that tasks encouraging participants to judge words for relevance to survival led to better recall than did tasks lacking survival relevance. Klein, Robertson, and Delton (2010) presented data suggesting that the future-directed temporal orientation of the survival task (e.g., planning), rather than survival per se, accounts for the good recall found with the task. In the present studies we manipulated the amount of survival and planning processing encouraged by a set of encoding tasks. Participants performed tasks that encouraged processing stimuli for their relevance to (a) both survival and planning, (b) planning, but not survival, or (c) survival but not planning. We predicted, and found, that recall performance associated with tasks encouraging planning (i.e., survival with planning and planning without survival) should exceed tasks that encouraged survival but not planning (i.e., survival without planning). We draw several conclusions. First, planning is a necessary component of the superior recall found in the survival paradigm. Second, memory, from an evolutionary perspective, is inherently prospective—tailored by natural selection to support future decisions and judgements that cannot be known in advance with certainty.     

The use of cue familiarity during retrieval failure is affected by past versus future orientation

Cue familiarity that is brought on by cue resemblance to memory representations is useful for judging the likelihood of a past occurrence with an item that fails to actually be retrieved from memory. The present study examined the extent to which this type of resemblance-based cue familiarity is used in future-oriented judgments made during retrieval failure. Cue familiarity was manipulated using a previously-established method of creating differing degrees of feature overlap between the cue and studied items in memory, and the primary interest was in how these varying degrees of cue familiarity would influence future-oriented feeling-of-knowing (FOK) judgments given in instances of cued recall failure. The present results suggest that participants do use increases in resemblance-based cue familiarity to infer an increased likelihood of future recognition of an unretrieved target, but not to the extent that they use it to infer an increased likelihood of past experience with an unretrieved target. During retrieval failure, the increase in future-oriented FOK judgments with increasing cue familiarity was significantly less than the increase in past-oriented recognition judgments with increasing cue familiarity.     

The future-orientation of memory: planning as a key component mediating the high levels of recall found with survival processing

In a series of papers, Nairne and colleagues have demonstrated that tasks encouraging participants to judge words for relevance to survival led to better recall than did tasks lacking survival relevance. Klein, Robertson, and Delton (2010) presented data suggesting that the future-directed temporal orientation of the survival task (e.g., planning), rather than survival per se, accounts for the good recall found with the task. In the present studies we manipulated the amount of survival and planning processing encouraged by a set of encoding tasks. Participants performed tasks that encouraged processing stimuli for their relevance to (a) both survival and planning, (b) planning, but not survival, or (c) survival but not planning. We predicted, and found, that recall performance associated with tasks encouraging planning (i.e., survival with planning and planning without survival) should exceed tasks that encouraged survival but not planning (i.e., survival without planning). We draw several conclusions. First, planning is a necessary component of the superior recall found in the survival paradigm. Second, memory, from an evolutionary perspective, is inherently prospective--tailored by natural selection to support future decisions and judgements that cannot be known in advance with certainty.     

Processing strategies and secondary memory in very rapid forgetting

When a memory test is unexpected, recall performance is quite poor at retention intervals as short as 2–4 seconds. Orienting tasks that change encoding conditions are known to affect forgetting in such “very rapid forgetting” paradigms where people are misled to believe that recall will not be required. We evaluated the hypothesis that differences in forgetting among orienting tasks are attributable to contributions of secondary memory during encoding in two experiments. In Experiment 1, short-term recall performance was inversely related to task demands during encoding, although long-term memory performance was not. Task demands were assessed by making the duration of stimulus presentation dependent on the time required to perform three different orienting tasks. In Experiment 2, we compared performance of that variable-length stimulus presentation to the fixed-length presentation used in most prior research. The results suggested that additional encoding or rehearsal time does not have an appreciable impact on short-term performance. Thus, differences in forgetting appeared to be a function of the contribution of secondary memory rather than a function of the time available to engage in primary memory rehearsal strategies.     

Time in the eye of the beholder: Gaze position reveals spatial-temporal associations during encoding and memory retrieval of future and past

Time is grounded in various ways, and previous studies point to a “mental time line” with past associated with the left, and future with the right side. In this study, we investigated whether spontaneous eye movements on a blank screen would follow a mental timeline during encoding, free recall, and recognition of past and future items. In all three stages of processing, gaze position was more rightward during future items compared to past items. Moreover, horizontal gaze position during encoding predicted horizontal gaze position during free recall and recognition. We conclude that mental time line and the stored gaze position during encoding assist memory retrieval of past versus future items. Our findings highlight the spatial nature of temporal representations.     

