Normal Age-related Changes Research Articles

Elucidating the neuropathological and molecular heterogeneity of amyloid-beta and tau in Alzheimer's disease through machine learning and transcriptomic integration.

Discerning functional brain network variations related to neuropathological aggregates in Alzheimer's disease (AD), including amyloid-beta (Abeta) and phosphorylated tau (p-tau), is crucial for understanding their link to cognitive decline and underlying molecular mechanisms. However, these variations are often confounded by normal aging-related changes, complicating interpretation. To address this challenge, we first defined Alzheimer's continuum cases (Abeta positive (A+), n = 129) and normal elderly (Abeta negative (A-), n = 160) using cerebral spinal fluid amyloid levels, and then applied a novel deep learning approach to resting-state connectivity using functional magnetic resonance imaging (fMRI) of the 289 subjects to disentangle A+-specific dimensions in brain network alterations from those shared with A- individuals. The identified A+-specific dimensions were further refined to predict individual Abeta and p-tau levels separately. We observed that resulting brain signatures, defined from A+-specific dimensions for predicting these two CSF biomarkers, were both attributed to the right superior temporal and anterior cingulate cortices and associated with attention and memory domains. When linking the brain signatures to gene expression data from a public transcriptomic atlas, we found that the brain signatures were associated with molecular pathways involving synaptic dysfunction and disruptions in pathways containing activity of excitatory neurons, astrocytes, and microglia. For A--shared dimensions, the Aβ-linked brain signature involved the left fusiform and right middle cingulate cortices, correlating with the language cognitive measurement and language-related molecular pathways. The p-tau-linked signature predominantly involved the right insula and inferior temporal cortices, correlating with the aging-related molecular pathways. Collectively, our findings provided new insights in understanding of Alzheimer's continuum pathological biomarkers.

Game-based Training of Cognitive Functions: An Exploratory Study Involving Seniors in Switzerland

The aging population is resulting in a worldwide rising prevalence of individuals experiencing cognitive decline, whether it be normal age-related changes or pathological conditions. Game-based training in the form of serious games represents an alternative way to enhance cognitive functions among older people. We developed a set of games to train multiple cognitive functions of seniors, considering that their level of digital literacy can vary greatly. A participatory approach has been applied to the development process, involving a multidisciplinary research team and older people. Interviews, usability tests, and a workshop were run with ten seniors (70+) in Southern Switzerland to explore accessibility, usability, and preferences. This paper presents the development process and the games created. Six different games were designed to stimulate multiple cognitive functionalities (e.g., cognitive flexibility, attentiveness, and memory). The serious games run on a tablet. Following Laamarti’s classification, we developed the games to be applied in well-being and health areas, requiring mainly mental activities through visual modalities, played through a touchscreen in a 2D digital environment. Participants appreciated the experience and the challenges provided by the games, understanding the broader aim (cognitive functions training) and the rules, and could complete the required tasks. Feedback was provided on graphical elements (icons and colours), as well as with suggestions for improvements. The tablet appeared to be functional and relatively easy to use, even for first timers. The promising results of this participatory study pave the way for the follow-up phase of the project, which will gather data on the usage of the application and its effectiveness with a greater number of subjects.

Dosing and Specificity of Training to Sustain Maximal Walking Speed in Highly Mobile Older Adults

Compared to their sedentary peers, older track athletes demonstrate a superior ability to negate the normal age-related changes in gait mechanics known to attenuate maximal walking speed performance with age. Sports-specific exercises commonly utilized to affect this end may be appropriately scaled to benefit a wider subset of older adults. Optimal dosing of resistance training to maximize gluteus maximus functional fitness, accompanied by gait reeducation to augment motor patterns facilitating optimal peak trailing leg extension and push-off intensity, create a redundancy in walking capacity likely to prolong functional independence for beneficiaries of this targeted intervention.

