Subjective experience of episodic memory and metacognition: a neurodevelopmental approach.

Episodic retrieval is characterized by the subjective experience of remembering. This experience enables the co-ordination of memory retrieval processes and can be acted on metacognitively. In successful retrieval, the feeling of remembering may be accompanied by recall of important contextual information. On the other hand, when people fail (or struggle) to retrieve information, other feelings, thoughts, and information may come to mind. In this review, we examine the subjective and metacognitive basis of episodic memory function from a neurodevelopmental perspective, looking at recollection paradigms (such as source memory, and the report of recollective experience) and metacognitive paradigms such as the feeling of knowing). We start by considering healthy development, and provide a brief review of the development of episodic memory, with a particular focus on the ability of children to report first-person experiences of remembering. We then consider neurodevelopmental disorders (NDDs) such as amnesia acquired in infancy, autism, Williams syndrome, Down syndrome, or 22q11.2 deletion syndrome. This review shows that different episodic processes develop at different rates, and that across a broad set of different NDDs there are various types of episodic memory impairment, each with possibly a different character. This literature is in agreement with the idea that episodic memory is a multifaceted process

The influence of prior knowledge on memory: A developmental cognitive neuroscience perspective

Across ontogenetic development, individuals gather manifold experiences during which they detect regularities in their environment and thereby accumulate knowledge. This knowledge is used to guide behavior, make predictions, and acquire further new knowledge. In this review, we discuss the influence of prior knowledge on memory from both the psychology and the emerging cognitive neuroscience literature and provide a developmental perspective on this topic. Recent neuroscience findings point to a prominent role of the medial prefrontal cortex (mPFC) and of the hippocampus (HC) in the emergence of prior knowledge and in its application during the processes of successful memory encoding, consolidation, and retrieval. We take the lateral PFC into consideration as well and discuss changes in both medial and lateral PFC and HC across development and postulate how these may be related to the development of the use of prior knowledge for remembering. For future direction, we argue that, to measure age differential effects of prior knowledge on memory, it is necessary to distinguish the availability of prior knowledge from its accessibility and use

How does episodic memory develop in adolescence?

Key areas of the episodic memory (EM) network demonstrate changing structure and volume during adolescence. EM is multifaceted and yet studies of EM thus far have largely examined single components, used different methods and have unsurprisingly yielded inconsistent results. The Treasure Hunt task is a single paradigm that allows parallel investigation of memory content, associative structure, and the impact of different retrieval support. Combining the cognitive and neurobiological accounts, we hypothesized that some elements of EM performance may decline in late adolescence owing to considerable restructuring of the hippocampus at this time. Using the Treasure Hunt task, we examined EM performance in 80 participants aged 10-17 yr. Results demonstrated a cubic trajectory with youngest and oldest participants performing worst. This was emphasized in associative memory, which aligns well with existing literature indicating hippocampal restructuring in later adolescence. It is proposed that memory development may follow a nonlinear path as children approach adulthood, but that future work is required to confirm and extend the trends demonstrated in this study

Neonatal Brain Injury and Neuroanatomy of Memory Processing following Very Preterm Birth in Adulthood: An fMRI Study

Altered functional neuroanatomy of high-order cognitive processing has been described in very preterm individuals (born before 33 weeks of gestation; VPT) compared to controls in childhood and adolescence. However, VPT birth may be accompanied by different types of adverse neonatal events and associated brain injury, the severity of which may have differential effects on brain development and subsequent neurodevelopmental outcome. We conducted a functional magnetic resonance imaging (fMRI) study to investigate how differing degrees of neonatal brain injury, detected by neonatal ultrasounds, affect the functional neuroanatomy of memory processing in VPT young adults. We used a verbal paired associates learning task, consisting of four encoding, four cued-recall and four baseline condition blocks. To further investigate whether differences in neural activation between the groups were modulated by structural brain changes, structural MRI data were also collected. We studied 12 VPT young adults with a history of periventricular haemorrhage with associated ventricular dilatation, 17 VPT individuals with a history of uncomplicated periventricular haemorrhage, 12 individuals with normal ultrasonographic findings, and 17 controls. Results of a linear trend analysis demonstrated that during completion of the paired associates learning task right frontal and right parietal brain activation decreased as the severity of neonatal brain injury increased. There were no statistically significant between-group differences in on-line task performance and participants' intelligence quotient (IQ) at assessment. This pattern of differential activation across the groups was observed particularly in the right middle frontal gyrus during encoding and in the right posterior cingulate gyrus during recall. Structural MRI data analysis revealed that grey matter volume in the right superior temporal gyrus, right cerebellum, left middle temporal gyrus, right globus pallidus and right medial frontal gyrus decreased with increasing severity of neonatal brain injury. However, the significant between-group functional neuroanatomical differences were not directly attributable to the detected structural regional differences

