Download or read book Functional Significance of the Neural Correlates of Episodic Retrieval written by Kaia Linn Vilberg and published by . This book was released on 2008 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Functional Significance of the Neural Correlates of Post retrieval Processing written by Hiroki Hayama and published by . This book was released on 2009 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Post-retrieval processes are engaged when the outcome of an episodic retrieval attempt must be monitored or evaluated. Previous research employing event-related potentials (ERPs) has implicated a specific ERP modulation - the 'right frontal old/new effect' - as a correlate of post-retrieval processing, whereas studies employing functional magnetic resonance imaging (fMRI) techniques have implicated right dorsolateral prefrontal cortex (DLPFC) as playing a role in these processes. Some recent studies, however, have suggested that the neural correlates of post-retrieval processing may have more to do with tracking the number of internal decisions required prior to response selection than with evaluating and monitoring the products of an episodic retrieval attempt. The aim of the present body of work was to characterize the functional significance of the right frontal old/new ERP effect and retrieval related activity in right DLPFC. The experiments described in Chapters 3, 4, and 5 were parallel ERP and fMRI investigations which aimed to determine whether the neural correlates of post-retrieval processing were specific to monitoring the episodic content of a retrieval attempt. In all three experiments it was found that the neural correlates of post-retrieval processing could be elicited by the evaluation and monitoring of semantic as well as episodic information. These findings are suggestive of a more domain-general post-retrieval processing role for the cognitive processes associated with these correlates. The final ERP experiment described in Chapter 6 sought to address the functional significance of the extended time-course of the right frontal old/new ERP effect. The findings from this experiment indicated that the right frontal effect persists well beyond the time of which a response is selected, implying that the effect reflects processes other than those engaged in service of response selection. Collectively, the findings support the proposal that the right frontal old/new ERP effect and retrieval related activity in right DLPFC reflect domain-general post-retrieval processes, and do not merely reflect number of internal decisions required prior to response selection.

Download or read book The Cognitive Neuroscience of Memory written by Amanda Parker and published by Psychology Press. This book was released on 2005-08-18 with total page 698 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in techniques available to memory researchers have led to a rapid expansion in the field of cognitive neuroscience of memory. This book provides accessible coverage of four key areas of recent advance, including research on functional imaging, electrophysiological and lesion studies, and developments from the computational modelling approach. The first section reviews functional imaging studies in humans, with particular emphasis on how imaging methods have clarified the cortical areas involved in memory formation and retrieval. The second section describes electrophysiological and lesion research in monkeys, where lesion and disconnection studies are rapidly adding to our knowledge of both information processing and modulatory aspects of memory formation. In the third section, electrophysiological and lesion studies in rats are reviewed allowing for a detailed study of the role of novelty and exploration in memory formation. The final section reviews current research in computational modelling which has allowed the development of new theoretical and experimental approaches to the study of memory encoding and retrieval. This volume draws together the current developments in each field, allowing the synthesis of ideas and providing converging evidence from a range of sources. It will be a useful resource for both advanced undergraduate and postgraduate students of psychology, as well as researchers in the field and anyone with an interest in cognitive neuroscience.

