Lower Episodic Memory Performance Research Articles

Network connectivity underlying episodic memory in children: Application of a pediatric brain tumor survivor injury model.

Episodic memory involves personal experiences paired with their context. The Medial Temporal, Posterior Medial, Anterior Temporal, and Medial Prefrontal networks have been found to support the hippocampus in episodic memory in adults. However, there lacks a model that captures how the structural and functional connections of these networks interact to support episodic memory processing in children. Using diffusion-weighted imaging, magnetoencephalography, and memory tests, we quantified differences in white matter microstructure, neural communication, and episodic memory performance, respectively, of healthy children (n=23) and children with reduced memory performance. Pediatric brain tumor survivors (PBTS; n=24) were used as a model, as they exhibit reduced episodic memory and perturbations in white matter and neural communication. We observed that PBTS, compared to healthy controls, showed significantly (p<0.05) (1) disrupted white matter microstructure between these episodic memory networks through lower fractional anisotropy and higher mean and axial diffusivity, (2) perturbed theta band (4-7Hz) oscillatory synchronization in these same networks through higher weighted phase lag indices (wPLI), and (3) lower episodic memory performance in the Transverse Patterning and Children's Memory Scale (CMS) tasks. Using partial-least squares path modeling, we found that brain tumor treatment predicted network white matter damage, which predicted inter-network theta hypersynchrony and lower verbal learning (directly) and lower verbal recall (indirectly via theta hypersynchrony). Novel to the literature, our findings suggest that white matter modulates episodic memory through effect on oscillatory synchronization within relevant brain networks. RESEARCH HIGHLIGHTS: Investigates the relationship between structural and functional connectivity of episodic memory networks in healthy children and pediatric brain tumor survivors Pediatric brain tumor survivors demonstrate disrupted episodic memory, white matter microstructure and theta oscillatory synchronization compared to healthy children Findings suggest white matter microstructure modulates episodic memory through effects on oscillatory synchronization within relevant episodic memory networks.

Meta-Analysis of Hippocampal Volume and Episodic Memory in Preterm and Term Born Individuals.

Preterm birth (< 37weeks gestation) has been associated with memory deficits, which has prompted investigation of possible alterations in hippocampal volume in this population. However, existing literature reports varying effects of premature birth on hippocampal volume. Specifically, it is unclear whether smaller hippocampal volume in preterm-born individuals is merely reflective of smaller total brain volume. Further, it is not clear if hippocampal volume is associated with episodic memory functioning in preterm-born individuals. Meta-analysis was used to investigate the effects of premature birth on hippocampal volume and episodic memory from early development to young adulthood (birth to 26). PubMed, PsychINFO, and Web of Science were searched for English peer-reviewed articles that included hippocampal volume of preterm and term-born individuals. Thirty articles met the inclusion criteria. Separate meta-analyses were used to evaluate standardized mean differences between preterm and term-born individuals in uncorrected and corrected hippocampal volume, as well as verbal and visual episodic memory. Both uncorrected and corrected hippocampal volume were smaller in preterm-born compared to term-born individuals. Although preterm-born individuals had lower episodic memory performance than term-born individuals, the limited number of studies only permitted a qualitative review of the association between episodic memory performance and hippocampal volume. Tested moderators included mean age, pre/post-surfactant era, birth weight, gestational age, demarcation method, magnet strength, and slice thickness. With this meta-analysis, we provide novel evidence of the effects of premature birth on hippocampal volume.

Plasma amyloid β 42/40 associations on episodic memory: Moderations with depressive symptoms and marital status

