Browsing by Subject "Episodic memory"

Now showing 1 - 6 of 6
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    Autobiographical memory in schizophrenia: The role of metacognition
    (Elsevier, 2021) Mediavilla, Roberto; López-Arroyo, Manuel; Gómez-Arnau, Jorge; Wiesepape, Courtney; Lysaker, Paul H.; Lahera, Guillermo; Psychiatry, School of Medicine
    Background: Autobiographical memory is an important component of declarative memory, which refers to the ability to recall personal events that happened in the past. This requires that the person senses or experiences himself/herself in the past (i.e., conscious recollection). For people with schizophrenia, conscious recollection can be particularly difficult, resulting in difficulty accessing detailed, specific autobiographical information. Our hypothesis is that the ability to monitor and think about one's cognitive processes (metacognition) is a requisite for conscious recollection, and that it mediates the association between having schizophrenia and recalling fewer specific, personal memories. Methods: Participants were 30 adults with schizophrenia and 30 matched healthy controls. The main assessment instruments were the Metacognition Assessment Scale-Abbreviated (MAS-A) and the Autobiographical Memory Test (AMT). Severity of symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS) for schizophrenia. Cognitive performance was measured with the Screen for Cognitive Impairment in Psychiatry (SCIP). Mediation analysis was conducted following Baron and Kenny's procedure. Results: People with schizophrenia had more semantic associations and fewer specific memories than controls in the AMT. Metacognition (MAS-A total score) partially mediated the association between having schizophrenia and recalling fewer specific past events, even after controlling for cognitive impairment as a potential confounding source. Conclusions: Metacognitive ability, which can be improved with available programs, intervenes in the process of accessing autobiographical memories in people with schizophrenia. Practical implications of this finding are discussed.
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    Decreased body mass index in the preclinical stage of autosomal dominant Alzheimer's disease
    (SpringerNature, 2017-04-27) Müller, Stephan; Preische, Oliver; Sohrabi, Hamid R.; Gräber, Susanne; Jucker, Mathias; Dietzsch, Janko; Ringman, Ralph N.; Martins, Ralph N.; McDade, Eric; Schofield, Peter R.; Ghetti, Bernardino; Rossor, Martin; Graff-Radford, Neill R.; Levin, Johannes; Galasko, Douglas; Quaid, Kimberly A.; Salloway, Stephen; Xiong, Chengjie; Benzinger, Tammie; Buckles, Virginia; Masters, Colin L.; Sperling, Reisa; Bateman, Randall J.; Morris, John C.; Laske, Christoph; Department of Pathology and Laboratory Medicine, School of Medicine
    The relationship between body-mass index (BMI) and Alzheimer´s disease (AD) has been extensively investigated. However, BMI alterations in preclinical individuals with autosomal dominant AD (ADAD) have not yet been investigated. We analyzed cross-sectional data from 230 asymptomatic members of families with ADAD participating in the Dominantly Inherited Alzheimer Network (DIAN) study including 120 preclinical mutation carriers (MCs) and 110 asymptomatic non-carriers (NCs). Differences in BMI and their relation with cerebral amyloid load and episodic memory as a function of estimated years to symptom onset (EYO) were analyzed. Preclinical MCs showed significantly lower BMIs compared to NCs, starting 11.2 years before expected symptom onset. However, the BMI curves begun to diverge already at 17.8 years before expected symptom onset. Lower BMI in preclinical MCs was significantly associated with less years before estimated symptom onset, higher global Aβ brain burden, and with lower delayed total recall scores in the logical memory test. The study provides cross-sectional evidence that weight loss starts one to two decades before expected symptom onset of ADAD. Our findings point toward a link between the pathophysiology of ADAD and disturbance of weight control mechanisms. Longitudinal follow-up studies are warranted to investigate BMI changes over time.