Shaping memory consolidation via targeted memory reactivation during sleep

Recent studies have shown that the reactivation of specific memories during sleep can be modulated using external stimulation. Specifically, it has been reported that matching a sensory stimulus (e.g., odor or sound cue) with target information (e.g., pairs of words, pictures, and motor sequences) during wakefulness, and then presenting the cue alone during sleep, facilitates memory of the target information. Thus, presenting learned cues while asleep may reactivate related declarative, procedural, and emotional material, and facilitate the neurophysiological processes underpinning memory consolidation in humans. This paradigm, which has been named targeted memory reactivation, has been successfully used to improve visuospatial and verbal memories, strengthen motor skills, modify implicit social biases, and enhance fear extinction. However, these studies also show that results depend on the type of memory investigated, the task employed, the sensory cue used, and the specific sleep stage of stimulation. Here, we present a review of how memory consolidation may be shaped using noninvasive sensory stimulation during sleep

연합기억에서의 해마의 역할: 절제 연구와 뇌파 연결성 연구로부터의 통찰

학위논문(박사) -- 서울대학교대학원 : 자연과학대학 뇌인지과학과, 2023. 8. 정천기.연합 기억은 서로 관련없는 항목들의 관계에 대한 기억으로 정의됩니다. 해마는 연합기억에서 대체할 수 없는 중요한 역할을 하는 것으로 알려져 있습니다. 그러나, 해마가 단독으로 작용하여 연합 기억을 수행하는 것은 아니라는 점에 유의하는 것은 중요합니다. 연합 기억은 뇌의 여러 영역이 상호 작용하여 작동합니다. 따라서 연합 기억을 수행할 때 단순히 특정 영역이 활성화 되는 것 보다 해마와 기억 관련 네트워크 간의 기능적 연결이 더 중요할 수 있습니다. 먼저 해마가 연합 기억에 어떤 기여를 하는지 알아보기 위해 내측 측두엽 뇌전증으로 수술을 받은 환자를 대상으로 해마의 절제 여부와 수술 후 다양한 기억력 검사에서 나타난 기억력 변화 사이의 관계를 조사했습니다. 절제 영역과 위치의 개인차를 반영하는 복셀 기반 분석을 통해 해마의 절제가 항목 기억보다는 연합 기억의 저하와 관련이 있음을 발견했습니다. 이러한 이해를 바탕으로 저는 기억의 성공과 실패를 예측하기 위해 해마와 기억 관련 대뇌 피질 네트워크 영역 사이의 단일 시행 뇌파 연결성을 활용했습니다. 그 결과, 기억의 수행도를 예측할 때 평균 90% 이상의 정확도를 달성했습니다. 이 정확도는 특정 영역의 뇌 활동만을 예측에 사용하는 것과 비교했을 때 현저히 높은 수치입니다. 요약하자면, 이 논문은 연합 기억에서 해마와 해마의 연결성의 중요한 역할을 강조합니다. 이 연구는 연합 기억 과정을 이해하는 데 있어 특정 뇌 영역에만 초점을 맞추는 것이 아니라 대규모 기억 네트워크의 역할을 이해하는 것이 중요하다는 점을 강조합니다.Associative memory refers to the ability to remember the relationships between unrelated items. The hippocampus (HC) is known to play a critical and irreplaceable role in associative memory. However, it is important to note that the HC does not operate in isolation when it comes to performing associative memory; instead, it interacts with various regions of the brain. Therefore, in the context of associative memory, the functional connectivity between the HC and memory-related networks may be more important than the mere activation of specific regions. To investigate the specific contribution of the HC to associative memory, I examined the relationship between hippocampal resection and postoperative memory changes on various memory tests in patients who underwent surgery for medial temporal lobe epilepsy (MTLE). Through a voxel-based analysis that accounts for individual differences in the resection, it was found that resection of the HC was associated with a decline in associative memory rather than item memory. This finding emphasizes the specific involvement of the HC in associative memory processes. Expanding upon this understanding, I utilized single-trial EEG connectivity between the HC and neocortical regions to predict memory success and failure. The results achieved an average accuracy of over 90% in predicting subsequent memory performance. Notably, this level of accuracy was higher compared to utilizing brain activity in specific regions. In summary, this thesis highlights the significant role of the HC and its connectivity in associative memory. It underscores the significance of hippocampal communication with large-scale brain networks, rather than solely focusing on specific brain regions, in understanding memory processes.Abstract i Contents iii List of Figures v List of Tables vi List of Abbreviations vii I. INTRODUCTION 1 1.1 Associative Memory and the Hippocampus 1 1.2 Associative Memory beyond the MTL 5 1.2.1 Successful Memory Encoding and the Default Mode Network 5 1.2.2 Subsequent Memory Effects 9 1.3 Purpose of the Present Study 13 II. METHODS 14 2.1 Participants 14 2.1.1 Experiment 1. Medial Temporal Lobe Epilepsy Patients 14 2.1.2 Experiment 2. EEG Study Participants 18 2.2 Experimental Design 19 2.2.1 Experiment 1. Pre- and Post-operative Memory Test 19 2.2.2 Expereiment 2. EEG Experimental Paradigm 20 2.3 Data Analysis 22 2.3.1 Experiment 1. MRI Image and Statistical Analysis 22 2.3.2 Experiment 2. EEG Connectivity Analysis for Memory Performance Prediction 25 III. RESULTS 30 3.1 Experiment 1. Postoperative Memory Change Analysis Results 30 3.1.2 Neuropsychological Outcome 30 3.1.3 Voxel-based Analysis 32 3.2 Experiment 2. Memory Performance Prediction Results 35 3.2.1 Behavioral Results 35 3.2.2 Differences in Connectivity Features 35 3.2.3 Classification Accuracy 35 IV. DISCUSSION 40 4.1 Summary 40 4.2 Experiment 1. Associative Memory and Hippocampal Resection 41 4.3 Experiment 2. Prediction of Associative Memory Performance Using Hippocampal Connectivity 44 4.4 Conclusion 50 V. BIBLIOGRAPHY 51 Abstract in Korean 66박