Effect of Neurological Music Therapy Among Older Adults with Mild Cognitive Impairment

Background: Mild cognitive impairment (MCI) is characterized by cognitive decline that exceeds normal age-related changes but does not significantly impair daily life. This condition is a precursor to dementia, including Alzheimer's disease, and affects emotional well-being and quality of life.Objective: This study aimed to evaluate the effects of neurological music therapy (MMT) on cognitive function, emotional well-being, and quality of life in older adults with MCI.Methods: A single-blinded randomized controlled trial was conducted over six weeks with 20 participants aged 60-80 years. Participants were randomly assigned to the MMT group, which received exercise therapy with music and the Naruko clapper, or the STT group, which received standard exercise guided by counts. The MoCA and SF-36 were used to assess outcomes. Data were analyzed using SPSS version 27, employing paired and independent t-tests with a significance level of p < 0.05.Results: Post-intervention, the MMT group showed a significant improvement in MoCA scores (23.33 ± 2.06) compared to the STT group (18.75 ± 2.61, p < 0.001). SF-36 scores also significantly increased in the MMT group (82.62 ± 6.16) versus the STT group (47.32 ± 11.01, p < 0.001).Conclusion: Neurological music therapy significantly enhanced cognitive and physical health outcomes in older adults with MCI, suggesting its potential as an effective non-pharmacological intervention.

The metabolic cost of breathing for exercise ventilations: effects of age and sex.

Given that there are both sex-based structural differences in the respiratory system and age-associated declines in pulmonary function, the purpose of this study was to assess the effects of age and sex on the metabolic cost of breathing (V̇o2RM) for exercise ventilations in healthy younger and older males and females. Forty healthy participants (10 young males 24 ± 3 yr; 10 young females 24 ± 3 yr; 10 older males 63 ± 3 yr, 10 older females 63 ± 6 yr) mimicked their exercise breathing patterns (voluntary hyperpnea) in the absence of exercise across a range of exercise intensities. At peak exercise, V̇o2RM represented a significantly greater fraction of peak oxygen consumption (V̇o2peak) in young females, 12.7 ± 4.0%, compared with young males, 10.7 ± 3.0% (P = 0.027), whereas V̇o2RM represented 13.5 ± 2.3% of V̇o2peak in older females and 13.2 ± 3.3% in older males. At relative ventilations, there was a main effect of age, with older males consuming a significantly greater fraction of V̇o2RM (6.6 ± 1.9%) than the younger males (4.4 ± 1.3%; P = 0.012), and older females consuming a significantly greater fraction of V̇o2RM (6.9 ± 2.5%) than the younger females (5.1 ± 1.4%; P = 0.004) at 65% V̇emax. Furthermore, both younger and older males had significantly better respiratory muscle efficiency than their female counterparts at peak exercise (P = 0.011; P = 0.015). Similarly, younger participants were significantly more efficient than older participants (6.5 ± 1.5% vs. 5.5 ± 2.0%; P = 0.001). Normal age-related changes in respiratory function, in addition to sex-based differences in airway anatomy, appear to influence the ventilatory responses and the cost incurred to breathe during exercise.NEW & NOTEWORTHY Here we show that at moderate and high-intensity exercise, older individuals incur a higher cost to breathe than their younger counterparts. However, as individuals age, the sex difference in the cost of breathing narrows. Collectively, our findings suggest that the normative age-related changes in respiratory structure and function, and sex differences in airway anatomy, appear to influence the ventilatory responses to exercise and the oxygen cost to breathe.

TRP Channels in Excitotoxicity.

Glutamate excitotoxicity is a central mechanism contributing to cellular dysfunction and death in various neurological disorders and diseases, such as stroke, traumatic brain injury, epilepsy, schizophrenia, addiction, mood disorders, Huntington's disease, Alzheimer's disease, Parkinson's disease, multiple sclerosis, pathologic pain, and even normal aging-related changes. This detrimental effect emerges from glutamate binding to glutamate receptors, including α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, N-methyl-d-aspartate receptors, kainate receptors, and GluD receptors. Thus, excitotoxicity could be prevented by targeting glutamate receptors and their downstream signaling pathways. However, almost all the glutamate receptor antagonists failed to attenuate excitotoxicity in human patients, mainly due to the limited understanding of the underlying mechanisms regulating excitotoxicity. Transient receptor potential (TRP) channels serve as ancient cellular sensors capable of detecting and responding to both external and internal stimuli. The study of human TRP channels has flourished in recent decades since the initial discovery of mammalian TRP in 1995. These channels have been found to play pivotal roles in numerous pathologic conditions, including excitotoxicity. In this review, our focus centers on exploring the intricate interactions between TRP channels and glutamate receptors in excitotoxicity.

Age-related changes in human brain functional connectivity using graph theory and machine learning techniques in resting-state fMRI data.

