Frontiers in Aging Neuroscience最新文献

{"title":"Cortical activation in elderly patients with Alzheimer's disease dementia during working memory tasks: a multichannel fNIRS study.","authors":"Nairong Ruan, Xingxing Li, Ting Xu, Zheng Zhao, Xi Mei, Chengying Zheng","doi":"10.3389/fnagi.2024.1433551","DOIUrl":"10.3389/fnagi.2024.1433551","url":null,"abstract":"<p><strong>Objective: </strong>This study aimed to investigate cortical activation and functional connectivity in the cortex during working memory (WM) tasks in patients with Alzheimer's disease (AD) using functional near-infrared spectroscopy (fNIRS).</p><p><strong>Methods: </strong>A total of 17 older adults with AD and 17 cognitively normal (CN) participants were recruited. fNIRS was utilized to monitor oxygenated hemoglobin (HbO) concentrations in the frontotemporal lobe, while participants performed WM tasks to examine WM impairments in subjects with AD. Student's t-test for continuous variables and the chi-square test for categorical variables were used to compare the clinical and HbO variables between the AD and CN groups. Functional connectivity was analyzed using Pearson's correlation coefficient between the time series of each channel-to-channel pair.</p><p><strong>Results: </strong>The changes in HbO concentrations and cortical activations during the WM task showed that the HbO concentration curve of the CN group was higher than that of the AD group during the encoding and maintenance phases of the WM task. Although in the brain region scale, there were no significant differences in average HbO concentrations between the two groups, many channels located in the frontal and temporal lobes showed significant differences (<i>p</i> < 0.05) in the average HbO (channels 7 and 32) and slope HbO values (channels 7, 8, 9, 23, 30, 34, and 38) during the WM task. The average functional connectivity of the AD group was significantly lower than that of the CN group (<i>p</i> < 0.05). The functional connectivity was stronger in the frontopolar (FP) region than in other areas in both groups.</p><p><strong>Conclusion: </strong>This study revealed there were significant differences in HbO concentration in older adult patients with AD compared to CN during the WM task. The characteristics of HbO measured by the fNIRS technique can be valuable for distinguishing between AD and CN in older adults.</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1433551"},"PeriodicalIF":4.1,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11461194/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancement of cognitive function in mice with Alzheimer's disease through hyperbaric oxygen-induced activation of cellular autophagy.","authors":"Qian-Qian Fan, Yong-Min Chen, Yong-Sen Fu, Xiao-Shan Li, Ji Zeng, Shao-Zhen Bian, Bin-Bin Li, Zhen-Hua Song","doi":"10.3389/fnagi.2024.1418081","DOIUrl":"10.3389/fnagi.2024.1418081","url":null,"abstract":"<p><strong>Objective: </strong>In this study, we examined the effectiveness of hyperbaric oxygen (HBO) therapy in ameliorating cognitive deficits in mice with Alzheimer's disease (AD), while also assessing its impact on the autophagic pathway within the context of AD.</p><p><strong>Methods: </strong>20 double-transgenic mice expressing the amyloid precursor protein and presenilin 1 (APP/PS1) were purposefully selected and randomly assigned to groups A and B. Concurrently, 20 C57BL/6 mice were chosen and randomly categorized into groups C and D, each consisting of 10 mice. Mice in groups B and D received HBO treatment. The Morris water maze assay was used to assess changes in mouse behavior. Immunohistochemistry techniques were used to quantify the expression levels of amyloid-beta 42 (Aβ42) and microtubule-associated protein 1A/1B-light chain 3 (LC3) in hippocampal tissues, while western blot analysis was used to investigate the levels of LC3-II, p62, phosphoinositide 3-kinase (PI3K), and mammalian target of rapamycin (mTOR) proteins within hippocampal tissues.