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    Effect of chemotherapy on default mode network connectivity in older women with breast cancer
    (Springer, 2022) Chen, Bihong T.; Chen, Zikuan; Patel, Sunita K.; Rockne, Russell C.; Wong, Chi Wah; Root, James C.; Saykin, Andrew J.; Ahles, Tim A.; Holodny, Andrei I.; Sun, Can-Lan; Sedrak, Mina S.; Kim, Heeyoung; Celis, Ashley; Katheria, Vani; Dale, William; Radiology and Imaging Sciences, School of Medicine
    Chemotherapy may impair cognition and contribute to accelerated aging. The purpose of this study was to assess the effects of chemotherapy on the connectivity of the default mode network (DMN) in older women with breast cancer. This prospective longitudinal study enrolled women aged ≥60 years with stage I–III breast cancer (CTx group) and matched healthy controls (HC group). Study assessments, consisting of resting-state functional MRI (rs-fMRI) and the Picture Sequence Memory (psm) test for episodic memory from the NIH Toolbox for Cognition, were obtained at baseline and within one month after the completion of chemotherapy for the CTx group and at matched intervals for the HC group. Two-sample t-test and FDR multiple comparison were used for statistical inference. Our analysis of the CTx group (N=19; 60–82 years of age, mean=66.6, SD=5.24) compared to the HC group (N=14; 60–78 years of age, mean=68.1, SD=5.69) revealed weaker DMN subnetwork connectivity in the anterior brain but stronger connectivity in the posterior brain at baseline. After chemotherapy, this pattern was reversed, with stronger anterior connectivity and weaker posterior connectivity. In addition, the meta-level functional network connectivity (FNC) among DMN subnetworks after chemotherapy was consistently weaker than the baseline FNC as seen in the couplings between anterior cingulate cortex (ACC) and retrosplenial (rSplenia) region, with ΔFNC(‘ACC’,’rSplenia’)=−0.14, t value=−2.44, 95%CI=[−0.27, −0.10], pFDR<0.05). The baseline FNC matrices of DMN subnetworks were correlated with psm scores (corr=0.58, p<0.05). Our results support DMN alterations as a potential neuroimaging biomarker for cancer-related cognitive impairment and accelerated aging.
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    Functional neuroanatomical correlates of episodic memory impairment in early phase psychosis
    (SpringerNature, 2016-03) Francis, Michael Matthew; Hummer, Tom A.; Vohs, Jenifer L.; Yung, Matthew G.; Liffick, Emily; Mehdiyoun, Nicole F.; Radnovich, Alexander J.; McDonald, Brenna C.; Saykin, Andrew J.; Breier, Alan; Department of Psychiatry, IU School of Medicine
    Studies have demonstrated that episodic memory (EM) is often preferentially disrupted in schizophrenia. The neural substrates that mediate EM impairment in this illness are not fully understood. Several functional magnetic resonance imaging (fMRI) studies have employed EM probe tasks to elucidate the neural underpinnings of impairment, though results have been inconsistent. The majority of EM imaging studies have been conducted in chronic forms of schizophrenia with relatively few studies in early phase patients. Early phase schizophrenia studies are important because they may provide information regarding when EM deficits occur and address potential confounds more frequently observed in chronic populations. In this study, we assessed brain activation during the performance of visual scene encoding and recognition fMRI tasks in patients with earlyphase psychosis (n = 35) and age, sex, and race matched healthy control subjects (n = 20). Patients demonstrated significantly lower activation than controls in the right hippocampus and left fusiform gyrus during scene encoding and lower activation in the posterior cingulate, precuneus, and left middle temporal cortex during recognition of target scenes. Symptom levels were not related to the imaging findings, though better cognitive performance in patients was associated with greater right hippocampal activation during encoding. These results provide evidence of altered function in neuroanatomical circuitry subserving EM early in the course of psychotic illness, which may have implications for pathophysiological models of this illness.
