Elderly Controls Research Articles

Prefrontal working memory activity predicts episodic memory performance: A neuroimaging study

Working memory (WM) and long term memory (LTM) are different neuropsychological processes, although distinction between these domains is an area of debate. LTM is thought to rely on hippocampal circuitry. Cognitive neuroscience models imply that WM processing may at least partially support LTM within regions of the prefrontal cortex (PFC). We sought to determine the association between PFC based WM processing and LTM in the visuospatial domain. In contrast to prior work, we aimed to query if WM was involved in learning and free recall trials as measured by standard neuropsychological tests of LTM. Forty-three older adults (24 with a diagnosis of amnestic Mild Cognitive Impairment and 19 elderly controls) were included in the analysis. Patients completed a fMRI task of visuospatial maintenance WM in which they were required to match a previously studied complex shape with one of two probes. Extent of activity in the right PFC during the WM task was tabulated for each patient. Hippocampal volume was quantified from T1 scans. On a separate day patients completed neuropsychological testing, including the Brief Visuospatial Memory Test- Revised (BVMT-R), which includes learning trials (total recall), delayed free recall, and recognition. Right PFC activity was associated with performance on BVMT-R total recall and delayed recall. Results from multiple regression showed that PFC activity explained an additional 9 % of the variance in memory performance above right hippocampal volume. These findings suggest that PFC processing that supports WM (including stimuli maintenance, retrieval, and selection) are also involved in LTM learning and recall.

Overview of Motivation for Elderly Services for Control and Satisfaction in Polyclinic RSST Klaten

<em>Background: Elderly during the examination were hoping to get good health care. Elderly will be motivated to check when he is satisfied with the services provided by health workers in hospitals. The purpose of this study was to Study the picture of the elderly to check the level of motivation and satisfaction in the service of RSST Klaten Policlinic. The design used in this study is Despriptif. The population is all the elderly who checked up in RSST Klaten. Samples are 96 respondents and taken with consecutive sampling technique. The variable in this study was to examine elderly motivation and service satisfaction. Data were collected with a structured interview, then processed based on the frequency distribution. Methods: The design of this study is descriptive. This study was conducted On September 1 - 30, 2019. Variable in this research is Elderly Motivation For Control and Service Satisfaction. In this research The population is all elderly ones Control at RSST Klaten Polyclinic Based on data from Medical Record Hospital SOERADJI TIRTONEGORO during the month August 2019 number of elderly patients who Control at RSST Klaten Polyclinic As many as 598 patients. Result The results of the study of 96 The respondent got none Respondents who have a level Less motivation, motivation level Quite as much as 2 respondents (2%) And high level of motivation as much 94 respondents (98%). Conclusions : Level of elderly motivation for Control at Polyclinic RSST Klaten majority is high As many as 94 respondents (98%). This matter Caused by age, type Sex and education of respondents and Satisfaction of the ministry Received patients at Polyclinic RSST Klaten.</em>

The complement cascade in Alzheimer's disease: a systematic review and meta-analysis.

Genetic evidence implicates a causal role for the complement pathway in Alzheimer's disease (AD). Since studies have shown inconsistent differences in cerebrospinal fluid (CSF) and peripheral blood complement protein concentrations between AD patients and healthy elderly, this study sought to summarize the clinical data. Original peer-reviewed articles measuring CSF and/or blood concentrations of complement or complement regulator protein concentrations in AD and healthy elderly control (HC) groups were included. Of 2966 records identified, means and standard deviations from 86 studies were summarized as standardized mean differences (SMD) by random effects meta-analyses. In CSF, concentrations of clusterin (NAD/NHC = 625/577, SMD = 0.53, Z8 = 8.81, p < 0.005; I2 < 0.005%) and complement component 3 (C3; NAD/NHC = 299/522, SMD = 0.45, Z3 = 3.21, p < 0.005; I2 = 68.40%) were significantly higher in AD, but differences in C1q, C-reactive protein (CRP), serum amyloid protein (SAP), and factor H concentrations were not significant. In peripheral blood, concentrations of CRP were elevated in AD (NAD/NHC = 3404/3332, SMD = 0.44, Z43 = 3.43, p < 0.005; I2 = 93.81%), but differences between groups in C3, C4, C1-inhibitor, SAP, factor H and clusterin concentrations were not significant,and inconsistent between studies. Of 64 complement pathway proteins or regulators in the quantitative synthesis, trends in C1q, factor B, C4a, and late-stage complement pathway components (e.g. C9) in blood, C4 in CSF, and the membrane attack complex in blood and CSF, might be investigated further. The results collectively support elevated complement pathway activity in AD, which was best characterized by increased CSF clusterin concentrations and less consistently by CSF C3 concentrations. Complement activity related to anADdiagnosis was not reflected consistently by the peripheral blood proteins investigated.

