Poor Memory Function Research Articles

Memory function and early exit from paid employment through different pathways among ageing European workers.

Understanding memory function's role in early workforce exit is key in supporting sustainable employment among ageing workers. This study examined the impact of memory function on early exit from paid employment, analyzed changes in memory function before, during and after such transitions, and assessed memory function trajectories in relation to the presence or absence of effort-reward imbalance at work. This study included 16 339 respondents from the Survey of Health, Ageing, and Retirement in Europe (SHARE) between age 50 and the country-specific retirement age. The effects of objective and subjective memory functioning on early exit were assessed using Cox proportional hazards with Fine-Gray sub distribution models. Changes in memory function before and after a transition to non-employment were assessed using generalized linear mixed-effects models. These changes were described and compared based on exposure to job effort-reward imbalance. Workers with poor subjective memory were 2.3 times more likely to exit employment prematurely due to disability ([sub-distribution hazard ratio (SHR) 2.30, 95% confidence interval (CI) 1.77-3.00] and 1.3 times more likely to exit through unemployment (SHR 1.29, 95% CI 1.06-1.55). Workers with low objective memory were 1.6 times more likely to exit through unemployment (SHR 1.56, 95% CI 1.30-1.87). Subjective memory generally declined prior to, and during early exit from paid employment. While subjective memory generally improved post-exit, objective memory function declined after exiting. An accelerated decline in objective memory functioning was noted among early retirees who had been exposed to effort-reward imbalance at work (β -0.45, standard error 0.16). Workers with poor memory function are at higher risk of early involuntary exit from paid employment. Promoting memory function and balancing job efforts and rewards may help mitigate the risk of a premature exit.

Dedifferentiation of caudate functional organization is linked to reduced D1 dopamine receptor availability and poorer memory function in aging

Abstract Age-related alterations in cortico-striatal function have been highlighted as an important determinant of declines in flexible, higher-order, cognition in older age. However, the mechanisms underlying such alterations remain poorly understood. Computational accounts propose age-related dopaminergic decreases to impoverish neural gain control, possibly contributing to reduced specificity of cortico-striatal circuits, that are modulated by dopamine, in older age. Using multi-modal neuroimaging data (fMRI, PET) from a large lifespan cohort (n = 180), we assessed the relationship between dopamine D1-like receptors (D1DRs) and cortico-striatal function during rest and an n-back working memory task. The results revealed gradual age-related decreases in the specificity of functional coupling between the centrolateral caudate and cortical association networks during both rest and working memory, which in turn was associated with poorer short and long-term memory performance with older age. Critically, reduced D1DR availability in the caudate and the prefrontal cortex predicted less differentiated caudate-cortical coupling across the lifespan, in part accounting for the age-related declines observed on this metric. These findings provide novel empirical evidence for a key role of dopamine in maintaining functional specialization of cortico-striatal circuits as individuals age, bridging with computational models of deficient catecholaminergic neuromodulation underpinning age-related dedifferentiation of brain function.

Memory anosognosia in early Alzheimer's disease: A memory clinic study.

Unawareness or anosognosia of memory impairment is a common phenomenon in patients with Alzheimer's disease (AD). Different findings have been reported regarding its presentation, assessment procedure, and cognitive correlates. To assess memory awareness of early AD patients predictively (before memory testing) and online (immediately after performing a memory test). All participants were outpatients of a memory clinic. AD patients were compared with participants having mild cognitive impairment (MCI) and a group with normal cognitive aging (NC). We used a performance-based assessment procedure to measure self-perceived memory abilities. An anosognosia ratio was calculated by matching self-estimates with objective memory scores derived from the Consortium to Establish a Registry for Alzheimer's disease Neuropsychological battery. Memory anosognosia in terms of self-overestimation was found in almost half of the AD sample, only rarely in MCI, and was not present in NC. Most AD patients had both, a low prediction and also a deficient online accuracy of self-estimation. Memory overestimators were older, less educated, and had significantly poorer neuropsychological scores. A stepwise linear regression analysis showed that memory anosognosia was predicted by age, everyday functional abilities and neuropsychological variables, including executive and mnestic abilities. Poor cognitive and memory functions combined with memory anosognosia are a hallmark of early AD. Further, mnemonic anosognosia as assessed by performance based measures separates AD patients already in the early disease stage from subjects with MCI or normal controls. Our findings highlight the importance of assessing memory self-appraisal in subjects attending a memory clinic, in addition to clinical and cognitive variables.

