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Oliver T Wolf - One of the best experts on this subject based on the ideXlab platform.
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Stress and Memory Retrieval: mechanisms and consequences
Current Opinion in Behavioral Sciences, 2017Co-Authors: Oliver T WolfAbstract:Stress impairs Memory Retrieval. Recent findings illustrate the temporal dynamics and the underlying mechanisms of this effect. The effect appears to occur in multiple Memory systems, ranging from striatal-based stimulus-response Memory to prefrontal-based extinction Memory. The effects of stress on Memory Retrieval might have long-term consequences due to their impact on re-encoding and re-consolidation. These properties could be of interest for future intervention studies.
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Cortisol effects on autobiographic Memory Retrieval in PTSD: an analysis of word valence and time until Retrieval.
Stress (Amsterdam Netherlands), 2013Co-Authors: Katja Wingenfeld, Martin Driessen, Kirsten Terfehr, Nicole Schlosser, Silvia Carvalho Fernando, Oliver T WolfAbstract:AbstractIn healthy participants, cortisol administration has been found to impair autobiographic Memory Retrieval. We recently reported that administration of 10 mg of hydrocortisone had enhancing effects on autobiographical Memory Retrieval, i.e. more specific Memory Retrieval, in patients with posttraumatic stress disorder (PTSD), while in healthy controls the impairing effects were replicated. We here report a re-analysis of these data with respect to cue-word valence and Retrieval time. In a placebo-controlled cross-over study, 43 patients with PTSD and 43 age- and sex-matched healthy controls received either placebo or hydrocortisone orally before the autobiographical Memory test was performed. We found that the effects of cortisol on Memory Retrieval depended on cue-word valence and group (significant interaction effects of drug by group and drug by valence by group). The enhancing effect of cortisol on Memory Retrieval in PTSD seemed to be relatively independent of cue-word valence, while in the co...
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Stress disrupts response Memory Retrieval.
Psychoneuroendocrinology, 2013Co-Authors: Friederike M. Guenzel, Oliver T Wolf, Lars SchwabeAbstract:Summary Stress effects on Memory are well-known. Most studies, however, focused on the impact of stress on hippocampus-dependent ‘declarative’ Memory processes. Less is known about whether stress influences also striatum-based Memory processes, such as stimulus–response (S–R) Memory. First evidence from rodent experiments shows that glucocorticoid stress hormones may enhance the consolidation of S–R memories. Whether stress affects also S–R Memory Retrieval remains largely elusive. Therefore, we tested in the present experiment in humans the effect of stress on the Retrieval of S–R memories. Healthy men and women were trained to locate three objects in an S–R version of a virtual eight-arm radial maze. One week later, participants underwent a stressor or a control condition before their Memory of the S–R task was tested. Our results showed that participants ( n = 43) who were exposed to the stressor before retention testing made significantly more errors in this test trial, suggesting that stress impaired S–R Memory Retrieval. Moreover, high cortisol concentrations were associated with reduced S–R Memory. These findings indicate that stress may affect Memory Retrieval processes in humans beyond hippocampal ‘declarative’ Memory.
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Cortisol has enhancing, rather than impairing effects on Memory Retrieval in PTSD.
Psychoneuroendocrinology, 2011Co-Authors: Katja Wingenfeld, Martin Driessen, Kirsten Terfehr, Nicole Schlosser, Silvia Carvalho Fernando, Christian Otte, Thomas Beblo, Carsten Spitzer, Bernd Löwe, Oliver T WolfAbstract:Summary Background In the present study, we aimed to compare the effect of exogenous cortisol on Memory Retrieval in posttraumatic stress disorder (PTSD) with the effects in healthy controls. In healthy participants, administration of cortisol impairs declarative Memory Retrieval. Only a few studies have investigated these effects in PTSD yielding mixed results. Methods In a placebo-controlled crossover study, 44 patients with PTSD and 65 healthy controls received either placebo or 10 mg of hydrocortisone orally before Memory testing. In addition to declarative Memory Retrieval (word list learning), we also tested autobiographical Memory Retrieval specificity. Results In both tasks opposing effects of cortisol on Memory were observed when comparing patients with controls. In controls, cortisol had impairing effects on Memory Retrieval, while in PTSD patients cortisol had enhancing effects on Memory Retrieval in both Memory domains. Conclusions The present results suggest beneficial effects of acute cortisol elevations on hippocampal mediated Memory processes in PTSD. Possible neurobiological mechanisms underlying these findings are discussed.
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Psychosocial stress exposure impairs Memory Retrieval in children.