Evaluation of Peripheral Immune Dysregulation in Alzheimer's Disease and Vascular Dementia.

Immune dysregulation has been observed in the brain and blood of patients with Alzheimer's disease (AD). However, a convenient assay to evaluate peripheral immune dysregulation in AD has not been developed, partly due to the inconsistent observations from different studies. We hypothesized that peripheral immune dysregulation may only exist in a subpopulation of AD patients; therefore it may be valuable to identify this subpopulation with a convenient assay. Along this line, we selected 14 candidate genes based on our analysis of microarray data on peripheral blood of AD and other diseases. We used RT-qPCR to examine the expression of these 14 genes in a cohort of 288 subjects, including 74 patients with AD, 64 patients with mild cognitive impairment (MCI), 51 patients with vascular dementia (VaD), and 99 elderly controls with no cognitive dysfunction/impairment. Seven of these 14 genes displayed significant difference in group comparison. Switching from group comparison to individualized evaluation revealed more in-depth information. First, there existed a wide dynamic range for the expression of these immune genes in peripheral blood even within the control group. Second, for the vast majority of the patients (AD, VaD, and MCI patients), the expression of these genes fell within the dynamic range of the control group. Third, a small portion of outliers were observed in the patient groups, more so in the VaD group than that in the AD or MCI groups. This is our first attempt to conduct personalized evaluation of peripheral immune dysregulation in AD and VaD. These findings may be applicable to the identification of peripheral immune dysregulation in AD and VaD patients which may lead to tailored treatment toward those patients.

An Integrated MCI Detection Framework Based on Spectral-temporal Analysis

Aiming to differentiate between mild cognitive impairment (MCI) patients and elderly control subjects, this study proposes an integrated framework based on spectral-temporal analysis for the automatic analysis of resting-state electroencephalogram (EEG) recordings. This framework firstly eliminates noise by employing stationary wavelet transformation (SWT). Then, a set of features is extracted through spectral-temporal analysis. Next, a new wrapper algorithm, named three-dimensional (3-D) evaluation algorithm, is proposed to derive an optimal feature subset. Finally, the support vector machine (SVM) algorithm is adopted to identify MCI patients on the optimal feature subset. Decision tree and K-nearest neighbors (KNN) algorithms are also used to test the effectiveness of the selected feature subset. Twenty-two subjects are involved in experiments, of which eleven persons were in an MCI condition and the rest were elderly control subjects. Extensive experiments show that our method is able to classify MCI patients and elderly control subjects automatically and effectively, with the accuracy of 96.94% achieved by the SVM classifier. Decision tree and KNN algorithms also achieved superior results based on the optimal feature subset extracted by the proposed framework. This study is conducive to timely diagnosis and intervention for MCI patients, and therefore to delaying cognitive decline and dementia onset.

Five Personality Traits in Late-onset Depression in Hong Kong.