Download or read book Functional Significance of Neural Correlates of Episodic Encoding written by Melina Rifka Uncapher and published by . This book was released on 2007 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Neural Mechanisms of Real World Episodic Memory Retrieval Investigations Using Functional Neuroimaging Brain Stimulation and Wearable Camera Technology written by Tiffany Chow and published by . This book was released on 2017 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advancements in neuroimaging and brain stimulation techniques have provided unique opportunities to further understand the neural mechanisms of episodic memory retrieval. The act of retrieving information about a past experience is known to depend on the coordinated engagement of a broad networks of regions, including frontal lobe regions such as the rostrolateral prefrontal cortex (RLPFC) and medial temporal lobe areas such as the hippocampus (Cabeza & St. Jacques, 2007; Maguire & Mummery, 1999; Reynolds, McDermott, & Braver, 2006). Although much of the field's extant knowledge has been derived from studies assessing memories formed in laboratory-based settings, the incorporation of life-logging technology - such as wearable digital camera devices - can assist with the nonintrusive photographic capture of everyday life events, which can later be employed as mnemonic probes. The experiments in this dissertation aim to assess the neural mechanisms mediating real-world episodic retrieval by employing naturalistic stimuli to elicit memories for personal experiences. This dissertation begins with a broad overview of the behavioral and neural findings derived from memory experiments incorporating wearable camera technology, followed by novel examinations of the neural correlates underlying real-world events through the use of functional magnetic resonance imaging (fMRI) and high-definition transcranial direct current stimulation (HD-tDCS). Chapter 2 featured an in-depth review of prior applications of wearable digital cameras to behavioral and neuroimaging assessments of autobiographical memory retrieval as well as how their contributions expand knowledge of such processes to naturalistic settings. Chapters 3-5 report the results of a series of fMRI investigations examining recall of events from the real world and how they may differ across mnemonic features related to the original experiential source of the event, the recognition of the event based on previously encountering photographs of those experiences, and the temporal order of the event details. Chapter 3 found that dissociable patterns of neural activation were evoked in brain networks previously implicated in either autobiographical or laboratory-based memory retrieval (McDermott, Szpunar, & Christ, 2009), such that the autobiographical memory network was preferentially sensitive to whether or not the depicted events had been personally experienced, while the laboratory-based network was preferentially sensitive to whether or not photographs of the depicted events had been previously encountered. These findings suggest that these networks contribute to different retrieval processes and showcase how memories for first-hand experiences have distinctive neural signatures from memories for second-hand event knowledge. Chapter 4 focused on the hippocampus, with an emphasis on the division of labor along the hippocampal long-axis. The findings revealed that the posterior hippocampus was disproportionately sensitive to the source of the photographs, whereas the anterior hippocampus reacted more strongly to whether the photographs themselves had been previously seen, as well as whether their temporal order was intact. Chapter 5 assessed hemispheric differences in RLPFC responsivity to violations of temporal order during retrieval. The left RLPFC exhibited greater activation for temporal order violations only when events were novel, while the right RLPFC demonstrated greater activation for temporal order violations only when events had been previously encountered as photographs. These results suggest that the RLPFC is capable of differentially determining whether events are consistent with either prior schemas or memories. To further examine the left RLPFC and evaluate its causal involvement in mnemonic processes, Chapter 6 applied HD-tDCS methodology to this region in order to determine its impact on event recognition and temporal order processing. The targeted application of anodal current to the left RLPFC produced an increased likelihood of false recognition and - relative to sham stimulation - led to a shift in response bias, which may indicate the RLPFC's role in memory monitoring. Together, these findings from fMRI and HD-tDCS experiments help clarify the contributions and characteristics of the neural substrate supporting episodic memory retrieval, particularly with regards to how these processes may occur in the real world.

Download or read book An Investigation of Continuous and Discontinuous Memory Signals Supporting Episodic Memory Retrieval written by Sarah Yu and published by . This book was released on 2013 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: This body of research investigates the neural correlates of recollection- and familiarity-driven recognition memory using functional neuroimaging (fMRI), electrophysiological (EEG and ERP), and behavioral methods. In particular, the aim of the present body of work was to characterize the functional significance of familiarity and recollection, and investigate whether the neural correlates underlying these signals are thresholded or continuous. The ERP experiment in Chapter 2 found that the ERP correlate of familiarity is modulated as a function of the strength of the familiarity signal. Furthermore, this experiment found functionally, topographically, and temporally dissociable ERP correlates of recollection and familiarity, suggesting that these processes are themselves distinct. The experiments in Chapters 3-4 identified and characterized the fMRI correlates of recollection in the hippocampus and left lateral parietal cortex, respectively. We found that activity in the hippocampus tracked the amount of contextual information recollected and not memory strength. In the lateral parietal cortex, we found that angular gyrus activity tracked the amount of recollected information, whereas activity in the temporo-parietal junction (TPJ) was enhanced for items endorsed as recollected, but insensitive to the amount of information recollected. The high-resolution fMRI experiment in Chapter 5 extended our findings in the hippocampus and angular gyrus, and investigated the response profiles of other members of the 'recollection-sensitive' network with respect to amount of contextual information recollected. Together, the findings in Chapters 3-5 demonstrated that the members of the recollection network exhibit different response profiles with respect to amount of information recollected, suggesting that members of this network may play different roles in supporting contextual recollection. Collectively, the findings in this body of work support the notion that familiarity and recollection are distinct recognition processes. Furthermore, each of these processes positively tracks the confidence with which they are endorsed.