Psychoneuroendocrinology, 2011Co-Authors: A.a. Quesada, Uta S. Wiemers, Daniela Schoofs, Oliver T WolfAbstract:Negative consequences of stress on working Memory and delayed Memory Retrieval have been observed in adult humans. Little is known about the occurrence of similar effects in children. Forty-four German full-term children, aged 8-10 years, were randomly assigned to a stressful (Trier Social Stress Test for Children--TSST-C) or to a non-stressful control condition. Afterwards, delayed Memory Retrieval was tested using a computerized version of the well-known card game "Memory". It contained positive, neutral and negative stimuli. In addition, working Memory of verbal and non-verbal material was assessed. The stressed children showed pronounced cortisol increases accompanied by a decrease in mood. Children exposed to the stressor performed poorer in the delayed Memory Retrieval test (Memory card game). They committed more errors. No differences were found for working Memory. The stress-induced Memory Retrieval impairment mirrors findings in adults. In contrast, the missing working Memory effects could suggest developmental differences in stress sensitivity.
Liqun Luo - One of the best experts on this subject based on the ideXlab platform.
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Temporal evolution of cortical ensembles promoting remote Memory Retrieval
Nature neuroscience, 2019Co-Authors: Laura A. Denardo, Cindy D. Liu, William E. Allen, Eliza L. Adams, Drew Friedmann, Casey J. Guenthner, Marc Tessier-lavigne, Liqun LuoAbstract:Memories of fearful events can last a lifetime. The prelimbic (PL) cortex, a subregion of prefrontal cortex, plays a critical role in fear Memory Retrieval over time. Most studies have focused on acquisition, consolidation, and Retrieval of recent memories, but much less is known about the neural mechanisms of remote Memory. Using a new knock-in mouse for activity-dependent genetic labeling (TRAP2), we demonstrate that neuronal ensembles in the PL cortex are dynamic. PL neurons TRAPed during later Memory Retrievals are more likely to be reactivated and make larger behavioral contributions to remote Memory Retrieval compared to those TRAPed during learning or early Memory Retrieval. PL activity during learning is required to initiate this time-dependent reorganization in PL ensembles underlying Memory Retrieval. Finally, while neurons TRAPed during earlier and later Retrievals have similar broad projections throughout the brain, PL neurons TRAPed later have a stronger functional recruitment of cortical targets.
Laura A. Denardo - One of the best experts on this subject based on the ideXlab platform.
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Temporal evolution of cortical ensembles promoting remote Memory Retrieval
Nature neuroscience, 2019Co-Authors: Laura A. Denardo, Cindy D. Liu, William E. Allen, Eliza L. Adams, Drew Friedmann, Casey J. Guenthner, Marc Tessier-lavigne, Liqun LuoAbstract:Memories of fearful events can last a lifetime. The prelimbic (PL) cortex, a subregion of prefrontal cortex, plays a critical role in fear Memory Retrieval over time. Most studies have focused on acquisition, consolidation, and Retrieval of recent memories, but much less is known about the neural mechanisms of remote Memory. Using a new knock-in mouse for activity-dependent genetic labeling (TRAP2), we demonstrate that neuronal ensembles in the PL cortex are dynamic. PL neurons TRAPed during later Memory Retrievals are more likely to be reactivated and make larger behavioral contributions to remote Memory Retrieval compared to those TRAPed during learning or early Memory Retrieval. PL activity during learning is required to initiate this time-dependent reorganization in PL ensembles underlying Memory Retrieval. Finally, while neurons TRAPed during earlier and later Retrievals have similar broad projections throughout the brain, PL neurons TRAPed later have a stronger functional recruitment of cortical targets.
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Temporal Evolution of Cortical Ensembles Promoting Remote Memory Retrieval
2018Co-Authors: Laura A. Denardo, Cindy D. Liu, William E. Allen, Eliza L. Adams, Drew Friedmann, Casey J. Guenthner, Ehsan Dadgar-kiani, Jin Hyung Lee, Marc Tessier-lavigneAbstract:Studies of amnesic patients and animal models support a systems consolidation model, which posits that explicit memories formed in hippocampus are transferred to cortex over time1-6. Prelimbic cortex (PL), a subregion of the medial prefrontal cortex, is required for the expression of learned fear memories from hours after learning until weeks later7-12. While some studies suggested that prefrontal cortical neurons active during learning are required for Memory Retrieval13-15, others provided evidence for ongoing cortical circuit reorganization during Memory consolidation10,16,17. It has been difficult to causally relate the activity of cortical neurons during learning or recent Memory Retrieval to their function in remote Memory, in part due to a lack of tools18. Here we show that a new version of 9targeted recombination in active populations9, TRAP2, has enhanced efficiency over the past version, providing brain-wide access to neurons activated by a particular experience. Using TRAP2, we accessed PL neurons activated during fear conditioning or 1-, 7-, or 14-day Memory Retrieval, and assessed their contributions to 28-day remote Memory. We found that PL neurons TRAPed at later Retrieval times were more likely to be reactivated during remote Memory Retrieval, and more effectively promoted remote Memory Retrieval. Furthermore, reducing PL activity during learning blunted the ability of TRAPed PL neurons to promote remote Memory Retrieval. Finally, a series of whole-brain analyses identified a set of cortical regions that were densely innervated by Memory-TRAPed PL neurons and preferentially activated by PL neurons TRAPed during 14-day Retrieval, and whose activity co-varied with PL and correlated with Memory specificity. These findings support a model in which PL ensembles underlying remote Memory undergo dynamic changes during the first two weeks after learning, which manifest as increased functional recruitment of cortical targets.