Aging is the basis of neurodegeneration and dementia that affects each endemic in the body.Normal aging in the brain is associated with progressive slowdown and disruptions in various abilities such as motor ability, cognitive impairment, decreasing information processing speed, attention, and memory. With the aggravation of global aging, more research focuses on brain changes in the elderly adult. The graph theory, in combination with functional magnetic resonance imaging (fMRI), makes it possible to evaluate the brain network functional connectivity patterns in different conditions with brain modeling. We have evaluated the brain network communication model changes in three different age groups (including 8 to 15years, 25 to 35years, and 45 to 75years) in lifespan pilot data from the human connectome project (HCP). Initially, Pearson correlation-based connectivity networks were calculated and thresholded. Then, network characteristics were compared between the three age groups by calculating the global and local graph measures. In the resting state brain network, we observed decreasing global efficiency and increasing transitivity with age. Also, brain regions, including the amygdala, putamen, hippocampus, precuneus, inferior temporal gyrus, anterior cingulate gyrus, and middle temporal gyrus, were selected as the most affected brain areas with age through statistical tests and machine learning methods. Using feature selection methods, including Fisher score and Kruskal-Wallis, we were able to classify three age groups using SVM, KNN, and decision-tree classifier. The best classification accuracy is in the combination of Fisher score and decision tree classifier obtained, which was 82.2%. Thus, by examining the measures of functional connectivity using graph theory, we will be able to explore normal age-related changes in the human brain, which can be used as a tool to monitor health with age.

18 Vascular Risk, Cerebral White Matter, and Executive Functioning in Vietnam-Era Veterans with Traumatic Brain Injury and/or Post-Traumatic Stress Disorder: A Department of Defense Alzheimer’s Disease Initiative (DoD-ADNI) Study

Objective:Research indicates that Veterans with a history of traumatic brain injury (TBI) are at increased risk for dementia. Although the precise mechanisms underlying this relationship are poorly understood, remote TBI may exacerbate normal age-related changes to cerebral white matter (WM) and result in cognitive decline. However, Veterans commonly experience a constellation of mental (e.g., post-traumatic stress disorder [PTSD] and depression) and vascular (e.g., diabetes, hypertension, obesity) health conditions that have also been implicated in pathologic cerebral WM and cognitive aging trajectories. Therefore, the present study sought to (1) clarify the effects of remote TBI within the context of PTSD, depression, and vascular risk on WM micro- and macrostructure, and (2) explore if WM integrity is associated with cognition in a sample of Vietnam-Era Veterans.Participants and Methods:The sample consisted of 195 male Veterans ages 60-80 (mean age=69.3) enrolled in the Department of Defense-Alzheimer’s Disease Neuroimaging Initiative (DoD-ADNI) study. 102 Veterans met criteria for TBI by sustaining a head-injury that resulted in a loss of consciousness, alteration of consciousness, or post-traumatic amnesia. Current and/or lifetime PTSD was designated by scores >30 on the Clinician-Administered PTSD Scale. The Geriatric Depression Scale was used as a continuous measure of depression. A vascular risk score (0-3) was calculated based on diabetes, hypertension, and obesity (BMI >30 kg/m2). An executive functioning composite was created by averaging sample-specific z-scores for Trail Making Tests (A and B), with higher scores indicating worse performance. Voxelwise analysis of WM microstructure (fractional anisotropy [FA]) was conducted with Tract-Based Spatial Statistics (TBSS), using non-parametric permutation testing with threshold-free cluster enhancement. SPM’s Lesion Segmentation Tool was used to investigate WM macrostructure (WM hyperintensity [WMH] volume). Lesion probability maps were masked to restrict WMH volume calculations to WM. Robust regression using M-estimation and predictive R2 calculated using 10-fold cross-validation examined WMH volume, predictor, and cognitive associations. Age was a covariate in all WM analyses, and education was a covariate in all cognitive analyses.Results:TBSS analysis revealed widespread, significant negative relationships between vascular risk and FA across numerous WM tracts (p’s<0.05). These associations remained significant after adjusting for TBI history, PTSD, and depression. TBSS identified significant positive relationships between executive functioning performance and FA across similar brain regions (p’s<0.05). Robust regressions revealed that vascular risk significantly predicted WMH volume (p=0.006; ß=0.161; R2=0.093), whereas TBI history, PTSD, and depression did not (p’s=0.107-0.166; ß's=-0.089-0.101). WMH volume significantly predicted executive functioning (p=0.002; ß=0.216; R2=0.105), whereas TBI history, PTSD, depression, and vascular risk did not (p’s=0.123-0.888; ß's=-0.012-0.125).Conclusions:Our results suggest that vascular health, relative to remote TBI, PTSD, and depression, may be more robustly associated with cerebral WM micro- and macrostructure in older Veterans. Furthermore, poorer WM integrity is associated with poorer cognitive performance. These findings underscore the importance of vascular health interventions in preventing negative brain and cognitive aging outcomes in Veterans, independent of TBI history. Future studies might leverage other neuroimaging modalities (e.g., functional MRI) to further investigate the effects of vascular health on aging in Veterans with a history of TBI.