Decoding EEG for optimizing naturalistic memory

Spectral features of human electroencephalographic (EEG) recordings during learning predict subsequent recall variability. Capitalizing on these fluctuating neural features, we develop a non-invasive closed-loop (NICL) system for real-time optimization of human learning. Participants play a virtual navigation-and-memory game; recording multi-session data across days allowed us to build participant-specific classification models of recall success. In subsequent closed-loop sessions, our platform manipulated the timing of memory encoding, selectively presenting items during periods of predicted good or poor memory function based on EEG features decoded in real time. The induced memory effect (the difference between recall rates when presenting items during predicted good vs. poor learning periods) increased with the accuracy of neural decoding. This study demonstrates greater-than-chance memory decoding from EEG recordings in a naturalistic virtual navigation task with greater real-world validity than basic word-list recall paradigms. Here we modulate memory by timing stimulus presentation based on noninvasive scalp EEG recordings, whereas prior closed-loop studies for memory improvement involved intracranial recordings and direct electrical stimulation. Other noninvasive studies have investigated the use of neurofeedback or remedial study for memory improvement. These findings present a proof-of-concept for using non-invasive closed-loop technology to optimize human learning and memory through principled stimulus timing, but only in those participants for whom classifiers reliably predict out-of-sample memory function.

Altered fornix integrity is associated with sleep apnea-related hypoxemia in mild cognitive impairment.

The limbic system is critical for memory function and degenerates early in the Alzheimer's disease continuum. Whether obstructive sleep apnea (OSA) is associated with alterations in the limbic white matter tracts remains understudied. Polysomnography, neurocognitive assessment, and brain magnetic resonance imaging (MRI) were performed in 126 individuals aged 55-86 years, including 70 cognitively unimpaired participants and 56 participants with mild cognitive impairment (MCI). OSA measures of interest were the apnea-hypopnea index and composite variables of sleep fragmentation and hypoxemia. Microstructural properties of the cingulum, fornix, and uncinate fasciculus were estimated using free water-corrected diffusion tensor imaging. Higher levels of OSA-related hypoxemia were associated with higher left fornix diffusivities only in participants with MCI. Microstructure of the other white matter tracts was not associated with OSA measures. Higher left fornix diffusivities correlated with poorer episodic verbal memory. OSA may contribute to fornix damage and memory dysfunction in MCI. Sleep apnea-related hypoxemia was associated with altered fornix integrity in MCI. Altered fornix integrity correlated with poorer memory function. Sleep apnea may contribute to fornix damage and memory dysfunction in MCI.

P-33 A rare form of diabetes: MELAS

Abstract Introduction MELAS (mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes) is a fatal multisystemic condition caused by a mitochondrial DNA mutation, the most prevalent is m.3243AAG. Diagnosis is common at a young age,and individuals with late diagnosis due to comorbidities have a shorter life expectancy. It causes dementia, epilepsy, myopathy, hearing loss, diabetes, and growth retardation. We present a patient with MELAS who was diagnosed late since it is a rare manifestation of diabetes with a different treatment than regular diabetes. Clinical Case A fifty-year-old female patient requested regulation of her blood sugar. She had type 2 diabetes for 20 years and hypertension, hyperlipidemia; she had a coronary bypass surgery three years ago and had been using a hearing implant for one year. She is under insulin treatment since 2018. Her 13-year-old daughter was just diagnosed with MELAS due to growth and development delays, and the m.3243AG mutation was discovered. She also screened for MELAS and found heteroplasmic m.3243A<G mutation. Her height was 143 cm, weight was 38 kg and BMI was 18.5 kg/m2. The patient was oriented and cooperative, but reluctant to answer questions. Her speech was slow, she was partial numbness, and she was not open to communication due to hearing loss, questions were always answered by her daughter. She exhibited a poor memory and calculation functions. She had muscle weakness in both extremities with a proximal muscles strength level of 3 and also described exercise intolerance. The patient did not have any seizures. She described a loss of hearing in the left ear and very poor hearing in the right ear. She had attacks of a migraine-like headache in left side of head and palpitation. Her medications included insulin glargine 1×22 units, insulin glulisine 3×8 units, coenzyme Q10 2×100 mg, arginine 3×2.5 grams, ranolazine 375 mg, perindopril 5 mg, sprinolactone 25 mg, metoprolol 50 mg, and rosuvastatin 20 mg. While Hba1c was 10.4 µg/dl, there were postprandial hyperglycemias with the highest 372 mg/dl and fasting hypoglycemias with the lowest 55 mg/dl in blood sugar follow-ups. The patient's treatment was arranged as 2×15 units of insulin degludec aspart and 1×8 units of insulin glulisine before lunch. Linagliptin was preferred instead of the weight-loss GLP-1 agonist to reduce mitochondrial stress in the patient with low BMI. Diabetic oral nutrition therapy was recommended to the malnourished patient. For cardiac evaluation, echocardiography and rhythm holter were requested. The patient was referred to the dementia outpatient clinic for memory and poor higher neurological function. Our patient had late diagnosis of MELAS with multiple complications including sensorineural deafness, a short stature and neurologic manifestations. Considering MELAS in diabetic patients with hearing loss, neurodegenerative findings, low body mass index and intolerant of metformin will significantly reduce the morbidity of the disease by enabling early diagnosis and treatment.