AbstractBackgroundPlasma amyloid β (aβ) 42/40 is a non‐invasive and cost‐effective biomarker associated with aβ accumulation and cognitive performance in normal aging and Alzheimer’s disease. Recent studies have linked plasma aβ 42/40 to well established modifiable risk factors for dementia. Specifically, depressive symptoms (DS) and marital status have been associated with steeper cognitive decline and increased dementia onset. We examine whether the association between plasma aβ 42/40 and episodic memory (EM) is moderated by (1) DS, (2) marital status, and (3) additive risk of DS+ marital status.MethodWe used an ethnically and clinically diverse longitudinal cohort of older adults (n=473, mean baseline age=74.81(7.22) years, 60.5% women) from University of California, Davis‐Alzheimer’s Disease Research Center (Table 1). Statistical analyses included latent growth modeling to establish a latent EM growth model, and regression analyses to test independent associations and moderations with DS (measured with Geriatric Depression Scale; low&lt;5/ high≥5), marital status (married/not married), and combined DS+marital status risk (low: low DS+married/intermediate: high DS+married or low DS+not married/high: high DS+not married). Age was centered at 75 years. Sex and education were included as covariates.ResultLower aβ42/40 was associated with lower EM performance and steeper decline (level: β=6.195, SE=3.065, p=0.041, slope: β=0.284, SE=0.134, p=0.034). DS and marital status independently moderated this association. Specifically, lower aβ42/40 was associated with (1) poorer EM performance in the high DS groups (n=80; level: β=8.914, SE=4.353, p=0.014) and (2) poorer EM performance and steeper decline in the married group (n=115; level: β=11.157, SE=4.477, p=0.013, slope: β=0.524, SE=0.219, p=0.017). The effects of these independent associations were magnified with combined DS + marital status. Specifically, lower aβ42/40 was associated with poorer EM performance and steeper decline in the low (n=62; level: β=15.445, SE=5.650, p=0.006, slope: β=0.642, SE=0.305, p=0.035) risk group but this association was absent in the intermediate (n=171) and high (n=56) groups.ConclusionThe impact of amyloidosis, as measured by plasma aβ42/40 on cognition, may be more prominent in married older adults with low DS. Examining multimodal associations of non‐invasive plasma biomarkers with modifiable risk factors may identify older adults with high cognitive decline and dementia risk profiles.

Daytime rest: Association with 24-h rest-activity cycles, circadian timing and cognition in older adults.

Growing epidemiological evidence points towardan association between fragmented 24-h rest-activity cycles and cognition in the aged. Alterations in the circadian timing system might at least partially account for these observations. Here, we tested whether daytime rest (DTR) is associated with changes in concomitant 24-h rest probability profiles, circadian timing and neurobehavioural outcomes in healthy older adults. Sixty-three individuals (59-82 years) underwent field actigraphy monitoring, in-lab dim light melatonin onsetassessment and an extensive cognitive test battery. Actimetry recordings were used to measure DTRfrequency, duration and timing and to extract 24-h rest probability profiles. As expected, increasing DTR frequency was associated not only with higher rest probabilities during the day, but also with lower rest probabilities during the night, suggesting more fragmented night-time rest. Higher DTR frequency was also associated with lower episodic memory performance. Moreover, later DTR timing went along with an advanced circadian phase as well as with an altered phase angle of entrainment between the rest-activity cycle and circadian phase. Our results suggest that different DTR characteristics, as reflective indices of wake fragmentation, are not only underlined by functional consequences on cognition, but also by circadian alteration in the aged.

Episodic Memory Impairment Mediates the Loss of Awareness in Mild Cognitive Impairment.

IntroductionLoss of awareness is a common symptom in Alzheimer's Disease (AD) and responsible for a significant loss of functional abilities. The mechanisms underlying loss of awareness in AD is unknown, although previous findings have implicated dysfunction of primary executive functioning (EF) or episodic memory (EM) to be the cause. Therefore, our main study objective was to explore the involvement of EF and EM dysfunction in amyloid-related loss of awareness across the clinical spectrum of AD.MethodsA total of 895 participants (362 clinically normal [CN], 422 people with mild cognitive impairment [MCI] and 111 with dementia) from the Alzheimer's Disease Neuroimaging Initiative were used for the analyses. A sub-analysis was performed in 202 participants who progressed in their clinical diagnosis from CN to MCI or MCI to dementia as well as dementia patients. Mediation models were used in each clinical group with awareness (assessed with the Everyday Cognitive function questionnaire) as a dependent variable to determine whether EF and/or EM would mediate the effect of amyloid on awareness. We also ran these analyses with subjective and informant complaints as dependent variables. Direct correlations between all variables were also performed.ResultsWe found evidence for a decline in awareness across the groups, with increased awareness observed in the CN group and decreased awareness observed in the MCI and dementia groups. Our results showed that EM, and not EF, partially mediated the relationship between amyloid and awareness such that greater amyloid and lower EM performance was associated with lower awareness. When analyzing each group separately, this finding was only observed in the MCI group and in the group containing progressors and dementia patients. When repeating the analyses for subjective and informant complaints separately, the results were replicated only for the informant's complaints.DiscussionOur results demonstrate that decline in EM and, to a lesser degree, EF, mediate the effect of amyloid on awareness. In line with previous studies demonstrating the development of anosognosia in the prodromal stage, our findings suggest that decreased awareness is the result of an inability for the participant to update his/her insight into his/her cognitive performance (i.e., demonstrating a petrified self).