Does serum neurofilament light help predict accelerated cognitive ageing in unimpaired older adults?

Neurofilament light (NfL) is a blood biomarker of neurodegeneration. While serum NfL levels have been demonstrated to increase with normal ageing, the relationship between serum NfL levels and normal age-related changes in cognitive functions is less well understood. The current study investigated whether cross-sectional serum NfL levels measured by single molecule array technology (Simoa®) mediated the effect of age on cognition, measured by a battery of neuropsychological tests administered biannually for 8 years, in a cohort of 174 unimpaired older adults (≥50 years) from the Tasmanian Healthy Brain Project. Mediation analysis was conducted using latent variables representing cognitive test performance on three cognitive domains - episodic memory, executive function, and language (vocabulary, comprehension, naming). Cognitive test scores for the three domains were estimated for each participant, coincident with blood collection in 2018 using linear Bayesian hierarchical models. Higher serum NfL levels were significantly positively associated with age (p < 0.001 for all domains). Cognitive test scores were significantly negatively associated with age across the domains of executive function (p < 0.001), episodic memory (p < 0.001) and language (p < 0.05). However, serum NfL levels did not significantly mediate the relationship between age and cognitive test scores across any of the domains. This study adds to the literature on the relationship between serum NfL levels and cognition in unimpaired older adults and suggests that serum NfL is not a pre-clinical biomarker of ensuing cognitive decline in unimpaired older adults.

Sclerochoroidal Calcification Leads to Diagnosis of Primary Parathyroid Cancer

Introduction There are many innocuous retinal findings which arise from normal age-related change. It is important to distinguish sclerochoroidal calcifications (SCC) as either benign or malignant. Sclerochoroidal calcifications are pale, elevated fundus lesions found in the sclera, choroid, and/ or retina that originate from excess calcium deposition onto normal tissue. This uncommon finding is often benign, and the patient suffers no visual or systemic complications. However, in rare circumstances, these retinal lesions can originate from potentially harmful systemic conditions. A careful ophthalmic and systemic work up is needed to determine the lesion’s etiology and if intervention is required. This case demonstrates a causal relationship between a SCC fundus lesion and primary parathyroid cancer. CE Notification This article is available as a COPE accredited CE course. You may take this course for 1-hour credit. Read the article and take the qualifying test to earn your credit. Please check COPE course expiry date prior to enrollment. The COPE course test must be taken before the course expiry date.

AB102. SOH23ABS_250. A profile of patients with shoulder pain attending the musculoskeletal triage clinic in Connolly Hospital

Background: Clinical specialist physiotherapists (CSP) have been assessing patients in musculoskeletal (MSK) triage clinics nationally since 2010. There is a close correlation between physiotherapists and surgeons in making the correct diagnosis. Physiotherapy involving a structured exercise program is the first line treatment for patients with rotator cuff related shoulder pain (RCRSP) and is recommended prior to orthopaedic consultant referral. The benefit of an early magnetic resonance imaging (MRI) in these patients is questionable and may cause patients undue concern about normal age-related changes in their shoulder.

Cellular senescence and the blood-brain barrier: Implications for aging and age-related diseases.

The blood-brain barrier (BBB) is a critical physiochemical interface that regulates communication between the brain and blood. It is comprised of brain endothelial cells which regulate the BBB's barrier and interface properties and is surrounded by supportive brain cell types including pericytes and astrocytes. Recent reports have suggested that the BBB undergoes dysfunction during normative aging and in disease. In this review, we consider the effect of cellular senescence, one of the nine hallmarks of aging, on the BBB. We first characterize known normative age-related changes at the BBB, and then evaluate changes in neurodegenerative diseases, with an emphasis on if/how cellular senescence is influencing these changes. We then discuss what insight has been gained from in vitro and in vivo studies of cellular senescence at the BBB. Finally, we evaluate mechanisms by which cellular senescence in peripheral pathologies can indirectly or directly affect BBB function.