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    Pathways to dementia: genetic predictors of cognitive and brain imaging endophenotypes in Alzheimer's disease
    (2014-01-03) Ramanan, Vijay K; Saykin, Andrew J.; Foroud, Tatiana; Herbert, Brittney-Shea; McDonald, Brenna C.; Shen, Li
    Alzheimer's disease (AD) is a national priority, with nearly six million Americans affected at an annual cost of $200 billion and no available cure. A better understanding of the mechanisms underlying AD is crucial to combat its high and rising incidence and burdens. Most cases of AD are thought to have a complex etiology with numerous genetic and environmental factors influencing susceptibility. Recent genome-wide association studies (GWAS) have confirmed roles for several hypothesized genes and have discovered novel loci associated with disease risk. However, most GWAS-implicated genetic variants have displayed modest individual effects on disease risk and together leave substantial heritability and pathophysiology unexplained. As a result, new paradigms focusing on biological pathways have emerged, drawing on the hypothesis that complex diseases may be influenced by collective effects of multiple variants – of a variety of effect sizes, directions, and frequencies – within key biological pathways. A variety of tools have been developed for pathway-based statistical analysis of GWAS data, but consensus approaches have not been systematically determined. We critically review strategies for genetic pathway analysis, synthesizing extant concepts and methodologies to guide application and future development. We then apply pathway-based approaches to complement GWAS of key AD-related endophenotypes, focusing on two early, hallmark features of disease, episodic memory impairment and brain deposition of amyloid-β. Using GWAS and pathway analysis, we confirmed the association of APOE (apolipoprotein E) and discovered additional genetic modulators of memory functioning and amyloid-β deposition in AD, including pathways related to long-term potentiation, cell adhesion, inflammation, and NOTCH signaling. We also identified genetic associations to amyloid-β deposition that have classically been understood to mediate learning and memory, including the BCHE gene and signaling through the epidermal growth factor receptor. These findings validate the use of pathway analysis in complex diseases and illuminate novel genetic mechanisms of AD, including several pathways at the intersection of disease-related pathology and cognitive decline which represent targets for future studies. The complexity of the AD genetic architecture also suggests that biomarker and treatment strategies may require simultaneous targeting of multiple pathways to effectively combat disease onset and progression.
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    Recognition memory and divergent cognitive profiles in prodromal genetic frontotemporal dementia
    (Elsevier, 2021) Barker, Megan S.; Manoochehri, Masood; Rizer, Sandra J.; Appleby, Brian S.; Brushaber, Danielle; Dev, Sheena I.; Devick, Katrina L.; Dickerson, Bradford C.; Fields, Julie A.; Foroud, Tatiana M.; Forsberg, Leah K.; Galasko, Douglas R.; Ghoshal, Nupur; Graff-Radford, Neill R.; Grossman, Murray; Heuer, Hilary W.; Hsiung, Ging-Yuek; Kornak, John; Litvan, Irene; Mackenzie, Ian R.; Mendez, Mario F.; Pascual, Belen; Rankin, Katherine P.; Rascovsky, Katya; Staffaroni, Adam M.; Tartaglia, Maria Carmela; Weintraub, Sandra; Wong, Bonnie; Boeve, Bradley F.; Boxer, Adam L.; Rosen, Howard J.; Goldman, Jill; Huey, Edward D.; Cosentino, Stephanie; ALLFTD consortium; Medical and Molecular Genetics, School of Medicine
    Although executive dysfunction is the characteristic cognitive marker of behavioral variant frontotemporal dementia (bvFTD), episodic memory deficits are relatively common, and may be present even during the prodromal disease phase. In a cohort of mutation carriers with mild behavioral and/or cognitive symptoms consistent with prodromal bvFTD, we aimed to investigate patterns of performance on an abbreviated list learning task, with a particular focus on recognition memory. We further aimed to characterize the cognitive prodromes associated with the three major genetic causes of frontotemporal dementia, as emerging evidence suggests there may be subtle differences in cognitive profiles among carriers of different genetic mutations. Participants included 57 carriers of a pathogenic mutation in microtubule-associated protein tau (MAPT, N = 23), or progranulin (GRN, N = 15), or a or a hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9orf72, N = 19), with mild cognitive and/or behavioral symptoms consistent with prodromal bvFTD. Familial non-carriers were included as controls (N = 143). All participants completed a comprehensive neuropsychological examination, including an abbreviated list learning test assessing episodic memory recall and recognition. MAPT mutation carriers performed worse than non-carriers in terms of list recall, and had difficulty discriminating targets from distractors on the recognition memory task, primarily due to the endorsement of distractors as targets. MAPT mutation carriers also showed nonverbal episodic memory and semantic memory dysfunction (object naming). GRN mutation carriers were variable in performance and overall the most dysexecutive. Slowed psychomotor speed was evident in C9orf72 repeat expansion carriers. Identifying the earliest cognitive indicators of bvFTD is of critical clinical and research importance. List learning may be a sensitive cognitive marker for incipient dementia in MAPT and potentially a subset of GRN carriers. Our results highlight that distinct cognitive profiles may be evident in carriers of the three disease-causing genes during the prodromal disease stage.