Download or read book Investigations of Age related Effects on the Neural Correlates of Recollection and Familiarity written by Tracy Hsiang-Yi Wang and published by . This book was released on 2013 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present research investigated age-related differences in the neural correlates of two putative processes (recollection and familiarity) supporting recognition memory. Functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) were utilized in concert with retrieval tasks that allow trials associated with recollection to be segregated from trials associated with familiarity. Some studies investigating age-related effects on the neural correlates of successful retrieval have reported that the neural correlates of retrieval are larger and more widespread in older subjects than in the young ('cortical over-recruitment'). These studies, however, vary widely in their methodologies, analyses, and even characterization of memory retrieval. The aim of the research described here is to elucidate the effects of age on the neural correlates of recognition memory. The second chapter of this dissertation describes an experiment that characterizes the neural correlates of episodic memory in subjects typically considered 'older' (between the ages of 63-77) and 'younger' (between the ages of 18-30) as indexed by functional magnetic resonance imaging (fMRI). The third chapter describes an analogous Event-related potential (ERP) study that investigated the electrophysiological correlates of recollection and familiarity in the same age groups as the study described in the second chapter. Finally, the fourth chapter describes the final experiment that investigated cortical reinstatement of material-specific recollection related effects in young and older subjects. This final study utilized univariate analysis to identify cortical reinstatement of material specific recollection-related activity, while using multivariate pattern analysis to quantify the amount of reinstatement in each age group. Overall, the findings provide evidence that there is no significant neural reorganization for the retrieval of episodic memory in the face of advancing age. Rather, the presented research suggests that under circumstances where encoding and retrieval are well controlled, the neural correlates of episodic retrieval remain largely invariant as a function of age.

Download or read book The Wiley Handbook on The Cognitive Neuroscience of Memory written by Donna Rose Addis and published by John Wiley & Sons. This book was released on 2015-06-02 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Wiley Handbook on the Cognitive Neuroscience of Memory presents a comprehensive overview of the latest, cutting-edge neuroscience research being done relating to the study of human memory and cognition. Features the analysis of original data using cutting edge methods in cognitive neuroscience research Presents a conceptually accessible discussion of human memory research Includes contributions from authors that represent a “who’s who” of human memory neuroscientists from the U.S. and abroad Supplemented with a variety of excellent and accessible diagrams to enhance comprehension

Download or read book The Neural Correlates of Recollection and Post retrieval Monitoring in Younger and Older Adults written by Erin D. Horne and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Episodic retrieval is not a homogeneous process, but rather involves the engagement of several dissociable cognitive processes. These processes include those specialized for memory functions, such as hippocampally mediated pattern completion processes, as well as generic cognitive control processes linked with activity in the frontal cortex. Thus, age-related decline in episodic memory performance is not consistent across all aspects of retrieval, but dissociable subprocesses contributing to successful retrieval are affected to differing extents. To examine agerelated differences in processes contributing to retrieval, we investigated the neural correlates of recollection and post-retrieval monitoring in samples of younger and older adults using ERP (experiment 1: Ns 20 per group) and fMRI (experiment 2: Ns 28 per group). In experiment 1, we focused on modulation of recollection-related activity (operationalized as subjective report using the RKN procedure) as a function of source accuracy. In experiment 2, we examined how varying the global task demand of an associative recognition task by adding a secondary tone detection task might modulate prefrontal monitoring effects in younger and older adults. Across experiments, we found that both age groups activated a common set of regions supporting memory retrieval (in most cases), but that older adults demonstrated less modulation of recollection- and monitoring-related activity. This finding suggests that a breakdown in the ability to dynamically modulate activity supporting retrieval according to online task demands may be a key factor underlying the decline in memory performance with advancing age.