Drusen-aware model for age-related macular degeneration recognition.

The purpose of this study was to build an automated age-related macular degeneration (AMD) colour fundus photography (CFP) recognition method that incorporates confounders (other ocular diseases) and normal age-related changes by using drusen masks for spatial feature supervision. A range of clinical sources were used to acquire 7588 CFPs. Contrast limited adaptive histogram equalisation was used for pre-processing. ResNet50 was used as the backbone network, and a spatial attention block was added to integrate prior knowledge of drusen features into the backbone. The evaluation metrics used were sensitivity, specificity and F1 score, which is the harmonic mean of precision and recall (sensitivity) and area under the receiver-operating characteristic (AUC). Fivefold cross-validation was performed, and the results compared with four other methods. Excellent discrimination results were obtained with the algorithm. On the public dataset (n=6565), the proposed method achieved a mean (SD) sensitivity of 0.54 (0.09), specificity of 0.99 (0.00), F1 score of 0.62 (0.06) and AUC of 0.92 (0.02). On the private dataset (n=1023), the proposed method achieved a sensitivity of 0.92 (0.02), specificity of 0.98 (0.01), F1 score of 0.92 (0.01) and AUC of 0.98 (0.01). The proposed drusen-aware model outperformed baseline and other vessel feature-based methods in F1 and AUC on the AMD/normal CFP classification task and achieved comparable results on datasets that included other diseases that often confound classification. The method also improved results when a five-category grading protocol was used, thereby reflecting discriminative ability of the algorithm within a real-life clinical setting.

Age-related changes for the predictors of benign prostatic hyperplasia in Chinese men aged 40 years or older.

A cross-sectional study was conducted to estimate the age-stratified normal levels and age-related changes in the risk predictors of benign prostatic hyperplasia (BPH) progression. A total of 4706 male participants aged 40 years or older in Zhengzhou (China) were enrolled. The values of the International Prostate Symptom Score (IPSS), prostate-specific antigen (PSA), prostate volume (PV), and postvoid residual urine volume (PVR) significantly increased with age. Nonlinear relationships between age and IPSS scores ≥8 (P for nonlinearity = 0.046), PSA level ≥1.6 ng ml-1, PV ≥31 ml, or PVR ≥39 ml (all P for nonlinearity <0.001) were observed. After the age of 61 years, the risk indicators related to BPH progression were positively correlated with age (odds ratio [OR] >1), regardless of the predictors of the IPSS score, PSA level, PV, or PVR; and the OR values increased gradually. Therefore, after the age of 61 years, the risk predictors related to BPH progression were positively correlated with age.

Validity and reliability of the Farsi version of the ascertain dementia 8-item (AD8-F) informant interview in Iranian patients with mild neurocognitive disorder

BackgroundFor screening and distinguishing between mild neurocognitive disorder (mNCD) and normal cognitive age-related changes in primary care centers, a simple and practical tool is necessary. Therefore, this study aims to determine the validity and reliability of the Farsi version of the Ascertain Dementia 8-item (AD8-F) informant interview in patients with mNCD.MethodsThis is a study of the psychometric properties of the Farsi AD8. The participants include sixty informant-patient dyads with mNCD and sixty controls with normal cognition. The AD8 was compared to the mini-mental state examination (MMSE) and the Mini-Cog. As a gold standard, the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for mNCD was used. The reliability was measured using internal consistency and test-retest. Validity was assessed by evaluating the content, concurrent, and construct validity. Data were analyzed via Cronbach’s α, Pearson correlation, independent t-test, and analysis of variance (ANOVA) and area under the curve (AUC) by statistical package for the social sciences (SPSS) v.23.ResultsCronbach’s α was 0.71. Test-retest reproducibility was 0.8. The AD8 had inverse correlations with the Mini-Cog (r = − 0.70, P < 0.01) and MMSE (r = − 0.56, P < 0.01). The area under the curve was 0.88. The optimal cutoff score was > 2. Sensitivity and specificity were 80 and 83%, respectively. The positive predictive value was 83%. The negative predictive value was 81%.ConclusionOur results suggest that this tool can be used as a screening tool to detect a mild neurocognitive disorder in primary care centers.