This study aimed to examine the association between five personality traits and late-onset depression in Hong Kong older people. This cross-sectional study included a convenience sample of 40 older people with late-onset depression (LOD) and 54 non-depressed elderly controls. The patients were assessed using the NEO Five Factor Inventory (for personality), the Hamilton Depression Rating Scale (for depression severity), the Mini-Mental State Examination (for cognitive function), the Lawton Instrumental Activities of Daily Living (for functioning), and the Cumulative Illness Rating Scale (for number of physical illnesses). The LOD group had a higher Hamilton Depression Rating Scale score (18.9 vs 3.7, p < 0.001), lower Mini Mental State Examination score (24.9 vs 26.4, p = 0.004), and lower Instrumental Activities of Daily Living scale score (21.9 vs 23.7, p = 0.013). On the NEO Five Factor Inventory, the LOD group had a higher neuroticism score (30.7 vs 17.5, p < 0.001) and lower scores on extraversion (19.0 vs 26.4, p < 0.001), openness (18.9 vs 21.5, p = 0.026), and conscientiousness (29.1 vs 33.8, p < 0.001). Neuroticism was the only significant predictor of LOD (odds ratio = 2.325, p = 0.001) and the only significant factor associated with depression severity (β = 0.581, p = 0.003). The personality trait of neuroticism is associated with LOD and its severity. Assessment of personality traits should be included in the assessment of people with depression.

Incremental load training improves renal fibrosis by regulating the TGF‑β1/TAK1/MKK3/p38MAPK signaling pathway and inducing the activation of autophagy in aged mice.

Recent studies have confirmed that kidney tissue fibrosis is closely linked to the natural aging of organs. One of its major characteristics is the reduction of autophagic activity. However, to date, few studies have assessed whether incremental load training is able to improve the occurrence of renal fibrosis caused by natural aging and the underlying mechanisms. In the present study involving male C57/BL mice, an elderly exercise group (OY group) was subjected to progressive load-increasing rotary-bar training (5 days/week, lasting for 6 weeks), with an elderly control group (OC group) and a young control group (YC group) used as controls. Renal fibrosis and autophagy-associated indicators were assessed by Masson's staining, reverse transcription-quantitative PCR analysis, western blotting, immunofluorescence and transmission electron microscopy. The results suggested that collagen deposition in the basal part of the renal tubular epithelium and glomeruli in the OY group was significantly lower than that in the OC group. In the OC group, the protein expression levels of E-cadherin, Beclin 1 and light chain 3 were significantly decreased, and increases in α-smooth muscle actin-positive signals were observed in the glomerular matrix and renal capsule wall. Furthermore, the expression of transforming growth factor (TGF)-β1 and its downstream signaling molecules TGF-β-activated kinase 1 (TAK1), mitogen-activated protein kinase (MAPK) kinase (MKK3) and p38MAPK were downregulated following training. The present study confirmed that incremental load training may improve renal fibrosis in aged mice by regulating the TGF-β1/TAK1/MMK3/p38MAPK signaling pathway and inducing the activation of autophagy to reduce the synthesis of extracellular matrix and delay the epithelial-mesenchymal transition. The present study provides a novel experimental basis for the intervention of incremental load training to prevent senile renal fibrosis.

The Prevalence of Zinc Deficiency among Men with and without Prostate Cancer in Port Harcourt, Nigeria

Background: Zinc deficiency is reportedly common and influences prostate cancer (PCa) incidence among elderly males. Hence, this study was designed to determine the prevalence of zinc deficiency among Nigerian males with PCa.Materials and Methods: This was a descriptive case–control study among 220 PCa patients and 220 age-matched controls. Clinical and laboratory variables were obtained and evaluated among both study groups. Analysis of serum PSA and plasma zinc was done under standard protocols.Results: No age difference (cases: 69.73 ± 7.72 vs controls: 68.97 ± 7.32; P > 0.05) was observed among both study groups. Prevalence of zinc deficiency among PCa and control groups was 69.1% and 21.8%, respectively. Zinc deficiency was more prevalent among the elderly PCa patients (n = 119; 78.3%) compared to elderly controls. Higher proportion (n = 136; 89.5%) of zinc-deficient PCa patients presented with moderate-severe PCa disease. Elderly PCa patients (n = 119; 81.0%) predominated among those exhibiting moderate-severe PCa disease. Inverse relationship between zinc and age was more pronounced among the PCa patients (Beta= −0.454; P < 0.001) than the controls (Beta= −0.343; P ≤ 0.001).Conclusion: The study findings indicate a significant burden of zinc deficiency associated with adverse outcome of PCa among elderly males with the disease. Zinc deficiency may serve as a therapeutic target or diagnostic marker in elderly males with PCa.