</p><p><strong>Results: </strong>Mice allocated to group B exhibited reduced escape latency and prolonged dwell time in the target quadrant compared to other groups. Histological examination revealed conspicuous plaque-like deposits of Aβ42 in the hippocampal tissues of mice in groups A and B. Group B displayed diminished Aβ42-positive reactants and augmented microtubule-associated protein 1A/1B-LC3-positive reactants compared to group A. LC3-positive reactants were also detected in the hippocampal tissues of mice in groups C and D, surpassing the levels observed in groups A and B. Furthermore, group B demonstrated significantly lower expression of mTOR protein and markedly higher expression of LC3-II protein in mouse hippocampal tissues when compared to group A (<i>P</i> < 0.05). Conversely, there were no significant disparities noted in PI3K and p62 protein expression between groups B and A. Notably, no discernible discrepancies were observed in the expression levels of mTOR, PI3K, LC3-II, and p62 proteins between groups C and D within mouse hippocampal tissues.</p><p><strong>Conclusion: </strong>HBO treatment demonstrates efficacy in enhancing cognitive function in mice with AD and holds promise as a potential therapeutic intervention for AD by facilitating the activation of the mTOR pathway-mediated autophagy.</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1418081"},"PeriodicalIF":4.1,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11461206/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comparative study of interhemispheric functional connectivity in patients with basal ganglia ischemic stroke.","authors":"Jian Zhang, Shijian Chen, Chengmin Yang, Huo Liang, Xuemei Quan, Yayuan Liu, Zhijian Liang","doi":"10.3389/fnagi.2024.1408685","DOIUrl":"10.3389/fnagi.2024.1408685","url":null,"abstract":"<p><strong>Background: </strong>Voxel-mirrored homotopic connectivity (VMHC) is utilized to assess the functional connectivity of neural networks by quantifying the similarity between corresponding regions in the bilateral hemispheres of the brain. The exploration of VMHC abnormalities in basal ganglia ischemic stroke (BGIS) patients across different cerebral hemispheres has been limited. This study seeks to establish a foundation for understanding the functional connectivity status of both brain hemispheres in BGIS patients through the utilization of VMHC analysis utilizing resting-state functional magnetic resonance imaging (rs-fMRI).</p><p><strong>Methods: </strong>This study examined a total of 38 patients with left basal ganglia ischemic stroke (LBGIS), 44 patients with right basal ganglia ischemic stroke (RBGIS), and 41 individuals in a healthy control (HC) group. Rs-fMRI studies were performed on these patients, and the pre-processed rs-fMRI data were analyzed using VMHC method. Subsequently, the VMHC values were compared between three groups using a one-way ANOVA and <i>post hoc</i> analysis. Correlation analysis with clinical scales was also conducted.</p><p><strong>Results: </strong>The results indicated that compared to the HC group, significant differences were detected in postcentral gyrus, extending to precentral gyrus in both BGIS groups. <i>Post hoc</i> analysis showed that in the pairwise ROI-based comparison, individuals with LBGIS and RBGIS exhibited reduced VMHC values compared to HC groups. There was no significant difference between the LBGIS and RBGIS groups. In the LBGIS group, the VMHC value showed a negative correlation with NIHSS and a positive correlation with BI.</p><p><strong>Conclusion: </strong>The analysis of VMHC in rs-fMRI revealed a pattern of brain functional remodeling in patients with unilateral BGIS, marked by reduced synchronization and coordination between hemispheres. This may contribute to the understanding of the neurological mechanisms underlying motor dysfunction in these patients.</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1408685"},"PeriodicalIF":4.1,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11461242/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An effective screening model for subjective cognitive decline in community-dwelling older adults based on gait analysis and eye tracking.","authors":"Chenxi Hao, Xiaonan Zhang, Junpin An, Wenjing Bao, Fan Yang, Jinyu Chen, Sijia Hou, Zhigang Wang, Shuning Du, Yarong Zhao, Qiuyan Wang, Guowen Min, Yang Li","doi":"10.3389/fnagi.2024.1444375","DOIUrl":"10.3389/fnagi.2024.1444375","url":null,"abstract":"<p><strong>Objective: </strong>To evaluate the effectiveness of multimodal features based on gait analysis and eye tracking for elderly people screening with subjective cognitive decline in the community.