Association of Serum Liver Enzymes with Brain Amyloidopathy and Cognitive Performance.

Alzheimer's disease (AD) is characterized by amyloid-β (Aβ) plaque accumulation and neurofibrillary tangles in the brain. Emerging evidence has suggested potential interactions between the brain and periphery, particularly the liver, in regulating Aβ homeostasis. This study aimed to investigate the association of serum liver enzymes with brain amyloidopathy and cognitive performance in patients with complaints of cognitive decline. A total of 1,036 patients (mean age 74 years, 66.2% female) with subjective cognitive decline, mild cognitive impairment, AD dementia, and other neurodegenerative diseases were included using the Smart Clinical Data Warehouse. Amyloid positron emission tomography (PET) imaging, comprehensive neuropsychological evaluations, and measurements of liver enzymes, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, total bilirubin, and albumin, were assessed. After propensity score matching, logistic and linear regression analyses were used to investigate the associations between liver enzymes, amyloid status, and cognitive performance. Additionally, a machine learning approach was used to assess the classification performance of liver enzymes in predicting amyloid PET positivity. Lower ALT levels and higher AST-to-ALT ratios were significantly associated with amyloid PET positivity and AD diagnosis. The AST-to-ALT ratio was also significantly associated with poor memory function. Machine learning analysis revealed that the classification performance of amyloid status (AUC = 0.642) for age, sex, and apolipoprotein E ɛ4 carrier status significantly improved by 6.2% by integrating the AST-to-ALT ratio. These findings highlight the potential association of liver function on AD and its potential as a diagnostic and therapeutic implications.

Food Insecurity, Memory, and Dementia Among US Adults Aged 50 Years and Older

Despite existing federal programs to increase access to food, food insecurity is common among US older adults. Food insecurity may affect Alzheimer disease and Alzheimer disease-related dementias via multiple mechanisms, yet there is almost no quantitative research evaluating this association. To examine whether food insecurity in older adults is associated with later-life cognitive outcomes. This cohort study of US residents aged 50 years and older from the US Health and Retirement Study was restricted to respondents with food insecurity data in 2013 and cognitive outcome data between calendar years 2014 and 2018. Analyses were conducted from June 1 to September 22, 2023. Food insecurity status in 2013 was assessed using the validated US Department of Agriculture 6-item Household Food Security Module. Respondents were classified as being food secure, low food secure, and very low food secure. Outcomes were dementia probability and memory score (standardized to 1998 units), estimated biennially between 2014 and 2018 using a previously validated algorithm. Generalized estimation equations were fit for dementia risk and linear mixed-effects models for memory score, taking selective attrition into account through inverse probability of censoring weights. The sample consisted of 7012 participants (18 356 person-waves); mean (SD) age was 67.7 (10.0) years, 4131 (58.9%) were women, 1136 (16.2%) were non-Hispanic Black, 4849 (69.2%) were non-Hispanic White, and mean (SD) duration of schooling was 13.0 (3.0) years. Compared with food-secure older adults, experiencing low food security was associated with higher odds of dementia (odds ratio, 1.38; 95% CI, 1.15-1.67) as was experiencing very low food security (odds ratio, 1.37; 95% CI, 1.11-1.59). Low and very low food security was also associated with lower memory levels and faster age-related memory decline. In this cohort study of older US residents, food insecurity was associated with increased dementia risk, poorer memory function, and faster memory decline. Future studies are needed to examine whether addressing food insecurity may benefit brain health.