Assessment of Long Term Metabolic Effects of Atypical Antipsychotics in Schizophrenia Patients

Abstract Background and aims. Patients with schizophrenia have a shorter life expectancy than normal population partially due to the metabolic side effects of antipsychotic treatment. The aim of this study is to evaluate the long-term evolution of the metabolic syndrome in chronic schizophrenia patients on fixed second generation antipsychotics (SGA). Material and method. The components of metabolic syndrome were evaluated repeatedly in a minimum 6 months and maximum 2 years follow-up period. The presence of metabolic syndrome (MetS) and metabolic risk scores (cMetS) according to National Cholesterol Education Program Adult Treatment Panel III were calculated and compared in time. In the prevalence, incidence and normalization logistic regression studies included all the known risk factors together with the follow-up period. Finally, all these rates were compared depending on the type of SGA. Results. Only cMetS, waist circumference and diastolic blood pressure presented significant increase in the follow-up period which was in average 385.5 days. The prevalence of MetS at base-line was 39.4%, which increased to 48.5% after the follow-up period. The calculated incidence of 30% was associated with a 23.1% rate of normalization. Logistic regression studies revealed as independent risk factors the age and base-line cMetS/weight for incidence and for normalization. In the aripiprazole group the normalization rate exceeded the incidence rate (33.3% vs 20%). Conclusions. The results emphasize the highly dynamic character of the metabolic syndrome even in chronic schizophrenia patients with fixed SGA regimen. The normalization of MetS is a possibility that should not ignored. The age and weight continue to remain independent risk factors, thus close monitoring in elderly and strict weight control plan are necessary. Aripiprazole showed better safety profile, but more extensive studies are required for definitive conclusions.

A Novel MRI Compatible Balance Simulator to Detect Postural Instability in Parkinson's Disease.

Background: Postural instability is a debilitating and largely treatment-resistant symptom of Parkinson's disease (PD). A better understanding of the neural substrates contributing to postural instability could lead to new targets for improved pharmacological and neurosurgical interventions. However, investigating these neural substrates necessitates the use of functional MRI scanners, which are almost exclusively horizontally-based.Objective: We aimed to develop, and validate the use of, an MRI compatible balance simulator to study static and dynamic balance control in PD patients and elderly controls.Methods: Our MRI compatible balance simulator allowed participants to actively balance an inverted pendulum by activating postural muscles around the ankle joint while supine. Two studies were performed to compare static and dynamic balance performance between upright stance and simulated stance in PD patients and controls. Study 1 (14 PD; 20 controls) required participants to maintain static balance during upright and simulated stance for 120 s with eyes open and closed. In study 2 (20 PD; 22 controls) participants repeated the static balance task (80 s, eyes closed only), and also completed a dynamic balance task which required maintaining balance while experiencing random anterior-posterior perturbations applied to the trunk/pendulum. Postural sway of the body/pendulum was measured using an angular velocity sensor (SwayStarTM, study 1) and Optotrak motion capture (study 2). Outcome measures were amplitude and frequency of center of mass sway for static balance, and peak and time-to-peak of center of mass displacement and velocity for dynamic balance.Results: PD patients had larger sway amplitude during both upright and simulated static balance compared to controls. PD patients had larger peak and time-to-peak sway, and larger time-to-peak sway velocity, during simulated, but not upright, dynamic balance compared to controls.Conclusions: Deficits in static and dynamic balance control can be detected in PD patients using a novel MRI compatible balance simulator. This technique allows for functional neuroimaging to be combined with balance-relevant tasks, and provides a new means to create insights into the neural substrates contributing to postural instability in PD.