Download or read book Progress in Episodic Memory Research written by Ekrem Dere and published by Frontiers Media SA. This book was released on 2016-05-25 with total page 515 pages. Available in PDF, EPUB and Kindle. Book excerpt: Episodic memory refers to the ability to remember personal experiences in terms of what happened and where and when it happened. Humans are also able to remember the specific perceptions, emotions and thoughts they had during a particular experience. This highly sophisticated and unique memory system is extremely sensitive to cerebral aging, neurodegenerative and neuropsychiatric diseases. The field of episodic memory research is a continuously expanding and fascinating area that unites a broad spectrum of scientists who represent a variety of research disciplines including neurobiology, medicine, psychology and philosophy. Nevertheless, important questions still remain to be addressed. This research topic on the Progress in Episodic Memory Research covers past and current directions in research dedicated to the neurobiology, neuropathology, development, measurement and treatment of episodic memory.

Download or read book The Functional Neuroanatomy of Episodic Retrieval written by James E. Kragel and published by . This book was released on 2015 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Reward and Decision Making written by Jean-Claude Dreher and published by Academic Press. This book was released on 2009-06-04 with total page 527 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses a fundamental question about the nature of behavior: how does the brain process reward and makes decisions when facing multiple options? The book presents the most recent and compelling lesion, neuroimaging, electrophysiological and computational studies, in combination with hormonal and genetic studies, which have led to a clearer understanding of neural mechanisms behind reward and decision making. The neural bases of reward and decision making processes are of great interest to scientists because of the fundamental role of reward in a number of behavioral processes (such as motivation, learning and cognition) and because of their theoretical and clinical implications for understanding dysfunctions of the dopaminergic system in several neurological and psychiatric disorders (schizophrenia, Parkinson's disease, drug addiction, pathological gambling, ...) - Comprehensive coverage of approaches to studying reward and decision making, including primate neurophysiology and brain imaging studies in healthy humans and in various disorders, genetic and hormonal influences on the reward system and computational models. - Covers clinical implications of process dysfunction (e.g., schizophrenia, Parkinson's disease, eating disorders, drug addiction, pathological gambling) - Uses multiple levels of analysis, from molecular mechanisms to neural systems dynamics and computational models. " This is a very interesting and authoritative handbook by some of the most outstanding investigators in the field of reward and decision making ", Professor Edmund T. Rolls, Oxford Center for Computational Neuroscience, UK

Download or read book Electrophysiology of Mind written by Michael D. Rugg and published by . This book was released on 1995 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews a productive period of research aimed at connecting brain and mind through the use of scalp-recorded brain potentials to chart the temporal course of information processing in the human brain. The book serves as both as a summary of where we have been and as a pointer of the way ahead.

Download or read book Cognitive and Neural Correlates of Memory Retrieval in Young and Older Adults written by Gail O'Kane and published by . This book was released on 2004 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) increased activity whenever recollection was attempted, independent of the level of recollection success. The results are consistent with the hypothesis that increased left-lateralized retrieval activity in older adults supports recollection attempt. Age deficits in semantic memory are more subtle than in episodic memory. However, older adults are impaired when automatic, data-driven processes are not sufficient to support the retrieval of conceptual knowledge. The fMRI study described in Chapter 3 used semantic repetition priming to test two theories of the role LIPC plays in semantic retrieval. Young adults exhibited repetition-related BOLD response reductions in LIPC that were specific to the particular semantic task engaged, consistent with the hypothesis that LIPC supports controlled semantic retrieval. Older adults, in contrast, exhibited repetition-related signal reductions even when the semantic judgment made about a word differed across the two exposures, consistent with the hypothesis that older adults fail to gate irrelevant semantic information from working memory during initial presentation of the word.