Emotion Regulation and Prospective Memory in Children with Autism Spectrum Disorder: An Empirical Investigation

Introduction: Autism spectrum disorder (ASD) has often been associated with emotion dysregulation and poor memory functions. While both these aspects are integral to daily life, understanding their relationship with individuals with ASD is critical. Previous research has indicated amplified emotional response, suggesting emotion dysregulation to be a core feature of ASD. Findings in the area of prospective memory (PM) yield inconsistent results. Therefore, this study aims to explore parental assessment of emotion regulation (ER) strategies and PM in children with ASD. Methods: This cross-sectional research was conducted using proxy reports by parents using snowball sampling between the ages of 5 and 12 years (n = 40) and analyzed using ANOVA. Results: The factorial ANOVA revealed that children with ASD exhibited significantly lower utilization of cognitive reappraisal strategies compared to the neurotypical group (F [1, 78] = 29.829, P < 0.001). In addition, significant main effects were observed for cue (F [1, 78] = 4.191, P = 0.044) and term (F [1, 78] = 35.669, P < 0.001). However, the main effect of memory was not found to be statistically significant (F [1, 78] = 3.194, P = 0.078). Furthermore, a substantial group effect was detected in the context of memory performance (F [1, 78] = 135.170, P < 0.01). Conclusion: The findings suggest that parent rating on ER and PM can adequately provide an insight into the actual performance of children.

Lower Intelligence Quotient and Larger Brain Volume in the Precuneus among Patients with Graves’ Disease

Abstract Objectives: Neuropsychiatric symptoms are related to hyperthyroidism. Whether global cognitive function is impaired is unclear. In this study, we intended to investigate whether patients with Graves’ disease (GD) are characterized by a lower intelligence quotient (IQ) and gray matter volume loss. Methods: We enrolled 36 patients with GD and 36 healthy controls. Intelligence quotient and other cognitive functions, such as memory and attention, were assessed. Magnetic resonance imaging (MRI) study was used to measure the gray matter volume for those study participants. Results: Significantly lower IQ scores (p < 0.001) and poor memory function (p < 0.05) were found among the patients with GD. We also found that patients with GD had a nonsignificant larger gray matter volume in the precuneus compared with that in healthy controls. Conclusion: The deficits on global and complex cognitive testing among patients with GD should be noted. We speculate that the larger gray matter volume in the precuneus might be due to compensation.

Prenatal ambient air pollutant mixture exposure and neurodevelopment in urban children in the Northeastern United States

Studies of prenatal air pollution (AP) exposure on child neurodevelopment have mostly focused on a single pollutant. We leveraged daily exposure data and implemented novel data-driven statistical approaches to assess effects of prenatal exposure to a mixture of seven air pollutants on cognitive functioning in school-age children from an urban pregnancy cohort. Analyses included 236 children born at ≥37 weeks gestation. Maternal prenatal daily exposure levels for nitrogen dioxide (NO2), ozone (O3), and constituents of fine particles [elemental carbon (EC), organic carbon (OC), nitrate (NO3-), sulfate (SO42-), ammonium (NH4+)] were estimated based on residential addresses using validated satellite-based hybrid models or global 3-D chemical-transport models. Children completed Wide Range Assessment of Memory and Learning (WRAML-2) and Conners' Continuous Performance Test (CPT-II) at 6.5±0.9 years of age. Time-weighted levels for mixture pollutants were estimated using Bayesian Kernel Machine Regression Distributed Lag Models (BKMR-DLMs), with which we also explored the interactions in the exposure-response functions among pollutants. Resulting time-weighted exposure levels were used in Weighted Quantile Sum (WQS) regressions to examine AP mixture effects on outcomes, adjusted for maternal age, education, child sex, and prenatal temperature. Mothers were primarily ethnic minorities (81% Hispanic and/or black) reporting ≤12 years of education (68%). Prenatal AP mixture (per unit increase in WQS estimated AP index) was associated with decreased WRAML-2 general memory (GM; β=-0.64, 95%CI=-1.40, 0.00) and memory-related attention/concentration (AC; β=-1.03, 95%CI=-1.78, -0.27) indices, indicating poorer memory functioning, as well as increased CPT-II omission errors (OE; β=1.55, 95%CI=0.34, 2.77), indicating increased attention problems. When stratified by sex, association with AC index was significant among girls, while association with OE was significant among boys. Traffic-related pollutants (NO2, OC, EC) and SO42- were major contributors to these associations. There was no significant evidence of interactions among mixture components. Prenatal exposure to an AP mixture was associated with child neurocognitive outcomes in a sex- and domain-specific manner.