Changes of white matter integrity and structural network connectivity in nondemented cerebral small‐vessel disease

Previous studies have found widespread impairment of white matter (WM) integrity and disruption of structural network connectivity in cerebral small-vessel disease, but have not evaluated these changes jointly in nondemented patients. To jointly investigate the microstructural impairment of WM and the related alterations of structural network topology in nondemented cerebral small-vessel disease (CSVD-ND). Prospective. Thirty-seven CSVD-ND patients and 34 elderly controls, who were age-, sex-, and education-matched. 3.0T/diffusion tensor imaging (DTI). Clinical characteristics, lacunar infarct, and white matter hyperintensity (WMH) was assessed. A multiatlas likelihood fusion (MALF) algorithm was used for DTI-based brain segmentation and network node defining. Then the alterations of WM integrity and structural network topology were investigated jointly. Student's t-test, chi-square test, Mann-Whitney U-test, linear regression, Pearson correlation, and multiple comparison correction. Decreased fractional anisotropy and increased trace values were observed in predefined structures (P < 0.05, familywise error rate-corrected), including major commissural fibers, projection fibers, and some association fibers. Topologically, both groups showed small-worldness. CSVD-ND patients showed reduced global and local efficiency (P < 0.001). Despite widespread impairment of WM integrity, CSVD-ND patients only showed reduced nodal efficiency in the right superior occipital gyrus and the right lingual gyrus (P < 0.05, familywise error rate-corrected). The nodal local efficiency of the right precuneus was associated with the processing speed after adjusting the effect of lacunar infarct and WMH (r = -0.499, P = 0.038). WM integrity was widely impaired in nondemented CSVD patients but structural network connectivity was relatively preserved. DTI may potentially provide information for the pathophysiology of CSVD in the nondemented phase. 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2020;51:1162-1169.

High Availability of the α7-Nicotinic Acetylcholine Receptor in Brains of Individuals with Mild Cognitive Impairment: A Pilot Study Using 18F-ASEM PET.

Emerging evidence supports a hypothesized role for the α7-nicotinic acetylcholine receptor (α7-nAChR) in the pathophysiology of Alzheimer's disease. 18F-ASEM (3-(1,4-diazabicyclo[3.2.2]nonan-4-yl)-6-18F-fluorodibenzo[b,d]thiophene 5,5-dioxide) is a radioligand for estimating the availability of α7-nAChR in the brain in vivo with PET. Methods: In this cross-sectional study, 14 patients with mild cognitive impairment (MCI), a prodromal stage to dementia, and 17 cognitively intact, elderly controls completed 18F-ASEM PET. For each participant, binding in each region of interest was estimated using Logan graphical analysis with a metabolite-corrected arterial input function. Results: Higher 18F-ASEM binding was observed in MCI patients than in controls across all regions, supporting higher availability of α7-nAChR in MCI. 18F-ASEM binding was not associated with verbal memory in this small MCI sample. Conclusion: These data support use of 18F-ASEM PET to examine further the relationship between α7-nAChR availability and MCI.

Alterations in White Matter Network and Microstructural Integrity Differentiate Parkinson's Disease Patients and Healthy Subjects.

