Long–Term Recall Memory: Behavioral and Neuro–Developmental Changes in the First 2 Years of Life

Until not long ago, psychologists conceptually and methodologically linked the capacity for recall of the past to developments in language. With the advent of a nonverbal measure of recall, this association has been challenged. It now is apparent that the capacity for long–term recall emerges well before the verbal ability to describe past experiences. Long–term recall is newly (or recently) emergent late in the 1st year of life; over the 2nd year, it consolidates and becomes reliable. The course of age–related changes in mnemonic behavior is consistent with current understanding of developments in the neural substrate implicated in recall memory.     

Developments in long-term explicit memory late in the first year of life: behavioral and electrophysiological indices

Coincident with developments in the temporal-cortical explicit memory network, long-term recall abilities are newly emergent late in the first year of human life. We recorded event-related potentials (ERPs) in 9-month-olds as an index of the integrity of the neural substrate underlying a task thought to reflect explicit memory, namely, deferred imitation. ERP measures of recognition memory 1 week after unique laboratory experiences predicted whether and how much infants recalled of the experiences 1 month later. The findings further imply that memory storage and consolidation processes are a major source of variability in long-term recall memory late in the first year of life.     

As time goes by: Sixth graders remember a kindergarten experience

In this research we compared kindergarten children's immediate recall of a class field trip to a museum of archaeology on the same day of the trip to their recall 6 weeks later, 1 year later and 6 years later. Not surprisingly, children remembered less about this event over time. However, what children did recall was recalled as accurately and in as much detail 6 years after the trip as immediately after the trip. Most striking were the effects of cueing on memory over time. Without specific cues the event was forgotten by almost all of the children after 1 year, but with cues, 87 per cent of the children could recall details of the event even after 6 years. The set of ‘core’ activities which all children tended to recall on all recall trials were those activities that made this particular event distinctive. However, with increasing time since experiencing the event, children's recall tended to become more reconstructive and inferential. Thus, forgetting in autobiographic memory seems to involve three processes: decreases in amount recalled, changes in accessibility, and changes in memory content.     

The influence of an early interview on long‐term recall: a comparative analysis

Because of burgeoning participation by children in forensic situations there is significant concern about children's memory for stressful events. Influence of timing of the first interview and interview frequency on long‐term recall were evaluated by comparing three groups of 3‐ to 9‐year‐olds 1 year after an injury requiring emergency room treatment. One group had one interview, a year after injury; another group had two interviews, immediately and a year later; the third group had three interviews, immediately, 6 months and a year after injury. The type of event and timing of the initial interview influenced completeness and accuracy of recall after 1 year. All children showed extensive recall but having an immediate interview was associated with greater completeness and accuracy for 3–4‐year‐olds but not older children. This suggests a social influence: a highly structured and organized early interview may have beneficial effects on memory for preschoolers. Implications for questioning and testimony are discussed. Copyright © 2004 John Wiley & Sons, Ltd.     

Electrophysiological indices of memory for temporal order in early childhood: implications for the development of recollection

The ability to recall contextual details associated with an event begins to develop in the first year of life, yet adult levels of recall are not reached until early adolescence. Dual‐process models of memory suggest that the distinct retrieval process that supports the recall of such contextual information is recollection. In the present investigation, we used both behavioral and electrophysiological measures to assess the development of memory for contextual details, as indexed by memory for temporal order, in early childhood. Results revealed age‐related improvements in memory for temporal order despite similar levels of memory for the individual items themselves. Furthermore, this pattern of recall was associated with specific components in the electrophysiological response. Consistent with electrophysiological research in adults, distributed, positive‐going activity late in the waveform was associated with increases in recall of contextual details and the development of recollective processes.     

Updating in working memory: a comparison of good and poor comprehenders

In this research, we examined the relation between reading comprehension and success in a working memory updating task. We tested the hypotheses that poor comprehenders' deficiencies are associated with a specific difficulty in the working memory updating process, particularly in controlling for information that is no longer relevant. In the first experiment, groups of poor and good comprehenders, ages 8-11 years, were administered a working memory updating task. In the second experiment a year later, a subgroup of participants involved in the first experiment was tested with a different updating task. In both experiments, poor comprehenders had less accurate recall performance and made more intrusion errors than did good comprehenders. Moreover, distinguishing intrusion errors on the basis of their permanence in memory, we found that poor comprehenders were more likely to intrude items that were maintained longer in memory than were good comprehenders. This type of error predicted reading comprehension abilities better than did working memory recall. This suggests that the relation between reading comprehension and working memory is mediated by the ability to control for irrelevant information.     

The dawning of a past: the emergence of long-term explicit memory in infancy.

The ability to recall information about the past is thought to emerge in the 2nd half of the 1st year of life. Although there is evidence from both cognitive neuroscience and behavioral psychology to support this hypothesis, there is little longitudinal evidence with which the question can be addressed. Infants' memory abilities were tested between the ages of 9 and 16 months using elicited and deferred imitation. Infants' memory for events was tested after delays ranging from 1 to 6 months. The results suggest that at 9 months of age, infants are able to store and retrieve representations over delays of as many as 4 weeks but not over long delays. In contrast, 10-month-olds have at their disposal a system that allows encoding and retrieval of event representations over delays of up to 6 months. These results support the idea that the system that underlies long-term ordered recall emerges near the end of the 1st year of life.     