Associations of sleep disturbances with cognitive function and plasma Alzheimer’s biomarkers in Chinese rural‐dwelling older adults: A population‐based study

AbstractBackgroundSleep disturbances have been associated with cognitive impairment, but their associations with plasma Alzheimer’s disease (AD) biomarkers have been rarely explored. We sought to investigate the relationships of self‐reported and cardiopulmonary coupling (CPC)‐assessed sleep disturbances, cognitive function, and plasma AD biomarkers among rural‐dwelling older adults in China.MethodThis population‐based cross‐sectional study included 1987 dementia‐free individuals (age ≥60 years, 55.0% women) who participated in the CPC‐substudy as part of the baseline assessments of the MIND‐China Study; of these, 830 had data on plasma Aβ42, Aβ40, total‐tau, and neurofilament light chain (NfL) that were measured using the single molecule array (SIMOA) technology. We collected data via face‐to‐face interviews, clinical examinations, and neuropsychological test. Sleep disturbances were assessed using the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), the self‐administered Berlin Questionnaire, and the ECG‐based CPC analysis. We used the neuropsychological test battery to assess memory, language, attention, and executive function. Data were analyzed using logistic and general linear regression models.ResultOf the 1987 participants, CPC‐measured total sleep time (TST) >8 hours/night (vs. 5‐8 hours) was significantly associated with a lower composite z‐score of memory (β = ‐0.080; 95% CI = ‐0.160 ‐ ‐0.001), language (‐0.114; ‐0.186 ‐ ‐0.042), attention (‐0.104; ‐0.175 ‐ ‐0.033), and executive function (‐0.117; ‐0.193 ‐ ‐0.041). Self‐reported poor sleep quality was associated with a lower composite z‐score of attention function (β = ‐0.077; 95% CI = ‐0.143 ‐ ‐0.011). Self‐reported excessive daytime sleepiness (EDS) was associated with a lower composite z‐score of memory (β = ‐0.217; 95% CI = ‐0.350 ‐ ‐0.084), language (‐0.182; ‐0.303 ‐ ‐0.061), and attention function (‐0.162; ‐0.282 ‐ ‐0.041). In the plasma biomarker subsample, CPC‐measured TST >8 hours/night was significantly associated with lower plasma Aβ42/Aβ40 ratio (β = ‐0.522; 95% CI = ‐0.764‐ ‐0.281) and higher plasma concentrations of Aβ40 (13.419; 6.515‐20.323), total‐tau (0.216; 0.071‐0.360), and NfL (0.071; 0.002‐0.140). There was no significant association between CPC‐measured apnea hypopnea index (AHI) and plasma AD biomarkers (P>0.05).ConclusionLong sleep duration and self‐reported EDS were associated with poor memory, language, and attention function among older adults, in which AD pathology and neurodegeneration may be the common pathways linking sleep disturbances with cognitive impairment.

A study on prevalence of anemia in school going Yanadi tribal children of Nellore District, Andhra Pradesh, India

Owing to the living condition, tribal community is at higher risk for diet-associated health disorders. The indigenous tribal populations like “The Yanadi”, residing in state of Andhra Pradesh in India. Being in the lower economic strata, they are deprived of proper food and access to basic health facilities is also constrained. Yanadi tribal children exhibit characteristic features of IDA, stunted growth, wasting and lower cognitive skills, which significantly affects their education. The study investigated the prevalence of anemia in 384 male Yanadi tribal schoolchildren aged 6-14 years and multiple approaches were adopted for survey-based data on social, economic and environment variables of the study-cohort was gathered along with anthropometric information. It was observed that huge majority of the tribal parents lacked primary school education and economic condition of such families is under dilapidating state, leading to consumption of improper food. Strikingly, 56% of the children exhibited the commonest symptom of anemia, pale conjunctiva. Overall analysis of the study participating children, following the WHO grading, close to 28% were found to be anemic and hemoglobin content (g/L) was observed to be close in both age groups, 11 to 14 years (11.889±1.123) and 7 to 10 years (11.734±1.309). Largely, the Yanadi tribal children projected cognitive impairment in the form of poor memory function (33%), down regulated cognitive functions (46%), and impaired attention functions (74.5%). It is somewhat relieving to see that anemia amongst Yanadi male children is not as severe as observed in children of other populations, as reported. However, the study projects out impaired cognitive and behavior skills amongst the participants, emphasizing the need of extending the study in a larger cohort.