Remembering the past and imagining the future: attachment effects on production of episodic details in close relationships

Attachment theories and studies have shown that Internal Working Models (IWMs) can impact autobiographical memory and future-oriented information processing relevant to close relationships. According to the constructive episodic simulation hypothesis (CESH), both remembering the past and imagining the future rely on episodic memory. We hypothesised that one way IWMs may bridge past experiences and future adaptations is via episodic memory. The present study investigated the association between attachment and episodic specificity in attachment-relevant and attachment-irrelevant memory and imagination among young and older adults. We measured the attachment style of 37 young adults and 40 older adults, and then asked them to remember or imagine attachment-relevant and attachment-irrelevant events. Participants’ narratives were coded for internal details (i.e., episodic) and external details (e.g., semantic, repetitions). The results showed that across age group, secure individuals generated more internal details and fewer external details in attachment-relevant tasks compared to attachment-irrelevant tasks; these differences were not observed in insecure individuals. These findings support the CESH and provide a new perspective to understand the function of IWMs.     

Familiarity and personal experience as mediators of recall when planning for future contingencies

In this article, we demonstrate that planning tasks enhance recall when the context of planning (a) is self-referential and (b) draws on familiar scenarios represented in episodic memory. Specifically, we show that when planning tasks are sorted according to the degree to which they evoke memories of personally familiar scenarios (e.g., planning a picnic), recall is reliably superior to tasks that fail to do so (e.g., planning an Arctic trek). We discuss the implications of these findings for planning tasks and their relation to episodic memory.     

Encoding information for future action: Memory for to-be-performed tasks versus memory for to-be-recalled tasks

What is the nature of the representation underlying memory for future tasks such as calling the doctor or buying milk? If this representation consists of a verbal instruction that is translated into action at the time of retrieval, then memory should be better when tested via verbatim recall of the instruction than when tested via actual performance. Three experiments rejected this possibility, indicating better memory for a perform mode of report than for a recall mode of report. This was true in Experiment 1 in which subjects saw a series of verbal instructions (e.g., “move the eraser,” “lift the cup,” “touch the ashtray”), with advance information regarding the mode of report required during testing. In Experiment 2, the advance cue was valid only in 75% of the trials. Memory depended more heavily on the expected mode of report thanon the actual mode ofreport, suggesting that the perform superiority is due to processes that occur during encoding. In Experiment 3, subjects learned 20 phrases depicting minitasks were remembered by subjects tested via performance than by subjects tested via verbatim recall. A second part of Experiment 3 also indicated superior memory when a perform test was expected, regardless of which mode of report was actually required. The results were compared with the finding that subject-performed tasks are better remembered thanare their verbal instructions, which suggeststhat the representation underlying memory for future assignments-may-take advantage of the imaginal-enactive properties ofthe envisagedacts. Other possible differences between memory for to-be-recalled tasks and memory for to-be-performed tasks are discussed.     

"When did I learn and when shall I act?": The developmental relationship between episodic future thinking and memory

This study investigated the development of the ability to reflect on one’s personal past and future. A total of 64 4- to 6-year-olds received tasks of delayed self-recognition, source memory, delay of gratification, and a newly developed task of future-oriented action timing. Although children’s performance on delayed self-recognition, source memory, and action timing improved with age, their performance on delay of gratification did not. Children’s errors in source memory and action timing were solely and strongly associated with each other in older children (5–6 years) even after controlling for age and verbal ability. Results are discussed in terms of mental time travel underlying episodic memory and future thinking that includes both the projection of oneself into the past and future and the appreciation of events’ temporal relations.     

Separating past and future autobiographical events in memory: Evidence for a reality monitoring asymmetry

After thinking about the past and imagining the future, how do people separate these real and imagined events in memory? We had subjects engage in past and future autobiographical elaboration, then later take memory tests that required them to recollect these earlier generated events. In Experiment 1, testing memory for previously generated past or future autobiographical events led to fewer source memory confusions than did an elaborative control task, suggesting that the distinctive features of autobiographical elaboration improved subsequent retrieval monitoring accuracy. In Experiment 2, we directly compared retrieval monitoring accuracy for previously generated past and future autobiographical events and found that subjects made fewer source confusions when searching memory for future events. This asymmetry suggests that the features characterizing future elaborations (e.g., cognitive operations) were used more effectively during reality monitoring than were the features characterizing past elaborations (e.g., perceptual details), and has implications for future-oriented theories of memory.     