Parkinson’s disease (PD) is a neurodegenerative disease, neuropathologically characterized by progressive loss of neurons in distinct brain areas. We hypothesize that quantifiable network alterations are caused by neurodegeneration. The primary motivation of this study was to assess the specific network alterations in PD patients that are distinct but appear in conjunction with physiological aging. 178 subjects (130 females) stratified into PD patients, young, middle-aged and elderly healthy controls (age- and sex-matched with PD patients), were analyzed using 3D-T1 magnetization-prepared rapid gradient-echo (MPRAGE) and diffusion weighted images acquired in 3T MRI scanner. Diffusion modeling and probabilistic tractography analysis were applied for generating voxel-based connectivity index maps from each seed voxel. The obtained connectivity matrices were analyzed using graph theoretical tools for characterization of involved network. By network-based statistic (NBS) the interregional connectivity differences between the groups were assessed. Measures evaluating local diffusion properties for anisotropy and diffusivity were computed for characterization of white matter microstructural integrity. The graph theoretical analysis showed a significant decrease in distance measures – eccentricity and characteristic path length – in PD patients in comparison to healthy subjects. Both measures as well were lower in PD patients when compared to young and middle-aged healthy controls. NBS analysis demonstrated lowered structural connectivity in PD patients in comparison to young and middle-aged healthy subject groups, mainly in frontal, cingulate, olfactory, insula, thalamus, and parietal regions. These specific network differences were distinct for PD and were not observed between the healthy subject groups. Microstructural analysis revealed diffusivity alterations within the white matter tracts in PD patients, predominantly in the body, splenium and tapetum of corpus callosum, corticospinal tract, and corona radiata, which were absent in normal aging. The identified alterations of network connectivity presumably caused by neurodegeneration indicate the disruption in global network integration in PD patients. The microstructural changes identified within the white matter could endorse network reconfiguration. This study provides a clear distinction between the network changes occurring during aging and PD. This will facilitate a better understanding of PD pathophysiology and the direct link between white matter changes and their role in the restructured network topology.

Adaptive changes in foot placement for split-belt treadmill walking in individuals with stroke

BackgroundAdaptation to split-belt treadmill walking differs between individual stroke survivors. Many discussions only address spatiotemporal parameters that are related to movement, and the changes in interlimb spatiotemporal parameters as a consequence of adaptation are poorly understood. ObjectivesTo investigate symmetry of the center of pressure (CoP) position relative to the center of mass (CoM), and ascertain whether this can be used to identify differences in adaptation of interlimb spatiotemporal parameters among stroke survivors during split-belt walking. MethodsTwenty-two chronic post-stroke patients and nine elderly controls walked in tied- then split-belt (2:1 ratio of fast:slow) conditions. Spatiotemporal parameters were compared within groups to assess symmetry of the CoM-CoP angle at foot contact. ResultsAsymmetry of the CoM-CoP angle was associated with asymmetry of spatiotemporal parameters. Re-establishment of symmetry of CoM-CoP angle was reflected in re-established symmetry of spatiotemporal parameters in post-stroke and control participants. ConclusionsPost-stroke patients who re-establish symmetry of the COM-COP angle are able to adapt their walking for split-belt perturbation. This suggests that predictively symmetric foot placements on the fast and slow sides are necessary for adaptation in walking. Symmetrical foot placement is achieved by interlimb coordination and may contribute to dynamic stability.

Electrophysiological evidence of altered facial expressions recognition in Alzheimer’s disease: A comprehensive ERP study

ObjectivesThe present study aims to evaluate the amplitude and latency of event-related potentials (ERPs) P100, N170, VPP and N230 in individuals with Alzheimer's disease (AD) compared to healthy elderly controls, using a passive viewing task of emotional facial expressions. MethodsTwenty-four individuals with mild to moderate AD and 23 demographically matched healthy elderly controls were included in the study. ERP P100, N170, VPP and N230 amplitude and latency values were compared between groups. ResultsThe categorization of emotional facial expressions was intact; yet, increased P100 amplitude and latency, decreased N170 amplitude, and increased VPP amplitude were observed in AD compared to controls. Increased N230 amplitude and latency were observed in response to angry expressions, while neutral expressions elicited decreased amplitude and latency. ConclusionsIncreased P100 amplitude and latency may reflect reduced amygdala volume and disruptions in the visual system, while decreased N170 and increased VPP amplitudes may reflect impaired perceptual processing, mitigated by a greater involvement of prefrontal areas for task performance in AD. SignificanceThis study is the first to report a complex pattern of ERPs to emotional facial expressions in individuals with AD.

A Clinically Applicable Interactive Micro and Macro-Sleep Staging Algorithm for Elderly and Patients with Neurodegeneration.