The uneven profile of memory development in Down Syndrome

This thesis explores memory development in children with Down syndrome (DS) between aged 3 years and 9 months and 14 years and 5 months (N=43). While memory has been extensively explored in older individuals with DS, relatively little work has considered the development of memory in childhood in DS, in part due to the difficulty of assessing memory in individuals with lower levels of ability. The project was innovative in applying a mixture of original and pre-existing tasks to this population, in order to characterise a wide range of memory abilities at varying levels of cognitive demand. These abilities were initially compared between those with DS and typically developing individuals by age group, early childhood (3 years 9 months to 8 years 4 months) and late childhood (9 years 9 months to 14 years 5 months). Standardised tasks were used to produce mental-age equivalents and raw scores for verbal and non-verbal memory abilities (BPVS, BAS II pattern construction). Study 1 examined object and object-in-place recognition using eye-tracking, using a low demand methodology that excluded few participants. Study 2 examined verbal working and long-term memory abilities overall, as well as learning and forgetting rates. Primacy, recency and mid-list recall rates were also analysed to shed light on strategies of encoding. Study 3 examined spatial working and long-term memory abilities, as well as forgetting rates. Study 4 examined multimodal associative immediate and delayed memory, using a spatialauditory associative eye-tracking paradigm. Study 5 examined the relationships between sustained attention, inhibition, and sleep behaviour measures, as these faculties are implicated in the development of memory abilities. Finally, in Study 6, cross-sectional developmental trajectories were constructed for all memory measures to ascertain if base levels or gradients of change significantly differed, either with respect to chronological age or domain-relevant mental age measures, in comparison to a sample of typically developing children. Overall, the project charted the emergence of an uneven profile of memory abilities across childhood in DS

Effects of Prior Knowledge on Memory: Implications for Education

The encoding, consolidation, and retrieval of events and facts form the basis for acquiring new skills and knowledge. Prior knowledge can enhance those memory processes considerably and thus foster knowledge acquisition. But prior knowledge can also hinder knowledge acquisition, in particular when the to-be-learned information is inconsistent with the presuppositions of the learner. Therefore, taking students' prior knowledge into account and knowing about the way it affects memory processes is important for optimization of students' learning. Recent behavioral and neuroimaging experiments have shed new light on the neural mechanisms through which prior knowledge affects memory. However, relatively little is known about developmental differences in the ability to make efficient use of one's knowledge base for memory purposes. In this article, we review and integrate recent empirical evidence from developmental psychology and cognitive neuroscience about the effects of prior knowledge on memory processes. In particular, this may entail an extended shift from processing in the medial temporal lobes of the brain toward processing in the neocortex. Such findings have implications for students as developing individuals. Therefore, we highlight recent insights from cognitive neuroscience that call for further investigation in educational settings, discussing to what extent these novel insights may inform teaching in the classroom