Providing misleading and reinstatement information a year after it happened: effects on long-term memory

The question addressed here is whether misleading suggestions made to children a year after target events had occurred will alter long-term recall. One group (3-13 years old when injured and treated in a hospital Emergency Room) were given both misleading and accurate reinstating information a year later, and recall of target events assessed both 1 week and another year later (i.e., 2 years post-injury). A control group had recall assessed both 1 and 2 years post-injury. Misleading had little effect on children's recall 1 week later, although a few misled details were reported. However, a year later virtually none of the misleading information was incorporated into long-term recall. Rather, children were more, not less, accurate when recalling details about which they had been misled. Results were attributed to target events having been highly memorable and well rehearsed via previous recalls, and detection of discrepancies between memory and misleading information focusing attention on targeted details.     

States of awareness across multiple memory tasks: obtaining a "pure" measure of conscious recollection

Four experiments were conducted to examine the nature of recollective experience across different explicit memory tests. Experiments 1 and 2 showed that the proportion of retrieved items that were given Remember responses were equivalent across free recall, category cued recall, category plus letter cued recall, and recognition memory tests unlike the result reported by Tulving [Can. Psychol. 26 (1985) 1]. Experiments 3 and 4 revealed that Remember judgments are influenced by both conceptual and perceptual variables not only in the recognition task but in other explicit memory tasks as well. Taken together, the empirical evidence from this study demonstrates that explicit memory performance is accompanied by different states of awareness not only in recognition but also across other memory tasks including free recall.     

The memory is in the details: Relations between memory for the specific features of events and long-term recall during infancy

The second year of life is marked by pronounced changes in the length of time over which events are remembered. We tested whether the age-related differences are related to differences in memory for the specific features of events. In our study, 16- and 20-month-olds were tested for immediate and long-term recall of individual actions and temporal order of actions of three-step sequences in an elicited imitation paradigm as well as for forced-choice recognition of the specific feature of the props used to produce the sequences. Memory for the props was related to long-term recall of the events only for the 20-month-olds. It accounted for unique variance above and beyond the variance explained by immediate recall of the individual actions and the temporal order of actions of the sequences. The different pattern of relations in the older and younger infants seemingly reflects a developmental difference in the determinants of long-term recall over the second year of life.     

When Even Arbitrary Order Becomes Important: Developments in Reliable Temporal Sequencing of Arbitrarily Ordered Events

By late in the first year of life, children show temporally ordered recall of event sequences, the orders of which are constrained by enabling relations; they do not reliably recall arbitrarily ordered events. Using elicited imitation, in two experiments, we examined age-and experience-related changes in young children's recall of events, the orders of which are arbitrary. The changes were found to have implications for the efficacy of verbal reminding and to be related to developments in language. Specifically, on the basis of a single experience, 16-month-olds did not accurately recall arbitrarily ordered event sequences either immediately or after a two-week delay (Experiment 1); 22-month-olds recalled the events immediately, but not after the delay; by 28 months, children recalled the events even after the delay (Experiment 2A). This development was accompanied by changes in the ability to benefit from verbal reminders: 28-month-olds' recall was facilitated by provision of verbal reminders, whereas that of the younger children was not. Moreover, age-related changes in accurate reproduction of lengthy arbitrarily ordered event sequences were found to be related to developments in language (Experiment 2B). Critically, the limitations on 1-year-olds' performance that are overcome with age are not absolute: After three experiences, 16-month-olds accurately recalled the events after a two-week delay; their recall was facilitated by verbal reminders (Experiment 1). The implications of these findings are discussed.     

Recall in Infancy: A Neurodevelopmental Account

ABSTRACT— Relations between developments in neural structures and changes in memory in infancy are a relatively recent focus of research. Greater knowledge about brain development, as well as methodological advances such as combined use of behavioral and electrophysiological techniques, have led to the generation and testing of specific hypotheses regarding sources of age-related change. Theory and data converge to suggest that the early-stage processes of encoding and consolidation are a significant source of age-related variability in memory early in life. Additional research is needed to determine how these processes change and interact with myriad other determinants of recall.     

Phonological short‐term memory and vocabulary development: further evidence on the nature of the relationship

The nature and generality of the developmental association between phonological short‐term memory and vocabulary knowledge was explored in two studies. Study 1 investigated whether the link between vocabulary and verbal memory arises from the requirement to articulate memory items at recall or from earlier processes involved in the encoding and storage of the verbal material. Four‐year‐old children were tested on immediate memory measures which required either spoken recall (nonword repetition and digit span) or recognition of a sequence of nonwords. The phonological memory–vocabulary association was found to be as strong for the serial recognition as recall‐based measures, favouring the view that it is phonological short‐term memory capacity rather than speech output skills which constrain word learning. In Study 2, the association between phonological memory skills and vocabulary knowledge was found to be strong in teenaged as well as younger children, indicating that phonological memory constraints on word learning remain significant throughout childhood. Copyright © 1999 John Wiley & Sons, Ltd.     