</p><p><strong>Methods: </strong>In the study, 412 cognitively normal older adults aged over 65 years were included. Among them, 230 individuals were diagnosed with non-subjective cognitive decline and 182 with subjective cognitive decline. All participants underwent assessments using three screening tools: the traditional SCD9 scale, gait analysis, and eye tracking. The gait analysis involved three tasks: the single task, the counting backwards dual task, and the naming animals dual task. Eye tracking included six paradigms: smooth pursuit, median fixation, lateral fixation, overlap saccade, gap saccade, and anti-saccade tasks. Using the XGBoost machine learning algorithm, several models were developed based on gait analysis and eye tracking to classify subjective cognitive decline.</p><p><strong>Results: </strong>A total of 161 gait and eye-tracking features were measured. 22 parameters, including 9 gait and 13 eye-tracking features, showed significant differences between the two groups (<i>p</i> < 0.05). The top three eye-tracking paradigms were anti-saccade, gap saccade, and median fixation, with AUCs of 0.911, 0.904, and 0.891, respectively. The gait analysis features had an AUC of 0.862, indicating better discriminatory efficacy compared to the SCD9 scale, which had an AUC of 0.762. The model based on single and dual task gait, anti-saccade, gap saccade, and median fixation achieved the best efficacy in SCD screening (AUC = 0.969).</p><p><strong>Conclusion: </strong>The gait analysis, eye-tracking multimodal assessment tool is an objective and accurate screening method that showed better detection of subjective cognitive decline. This finding provides another option for early identification of subjective cognitive decline in the community.</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1444375"},"PeriodicalIF":4.1,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11462412/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum: Brain and serum lipidomic profiles implicate Lands cycle acyl chain remodeling association with <i>APOE</i>ε<i>4</i> and mild cognitive impairment.","authors":"Jason Mares, Ana Paula Costa, William J Dartora, Krista M Wartchow, Artur Lazarian, David A Bennett, Tal Nuriel, Vilas Menon, Laura Beth J McIntire","doi":"10.3389/fnagi.2024.1480818","DOIUrl":"https://doi.org/10.3389/fnagi.2024.1480818","url":null,"abstract":"<p><p>[This corrects the article DOI: 10.3389/fnagi.2024.1419253.].</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1480818"},"PeriodicalIF":4.1,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11461309/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional activity, functional connectivity and complex network biomarkers of progressive hyposmia Parkinson's disease with no cognitive impairment: evidences from resting-state fMRI study.","authors":"Lei Geng, Wenfei Cao, Juan Zuo, Hongjie Yan, Jinxin Wan, Yi Sun, Nizhuan Wang","doi":"10.3389/fnagi.2024.1455020","DOIUrl":"10.3389/fnagi.2024.1455020","url":null,"abstract":"<p><strong>Background: </strong>Olfactory dysfunction stands as one of the most prevalent non-motor symptoms in the initial stage of Parkinson's disease (PD). Nevertheless, the intricate mechanisms underlying olfactory deficits in Parkinson's disease still remain elusive.</p><p><strong>Methods: </strong>This study collected rs-fMRI data from 30 PD patients [15 with severe hyposmia (PD-SH) and 15 with no/mild hyposmia (PD-N/MH)] and 15 healthy controls (HC). To investigate functional segregation, the amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo) were utilized. Functional connectivity (FC) analysis was performed to explore the functional integration across diverse brain regions. Additionally, the graph theory-based network analysis was employed to assess functional networks in PD patients. Furthermore, Pearson correlation analysis was conducted to delve deeper into the relationship between the severity of olfactory dysfunction and various functional metrics.