When remembering the past suppresses memory for future actions

Remembering planned actions at the correct time in the future is an integral component of prospective cognition. Recent studies on future remembering have led to suggestions that prospective cognition might be based on past experience. To test this hypothesis, we focused on retrieval-induced forgetting (RIF), which usually indicates that remembering past events suppresses memory for related but different past events. The current study assessed RIF in two kinds of event-based prospective memory (PM) tasks using either focal or non-focal cues for ongoing tasks. Participants studied six members from each of eight taxonomic categories and then practiced recalling three of the six members from four of the eight categories using category-stem cues. This retrieval practice suppressed the detection of non-practiced members of the practiced categories during the PM task with non-focal cues (Experiment 1) but not with focal cues (Experiment 2). The results suggest that recall of certain items inhibits the function of the others as PM cues, but only if the PM task does not largely share its processing with the ongoing task.     

Retrieval of past and future positive and negative autobiographical experiences

We studied retrieval-induced forgetting for past or future autobiographical experiences. In the study phase, participants were given cues to remember past autobiographical experiences or to think about experiences that may occur in the future. In both conditions, half of the experiences were positive and half negative. In the retrieval-practice phase, for past and future experiences, participants retrieved either half of the positive or negative experiences using cued recall, or capitals of the world (control groups). Retrieval practice produced recall facilitation and enhanced memory for the practised positive and negative past and future experiences. While retrieval practice on positive experiences did not impair the recall of other positive experiences, we found inhibition for negative past and future experiences when participants practised negative experiences. Furthermore, retrieval practice on positive future experiences inhibited negative future experiences. These positivity biases for autobiographical memory may have practical implications for treatment of emotional disorders.     

Short-term memory stages in sign vs. speech: the source of the serial span discrepancy

Speakers generally outperform signers when asked to recall a list of unrelated verbal items. This phenomenon is well established, but its source has remained unclear. In this study, we evaluate the relative contribution of the three main processing stages of short-term memory – perception, encoding, and recall – in this effect. The present study factorially manipulates whether American Sign Language (ASL) or English is used for perception, memory encoding, and recall in hearing ASL-English bilinguals. Results indicate that using ASL during both perception and encoding contributes to the serial span discrepancy. Interestingly, performing recall in ASL slightly increased span, ruling out the view that signing is in general a poor choice for short-term memory. These results suggest that despite the general equivalence of sign and speech in other memory domains, speech-based representations are better suited for the specific task of perception and memory encoding of a series of unrelated verbal items in serial order through the phonological loop. This work suggests that interpretation of performance on serial recall tasks in English may not translate straightforwardly to serial tasks in sign language.     

Differentiating between verbal and spatial encoding using eye-movement recordings

Visual information processing is guided by an active mechanism generating saccadic eye movements to salient stimuli. Here we investigate the specific contribution of saccades to memory encoding of verbal and spatial properties in a serial recall task. In the first experiment, participants moved their eyes freely without specific instruction. We demonstrate the existence of qualitative differences in eye-movement strategies during verbal and spatial memory encoding. While verbal memory encoding was characterized by shifting the gaze to the to-be-encoded stimuli, saccadic activity was suppressed during spatial encoding. In the second experiment, participants were required to suppress saccades by fixating centrally during encoding or to make precise saccades onto the memory items. Active suppression of saccades had no effect on memory performance, but tracking the upcoming stimuli decreased memory performance dramatically in both tasks, indicating a resource bottleneck between display-controlled saccadic control and memory encoding. We conclude that optimized encoding strategies for verbal and spatial features are underlying memory performance in serial recall, but such strategies work on an involuntary level only and do not support memory encoding when they are explicitly required by the task.     

Rewarded remembering: dissociations between self-rated motivation and memory performance

People often claim that they perform better in memory performance tasks when they are more motivated. However, past research has shown minimal effects of motivation on memory performance when factors contributing to item-specific biases during encoding and retrieval are taken into account. The purpose of the present study was to examine the generality of this apparent dissociation by using more sensitive measures of experienced motivation and memory performance. Extrinsic motivation was manipulated through competition instructions, and subjective ratings of intrinsic and extrinsic motivation were obtained before and after study instructions. Participants studied a series of words, and memory performance was assessed by content recall (Experiment 1) and source recall (Experiment 2). Both experiments showed dissociation between subjective ratings of extrinsic motivation and actual memory performance, so that competition increased self-rated extrinsic motivation but had no effects on memory performance, including source recall. Inconsistent with most people's expectations, the findings suggest that extrinsic motivation has minimal effects on memory performance.     

