Episodic Memory Development Research Articles

Developmental differences in hippocampal and cortical contributions to episodic retrieval

Episodic memory, or the ability to form and retrieve conscious memories about specific past events, improves during childhood. Previous adult neuroimaging results indicate a central role of the hippocampus in episodic retrieval, but it is not clear whether the contribution of the hippocampus changes during development. Traditionally, developmental improvements in episodic retrieval have been thought to depend on strategic processes mediated by the prefrontal cortex (PFC), a region that is considered to have a protracted course of development relative to the hippocampus. The primary goal of the present study was to test the hypothesis that the development of episodic retrieval is also associated with changes in hippocampal function. Children ages 8- to 11-years-old and adults ages 18–25 (N = 41) encoded black and white line drawings surrounded by either a green or red border. Functional magnetic resonance imaging (fMRI) data were acquired while participants attempted to recall which colour was originally paired with each drawing. Correct recall of item-colour pairings indicated successful episodic retrieval. Activity in the anterior hippocampus, but not in the posterior hippocampus, was associated with episodic retrieval in adults, whereas activity in the posterior, but not in the anterior hippocampus, was associated with episodic retrieval in children. Developmental differences were also found in regions in anterior lateral PFC and posterior parietal cortex. Overall, these results support the view that the development of episodic memory is supported by functional changes in the hippocampus as well as in other critical cortical regions.

Developmental differences in the neural correlates of relational encoding and recall in children: An event-related fMRI study

Despite vast knowledge on the behavioral processes mediating the development of episodic memory, little is known about the neural mechanisms underlying these changes. We used event-related fMRI to examine the neural correlates of both encoding and recall processes during an episodic memory task in two different groups of school age children (8–9 and 12–13 years). The memory task was composed of an encoding phase in which children were presented with a series of unrelated pictorial pairs, and a retrieval phase during which one of these items acted as a cue to prompt recall of the paired item. Age-related differences in activations were observed for both encoding and recall. Younger children recruited additional regions in the right dorsolateral prefrontal and right temporal cortex compared to older children during successful encoding of the pairs. During successful recall, older children recruited additional regions in the left ventrolateral prefrontal and left inferior parietal cortex compared to younger children. The results suggest that the prefrontal cortex contributes to not only the formation of memories but also access to them, and this contribution changes with development. The protracted development of the prefrontal cortex has implications for our understanding of the development of episodic memory.

A Minimalist Approach to the Development of Episodic Memory

Episodic memory is usually regarded in a Conceptualist light, in the sense of its being dependent upon the grasp of concepts directly relevant to the act of episodic recollection itself, such as a concept of past times and of the self as an experiencer. Given this view, its development is typically timed as being in the early school‐age years (Perner, 2001;Tulving, 2005). We present a minimalist, Non‐Conceptualist approach in opposition to this view, but one that also exists in clear contrast to the kind of minimalism (‘episodic‐like’) espoused byClayton and Dickinson (1998)with regard to memory in food‐caching birds. While emphasising the nonconceptual elements of episodic memory (in common with the ‘episodic‐like’ approach) we also insist on the essentially phenomenological nature of the memory (as does the Conceptualist approach). We propose the third year of life as a plausible onset period. Our view is rooted in Kantian assumptions about the spatiotemporal content of experience (and thus of re‐experience) and about the synthetic unity of experience—and thus of re‐experience. We answer two objections to this position.

Episodic memory and episodic foresight in 3- and 5-year-old children

In the present study, we examined the development of episodic memory and episodic foresight. Three- and 5-year-olds were interviewed individually using a personalised timeline that included photographs of them at different points in their life. After constructing the timeline with the experimenter, each child was asked to discuss a number of different events: an event that happened yesterday, an event that happened earlier today, an event that would happen later today, and an event that would happen tomorrow. As judged by their parents, children's accounts were highly accurate. After controlling for age and language scores, there was a strong relation between amount of information reported about past and future events. Overall, 5-year-olds reported more total information than 3-year-olds; however, reports by 3-year-olds included a similar proportion of first-person reference as did reports by 5-year-olds. No age difference appeared in proportion of future-oriented talk. We conclude that the present task provides a promising method of exploring the emergence of mental time travel during early childhood.

Binding and strategic selection in working memory: A lifespan dissociation.

Working memory (WM) shows a gradual increase during childhood, followed by accelerating decline from adulthood to old age. To examine these lifespan differences more closely, we asked 34 children (10-12 years), 40 younger adults (20-25 years), and 39 older adults (70-75 years) to perform a color change detection task. Load levels and encoding durations were varied for displays including targets only (Experiment 1) or targets plus distracters (Experiment 2, investigating a subsample of Experiment 1). WM performance was lower in older adults and children than in younger adults. Longer presentation times were associated with better performance in all age groups, presumably reflecting increasing effects of strategic selection mechanisms on WM performance. Children outperformed older adults when encoding times were short, and distracter effects were larger in children and older adults than in younger adults. We conclude that strategic selection in WM develops more slowly during childhood than basic binding operations, presumably reflecting the delay in maturation of frontal versus medio-temporal brain networks. In old age, both sets of mechanisms decline, reflecting senescent change in both networks. We discuss similarities to episodic memory development and address open questions for future research.