Shape of cerebral hemispheres: structural and spatial complexity. Quantitative analysis of skeletonized MR images

For quantitative characterization of the complexity of the spatial configuration of anatomical structures, including cerebral hemispheres, fractal analysis is the most often used method, in addition to which, other methods of image analysis are quite promising, including quantitative analysis of skeletonized images. The purpose of the study was to determine the features of the structural and spatial complexity of the cerebral hemispheres shape using quantitative analysis of skeletonized magnetic resonance images of the cerebral hemispheres. Magnetic resonance brain images of 100 conditionally healthy individuals (who did not have structural changes in the brain) of both sexes (56 women, 44 men) aged 18-86 years (average age 41.72±1.58 years) were studied, 5 tomographic sections (4 coronal sections and 1 axial section) were selected from the set of tomographic images of each brain. During preprocessing, image segmentation was performed to obtain a binary silhouette image, after which silhouette skeletonizing was carried out. Quantitative analysis of skeletonized images included determination of the following parameters: branches, junctions, end-point voxels, junction voxels, slab voxels, triple points, quadruple points, average branch length, maximum branch length. We divided quantitative parameters of skeletonized images into two groups. The first group included branches, junctions, end-point voxels, junction voxels, slab voxels, triple points, quadruple points. These parameters were related to each other and to the values of the fractal dimension by positive correlations. The second group of parameters included average branch length, maximum branch length. These parameters were positively correlated, but they had negative correlations with most of the parameters of the first group and with fractal dimension values. Quantitative parameters and fractal dimension turned out to be better parameters for characterizing the spatial and structural complexity of the cerebral hemispheres shape than traditional morphometric parameters (area, perimeter and their derivatives). It was found that the values of most of the investigated quantitative parameters decreased with age; coronal sections were the most representative for characterizing age-related changes. Quantitative assessment of the brain shape, including spatial and structural complexity, can become an informative tool for the diagnosis of some nervous diseases and the differentiation of pathological and normal age-related changes.

Dysregulation of ACE-1 in Normal Aging and the Early Stages of Alzheimer's Disease.

An imbalance in the renin-angiotensin system (RAS) is associated with cognitive decline and disease pathology in Alzheimer's disease (AD). In this study, we have investigated changes in the brain angiotensin-converting enzyme-1 (ACE-1) and angiotensin-II (Ang-II), and the counter-regulatory angiotensin-converting enzyme-2 (ACE-2), in the frontal and temporal cortex during normal aging and in the early stages of AD. We studied a cohort of normal aging (n = 121; 19-95 years age-at-death) from the Sudden Death Brain Bank, University of Edinburgh, United Kingdom, and AD and age-matched controls (n = 60) from the South West Dementia Brain Bank, University of Bristol, United Kingdom, stratified according to Braak tangle stage (BS): 0-II, III-IV (intermediate disease), and V-VI (end-stage disease). ACE-1 and ACE-2 enzyme activity were measured using fluorogenic peptide activity assays. ACE-1, ACE-2, and Ang-II protein level were measured by enzyme-linked immunosorbent assay (ELISA). In both regions, ACE-1 protein and Ang-II levels correlated positively with age whereas ACE-1 enzyme activity was inversely related to age. ACE-1 protein correlated positively with Ang-II, whilst ACE-1 activity correlated inversely with Ang-II in normal aging. ACE-1 enzyme activity was elevated at an early/intermediate stage, BS III-IV compared to BS 0-II in the temporal cortex in AD. ACE-2 protein and enzyme activity were unchanged with aging and in AD. In conclusion, ACE-1 activity is induced in the early stages of AD independently from normal physiological age-related changes in ACE-1 protein.

The Role of the P1 Latency in Auditory and Speech Performance Evaluation in Cochlear Implanted Children.

