Correlates Of Autobiographical Memory Research Articles

Cerebral correlates of autobiographical memory in MCI and AD: Evidence from a positron‐emission tomography study

AbstractBackgroundAutobiographical memory (AM) changes are the hallmark of Alzheimer’s disease (AD) and Mild Cognitive Impairment (MCI). In recent neuroimaging studies, AM changes were associated with numerous cerebral sites, such as the frontal cortices, the mesial temporal lobe, or the cingulum. Factor analysis provides statistical methods for evaluating patterns of cerebral changes in regional glucose uptake.MethodIn 109 patients with MCI or mild AD cerebral metabolic rates were determined using positron‐emission tomography with [18F] deoxyglucose. According to the analyses of the scree plot factor analysis with VARIMAX rotation was used to identify underlying dimensions in 34 cerebral sites involved in AM deterioration. Subsequently, the respective factor scores were correlated with AM performance of 22 patients, which was measured with a structured inventory assessing memories from primary school, early adulthood, and recent years.ResultFactor analysis identified seven factors explaining 69 % of the variance (“frontal cortex,” “mesial temporal substructures”, “cingulum”, “occipital cortex”, “left temporo‐prefrontal areas”, “anterior cingulum”, “right temporal cortex”). Relative to controls, AD patients showed significantly lower values on the factors “frontal cortex” and “mesial temporal substructures”. The factor “mesial temporal substructures” was significantly correlated with both, episodic memories and personal semantic knowledge.ConclusionInterestingly, changes of the mesial temporal substructures were correlated with both semantic and episodic AM. These findings don’t necessarily contradict the multiple trace hypothesis as our sample only comprised patients with MCI or very mild AD for whom the relative preservation of semantic relative to episodic AM may not apply. In conclusion, our findings underline the importance of functional mesial temporal lobe changes in AD associated AM deficits.

Neural correlates of retrieval-based enhancement of autobiographical memory in older adults

Lifelog photo review is considered to enhance the recall of personal events. While a sizable body of research has explored the neural basis of autobiographical memory (AM), there is limited neural evidence on the retrieval-based enhancement effect on event memory among older adults in the real-world environment. This study examined the neural processes of AM as was modulated by retrieval practice through lifelog photo review in older adults. In the experiment, blood-oxygen-level dependent response during subjects’ recall of recent events was recorded, where events were cued by photos that may or may not have been exposed to a priori retrieval practice (training). Subjects remembered more episodic details under the trained relative to non-trained condition. Importantly, the neural correlates of AM was exhibited by (1) dissociable cortical areas related to recollection and familiarity, and (2) a positive correlation between the amount of recollected episodic details and cortical activation within several lateral temporal and parietal regions. Further analysis of the brain activation pattern at a few regions of interest within the core remember network showed a training_condition × event_detail interaction effect, suggesting that the boosting effect of retrieval practice depended on the level of recollected event details.

Behavioural and neural correlates of autobiographical memory and future thinking in depression

Event Abstract Back to Event Behavioural and neural correlates of autobiographical memory and future thinking in depression Donna Rose Addis1*, Sylvia Hach1 and Lynette J. Tippett1 1 The University of Auckland, School of Psychology, New Zealand Background: Major depressive disorder (MDD) is associated with a decrease in the specificity of past and future events: When engaged in autobiographical memory (AM) or future thinking (FT) tasks, patients with a history of MDD generate more generic events compared to non-depressed individuals. The CaRFAX model proposes that reduced event specificity results from a combination of rumination, functional avoidance as well as executive dysfunction. In this study, we tested the contribution of CaRFAX model components to the specificity of past and future events in MDD. Moreover, we explored whether there are differences in the neural correlates of AM and FT during the generation of specific events from the past and future. Methods: In Session 1, participants (17 MDD, 16 controls) completed measures of rumination, avoidance and executive function (working memory, inhibition, set-shifting and strategy use). In Session 2 (fMRI), participants generated past and future events in response to cues (e.g., getting/losing a pet). Events were scored for specificity during a post-scan interview. For the fMRI analysis (using spatiotemporal task Partial Least Squares), behaviour was matched across groups by only analysing trials on which specific events were generated. Results: The MDD group were more ruminative and avoidant than controls, and generated fewer specific events during the AM and FT task. However, there were no group differences in executive function. Regressions revealed that strategy use (as indexed by CVLT semantic clustering) was associated with specificity over and above depression severity, rumination and avoidance. fMRI analyses showed that both groups engaged regions typically associated with AM and FT. However, the MDD group showed reduced activity in temporal regions (hippocampus, temporal pole) and increased recruitment of frontal regions (e.g., inferior frontal gyrus). Discussion: Our results suggest that strategic abilities and neural changes both play an important role in the generation of specific past and future events in MDD. Strategic ability predicts event specificity over and above measures of rumination and avoidance. Although the MDD group was able to engage the same network as controls, they did exhibit reductions in key regions, such as the hippocampus, consistent with reports of hippocampal atrophy in MDD. However, prefrontal regions were over-activated in MDD, which may reflect greater executive demands and/or compensatory activation. Acknowledgements This work was funded by a Rutherford Discovery Fellowship (DRA). Keywords: Depression, autobiographical memory, Future thinking, fMRI, Executive Function Conference: ACNS-2013 Australasian Cognitive Neuroscience Society Conference, Clayton, Melbourne, Australia, 28 Nov - 1 Dec, 2013. Presentation Type: Oral Topic: Memory Citation: Addis D, Hach S and Tippett LJ (2013). Behavioural and neural correlates of autobiographical memory and future thinking in depression. Conference Abstract: ACNS-2013 Australasian Cognitive Neuroscience Society Conference. doi: 10.3389/conf.fnhum.2013.212.00191 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 15 Oct 2013; Published Online: 25 Nov 2013. * Correspondence: Dr. Donna Rose Addis, The University of Auckland, School of Psychology, Auckland, New Zealand, d.addis@auckland.ac.nz Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Donna Rose Addis Sylvia Hach Lynette J Tippett Google Donna Rose Addis Sylvia Hach Lynette J Tippett Google Scholar Donna Rose Addis Sylvia Hach Lynette J Tippett PubMed Donna Rose Addis Sylvia Hach Lynette J Tippett Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