Associations Between Cognitive Complaints, Memory Performance, Mood, and Amyloid-β Accumulation in Healthy Amyloid Negative Late-Midlife Individuals

Background: Cognitive complaints are gaining more attention as they may represent an early marker of increased risk for AD in individuals without objective decline at standard neuropsychological examination. Objective: Our aim was to assess whether cognitive complaints in late middle-aged individuals not seeking medical help are related to objective cognitive outcomes known as early markers for AD risk, concomitant affective state, and amyloid-β (Aβ) burden. Methods: Eighty-seven community-based cognitively normal individuals aged 50–69 years underwent neuropsychological assessment for global cognition, using Preclinical Alzheimer’s Cognitive Composite 5 (PACC5) score, and a more specific episodic memory measure. Affective state was based on self-assessment questionnaires for depression and anxiety. Aβ PET burden was assessed via [18F]Flutemetamol (N = 84) and [18F]Florbetapir (N = 3) uptake. Cognitive complaints were evaluated using Cognitive Difficulties Scale. Results: Higher cognitive complaints were significantly associated with lower episodic memory performance and worse affective state. Moreover, higher level of cognitive complaints was related to higher (but still sub-clinical) global Aβ accumulation (at uncorrected significance level). Importantly, all three aspects remained significant when taken together in the same statistical model, indicating that they explained distinct parts of variance. Conclusion: In healthy Aβ negative late middle-aged individuals, a higher degree of cognitive complaints is associated with lower episodic memory efficiency, more anxiety and depression, as well as, potentially, with higher Aβ burden, suggesting that complaints might signal subtle decline. Future studies should untangle how cognitive complaints in healthy aging populations are related to longitudinal changes in objective cognition and AD biomarker correlates.

In vivo amyloid progression in healthy middle‐aged to older people at risk of Alzheimer’s disease

AbstractBackgroundPrevious studies applied in‐vivo amyloid staging to amyloid‐sensitive PET scans of healthy older people as well as patients with Alzheimer’s disease (AD) dementia or mild cognitive impairment to characterize stages of amyloid deposition. We adapted this approach to a sample of healthy middle‐aged to older participants at elevated risk for AD due to parental history of AD dementia.MethodWe analyzed 11C‐PiB‐PET scans of 220 participants enrolled in the Wisconsin Registry for Alzheimer’s Prevention (WRAP) (mean age = 61.4y, range: 46‐76y). Distribution volume ratio (DVR) maps were calculated from the dynamic PIB‐PET acquisitions and corrected for partial volume effects. DVR values were extracted from 52 cortical and subcortical regions defined in the Harvard‐Oxford atlas and were used together with global mean DVR values in two‐dimensional Gaussian Mixture Modeling to establish regional thresholds for amyloid‐positivity. Resampled regional frequencies of amyloid‐positivity across participants were used to estimate a four‐stage model of regional amyloid accumulation. We staged individual DVR maps, and assessed the associations between amyloid stage and episodic memory (delayed wordlist recall) and executive function performance (TMT‐B) with Spearman correlation.ResultAccording to the amyloid progression model, stage I involved the anterior and posterior cingulate as well as lateral temporal cortex; stage II had more extensive frontal and temporo‐parietal involvement; stage III proceeded into occipito‐parietal cortical regions and the hippocampus; stage IV extended to the occipital pole, pre‐ and postcentral gyri, and subcortical structures (Figure 1). Out of 220 participants, 36 (16%) were assigned to one of the four amyloid stages, and two cases (1%) deviated from the hierarchical pattern of amyloid accumulation. Higher amyloid stages (I‐IV) correlated with lower executive function (rho = 0.35, p = 0.043), but not with lower episodic memory performance (rho = 0.13, p = 0.48).ConclusionThe estimated 11C‐PiB‐PET‐based amyloid staging model is largely consistent with recently reported amyloid staging models for [F18]‐based amyloid‐PET scans. In this relatively young sample of healthy participants at elevated risk of AD, advanced amyloid stages were rare and not consistently linked to decreased cognitive performance. In future work we will assess whether the derived amyloid stages translate into a stage‐proportional risk of longitudinal cognitive decline in this population.