Elderly and patients with neurodegenerative diseases (NDD) often complain about sleep problems and show altered sleep structure. Automated algorithms for efficient and specific sleep staging are needed. We propose a new algorithm using only one electroencephalographic and two electrooculographic channels to score wakefulness, rapid eye movement (REM) sleep and non-REM sleep in a cohort of elderly healthy controls (HC), patients with Parkinson's disease (PD), isolated REM sleep behavior disorder (iRBD), considered the prodromal stage of PD, and patients with PD and RBD (PD+RBD). The proposed method scores both standard 30-s epochs (macro-staging) and 5-s mini-epochs (micro-staging), whose evaluation may help to better understand sleep micro-structure. Moreover, the algorithm is interactive, as it labels the classified sleep epochs as either certain or uncertain, so that experts can manually review the uncertain ones. The algorithm performances were evaluated for macro-sleep staging, where it achieved overall accuracies of 0.87±0.05 in 41 HC, 0.86±0.10 in 57 PD, 0.76±0.10 in 31 iRBD and 0.77±0.10 in 30 PD+RBD patients when all 30-s epochs were considered. The accuracies increased to 0.91±0.05, 0.90±0.08, 0.85±0.09, 0.88±0.08 respectively when considering only the certain ones. The epochs labeled as uncertain were 9.95±4.15%, 11.13±7.86%, 18.39±7.38% and 18.90±8.00% in HC, PD, iRBD and PD+RBD respectively. The proposed interactive micro and macro sleep staging algorithm can be used in clinics to reduce the burden of manual sleep staging in elderly and patients with NDD.

A MEG study of the neural substrates of semantic processing in semantic variant primary progressive aphasia

ABSTRACTDespite a well-documented pattern of semantic impairment, the patterns of brain activation during semantic processing in semantic variant primary progressive aphasia (svPPA) still remain poorly understood. In the current study, one svPPA patient (EC) and six elderly controls carried out a general-level semantic categorization task while their brain activity was recorded using magnetoencephalography (MEG). Despite similar behavioral performance, EC showed hyperactivation of the left inferior temporal gyrus (ITG) and right anterior temporal lobe (ATL) relative to controls. This suggests that periatrophic regions within the ATL region may support preserved semantic abilities in svPPA.

LOWER PLATELET COUNT AND DECREASED MEAN PLATELET VOLUME IN PATIENTS WITH ALZHEIMER’S DISEASE

Platelets are the major players in hemostasis, but are also involved in thrombosis, inflammation and tissue repair. Platelets are generally accepted as a suitable model for Alzheimer's disease (AD). In the present study serum platelet count, mean platelet volume (MPV), platelet distribution width (PDW) and plateletcrit (PCT) in patients with Alzheimer disease were analyzed and compared with controls. Platelet count and indices were evaluated in 130 patients with AD (Mean age 71.3±7.7 years, range 55–85 years, 65 women), (DSM-IV; NINCDS-ADRDA criteria); recruited in a community elderly in Skikda-Algeria (2016-2018); and in 130 elderly controls, (Mean age 69.8±7.8 years, range 55–85 years, 65 women). We assessed the relation between these platelet parameters and the odds ratio (OR) for AD. Correlation with dementia severity (Clinical dementia rating-global score, and mini mental status examination), was also examined. The mean serum platelet count was 220.5±44.7x109/L (Range 148x109-354x109) among cases, and 240.1±49.9x109/L (Range 155x109-396x109) among controls, (p= 0.0009). By gender, the difference between cases and controls was significant both in men 218.3±50.2x 109/L vs. 236.8±52.4x109/L respectively, p=0.041; and in women 222.7±38.7x109/L vs. 243.4±47.4x109/L, p= 0.007. The odds ratio [95 percent confidence interval] of AD for the highest tertile of platelet count compared to the lowest tertile was 0.428 [0.234–0.782], p= 0.006. This association was significant both in men OR: 0.3175 [0.1316–0.7659], p=0.017, and in women OR: 0.2663 [0.1102–0.6440], p=0.003. MPV was significantly lower in men cases compared to controls 9.04±0.8 femtoliter (Range 7.3-11.4) vs.9.34±0.9 femtoliter (Range 7.8-11.6) respectively; p=0.045. Mean plateletcrit was decreased in AD group compared to control 0.202±0.03% (Range 0.120-0.324) vs. 0.216±0.05% (Range 0.129-0.360), p=0.003. PDW was similar, AD: 13.2±1.2%, control: 13.4±1.5%. Platelet count and indices did not correlate significantly with dementia severity. These findings show that Alzheimer's disease patients have lower platelet count and lower plateletcrit (Within normal range) compared to controls. Subjects in the low normal range of platelet count have an increased risk for developing Alzheimer's disease. Furthermore a lower MPV (within normal range) was also found in AD men. Taken together, these data suggest a key role for circulating platelets in Alzheimer's disease.