</p><p><strong>Results: </strong>We discovered pronounced variations in ALFF, ReHo, FC, and topological brain network attributes across the three groups, with several of these disparities exhibiting a correlation with olfactory scores.</p><p><strong>Conclusion: </strong>Using fMRI, our study analyzed brain function in PD-SH, PD-N/MH, and HC groups, revealing impaired segregation and integration in PD-SH and PD-N/MH. We hypothesize that changes in temporal, frontal, occipital, and cerebellar activities, along with aberrant cerebellum-insula connectivity and node degree and betweenness disparities, may be linked to olfactory dysfunction in PD patients.</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1455020"},"PeriodicalIF":4.1,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11461260/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NLRP3 inflammasome activation and pyroptosis are dispensable for tau pathology.","authors":"Ine Paesmans, Kristof Van Kolen, Marc Vandermeeren, Pei-Yu Shih, Dirk Wuyts, Fleur Boone, Sergio Garcia Sanchez, Karolien Grauwen, Filip Van Hauwermeiren, Nina Van Opdenbosch, Mohamed Lamkanfi, Geert van Loo, Astrid Bottelbergs","doi":"10.3389/fnagi.2024.1459134","DOIUrl":"https://doi.org/10.3389/fnagi.2024.1459134","url":null,"abstract":"<p><strong>Background: </strong>Neuroinflammation is widely recognized as a key factor in the pathogenesis of Alzheimer's disease (AD), alongside ß-amyloid deposition and the formation of neurofibrillary tangles. The NLR family pyrin domain containing 3 (NLRP3) inflammasome, part of the innate immune system, has been implicated in the neuropathology of both preclinical amyloid and tau transgenic models. Activation of the NLRP3 pathway involves an initial priming step, which increases the expression of Nlrp3 and interleukin (IL)-1β, followed by the assembly of the NLRP3 inflammasome complex, comprising NLRP3, ASC, and caspase-1. This assembly leads to the proteolytic maturation of the pro-inflammatory cytokines IL-1β and IL-18. Additionally, the NLRP3 inflammasome induces Gasdermin D (GSDMD) cleavage, forming membrane pores through which IL-1β and IL-18 are secreted. Inhibition of NLRP3 has been shown to enhance plaque clearance by modulating microglial activation. Furthermore, blocking NLRP3 in tau transgenic mice has been found to reduce tau phosphorylation by affecting the activity of certain tau kinases and phosphatases.</p><p><strong>Methods: </strong>In this study, organotypic brain slice cultures from P301S transgenic mice were treated with lipopolysaccharide (LPS) plus nigericin as a positive control or exposed to tau seeds (K18) to evaluate NLRP3 inflammasome activation. The effect of tau seeding on NLRP3 activity was further examined using Meso Scale Discovery (MSD) assays to measure IL1β secretion levels in the presence and absence of NLRP3 inhibitors. The role of NLRP3 activity was investigated in full-body <i>Nlrp3</i> knockout mice crossbred with the tau transgenic P301S model. Additionally, full-body and microglia-selective <i>Gsdmd</i> knockout mice were crossbred with P301S mice, and tau pathology and neurodegeneration were evaluated at early and late stages of the disease using immunohistochemistry and biochemical assays.</p><p><strong>Results: </strong>Activation of the NLRP3 pathway was observed in the mouse organotypic slice culture (OSC) model following stimulation with LPS and nigericin or exposure to tau seeds. However, <i>Nlrp3</i> deficiency did not mitigate tauopathy or neurodegeneration in P301S mice <i>in vivo</i>, showing only a minor effect on plasma neurofilament (NF-L) levels. Consistently, <i>Gsdmd</i> deficiency did not alter tau pathology in P301S mice. Furthermore, neither full-body nor microglia-selective <i>Gsdmd</i> deletion had an impact on neuronal pathology or the release of pro-inflammatory cytokines.</p><p><strong>Conclusion: </strong>The absence of key components of the NLRP3 inflammasome pathway did not yield a beneficial effect on tau pathology or neurodegeneration in the preclinical Tau-P301S mouse model of AD. Nonetheless, organotypic slice cultures could serve as a valuable <i>ex vivo</i> mechanistic model for evaluating NLRP3 pathway activation and pharmacological inhibitors.