Download or read book Predictions in the Brain written by Moshe Bar and published by Oxford University Press. This book was released on 2011-05-10 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: When one is immersed in the fascinating world of neuroscience findings, the brain might start to seem like a collection of "modules," each specializes in a specific mental feat. But just like in other domains of Nature, it is possible that much of the brain and mind's operation can be explained with a small set of universal principles. Given exciting recent developments in theory, empirical findings and computational studies, it seems that the generation of predictions might be one strong candidate for such a universal principle. This is the focus of Predictions in the brain. From the predictions required when a rat navigates a maze to food-caching in scrub-jays; from predictions essential in decision-making to social interactions; from predictions in the retina to the prefrontal cortex; and from predictions in early development to foresight in non-humans. The perspectives represented in this collection span a spectrum from the cellular underpinnings to the computational principles underlying future-related mental processes, and from systems neuroscience to cognition and emotion. In spite of this diversity, they share some core elements. Memory, for instance, is critical in any framework that explains predictions. In asking "what is next?" our brains have to refer to memory and experience on the way to simulating our mental future. But as much as this collection offers answers to important questions, it raises and emphasizes outstanding ones. How are experiences coded optimally to afford using them for predictions? How do we construct a new simulation from separate memories? How specific in detail are future-oriented thoughts, and when do they rely on imagery, concepts or language? Therefore, in addition to presenting the state-of-the-art of research and ideas about predictions as a universal principle in mind and brain, it is hoped that this collection will stimulate important new research into the foundations of our mental lives.

Download or read book Content Reinstatement and Source Confidence During Episodic Memory Retrieval written by Emily K. Leiker and published by . This book was released on 2014 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: Episodic retrieval is the process of bringing information about a past experience from memory into conscious awareness. Variation in the retrieval process, in regard to content and quality of the information retrieved, is believed to rely on the reactivation of neural patterns of activity elicited during the original experience -- a process called neural reinstatement. Research in support of this idea has relied on participant reports of retrieval quality, but not content, to assess variation in retrieval. Without measuring the content of retrieval, it is unclear whether reinstatement underlies retrieval per se, or merely the evaluation of retrieval quality. The current study addressed this issue by examining the relationship between the magnitude of neural reinstatement during retrieval, and a direct behavioral measure of both retrieval content and quality. Participants viewed a series of words in the context of three encoding tasks, and then completed a memory test on a series of words in which they first identified the encoding task completed for a given word, and next rated their confidence in that decision. Pattern classification analyses were performed on fMRI data acquired during encoding and retrieval phases to index reinstatement, and reinstatement effects were examined according to the behavioral and neural correlates of source confidence. The findings support a relationship between reinstatement and variation in the content and quality of retrieval, and also suggest a role for regions such as left posterior parietal cortex in monitoring reinstated activity to guide decisions about retrieval quality.

Download or read book The Role of the Prefrontal Cortex in Episodic Memory Pet Studies in Normal Subjects written by Shitij Kapur and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis documents the findings of a series of positron emission tomography (PET) experiments undertaken to eluicidate the neural correlates of episodic memory--in particular, to understand the functional contributions of the prefrontal cortex to episodic memory. Healthy young adults were scanned using ($\sp#x15;$O) -H$\sb2$O-PET imaging as they carried out encoding and retrieval tasks. The data were analyzed using the cognitive subtraction paradigm and Statistical Parametric Mapping technique of image analysis. The results clearly document a differential involvement of the left and right prefrontal cortex in encoding and retrieval respectively. The thesis further suggests that the left prefrontal activation is invoked by the task requirement of "working with meaning" of the stimulus. The results are supportive of a role for the left prefrontal cortex in facilitating the formation of a retrievable engram, regardless of the subject's intention. The right prefrontal cortex is invoked equally in recall and recognition tasks when these tasks are equated for difficulty. The role of the right prefrontal cortex in retrieval as revealed by PET, is consistent with the concept of "retrieval attempt" and is distinguishable for the concept of "ecphory" which may be a medial temporal or posterior association cortex based process. The results are discussed in concert with neuropsychological findings and it is concluded that the prefrontal cortex facilitates memory encoding and retrieval processes--though it may not be the site where the engram resides. The discrepancy with established neuropsychological findings is discussed and directions for future research are outlined.