Auditory deprivation affects normal age-related changes in the central auditory maturation. Cochlear implants (CIs) have already become the best treatment strategy for severe to profound hearing impairment. However, it is still hard to evaluate the speech-language outcomes of the pediatric CI recipients because of hearing-impaired children with limited speech-language abilities. The cortical auditory evoked potential (CAEP) provides a window into the development of the auditory cortical pathways. This preliminary study is aimed at assessing electrophysical characteristics of P1-N1 of electrically CAEP in children with CIs and at exploring whether these changes could be accounted for in auditory and speech outcomes of these patients. CAEP responses were recorded in 48 children with CIs in response to electrical stimulus to determine the presence of the P1-N1 response. Speech perception and speech intelligibility of the implanted children were further evaluated with the categories of auditory performance (CAP) test and speech intelligibility rating (SIR) test, respectively, to explore the relationship between the latency of P1-N1 and auditory and speech performance. This study found that P1 and N1 of the intracochlear CAEP were reliably evoked in children fitted with CIs and that the latency of the P1 as opposed to that of N1 was negative in relation to the wearing time of the cochlear implant. Moreover, the latency of the P1 produced significantly negative scores in both CAP and SIR tests, which indicates that P1 latency may be reflective of the auditory performance and speech intelligibility of pediatric CI recipients. These results suggest that the latency of P1 could be used for the objective assessment of auditory and speech function evaluation in cochlear-implanted children, which would be helpful in clinical decision-making regarding intervention for young hearing-impaired children.

Age-related and sexual features of the mobility of the temporomandibular joints

Introduction.Pathology of the temporomandibular joints (TMJ) is widespread even among young people, and the frequency of its occurrence increases with the age of patients. In this case, there is violated one of the main characteristics of the joints — mobility, which is measured by the mouth opening width (MOW). There is not enough information in the literature on the age and sex characteristics of the TMJ mobility in individuals without pathology of this joint.The aimof the study is to research the mobility of the TMJ in different age groups in men and women without pathology of this joint.Materials and methods.There were examined 714 patients who applied for dental care, aged 20 to 79 years (504 women and 210 men), without pathology of the TMJ. The range of motion in the TMJ was measured using a caliper with thin lips during the opening of the mouth in a neutral head position. The subjects were divided into age groups: 20–29, 30–39, 40–49, 50–59, 60–69 and 70–79 years old.Results.It was found that the most common MOW value was 4,9 cm (range from 4,5 to 5,2 cm). A distribution of relative frequencies corresponding to the normal Gaussian distribution was observed for this indicator. The mobility of the TMJ changed little with age. Analysis of the distribution of temporomandibular joint mobility by age groups of patients with a step of 10 years showed the similarity of the average MOW values in all groups of subjects, except for the group of 20–29 years. Their average values (4,75 cm) were lower than those of the other groups (4,9 cm,p&lt;0,05). It was found that men have a higher mobility of the TMJ compared to women in all age groups (on average by 0,28 cm,p&lt;0,05).Conclusion.Mouth opening widths of 4,6 to 5,2 cm (average 4,9 cm) can be considered as normal. TMJ mobility is not related to age. Consequently, a decrease in the mobility of the TMJ in persons of older age groups cannot be considered as normal age-related changes. TMJ mobility depends on sex. Men have higher TMJ mobility than women in all age groups. Thus, the TMJ differ from other joints not only in their complexity (two joints always work together), but also in age and sex patterns of mobility.

Age-Related Alterations in EEG Network Connectivity in Healthy Aging.

Emerging studies have reported that functional brain networks change with increasing age. Graph theory is applied to understand the age-related differences in brain behavior and function, and functional connectivity between the regions is examined using electroencephalography (EEG). The effect of normal aging on functional networks and inter-regional synchronization during the working memory (WM) state is not well known. In this study, we applied graph theory to investigate the effect of aging on network topology in a resting state and during performing a visual WM task to classify aging EEG signals. We recorded EEGs from 20 healthy middle-aged and 20 healthy elderly subjects with their eyes open, eyes closed, and during a visual WM task. EEG signals were used to construct the functional network; nodes are represented by EEG electrodes; and edges denote the functional connectivity. Graph theory matrices including global efficiency, local efficiency, clustering coefficient, characteristic path length, node strength, node betweenness centrality, and assortativity were calculated to analyze the networks. We applied the three classifiers of K-nearest neighbor (KNN), a support vector machine (SVM), and random forest (RF) to classify both groups. The analyses showed the significantly reduced network topology features in the elderly group. Local efficiency, global efficiency, and clustering coefficient were significantly lower in the elderly group with the eyes-open, eyes-closed, and visual WM task states. KNN achieved its highest accuracy of 98.89% during the visual WM task and depicted better classification performance than other classifiers. Our analysis of functional network connectivity and topological characteristics can be used as an appropriate technique to explore normal age-related changes in the human brain.