Suicide Ideation and Neurocognition Among 9- and 10-Year Old Children in the Adolescent Brain Cognitive Development (ABCD) Study

Objective During the past decade, the pediatric suicide rate has nearly tripled. Yet, little is known about suicide behavior (SB) in children. Identification of risk factors associated with SB during childhood may be critical to preventing future attempts. The purpose of this study was to examine the relationship between neurocognitive performance and suicide ideation (SI) in children. Method The present study utilized baseline data from 11,875 participants in the Adolescent Brain Cognitive Development (ABCD) study, a longitudinal study that follows 9- and 10-year-old children through late adolescence to examine factors that influence developmental trajectories. Suicidality was assessed by the Kiddie Schedule for Affective Disorder and Schizophrenia (KSADS) suicide module completed by the parent. Neurocognitive ability was assessed using the NIH Toolbox Cognition measures administered to the youth. Results Children with a history of SI reported by their parent or concordant parent and youth report of SI demonstrated lower performance on the NIH Toolbox Picture Sequence Memory Test compared to children without SI. The difference in performance on the memory task remained significant when including demographic characteristics, family history of suicide, and internalizing symptoms in the model as covariates. Conclusions To our knowledge, this is the first study to identify decreased episodic memory in children with SI. These findings are similar to results from adult and adolescent studies which have reported decreased memory performance among suicide attempters. Deficits in episodic memory may impact a child’s ability to problem-solve and generate potential future outcomes, which may increase the risk for SB. Early identification of memory deficits in children may inform suicide prevention and intervention efforts. Highlights 6% of parents and children reported a history of active suicide ideation in children. Children with a history of suicide ideation had lower episodic memory performance. Early identification of memory deficits may inform suicide intervention efforts.

Patterns of white matter hyperintensities associated with cognition in middle-aged cognitively healthy individuals

White matter hyperintensities (WMH) are commonly detected in the brain of elderly individuals and have been associated with a negative impact on multiple cognitive domains. We aim to investigate the impact of global and regional distribution of WMH on episodic memory and executive function in middle-aged cognitively unimpaired participants [N = 561 (45–75 years)] enriched for Alzheimer’s disease risk factors. WMH were automatically segmented from FLAIR, T1 and FSE MR images. WMH load was calculated both globally and regionally. At each cerebral lobe, regional WMH load was measured at four equidistant layers extending from the lateral ventricles to juxtacortical areas. Cognition was measured by The Memory Binding Test (MBT) and WAIS-IV subtests. Global composite z-scores were calculated for the two cognitive domains. Association between global and regional WMH measurements were sought against cognitive measures, both in global composite scores and in individual subtests. We adjusted cognition and WMH burden for the main sociodemographic (age, sex and education) and genetic factors (APOE-ε4). Memory and executive function were significantly associated with global WMH load. Regionally, lower executive performance was mainly associated with higher deep WMH load in frontal areas and, to a lower degree, in occipital, parietal and temporal regions. Lower episodic memory performance was correlated with higher WMH burden in deep frontal and occipital areas. Our novel methodological approach of regional analysis allowed us to reveal the association between cognition and WMH in strategic brain locations. Our results suggest that, even a small WMH load can impact cognition in cognitively unimpaired middle-aged subjects.

Phosphodiesterase 10A levels are related to striatal function in schizophrenia: a combined positron emission tomography and functional magnetic resonance imaging study

Pharmacological inhibition of phosphodiesterase 10A (PDE10A) is being investigated as a treatment option in schizophrenia. PDE10A acts postsynaptically on striatal dopamine signaling by regulating neuronal excitability through its inhibition of cyclic adenosine monophosphate (cAMP), and we recently found it to be reduced in schizophrenia compared to controls. Here, this finding of reduced PDE10A in schizophrenia was followed up in the same sample to investigate the effect of reduced striatal PDE10A on the neural and behavioral function of striatal and downstream basal ganglia regions. A positron emission tomography (PET) scan with the PDE10A ligand [11C]Lu AE92686 was performed, followed by a 6 min resting-state magnetic resonance imaging (MRI) scan in ten patients with schizophrenia. To assess the relationship between striatal function and neurophysiological and behavioral functioning, salience processing was assessed using a mismatch negativity paradigm, an auditory event-related electroencephalographic measure, episodic memory was assessed using the Rey auditory verbal learning test (RAVLT) and executive functioning using trail-making test B. Reduced striatal PDE10A was associated with increased amplitude of low-frequency fluctuations (ALFF) within the putamen and substantia nigra, respectively. Higher ALFF in the substantia nigra, in turn, was associated with lower episodic memory performance. The findings are in line with a role for PDE10A in striatal functioning, and suggest that reduced striatal PDE10A may contribute to cognitive symptoms in schizophrenia.