Association of ambient air pollutants and cognitive impairment in a community‐dwelling elderly population: A four‐year cohort study

AbstractBackgroundLong‐term ambient air pollution has known to affect cognitive function. However, limited studies investigated the relationship between co‐exposure to ambient air pollutants and cognitive functions in non‐demented older adults. Therefore, this study aimed to explore this association in a community‐based prospective cohort study.MethodThis four‐year prospective cohort study is part of the ongoing Taiwan Initiative Geriatric Epidemiological Research (TIGER, 2011‐present) and included 286 non‐demented older adults between 2015‐2019. Ambient air pollution data were collected from 29 monitoring stations from Taiwan Environmental Protection Administration (TEPA) between 1994 and 2019. Global and domain‐specific (memory, attention, executive function, and language) cognitive functions were assessed using the Taiwanese version of Montreal Cognitive Assessment (MoCA‐T) and a battery of neuropsychological tests. The generalized linear mixed models were used to evaluate the association of co‐exposure to air pollutants with cognitive function adjusting for important covariates. Furthermore, we conducted stratified analyses by olfaction, known as an early marker of dementia.ResultExcept for PM2.5, the annual average exposure of the other five pollutants was below the TEPA standards. A 25‐year high‐level exposure of NO2 (≥ 27.7 ppb) was associated with good performance executive function (β = 0.25) over four years. For joint effect, high‐level (the highest tertile) PM2.5 with low to medium concentration level of NO2, CO, or SO2 were significantly associated with the poor performance of memory (β = ‐0.39 to ‐0.35). Similarly, high‐level PM2.5 with low to medium concentration level of NO2, PM10 with O3 were significantly associated with poor executive function (β = ‐0.28 to ‐0.19). In participants with normal olfaction, high co‐exposure level to PM2.5 and PM10, with CO, SO2, O3, and NO2 was significantly associated with poor memory and executive function (β = ‐0.55 to ‐0.30). No significant associations were found in participants with abnormal olfaction.ConclusionLong‐term low to medium‐level co‐exposure to NO2, CO, or SO2 and high‐level PM2.5 was associated with poor memory; co‐exposure to O3 with PM10 and co‐exposure to NO2 with PM2.5 was associated with poor executive function. A revision on exposure standards shall be considered to protect older adults at the preclinical phase of dementia.

Mesial-Temporal Epileptic Ripples Correlate With Verbal Memory Impairment

RationaleHigh frequency oscillations (HFO; ripples = 80–200, fast ripples 200–500 Hz) are promising epileptic biomarkers in patients with epilepsy. However, especially in temporal epilepsies differentiation of epileptic and physiological HFO activity still remains a challenge. Physiological sleep-spindle-ripple formations are known to play a role in slow-wave-sleep memory consolidation. This study aimed to find out if higher rates of mesial-temporal spindle-ripples correlate with good memory performance in epilepsy patients and if surgical removal of spindle-ripple-generating brain tissue correlates with a decline in memory performance. In contrast, we hypothesized that higher rates of overall ripples or ripples associated with interictal epileptic spikes correlate with poor memory performance.MethodsPatients with epilepsy implanted with electrodes in mesial-temporal structures, neuropsychological memory testing and subsequent epilepsy surgery were included. Ripples and epileptic spikes were automatically detected in intracranial EEG and sleep-spindles in scalp EEG. The coupling of ripples to spindles was automatically analyzed. Mesial-temporal spindle-ripple rates in the speech-dominant-hemisphere (left in all patients) were correlated with verbal memory test results, whereas ripple rates in the non-speech-dominant hemisphere were correlated with non-verbal memory test performance, using Spearman correlation).ResultsIntracranial EEG and memory test results from 25 patients could be included. All ripple rates were significantly higher in seizure onset zone channels (p < 0.001). Patients with pre-surgical verbal memory impairment had significantly higher overall ripple rates in left mesial-temporal channels than patients with intact verbal memory (Mann–Whitney-U-Test: p = 0.039). Spearman correlations showed highly significant negative correlations of the pre-surgical verbal memory performance with left mesial-temporal spike associated ripples (rs = −0.458; p = 0.007) and overall ripples (rs = −0.475; p = 0.006). All three ripple types in right-sided mesial-temporal channels did not correlate with pre-surgical nonverbal memory. No correlation for the difference between post- and pre-surgical memory and pre-surgical spindle-ripple rates was seen in patients with left-sided temporal or mesial-temporal surgery.DiscussionThis study fails to establish a clear link between memory performance and spindle ripples. This highly suggests that spindle-ripples are only a small portion of physiological ripples contributing to memory performance. More importantly, this study indicates that spindle-ripples do not necessarily compromise the predictive value of ripples in patients with temporal epilepsy. The majority of ripples were clearly linked to areas with poor memory function.