The development and coherence of future-oriented behaviors during the preschool years

Although previous research has identified a number of interesting aspects of future thinking in adults, little is known about the developmental trajectory and coherence of future-oriented behaviors during early childhood. The primary goal of this study was to explore these issues by administering a battery of tasks assessing different aspects of future thinking, including mental time travel, delay of gratification, planning, and prospective memory, to 72 preschoolers. Results revealed that performance on all of the tasks increased significantly between 3 and 5 years of age. Although most tasks were correlated, suggesting “behavioral” coherence, many of these significant correlations dropped out once age and receptive vocabulary were controlled. These results are discussed with respect to theories about, and measurement of, future orientation.     

Explaining variance in long-term recall in 3- and 4-year-old children: The importance of post-encoding processes

Long-term recall is influenced by what originally was encoded as well as by the efficacy of retrieval processes. The possible explanatory role of post-encoding processes by which initially labile memory traces are stabilized and integrated into long-term memory (i.e., consolidated) has received relatively less research attention. In the current research, we examined 3- and 4-year-old children's recall of multi-step event sequences immediately after seeing them modeled as a measure of encoding, 1week later as a measure of the status of the memory trace post-encoding, and 1month later as an assessment of long-term recall. We tested recall of events with three different levels of internal structure and with three different levels of support for retrieval. Measures of the post-encoding status of the memory trace explained significant variance in long-term recall when they were the sole predictors of performance, and they contributed unique variance in long-term recall even after accounting for the variance associated with encoding. The results imply that a complete explanation of forgetting during childhood must include not only roles for encoding and retrieval processes but also roles for post-encoding processes.     

Developmental differences in episodic memory across school ages: evidence from enacted events performed by self and others

The aim of this study was to examine action memory as a form of episodic memory among school-aged subjects. Most research on action memory has focused on memory changes in adult populations. This study explored the action memory of children over time. A total of 410 school-aged child participants, comprising 201 girls and 208 boys in four age groups (8, 10, 12, and 14), were included in this study. We studied two forms of action encoding, subject-performed tasks (SPTs) and experimenter-performed tasks (EPTs), which were compared with one verbal encoding task as a control condition. At retrieval, we used three memory tests (free recall, cued recall, and recognition). We observed significant differences in memory performance in children aged 8–14 years with respect to free recall and cued recall but not recognition. The largest memory enhancement was observed for the SPTs in the 8–14-year-old participants under all test conditions. Participants performed equally well on the free recall of SPTs and EPTs, whereas they displayed better performances on the cued recall and recognition of SPTs compared to EPTs. The strategic nature of SPTs and the distinction between item-specific information and relational information are discussed.     

The association between past and future oriented thinking: Evidence from autism spectrum disorder

A number of recently developed theories (e.g., the constructive episodic simulation, self-projection, and scene construction hypotheses) propose that the ability to simulate possible future events (sometimes referred to as episodic future thinking, prospection, or foresight) depends on the same neurocognitive system that is implicated in the recall of past events (episodic memory). In this paper, we argue that autism spectrum disorder (ASD) offers an ideal test of such theories, given that it is a developmental disorder that is characterized by impairments in episodic memory. Each of these theories would predict concomitant impairments in episodic future thinking among individuals with ASD. We review evidence concerning episodic future thinking in ASD, as well as studies of prospective memory (remembering to do something in the future), planning, navigation, and theory of mind, which some theories suggest also rely on the same mechanism as episodic future thinking.     

Short-term retention of a single word relies on retrieval from long-term memory when both rehearsal and refreshing are disrupted

Many working memory (WM) models propose that the focus of attention (or primary memory) has a capacity limit of one to four items, and therefore, that performance on WM tasks involves retrieving some items from long-term (or secondary) memory (LTM). In the present study, we present evidence suggesting that recall of even one item on a WM task can involve retrieving it from LTM. The WM task required participants to make a deep (living/nonliving) or shallow (“e”/no “e”) level-of-processing (LOP) judgment on one word and to recall the word after a 10-s delay on each trial. During the delay, participants either rehearsed the word or performed an easy or a hard math task. When the to-be-remembered item could be rehearsed, recall was fast and accurate. When it was followed by a math task, recall was slower, error-prone, and benefited from a deeper LOP at encoding, especially for the hard math condition. The authors suggest that a covert-retrieval mechanism may have refreshed the item during easy math, and that the hard math condition shows that even a single item cannot be reliably held in WM during a sufficiently distracting task—therefore, recalling the item involved retrieving it from LTM. Additionally, performance on a final free recall (LTM) test was better for items recalled following math than following rehearsal, suggesting that initial recall following math involved elaborative retrieval from LTM, whereas rehearsal did not. The authors suggest that the extent to which performance on WM tasks involves retrieval from LTM depends on the amounts of disruption to both rehearsal and covert-retrieval/refreshing maintenance mechanisms.