Memory performance, oral comprehension and learning process between children with attention deficit hyperactivity disorder and children with anxiety disorder

ABSTRACT Purpose: to compare aspects of memory, learning and oral comprehension between children with Attention Deficit Hyperactivity Disorder (ADHD) and children with Anxiety Disorder (AD). Methods: thirty-two children (7-10 years) were divided into: G1 - children diagnosed with ADHD, and G2 - children diagnosed with AD. The children were not under drug treatment. The tests applied assessed working memory (phonological loop and visuospatial sketch), learning, episodic memory and oral comprehension. Results: both groups showed changes in working memory for visuospatial sketch and phonological loop (worse performance in pseudowords in the ADHD group and digit-reversed order for children with AD), and in oral comprehension. Group comparison showed a statistically significant difference regarding the most complex level of the oral comprehension test and the repetition of nonwords with three syllables. Both groups showed a suitable performance in learning ability, however, the group of children with ADHD suffered from backward interference, with no memory consolidation, showing low episodic memory performance. Conclusion: children with ADHD and anxiety disorder showed various altered cognitive skills, although group comparison revealed that children with ADHD exhibited worse cognitive performance.

Low episodic memory performance in cognitively normal elderly subjects is associated with increased posterior cingulate gray matter N-acetylaspartate: a 1H MRSI study at 7 Tesla

Low episodic memory performance characterizes elderly subjects at increased risk for Alzheimer's disease (AD) and may reflect neuronal dysfunction within the posterior cingulate cortex and precuneus (PCP) region. To investigate a potential association between cerebral neurometabolism and low episodic memory in the absence of cognitive impairment, tissue-specific magnetic resonance spectroscopic imaging at ultrahigh field strength of 7 Tesla was used to investigate the PCP region in a healthy elderly study population (n = 30, age 70 ± 5.7 years, Mini–Mental State Examination 29.4 ± 4.1). The Verbal Learning and Memory Test (VLMT) was administered as part of a neuropsychological battery for assessment of episodic memory performance. Significant differences between PCP gray and white matter could be observed for glutamate-glutamine (p = 0.001), choline (p = 0.01), and myo-inositol (p = 0.02). Low Verbal Learning and Memory Test performance was associated with high N-acetylaspartate in PCP gray matter (p = 0.01) but not in PCP white matter. Our data suggest that subtle decreases in episodic memory performance in the elderly may be associated with increased levels of N-acetylaspartate as a reflection of increased mitochondrial energy capacity in PCP gray matter.

Motor phenotype of decline in cognitive performance among community-dwellers without dementia: population-based study and meta-analysis.

BackgroundDecline in cognitive performance is associated with gait deterioration. Our objectives were: 1) to determine, from an original study in older community-dwellers without diagnosis of dementia, which gait parameters, among slower gait speed, higher stride time variability (STV) and Timed Up & Go test (TUG) delta time, were most strongly associated with lower performance in two cognitive domains (i.e., episodic memory and executive function); and 2) to quantitatively synthesize, with a systematic review and meta-analysis, the association between gait performance and cognitive decline (i.e., mild cognitive impairment (MCI) and dementia).MethodsBased on a cross-sectional design, 934 older community-dwellers without dementia (mean±standard deviation, 70.3±4.9years; 52.1% female) were recruited. A score at 5 on the Short Mini-Mental State Examination defined low episodic memory performance. Low executive performance was defined by clock-drawing test errors. STV and gait speed were measured using GAITRite system. TUG delta time was calculated as the difference between the times needed to perform and to imagine the TUG. Then, a systematic Medline search was conducted in November 2013 using the Medical Subject Heading terms “Delirium,” “Dementia,” “Amnestic,” “Cognitive disorders” combined with “Gait” OR “Gait disorders, Neurologic” and “Variability.”FindingsA total of 294 (31.5%) participants presented decline in cognitive performance. Higher STV, higher TUG delta time, and slower gait speed were associated with decline in episodic memory and executive performances (all P-values <0.001). The highest magnitude of association was found for higher STV (effect size = −0.74 [95% Confidence Interval (CI): −1.05;−0.43], among participants combining of decline in episodic memory and in executive performances). Meta-analysis underscored that higher STV represented a gait biomarker in patients with MCI (effect size = 0.48 [95% CI: 0.30;0.65]) and dementia (effect size = 1.06 [95% CI: 0.40;1.72]).ConclusionHigher STV appears to be a motor phenotype of cognitive decline.