</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1459134"},"PeriodicalIF":4.1,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11458539/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Brain activation in older adults with hypertension and normotension during standing balance task: an fNIRS study.","authors":"Weichao Fan, Qing Zeng, Peng Zheng, Shuyang Wen, Gege Li, Tao Fan, Guozhi Huang, Manxu Zheng, Qinglu Luo","doi":"10.3389/fnagi.2024.1458494","DOIUrl":"https://doi.org/10.3389/fnagi.2024.1458494","url":null,"abstract":"<p><strong>Background: </strong>Hypertension (HT) is a common chronic disease in older adults. It not only leads to dizziness and other symptoms affecting balance in older adults with HT but also affects the hemodynamics of the cerebral cortex. At present, potential neural mechanisms of balance control in older adults with HT are still unclear. Therefore, this study aimed to explore the differences in the center of pressure (COP) and cerebral cortex activation between older adults with HT and normotension (NT) during standing balance tasks. This study May provide guidance for the early detection of the risk of falls among older adults with HT and the development of clinical rehabilitation strategies.</p><p><strong>Methods: </strong>In this cross-sectional study, 30 older adults with NT (NT group) and 27 older adults with HT (HT group) were subjected to three conditions: task 1, standing with eyes open on a stable surface; task 2, standing with eyes closed on a stable surface; and task 3, standing with eyes open on the surface of the foam pad. Cortical hemodynamic reactions were measured using functional near-infrared spectroscopy, and COP parameters were measured using a force plate.</p><p><strong>Results: </strong>The mean velocity of the COP in the medial-lateral direction in the NT group was significantly higher than that in the HT group (<i>F</i> = 5.955, <i>p</i> = 0.018) during task 3. When proprioception was disturbed, the activation of the left premotor cortex and supplementary motor cortex in the HT group was significantly lower than that in the NT group (<i>F</i> = 14.381, <i>p</i> < 0.001).</p><p><strong>Conclusion: </strong>The standing balance function of older adults with HT does not appear to be worse based on COP parameters than those of older adults with NT. This study revealed that the changes in the central cortex related to standing balance appear to be more indicative of balance control deficits in older adults with HT than changes in peripheral COP parameters, suggesting the importance of the early evaluation of cortical activation in older adults with HT at risk of falls.</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1458494"},"PeriodicalIF":4.1,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11458469/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Screening for early Alzheimer's disease: enhancing diagnosis with linguistic features and biomarkers.","authors":"Chia-Ju Chou, Chih-Ting Chang, Ya-Ning Chang, Chia-Ying Lee, Yi-Fang Chuang, Yen-Ling Chiu, Wan-Lin Liang, Yu-Ming Fan, Yi-Chien Liu","doi":"10.3389/fnagi.2024.1451326","DOIUrl":"https://doi.org/10.3389/fnagi.2024.1451326","url":null,"abstract":"<p><strong>Introduction: </strong>Research has shown that speech analysis demonstrates sensitivity in detecting early Alzheimer's disease (AD), but the relation between linguistic features and cognitive tests or biomarkers remains unclear. This study aimed to investigate how linguistic features help identify cognitive impairments in patients in the early stages of AD.</p><p><strong>Method: </strong>This study analyzed connected speech from 80 participants and categorized the participants into early-AD and normal control (NC) groups. The participants underwent amyloid-<i>β</i> positron emission tomography scans, brain magnetic resonance imaging, and comprehensive neuropsychological testing. Participants' speech data from a picture description task were examined. A total of 15 linguistic features were analyzed to classify groups and predict cognitive performance.