P1‐227: DEFICITS IN EXECUTIVE FUNCTION IN AMNESTIC MILD COGNITIVE IMPAIRMENT: EVENT‐RELATED POTENTIALS STUDY DURING STROOP COLOR‐WORD TASK

Previous investigations showed that Alzheimer's disease (AD)-related executive function deficits start near the beginning of mild cognitive impairment (MCI) phase of itself. The study aimed to explore deficits in executive function in amnestic MCI (aMCI) with Event-Related Potentials (ERPs) study. The ERP data were measured and analyzed in 30 aMCI and 38 healthy elderly controls (HEC) during Stroop Color-Word Task (SCWT). The study indicated that aMCI patients showed decreased accuracy (ACC) and delayed reaction time (RT) in incongruent condition, compared to HEC (all p < 0.05). Additionally, aMCI patients showed greater N450 amplitudes of a difference wave between ERPs elicited by incongruent and congruent stimuli at Fz electrode, compared to HEC (all p < 0.05). Moreover, standardized low-resolution brain electromagnetic tomography analysis (sLORETA) study showed a hyperactivation in the left inferior parietal lobule (IPL) in the contrast for the incongruent condition relative to the congruent condition, compared to HEC during N450 time range (p < 0.05). The study showed deficits in conflict processing in aMCI with an ERP study. And the deficits might derive from the left IPL. Hence, the study demonstrated that ERP with SCWT was a sensitive biomarker for recognizing aMCI patients from HEC.

Awareness of olfactory dysfunction in Parkinson's disease.

Olfactory impairment is a very common symptom in Parkinson's disease (PD). However, individuals often overestimate their ability to smell. Hyposmia and metacognitive errors are also related to aging, depression, male gender and cognitive impairment. The current study investigated the awareness of olfactory functioning in PD and the influence of additional factors. A sample of 124 nondemented PD patients and 154 elderly controls was assessed with the Sniffin' Sticks Odor Identification Test (OIT) and the Subjective Olfactory Capability (SOC) domain of the Assessment of Self-Reported Olfactory Functioning and Olfaction-Related Quality of Life, additional to measures of depressive symptoms, verbal memory and executive functioning. Olfactory awareness groups were formed by means of the cut-offs of the OIT and the SOC. Significant correlations between the OIT and the SOC were moderate in participants with PD and small in controls. Of all PD patients, 52% overrated their sense of smell while 27% correctly identified themselves as being hyposmic, as opposed to corresponding 6% and 1% of healthy elderly. Overrating and aware of being hyposmic participants with PD showed worse executive functions than PD patients who were objectively and subjectively normosmic. The findings imply that, although people with PD are aware of hyposmia to some extent, the majority is affected by overestimation of the ability to smell, making self-reported functioning an unreliable source of information. Moreover, reduced odor identification and impaired executive functioning might underlie the same pathological changes within the brain and could serve as a marker for cognitive impairment in PD. (PsycINFO Database Record (c) 2019 APA, all rights reserved).