Cortical thickness mediates the effect of β-amyloid on episodic memory

To investigate the associations among β-amyloid (Aβ), cortical thickness, and episodic memory in a cohort of cognitively normal to mildly impaired individuals at increased risk of vascular disease. In 67 subjects specifically recruited to span a continuum of cognitive function and vascular risk, we measured brain Aβ deposition using [(11)C] Pittsburgh compound B-PET imaging and cortical thickness using MRI. Episodic memory was tested using a standardized composite score of verbal memory, and vascular risk was quantified using the Framingham Coronary Risk Profile index. Increased Aβ was associated with cortical thinning, notably in frontoparietal regions. This relationship was strongest in persons with high Aβ deposition. Increased Aβ was also associated with lower episodic memory performance. Cortical thickness was found to mediate the relationship between Aβ and memory performance. While age had a marginal effect on these associations, the relationship between Aβ and cortical thickness was eliminated after controlling for vascular risk except when examined in only Pittsburgh compound B-positive subjects, in whom Aβ remained associated with thinner cortex in precuneus and occipital lobe. In addition, only the precuneus was found to mediate the relationship between Aβ and memory after controlling for vascular risk. These results suggest strong links among Aβ, cortical thickness, and memory. They highlight that, in individuals without dementia, vascular risk also contributes to cortical thickness and influences the relationships among Aβ, cortical thickness, and memory.

Episodic Memory in Detoxified Alcoholics: Contribution of Grey Matter Microstructure Alteration

Even though uncomplicated alcoholics may likely have episodic memory deficits, discrepancies exist regarding to the integrity of brain regions that underlie this function in healthy subjects. Possible relationships between episodic memory and 1) brain microstructure assessed by magnetic resonance diffusion tensor imaging (DTI), 2) brain volumes assessed by voxel-based morphometry (VBM) were investigated in uncomplicated, detoxified alcoholics.Diffusion and morphometric analyses were performed in 24 alcohol dependent men without neurological or somatic complications and in 24 healthy men. The mean apparent coefficient of diffusion (ADC) and grey matter volumes were measured in the whole brain. Episodic memory performance was assessed using a French version of the Free and Cued Selective Reminding Test (FCSRT). Correlation analyses between verbal episodic memory, brain microstructure, and brain volumes were carried out using SPM2 software.In those with alcohol dependence, higher ADC was detected mainly in frontal, temporal and parahippocampal regions, and in the cerebellum. In alcoholics, regions with higher ADC typically also had lower grey matter volume. Low verbal episodic memory performance in alcoholism was associated with higher mean ADC in parahippocampal areas, in frontal cortex and in the left temporal cortex; no correlation was found between regional volumes and episodic memory scores. Regression analyses for the control group were not significant.These findings support the hypothesis that regional microstructural but no macrostructural alteration of the brain might be responsible, at least in part, for episodic memory deficits in alcohol dependence.

P3-105: Low episodic memory performance is related to high PET PIB levels in asymptomatic control subjects

P3-105: Low episodic memory performance is related to high PET PIB levels in asymptomatic control subjects

Low episodic memory performance as a premorbid marker of depression: evidence from a 3‐year follow‐up

To examine low episodic memory scores as a potential risk factor for depression. A population-based sample of non-depressed individuals (20-64 years) were re-examined 3 years after an initial screening (n = 708). At baseline, information on episodic memory scores, demographic and socioeconomic factors, alcohol use and anxiety diagnoses was collected. The data for depression diagnoses were collected at both baseline and follow-up. Logistic regressions, conducted on three separate study groups that were defined according to three assessments of episodic memory (i.e. free + cued recall, free recall, cued recall) among individuals who scored in the 25 lowest or highest percentiles in the memory tests, revealed that low episodic memory performance defined as the sum of free and cued recalls of organizable words constitutes a risk of depression diagnosis 3 years later. Low episodic memory performance predated depressive diagnosis and might be considered as a premorbid marker of depression.

Low episodic memory performance as a premorbid marker of depression: Evidence from a 3-year follow-up

Objective: To examine low episodic memory scores as a potential risk factor for depression.Method: A population-based sample of non-depressed individuals (20–64 years) were re-examined 3 years afte ...

Mild cognitive impairment in different functional domains and incident Alzheimer’s disease

Background: Little is known about factors that predict transition from mild cognitive impairment to Alzheimer’s disease (AD). Objective: To examine the relation of impairment in different cognitive systems to risk...