Recognition and recall in amnesics

Although there is considerable agreement that performance in direct memory tasks (e.g., recall, recognition) is more disrupted by amnesia than performance in indirect memory tasks (e.g., mirror reading, word completion), one may be able to further circumscribe the deficit within the domain of direct memory tasks. The present article explores whether recall is disproportionately disrupted by amnesia compared to recognition. If amnesia affects memory uniformly across different direct memory measures, recall of normal controls should not differ from the recall of amnesics when recognition scores of these two groups are equated. On the other hand, if recall is disproportionately disrupted, normal recall should be superior to amnesic recall even when recognition is equated. The present study equated amnesic recognition with that of controls by providing amnesics with 8 s of study time and normal subjects with 0.5 s. Amnesics with Korsakoff's syndrome, amnesics with other etiologies, and appropriate controls were examined. Normal recall was superior to amnesic recall even when no differences were found in recognition. The results further specify the selective nature of amnesia.     

Memory development in the second year: for events or locations?

We employed an object-placement/object-removal design, inspired by recent work on 'episodic-like' memory in scrub jays (Clayton, N. S., & Dickinson, A. (1998). Episodic-like memory during cache recovery by scrub jays. Nature, 395, 272-274), to examine the possibility that children in the second year of life have event-based memories. In one task, a successful search could have been due to the recall of an object-removal event. In the second task, a successful search could only have been caused by recall of where objects were located. Success was general in the oldest group of children (21-25 months), while performance was broadly similar on the two tasks. The parsimonious interpretation of this outcome is that the first task was performed by location memory, not by event memory. We place these data in the context of object permanence development.     

A year’s memories: The calendar effect in autobiographical recall

When asked to recall autobiographical events from the past year, students tend to recall more incidents from the beginning and the end of school terms than from other periods. We investigated thiscalendar effect in Experiment 1 by comparing free recall at schools with different academic calendars. The event distributions tracked the individual calendars, helping to eliminate the possibility that the calendar effect is due to seasonal, nonschool factors, such as holidays. In Experiments 2–4, we checked explanations based on the ideas that events at term boundaries are more important or distinctive than others, that events are incorrectly dated too near the boundaries, and that boundaries serve as implicit cues for recall. These experiments revealed no evidence that importance or errors in dating could explain the effect. Manipulating cues, however, did change the size of the effect, implicating retrieval from very long-term memory as the effect’s source. We suggest that when people have to search episodic memory, they consider their own calendar rhythms (such as a student’s academic schedule) and let the temporal structure of their personal context guide their search.     

Immediate and long-term retention of connected concrete discourse as a function of mnemonic picture-type sequence and context

Abstract.— Two stories each containing 30 sentences of connected, concrete discourse were presented with or without an illustrating picture preceding each sentence, and with or without within-story context. Immediate paced recall with pictures or empty frames was demanded. With the with-context material, paced recall and free recall was also studied after the lapse of one year. Storey 1 was made according to the en-route mnemonic scheme and story 2 according to the within-a-building scheme. On immediate recall pictures as well as context had a strong positive effect. There was no interaction between pictures and context., which may be interpreted to mean that these factors may be intrapsychically identical. Recall after one year was generally poor, but indicated that the en-route mnemonic scheme may be more effective in long-term memory. Very little reconstruction from the pictures seems to have taken place.     

Very Long-term Recall in Infants: Infantile Amnesia Reconsidered

Abstract

Subjects who had participated in a study on non-verbal recall before their first birthday returned to the laboratory one year later and were tested for recall of their previous visit. During their previous visit they had shown recall of both familiar and novel actions on a set of novel objects. However, after a year's delay, evidence for recall was found for the familiar actions only. One action in particular was responsible for this finding: feeding a teddy bear with a schematic bottle. The majority of the returning subjects who had been shown this action repeated it after a year, whereas none of the other returning subjects and few of the subjects in the control groups performed this action. The results indicate that young infants have the ability to recall an event both at 11 months of age and after a delay as long as one year. The finding that infants can recall during a period that later becomes inaccessible to memory is important to our understanding of infantile amnesia.     

The effect of a prior cognitive interview on children's acceptance of misinformation

This research examined whether a Cognitive interview facilitates correct recall in children aged 4 to 5 and 9 to 10 years, and whether a Cognitive interview given before post‐event misinformation reduces children's reporting of suggestions on subsequent memory tests. Children were presented with an event followed the next day by a Cognitive or a Memorandum interview. Children were then read a post‐event summary containing misleading suggestions. The next day all children were given both standard test and modified forced‐choice cued‐recall tests. The free recall phase of the Cognitive interview elicited the greatest number of correct details. Age differences were found such that 9‐ to 10‐year‐old children's reports were more accurate and more complete than those of the 4‐ to 5‐year‐olds. More correct person, action and object details were reported in a Cognitive interview. Misinformation effects were found in both age groups on the standard test whereas on the modified test such an effect was only found in the 4‐ to 5‐year‐olds. Children's reporting of suggestions was unaffected by prior interview. Copyright © 2003 John Wiley & Sons, Ltd.