Michael H. Buonocore - One of the best experts on this subject based on the ideXlab platform.
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Remembering familiar people: the posterior cingulate cortex and autobiographical Memory Retrieval.
Neuroscience, 2001Co-Authors: Richard J. Maddock, Amy Garrett, Michael H. BuonocoreAbstract:Most functional imaging studies of Memory Retrieval investigate Memory for standardized laboratory stimuli. However, naturally acquired autobiographical memories differ from memories of standardized stimuli in important ways. Neuroimaging studies of natural memories may reveal distinctive patterns of brain activation and may have particular value in assessing clinical disorders of Memory. This study used functional magnetic resonance imaging to investigate brain activation during successful Retrieval of autobiographical memories elicited by name-cued recall of family members and friends. The caudal part of the left posterior cingulate cortex was the most strongly activated region and was significantly activated in all eight subjects studied. Most subjects also showed significant activation of the left anterior orbitomedial, anterior middle frontal, precuneus, cuneus, and posterior inferior parietal cortices, and the right posterior cingulate and motor cortices.Our findings are consistent with prior studies showing posterior cingulate cortex activation during autobiographical Memory Retrieval. This region is also consistently activated during Retrieval of standardized Memory stimuli when experimental designs emphasizing successful Retrieval are employed. Our results support the hypothesis that the posterior cingulate cortex plays an important role in successful Memory Retrieval. The posterior cingulate cortex has strong reciprocal connections with entorhinal and parahippocampal cortices. Studies of early Alzheimer's disease, temporal lobectomy, and hypoxic amnesia show that hypometabolism of the posterior cingulate cortex is an early and prominent indicator of pathology in these patients. Our findings suggest that autobiographical Memory Retrieval tasks could be used to probe the functional status of the posterior cingulate cortex in patients with early Alzheimer's disease or at risk for that condition.
Christian Otte - One of the best experts on this subject based on the ideXlab platform.
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Sex effects on spatial learning but not on spatial Memory Retrieval in healthy young adults
Behavioural brain research, 2017Co-Authors: Dominique Piber, Katja Wingenfeld, Jan Nowacki, Sven C. Mueller, Christian OtteAbstract:Abstract Objectives Sex differences have been found in spatial learning and spatial Memory, with several studies indicating that males outperform females. We tested in the virtual Morris Water Maze (vMWM) task, whether sex differences in spatial cognitive processes are attributable to differences in spatial learning or spatial Memory Retrieval in a large student sample. Methods We tested 90 healthy students (45 women and 45 men) with a mean age of 23.5 years ( SD = 3.5). Spatial learning and spatial Memory Retrieval were measured by using the vMWM task, during which participants had to search a virtual pool for a hidden platform, facilitated by visual cues surrounding the pool. Several learning trials assessed spatial learning, while a separate probe trial assessed spatial Memory Retrieval. Results We found a significant sex effect during spatial learning, with males showing shorter latency and shorter path length, as compared to females (all p 0.001). Yet, there was no significant sex effect in spatial Memory Retrieval ( p = 0.615). Furthermore, post-hoc analyses revealed significant sex differences in spatial search strategies ( p p = 0.375). Conclusion Our results indicate that in healthy young adults, males show faster spatial learning in a virtual environment, as compared to females. Interestingly, we found no significant sex differences during spatial Memory Retrieval. Our study raises the question, whether men and women use different learning strategies, which nevertheless result in equal performances of spatial Memory Retrieval.
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Cortisol has enhancing, rather than impairing effects on Memory Retrieval in PTSD.
Psychoneuroendocrinology, 2011Co-Authors: Katja Wingenfeld, Martin Driessen, Kirsten Terfehr, Nicole Schlosser, Silvia Carvalho Fernando, Christian Otte, Thomas Beblo, Carsten Spitzer, Bernd Löwe, Oliver T WolfAbstract:Summary Background In the present study, we aimed to compare the effect of exogenous cortisol on Memory Retrieval in posttraumatic stress disorder (PTSD) with the effects in healthy controls. In healthy participants, administration of cortisol impairs declarative Memory Retrieval. Only a few studies have investigated these effects in PTSD yielding mixed results. Methods In a placebo-controlled crossover study, 44 patients with PTSD and 65 healthy controls received either placebo or 10 mg of hydrocortisone orally before Memory testing. In addition to declarative Memory Retrieval (word list learning), we also tested autobiographical Memory Retrieval specificity. Results In both tasks opposing effects of cortisol on Memory were observed when comparing patients with controls. In controls, cortisol had impairing effects on Memory Retrieval, while in PTSD patients cortisol had enhancing effects on Memory Retrieval in both Memory domains. Conclusions The present results suggest beneficial effects of acute cortisol elevations on hippocampal mediated Memory processes in PTSD. Possible neurobiological mechanisms underlying these findings are discussed.