The functional neuroanatomy of odor evoked autobiographical memories cued by odors and words

Behavioral evidence indicates that odor evoked autobiographical memories (OEAMs) are older, more emotional, less thought of and induce stronger time traveling characteristics than autobiographical memories (AMs) evoked by other modalities. The main aim of this study was to explore the neural correlates of AMs evoked by odors as a function of retrieval cue. Participants were screened for specific OEAMs and later presented with the odor cue and its verbal referent in an fMRI paradigm. Because the same OEAM was retrieved across both cue formats (odor and word), potential cue dependent brain activations were investigated. The overall results showed that odor and word cued OEAMs activated regions typically associated with recollection of autobiographical information. Although no odors were presented, a verbal cuing of the OEAMs activated areas associated with olfactory perception (e.g., piriform cortex). However, relative to word cuing, an odor cuing of OEAMs resulted in more activity in MTL regions such as the parahippocampus, and areas involved in visual vividness (e.g., occipital gyrus and precuneus). Furthermore, odor cues activated areas related to emotional processing, such as limbic and tempopolar regions significantly more. In contrast, word cues relative to odor cues recruited a more widespread and bilateral prefrontal activity. Hippocampus activity did not vary as function of the remoteness of the memory, but recollection of OEAMs from the 1st vs the 2nd decade of life showed specific activation in the right OFC, whereas the 2nd reflected a higher activation in the left inferior frontal gyrus.

Functional anatomy of autobiographical memory recall deficits in depression

BackgroundMajor depressive disorder (MDD) is associated with deficits in recalling specific autobiographical memories (AMs). Extensive research has examined the functional anatomical correlates of AM in healthy humans, but no studies have examined the neurophysiological underpinnings of AM deficits in MDD. The goal of the present study was to examine the differences in the hemodynamic response between patients with MDD and controls while they engage in AM recall.MethodParticipants (12 unmedicated MDD patients; 14 controls) underwent functional magnetic resonance imaging (fMRI) scanning while recalling AMs in response to positive, negative and neutral cue words. The hemodynamic response during memory recall versus performing subtraction problems was compared between MDD patients and controls. Additionally, a parametric linear analysis examined which regions correlated with increasing arousal ratings.ResultsBehavioral results showed that relative to controls, the patients with MDD had fewer specific (p=0.013), positive (p=0.030), highly arousing (p=0.036) and recent (p=0.020) AMs, and more categorical (p<0.001) AMs. The blood oxygen level-dependent (BOLD) response in the parahippocampus and hippocampus was higher for memory recall versus subtraction in controls and lower in those with MDD. Activity in the anterior insula was lower for specific AM recall versus subtraction, with the magnitude of the decrement greater in MDD patients. Activity in the anterior cingulate cortex was positively correlated with arousal ratings in controls but not in patients with MDD.ConclusionsWe replicated previous findings of fewer specific and more categorical AMs in patients with MDD versus controls. We found differential activity in medial temporal and prefrontal lobe structures involved in AM retrieval between MDD patients and controls as they engaged in AM recall. These neurophysiological deficits may underlie AM recall impairments seen in MDD.