The Development of Episodic Memory: Lifespan Lessons

Abstract— This article looks at the development of episodic memory (EM) in children from a lifespan perspective, focusing on studies that directly compare children’s patterns of memory performance to those of older adults. With training, children show greater improvements and higher levels of asymptotic performance than older adults even when they initially perform at the same or lower levels. Thus, the plasticity of EM appears to be greater in children than in older adults. Next, the article describes the two-component model of EM development, which delineates sets of mechanisms that may underlie EM differences between children and older adults. According to this model, EM requires the interaction between associative and strategic components. It posits that the associative component of EM is relatively mature by middle childhood and declines in old age. The strategic component of EM matures later than the associative component and also declines in old age. Empirical evidence supports the model, and the article discusses its relation to recent findings in developmental psychology and neuroscience. The article concludes that a lifespan perspective on EM helps to delineate the differences, commonalities, and dependencies among mechanisms that regulate its function and development.

Children's episodic memory.

Episodic memory develops during childhood and adolescence. This trajectory depends on several underlying processes. In this article, we first discuss the development of the basic binding processes (e.g., the processes by which elements are bound together to form a memory episode) and control processes (e.g., reasoning and metamemory processes) involved in episodic remembering. Then, we discuss the role of these processes in false-memory formation. In the subsequent sections, we examine the neural substrates of the development of episodic memory. Finally, we discuss atypical development of episodic memory. As we proceed through the article, we suggest potential avenues for future research. WIREs Cogni Sci 2011 2 365-373 DOI: 10.1002/wcs.114 For further resources related to this article, please visit the WIREs website.

Development of autonoetic autobiographical memory in school-age children: Genuine age effect or development of basic cognitive abilities?

This study investigated the mechanisms behind episodic autobiographical memory (EAM) development in school-age children. Thirty children (6–11years) performed a novel EAM test. We computed one index of episodicity via autonoetic consciousness and two indices of retrieval spontaneity (overall and EAM-specific) for a recent period (previous school year) and a more remote one (preschool years). Executive functions, and episodic and personal semantic memory were assessed. Results showed that recent autobiographical memories (AMs) were mainly episodic, unlike remote ones. An age-related increase in the indices of episodicity and specific spontaneity for recent AMs was mainly mediated by an age-related increase in the efficiency of the three cognitive abilities. Remote AMs varied only slightly with age (overall spontaneity), reflecting improvements in semantic abilities. Thus, EAM development in school-age children is essentially bound up with the increasing efficiency of cognitive abilities. Results are discussed in the light of models of childhood amnesia.

Episodic memory development: theory of mind is part of re‐experiencing experienced events

AbstractTwo experiments with 3½‐ to 6½‐year‐old children showed that theory‐of‐mind development is associated with the growth of episodic memory. Episodic memory was assessed by manipulating informational conditions such that they permit or prevent the formation of episodic memories in terms of re‐experiencing the recalled event. Only experienced events, e.g. seeing how one puts a picture of a frog into a box, can be remembered by re‐experience. Events known through indirect information cannot be re‐experienced, e.g. putting pictures into the box when blindfolded and being later shown on video what was on these cards. Children were also tested on a battery of theory‐of‐mind tasks assessing their understanding of the origins of knowledge. There was a significant interaction in both experiments showing that recall of directly experienced items improved in relation to indirectly presented items the higher children's theory‐of‐mind scores. The discussion suggests that episodic memory development is specifically linked to the growing ability to introspect an ongoing experience and interpret it as representing an actual past event. Copyright © 2007 John Wiley & Sons, Ltd.

Relations between episodic memory, suggestibility, theory of mind, and cognitive inhibition in the preschool child

The development of episodic memory, its relation to theory of mind (ToM), executive functions (e.g., cognitive inhibition), and to suggestibility was studied. Children (n= 115) between 3 and 6 years of age saw two versions of a video film and were tested for their memory of critical elements of the videos. Results indicated similar developmental trends for all memory measures, ToM, and inhibition, but ToM and inhibition were not associated with any memory measures. Correlations involving source memory was found in relation to specific questions, whereas inhibition and ToM were significantly correlated to resistance to suggestions. A regression analysis showed that age was the main contributor to resistance to suggestions, to correct source monitoring, and to correct responses to specific questions. Inhibition was also a significant main predictor of resistance to suggestive questions, whereas the relative contribution of ToM was wiped out when an extended model was tested.

Memory and Temporal Perspective: The Role of Temporal Frameworks in Memory Development

An account of the development of temporal understanding is proposed which links such understanding with the development of episodic memory. We distinguish between different ways of representing time in terms of the kinds of temporal frameworks they involve. Distinctions are made between frameworks that are perspectival or nonperspectival and those that represent recurrent sequences or particular times. Even primitive temporal understanding integrates both perspectival and nonperspectival components. However, since early frameworks are event-based and localized, they are not yet sufficient for episodic memory in that they do not enable the child to think of events as having occurred at particular points in time. We describe the emergence of new kinds of frameworks in terms of the development of temporal decentering. Two levels of temporal decentering are distinguished, with the higher level involving an appreciation of how event representations depend on one's temporal perspective.