[PDF] The Fidelity Of Neural Representations Shapes Episodic Memory Across The Human Lifespan eBook

Author : Peter Graf (PhD.)
Publisher : MIT Press
Page : 322 pages
File Size : 38,78 MB
Release : 2002
Category : Medical
ISBN : 9780262072366

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An original approach to memory development that views memory as a continuous process of growth and loss over the human lifespan rather than as a series of separate periods. Until recently, the vast majority of memory research used only university students and other young adults as subjects. Although such research successfully introduced new methodologies and theoretical concepts, it created a bias in our understanding of the lifespan development of memory. This book signals a departure from young-adult-centered research. It views the lifespan development of memory as a continuous process of growth and loss, where each phase of development raises unique questions favoring distinct research methods and theoretical approaches. Drawing on a broad range of investigative strategies, the book lays the foundation for a comprehensive understanding of the lifespan development of human memory. Topics include the childhood and adulthood development of working memory, episodic and autobiographical memory, and prospective memory, as well as the breakdown of memory functions in Alzheimer's disease. Of particular interest is the rich diversity of approaches, methods, and theories. The book takes an interdisciplinary perspective, drawing on work from psychology, psychiatry, gerontology, and biochemistry.

Author : Elisabeth A. Murray
Publisher : Oxford University Press
Page : 644 pages
File Size : 27,34 MB
Release : 2016-11-10
Category : Psychology
ISBN : 0191509965

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Current theories about human memory have been shaped by clinical observations and animal experiments. This doctrine holds that the medial temporal lobe subserves one memory system for explicit or declarative memories, while the basal ganglia subserves a separate memory system for implicit or procedural memories, including habits. Cortical areas outside the medial temporal lobe are said to function in perception, motor control, attention, or other aspects of executive function, but not in memory. 'The Evolution of Memory Systems' advances dramatically different ideas on all counts. It proposes that several memory systems arose during evolution and that they did so for the same general reason: to transcend problems and exploit opportunities encountered by specific ancestors at particular times and places in the distant past. Instead of classifying cortical areas in terms of mutually exclusive perception, executive, or memory functions, the authors show that all cortical areas contribute to memory and that they do so in their own ways-using specialized neural representations. The book also presents a proposal on the evolution of explicit memory. According to this idea, explicit (declarative) memory depends on interactions between a phylogenetically ancient navigation system and a representational system that evolved in humans to represent one's self and others. As a result, people embed representations of themselves into the events they experience and the facts they learn, which leads to the perception of participating in events and knowing facts. 'The Evolution of Memory Systems' is an important new work for students and researchers in neuroscience, psychology, and biology.

Author : Ellen Bialystok
Publisher : Oxford University Press, USA
Page : 434 pages
File Size : 27,50 MB
Release : 2006
Category : Psychology
ISBN : 9780195169539

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Aims to create a bridge across cognitive development and cognitive aging. This volume studies the rise and fall of specific cognitive functions, such as attention, executive functioning, memory, working memory, representations, and individual differences to find ways in which the study of development and decline converge on common mechanisms.

Author : Elizabeth Ankudowich
Publisher :
Page : pages
File Size : 31,44 MB
Release : 2018
Category :
ISBN :

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"Episodic memory encompasses an extraordinary range of diverse cognitive functions that are integral to daily functioning. Healthy aging is associated with declines in episodic memory, which may impair older adults' ability to remember the rich contextual details of previously experienced events. By the age of sixty, older individuals may have a reduced ability to remember spatial or temporal contextual features of past events (e.g., where or when you last took a prescription medication). Previous studies have focused on understanding the anatomical and functional neural correlates of episodic memory decline in young and older adulthood, but how these underlying mechanisms contribute to episodic memory to across the adult lifespan remains to be explored. In this series of studies, we aim to advance our understanding of the differences in episodic memory that develop across the adult lifespan and the neural basis of this age-related decline, as measured by functional magnetic resonance imaging (fMRI). Using a lifespan sample of young, middle-aged, and older adults, we employ a source memory paradigm to assess individuals' memory for the spatial and temporal contextual details of photographs of faces. In addition, we analyze fMRI data collected during both initial encoding and subsequent retrieval of contextual information in order to examine differential effects of age on encoding- and retrieval-specific processes. In Study 1, we demonstrate that declines in source memory may be discernible by midlife, extend into older adulthood, and are associated with reduced modulation of phase-specific activity in anterior prefrontal (PFC) and posterior ventral visual areas. We also show that older adulthood may be associated with increased phase-specific modulation, particularly in areas of lateral PFC and medial temporal lobes (MTL) at retrieval. In Study 2, we extend these findings to show how lifespan differences in phase-specific activity directly contribute to source memory performance. In particular, we find that older individuals engage dorsolateral PFC (DLPFC) to a greater extent at encoding and hippocampus (HC) to a greater extent at retrieval, during the phase when it does not seem to help performance across individuals. In Study 3, we address whether these age-related increases in encoding- or retrieval-specific activation might be related to differences in whole-brain connectivity. We examine whether age-related increases in DLPFC (Study 2 encoding) and posterior HC (Study 2 retrieval) differentially correlate with activity across the rest of the brain and with performance. In young adults, we demonstrate that connectivity between lateral PFC, parietal, and ventral visual cortical regions and our DLPFC seed relates to better performance. In older adults, these same regions show greater connectivity with posterior HC and relate to worse performance. Converging findings across studies suggests that activity and connectivity among fronto-parietal regions support the recollection of visual information and source memory performance in young adults, whereas aging may be associated with altered modulation of fronto-parietal activity and connectivity with posterior HC, which does not support source memory performance." --