</p><p><strong>Results: </strong>We found notable linguistic differences between the early-AD and NC groups in lexical diversity, syntactic complexity, and language disfluency. Using machine learning classifiers (SVM, KNN, and RF), we achieved up to 88% accuracy in distinguishing early-AD patients from normal controls, with mean length of utterance (MLU) and long pauses ratio (LPR) serving as core linguistic indicators. Moreover, the integration of linguistic indicators with biomarkers significantly improved predictive accuracy for AD. Regression analysis also highlighted crucial linguistic features, such as MLU, LPR, Type-to-Token ratio (TTR), and passive construction ratio (PCR), which were sensitive to changes in cognitive function.</p><p><strong>Conclusion: </strong>Findings support the efficacy of linguistic analysis as a screening tool for the early detection of AD and the assessment of subtle cognitive decline. Integrating linguistic features with biomarkers significantly improved diagnostic accuracy.</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1451326"},"PeriodicalIF":4.1,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11456453/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A meta-analysis of the effects of transcranial direct current stimulation combined with cognitive training on working memory in healthy older adults.","authors":"Yanxin Lv, Shuo Wu, Michael A Nitsche, Tian Yue, Volker R Zschorlich, Fengxue Qi","doi":"10.3389/fnagi.2024.1454755","DOIUrl":"https://doi.org/10.3389/fnagi.2024.1454755","url":null,"abstract":"<p><strong>Background: </strong>Working memory (WM) loss, which can lead to a loss of independence, and declines in the quality of life of older adults, is becoming an increasingly prominent issue affecting the ageing population. Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique, is emerging as a potential alternative to pharmacological treatments that shows promise for enhancing WM capacity and May enhance the effects of cognitive training (CT) interventions.</p><p><strong>Objective: </strong>The purpose of this meta-analysis was to explore how different tDCS protocols in combination with CT enhanced WM in healthy older adults.</p><p><strong>Methods: </strong>Randomized controlled trials (RCTs) exploring the effects of tDCS combined with CT on WM in healthy older adults were retrieved from the Web of Science, PubMed, Embase, Scopus and the Cochrane Library databases. The search time period ranged from database inception to January 15, 2024. Methodological quality of the trials was assessed using the risk-of-bias criteria for RCTs from the Cochrane Collaboration Network, and RevMan 5.3 (Cochrane, London, United Kingdom) was used for the meta-analysis of the final literature outcomes.</p><p><strong>Results: </strong>Six RCTs with a total of 323 participants were ultimately included. The results of the meta-analysis show that tDCS combined with CT statistically significantly improves WM performance compared to the control sham stimulation group in healthy older adults [standard mean difference (SMD) = 0.35, 95% CI: 0.11-0.59, <i>I</i> ² = 0%, <i>Z</i> = 2.86, <i>p</i> = 0.004]. The first subgroup analysis indicated that, when the stimulus intensity was 2 mA, a statistically significant improvement in WM performance in healthy older adults was achieved (SMD = 0.39, 95% CI: 0.08-0.70, <i>I</i> ² = 6%, <i>Z</i> = 2.46, <i>p</i> = 0.01). The second subgroup analysis showed that long-term intervention (≥ 10 sessions) with tDCS combined with CT statistically significantly improved WM compared to the control group in healthy older adults (SMD = 0.72, 95% CI: 0.22-1.21, <i>I</i> ² = 0%, <i>Z</i> = 2.85, <i>p</i> = 0.004).</p><p><strong>Conclusion: </strong>tDCS combined with CT statistically significantly improves WM in healthy older adults. For the stimulus parameters, long-term interventions (≥ 10 sessions) with a stimulation intensity of 2 mA are the most effective.</p>","PeriodicalId":12450,"journal":{"name":"Frontiers in Aging Neuroscience","volume":"16 ","pages":"1454755"},"PeriodicalIF":4.1,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11456488/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142389230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}