Dissociable impairments of verbal learning differentiate childhood risk profiles for schizophrenia

Poor verbal learning and memory function is well-documented among individuals with schizophrenia and those at clinical high-risk for psychosis. This study aimed to identify these impairments among children aged 9–12 years with different schizophrenia risk profiles (family history or antecedents of schizophrenia, each of higher[H] or lower[L] risk load) relative to typically developing peers. These three groups were recruited via community-screening, and differentiated for analysis into: typically developing children (TD = 45); children who had 1 first- or ≥2 second-degree affected relatives (FHxH = 16) or one second-degree relative (FHxL = 15); and children presenting multiple replicated antecedents of schizophrenia whose clinical symptoms persisted at 2- and/or 4-year follow-up (ASzH = 16) or remitted during follow-up (ASzL = 16). Verbal learning/memory measures assessed at baseline (age 9–12 years) included: (i) total recall; (ii) trial 1 recall; (iii) learning score; (iv) intrusions; (v) total words lost; and (vi) serial position patterns. Analyses of variance indicated that FHxH and ASzH youth demonstrated impaired total recall compared to TD and ASzL children and lost significantly more words between trials than TD and FHxL children. Learning score was impaired among both FHxH and FHxL relative to TD and ASzL children. Thus, among putatively at-risk children, total words recalled and lost distinguished those with higher risk load (by family history or persistent antecedent symptomology), whereas learning score indexed familial vulnerability. Follow-up of the sample is needed to determine the capacity of verbal learning deficits to predict later illness and provide a potential avenue for early remediation to improve clinical or functional outcomes.

Examining Subjective Aging through the Lens of the Caregiver Experience

Caregivers of individuals with Alzheimer’s disease and related dementia (ADRD) often experience burden that has been associated with poor physical and psychological health outcomes (Andren & Elmstahl, 2007; Zimmerman et al., 2018). However, very little research investigates how the caregiving experience may impact an individual’s subjective aging experience. Various aspects of subjective aging have been implicated in health outcomes and memory function (Brothers et al., 2017; Stephan, Sutin, Caudroit, & Terracciano, 2016). The purpose of this study was to investigate the differences in perceptions of subjective aging between caregivers and non-caregivers. Participants (N = 185) completed a survey assessing several aspects of subjective aging, including subjective age, or how old an individual feels, memory function, well-being, attitudes towards aging, and aging stereotypes. A series of independent t-tests indicated that there were significant differences between groups on subjective age (p = .013), and subjective memory function (p = .013). Caregivers (n = 93) reported feeling significantly older than their chronological age, reported significantly more subjective memory complaints, and also reported poorer subjective memory function when compared to the non-caregiver (n = 92) control group. Previous literature does suggest that older subjective age ratings are associated with poor subjective memory function, so these results are not necessarily surprising. However, these results suggest that caregiving for individuals with ADRD may negatively impact caregivers’ perceptions of their own aging experience, but not necessarily their perceptions about aging in general.

Examining Subjective Aging through the Lens of the Caregiver Experience

As people live longer, informal caregiving for family and friends is becoming increasingly common. Caregiver satisfaction with their role is now of greater importance to an increasing proportion of the U.S. population. Most research on caregivers has studied convenience samples, often restricted to caregivers of people with dementia. Various studies have examined the impact of caregiving on caregivers’ health but to our knowledge there are no qualitative studies of caregiving experiences from caregivers in population-based samples. This study investigated the impact of caregiving on participants who transitioned into a caregiving role while participating in a national population-based study. Participants were from the Caregiving Transitions Study, which is ancillary to the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study. We thematically analyzed responses from 150 caregivers providing care for multiple different conditions to an open-ended question asked at the time of enrollment and designed to encourage caregivers to share additional details about their caregiving experience. Four major themes were identified: cultural/family expectations; growth opportunities and reciprocity; stressors and challenges; and recommendations. Participants shared both positive and challenging experiences in their role as a family caregiver as well as the impact that these experiences had on their lives. Caregivers shared that one of the most important motivations for taking on this role was their sense of duty toward family. Caregivers also highlighted the positive impact of caregiving on their lives such as opportunities for personal growth, acquisition of new skills, and finding a sense of fulfillment and gratitude.