Author : Amber Schedlbauer
Publisher :
Page : pages
File Size : 16,50 MB
Release : 2017
Category :
ISBN : 9780355764376

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Spatial and temporal details constitute critical components of our memories for recently experienced events, termed episodic memories. Both knowledge about where we were and approximately when things happened during our day are important cues for remembering what happened to us at an earlier event. A region called the hippocampus has been strongly implicated in the forming and retrieving of these episodic memories. However, the relative importance of cortical areas in conjunction with the hippocampus to episodic memory remains under debate. Specifically, a vast majority of the studies have focused only on characterizing the individual contributions of the hippocampus or specific cortical modules to episodic memory rather than determining the interactions among them. With the studies conducted here, I have represented episodic mnemonic processes as large-scale networks derived from functional connectivity analyses applied to human neuroimaging and electrophysiology data. By applying quantitative measures from the field of graph theory, I aim to provide insight into the global and local organization of coordinated interactions between regions throughout the brain. I hypothesize that network analyses will demonstrate that different aspects of episodic memory, including encoding and retrieval, will produce specific network representations. Furthermore, the large-scale functional network organization will vary based upon the type of information being processed and during directed cognition as compared to rest. First, I provide an overview of past research dedicated to understanding the neural basis of memory processes through networks. Next, I present a neuroimaging study evaluating the unique networks present during successful and unsuccessful retrieval and during spatiotemporal processing. Increases in overall network connectivity exemplified successful retrieval with density correlating with retrieval accuracy. Furthermore, I identified distinct but overlapping subnetworks for spatial and temporal retrieval with the hippocampus and additional neocortical regions as hubs of connectivity within the networks. In a second neuroimaging experiment, I again established separate spatiotemporal networks and applied a data-driven approach to characterize connectivity patterns involved in the encoding and retrieval of contextual information. A comparison of task-based with resting-state partitions showed that data-driven models capture variance in memory performance and supply a parsimonious view of network topology. Finally, in an electrophysiology study, we disrupted network connectivity (and possibly communication) by directly stimulating specific areas in order to provide evidence for the utility and accuracy of network representations. Specifically, we targeted the spatial retrieval network and produced a deficit in spatial but not temporal retrieval performance. Thus, network models are a new avenue of research into the brain-wide interactions thought to represent relevant mnemonic processes and can be leveraged to gain insight into brain-behavior relationships.

Author : Neal J. Cohen
Publisher : MIT Press
Page : 1182 pages
File Size : 31,94 MB
Release : 1993
Category : Medical
ISBN : 9780262531320

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In this sweeping synthesis, Neal J. Cohen and Howard Eichenbaum bring together converging findings from neuropsychology, neuroscience, and cognitive science that provide the critical clues and constraints for developing a more comprehensive understanding of memory. Specifically, they offer a cognitive neuroscience theory of memory that accounts for the nature of memory impairment exhibited in human amnesia and animal models of amnesia, that specifies the functional role played by the hippocampal system in memory, and that provides further understanding of the componential structure of memory.The authors' central thesis is that the hippocampal system mediates a capacity for declarative memory, the kind of memory that in humans supports conscious recollection and the explicit and flexible expression of memories. They argue that this capacity emerges from a representation of critical relations among items in memory, and that such a relational representation supports the ability to make inferences and generalizations from memory, and to manipulate and flexibly express memory in countless ways. In articulating such a description of the fundamental nature of declarative representation and of the mnemonic capabilities to which it gives rise, the authors' theory constitutes a major extension and elaboration of the earlier procedural-declarative account of memory.Support for this view is taken from a variety of experimental studies of amnesia in humans, nonhuman primates, and rodents. Additional support is drawn from observations concerning the neuroanatomy and neurophysiology of the hippocampal system. The data taken from divergent literatures are shown to converge on the central theme of hippocampal involvement in declarative memory across species and across behavioral paradigms.

Author : Jin-Hui Wang
Publisher : Springer Nature
Page : 275 pages
File Size : 27,81 MB
Release : 2019-09-10
Category : Medical
ISBN : 9811395012

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This book focuses on associative memory cells and their working principles, which can be applied to associative memories and memory-relevant cognitions. Providing comprehensive diagrams, it presents the author's personal perspectives on pathology and therapeutic strategies for memory deficits in patients suffering from neurological diseases and psychiatric disorders. Associative learning is a common approach to acquire multiple associated signals, including knowledge, experiences and skills from natural environments or social interaction. The identification of the cellular and molecular mechanisms underlying associative memory is important in furthering our understanding of the principles of memory formation and memory-relevant behaviors as well as in developing therapeutic strategies that enhance memory capacity in healthy individuals and improve memory deficit in patients suffering from neurological disease and psychiatric disorders. Although a series of hypotheses about neural substrates for associative memory has been proposed, numerous questions still need to be addressed, especially the basic units and their working principle in engrams and circuits specific for various memory patterns. This book summarizes the developments concerning associative memory cells reported in current and past literature, providing a valuable overview of the field for neuroscientists, psychologists and students.