# Between Encoding and Retrieval: Behavioral and Neural Indices of Reactivation in Children’s Memory Development

> **NIH NIH R21** · TEMPLE UNIV OF THE COMMONWEALTH · 2020 · $183,740

## Abstract

Project Summary
Accurate memory for a specific past event is a cornerstone of human cognition, allowing for the use of past
experiences to optimally guide future behaviors. Episodic memory underlies the ability for children make well-considered decisions, interact with others in a socially appropriate and develop the life narrative that gives
coherence to their self-concepts over time. Thus, it is imperative that we understand in detail how memory
develops in childhood, and how environmental factors may alter the typical developmental trajectories of
episodic memory. There has been much work on age-related differences in encoding and retrieval, and a range
of variables have been identified that contribute to age-related improvements in memory function, e.g., poor use
of encoding strategies. In contrast, how a critical phase of memory processing – memory consolidation –
develops in childhood has received little attention. This lack exposes a crucial scientific gap in our
understanding of memory development.
In this proposal we examine a key mechanism of memory consolidation called “replay” in the rodent literature,
post-encoding reactivation, in the human literature, and how it develops in childhood. This phenomenon was
first observed in rodents that were trained to navigate a maze while hippocampal place cell activity was
recorded. Later, during post-learning sleep, the neuronal firing patterns within hippocampal place cells
recapitulated the firing patterns present during the awake learning phase. Replay can also be observed during
periods of quiet wakefulness. This fact has been leveraged in the human literature by examining fMRI scans
from rest periods that follow periods of learning. Drawing on predictions derived from computational models of
memory, we ask whether poorer memory in children is partly accounted for by perturbed post-encoding
reactivation mechanisms. To address this question, both children and young adults will undergo an fMRI scan
while encoding associations between items and locations, interleaved with rest scans. We predict that factors
that compromise the integrity of the hippocampus, or the ability of the hippocampus to rapidly communicate
with neocortex, will alter reactivation and memory performance. Besides examining the key factor of age,
children from high and low socioeconomic status (SES) backgrounds will be tested. Low SES/high stress
environments have been associated with poorer memory and smaller hippocampi. In addition, we will measure
structural connectivity between the hippocampus and cortical regions using cutting-edge imaging techniques.
Thus we will examine whether age, environmental factors, and individual differences in structural connectivity
alter a key mechanism underlying memory consolidation, and how this set of variables affects the behavioral
expression of memory.

## Key facts

- **NIH application ID:** 9935105
- **Project number:** 5R21HD098509-02
- **Recipient organization:** TEMPLE UNIV OF THE COMMONWEALTH
- **Principal Investigator:** Ingrid R Olson
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $183,740
- **Award type:** 5
- **Project period:** 2019-09-01 → 2023-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9935105

## Citation

> US National Institutes of Health, RePORTER application 9935105, Between Encoding and Retrieval: Behavioral and Neural Indices of Reactivation in Children’s Memory Development (5R21HD098509-02). Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/grant/nih/9935105. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*