Sleep characteristics associated with mild cognitive impairment among rural‐dwelling older adults: The MIND‐China study

AbstractBackgroundSleep characteristics associated with mild cognitive impairment (MCI) and its subtypes are poorly defined in old age. We sought to characterize the sleep disturbances associated with MCI, subtypes of MCI, and specific cognitive domains among rural‐dwelling older adults in China.MethodThis population‐based cross‐sectional study included 4469 participants (age ≥65 years, 56.4% women) who were free of dementia and living in the rural communities in Yanggu County, Shandong. We collected data through interviews, clinical examinations, neuropsychological testing, and laboratory tests. We used the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale to evaluate various sleep parameters. Specific domain of cognitive function were assessed with the Auditory Verbal Learning Test (immediate recall, long‐delayed free recall, and long‐delayed recognition) for memory, the Semantic Verbal Fluency Test for language, the Digit Span Test for attention, and the Trail Making Test A &amp; B for executive function. MCI was diagnosed according to the Petersen’s criteria. Data were analysed using logistic and general linear regression models.ResultMCI was diagnosed in 1204 participants (940 with amnestic MCI [aMCI], 264 with nonamnestic MCI [naMCI]). The multivariable‐adjusted odds ratio (OR) of MCI was 1.45 (95% CI 1.14‐1.83) for sleep duration ≤4 hours/night (vs. &gt;6‐8 hours/night), 1.39 (1.12‐1.72) for sleep duration &gt;8 hours/night, 1.23 (1.06‐1.43) for poor sleep quality, 1.46 (1.25‐1.70) for low sleep efficiency, 1.29 (1.10‐1.50) for prolonged sleep latency, and 1.49 (1.17‐1.88) for excessive daytime sleepiness (EDS). These sleep characteristics were significantly associated with aMCI (multi‐adjusted OR range: 1.27‐1.46; p&lt;0.05). EDS was significantly associated with naMCI (multi‐adjusted OR 1.56 [1.04‐2.33]). In addition, short and long sleep duration, poor sleep quality, low sleep efficiency, prolonged sleep latency, and EDS were associated with worse memory function. Long sleep duration, low sleep efficiency, and EDS were associated with worse language function. Low sleep efficiency and EDS were associated with worse attention function. However, none of the examined sleep parameters was significantly associated with executive function.ConclusionShort and long sleep duration, poor sleep quality, low sleep efficiency, prolonged sleep latency, and EDS were associated with an elevated likelihood of MCI, especially aMCI and poor memory function.

Physically Active Lifestyle Is Associated With Attenuation of Hippocampal Dysfunction in Cognitively Intact Older Adults.

Alterations in hippocampal function have been shown in older adults, which are expressed as changes in hippocampal activity and connectivity. While hippocampal activation during memory demands has been demonstrated to decrease with age, some older individuals present increased activity, or hyperactivity, of the hippocampus which is associated with increased neuropathology and poor memory function. In addition, lower functional coherence between the hippocampus and core hubs of the default mode network (DMN), namely, the posteromedial and medial prefrontal cortices, as well as increased local intrahippocampal connectivity, were also demonstrated in cognitively intact older adults. Aerobic exercise has been shown to elicit neuroprotective effects on hippocampal structure and vasculature in aging, and improvements in cardiorespiratory fitness have been suggested to mediate these exercise-related effects. However, how these lifestyle factors relate to hippocampal function is not clear. Fifty-two cognitively intact older adults (aged 65–80 years) have been recruited and divided into physically active (n = 29) or non-active (n = 23) groups based on their aerobic activity lifestyle habits. Participants underwent resting-state and task-based fMRI experiments which included an associative memory encoding paradigm followed by a post-scan memory recognition test. In addition, 44 participants also performed cardiopulmonary exercise tests to evaluate cardiorespiratory fitness by measuring peak oxygen consumption (Vo2peak). While both groups demonstrated increased anterior hippocampal activation during memory encoding, a physically active lifestyle was associated with significantly lower activity level and higher memory performance in the recognition task. In addition, the physically active group also demonstrated higher functional connectivity of the anterior and posterior hippocampi with the core hubs of the DMN and lower local intra-hippocampal connectivity within and between hemispheres. Vo2peak was negatively associated with the hippocampal activation level and demonstrated a positive correlation with hippocampal-DMN connectivity. According to these findings, an aerobically active lifestyle may be associated with attenuation of hippocampal dysfunction in cognitively intact older adults.