scholarly journals Age-Related Reduced Somatosensory Gating Is Associated with Altered Alpha Frequency Desynchronization

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Chia-Hsiung Cheng ◽  
Pei-Ying S. Chan ◽  
Sylvain Baillet ◽  
Yung-Yang Lin
Keyword(s):  
Power Analysis ◽  
Spectral Power ◽  
The Elderly ◽  
Oscillatory Activity ◽  
Norm Estimates ◽  
Preattentive Processing ◽  
Secondary Somatosensory Cortex ◽  
Age Related ◽  
The Central Nervous System ◽  
Somatosensory Gating

Sensory gating (SG), referring to an attenuated neural response to the second identical stimulus, is considered as preattentive processing in the central nervous system to filter redundant sensory inputs. Insufficient somatosensory SG has been found in the aged adults, particularly in the secondary somatosensory cortex (SII). However, it remains unclear which variables leading to the age-related somatosensory SG decline. There has been evidence showing a relationship between brain oscillations and cortical evoked excitability. Thus, this study used whole-head magnetoencephalography to record responses to paired-pulse electrical stimulation to the left median nerve in healthy young and elderly participants to test whether insufficient stimulus 1- (S1-) induced event-related desynchronization (ERD) contributes to a less-suppressed stimulus 2- (S2-) evoked response. Our analysis revealed that the minimum norm estimates showed age-related reduction of SG in the bilateral SII regions. Spectral power analysis showed that the elderly demonstrated significantly reduced alpha ERD in the contralateral SII (SIIc). Moreover, it was striking to note that lower S1-induced alpha ERD was associated with higher S2-evoked amplitudes in the SIIc among the aged adults. Conclusively, our findings suggest that age-related decline of somatosensory SG is partially attributed to the altered S1-induced oscillatory activity.

Neuromuscular adaptations to healthy aging

2018 ◽  
Vol 43 (11) ◽  
pp. 1158-1165 ◽  
Author(s):  
Chris J. McNeil ◽  
Charles L. Rice
Keyword(s):  
Daily Living ◽  
Healthy Aging ◽  
The Elderly ◽  
Neuromuscular System ◽  
Healthy Humans ◽  
Age Related ◽  
Physiological Adaptations ◽  
Neuromuscular Adaptations ◽  
The Central Nervous System ◽  
Stimulation Of

Even in the absence of disease or disability, aging is associated with marked physiological adaptations within the neuromuscular system. An ability to perform activities of daily living and maintain independence with advanced age is reliant on the health of the neuromuscular system. Hence, it is critical to elucidate the age-related adaptations that occur within the central nervous system and the associated muscles to design interventions to maintain or improve neuromuscular function in the elderly. This brief review focuses on the neural alterations observed at both spinal and supraspinal levels in healthy humans in their seventh decade and beyond. The topics addressed are motor unit loss and remodelling, neural drive, and responses to transcranial magnetic stimulation of the motor cortex.

COGNITIVE AGING AND COGNITIVE RESERVE: POINT OF CONTACT

2020 ◽  
pp. 256-264
Author(s):  
В. С. Мякотных ◽  
А. П. Сиденкова ◽  
Е. С. Остапчук ◽  
И. А. Кулакова ◽  
Н. А. Белых ◽  
...  
Keyword(s):  
Cognitive Aging ◽  
Cognitive Reserve ◽  
Cognitive Disorders ◽  
The Elderly ◽  
Educational Process ◽  
Special Role ◽  
Age Related ◽  
The Central Nervous System ◽  
The One

Высокий риск когнитивных расстройств у лиц пожилого и старческого возраста заставляет, с одной стороны, искать их причины, с другой - возможности профилактики. В связи с этим в последние годы получило распространение понятие когнитивного резерва, подразумевающего совокупность количественных параметров головного мозга и его способности сохранять высокую функциональную активность в процессе старения и на фоне связанной с возрастом патологии головного мозга. Представленный в статье материал на основе обзора научной литературы освещает два основных момента, касающихся возможности сохранения когнитивного резерва, - гендерный и образовательный факторы. Указывается на разные возможности женщин и мужчин, связанные со структурными и функциональными особенностями ЦНС у представителей разного пола, и на особую роль поддерживаемого в течение всей жизни образовательного процесса. Обозначена авторская позиция о необходимости разделения понятий образования и образованности, то есть уровня общей культуры и создания удобного инструмента для определения последнего. Это, в свою очередь, помогло бы в разработке модели когнитивного резерва, нацеленной на предотвращение трансформации физиологического когнитивного старения в патологическое. The high risk of cognitive disorders in the elderly and senile age makes, on the one hand, to look for their causes, on the other - the possibility of prevention. In this regard, in recent years, the concept of cognitive reserve has become widespread, implying a set of quantitative parameters of the brain and its ability to maintain high functional activity in the process of aging and against the background of age-related brain pathology. The material presented in the article on the basis of the review of scientific literature highlights two main points concerning the possibility of preserving the cognitive reserve-gender and educational factors. It is pointed to the different opportunities of women and men associated with the structural and functional characteristics of the Central nervous system in representatives of different sexes and the special role of the educational process supported throughout life. The author’s position on the need to separate the concepts of education and the level of General culture, and the creation of a convenient tool for determining the latter is indicated. This, in turn, would help in the development of a cognitive reserve model aimed at preventing the transformation of physiological cognitive aging into pathological aging.

scholarly journals 1/fNeural Noise and Electrophysiological Indices of Contextual Prediction in Normative Aging

2017 ◽  
Author(s):  
S. Dave ◽  
T.A. Brothers ◽  
T.Y. Swaab
Keyword(s):  
Language Processing ◽  
Spectral Power ◽  
Neuronal Firing ◽  
Predictive Processing ◽  
Oscillatory Activity ◽  
Neural Activation ◽  
Discourse Comprehension ◽  
Cross Sectional ◽  
Neural Noise ◽  
Age Related

AbstractPrediction during language comprehension has increasingly been suggested to play a substantive role in efficient language processing. Emerging models have postulated that predictive mechanisms are enhanced when neural networks fire synchronously, but to date, this relationship has been investigated primarily through oscillatory activity in narrow frequency bands. A recently-developed measure proposed to reflect broadband neural activity – and thereby synchronous neuronal firing – is 1/fneural noise extracted from EEG spectral power. Previous research (Voytek et al., 2015) has indicated that this measure of 1/fneural noise changes across the lifespan, and these neural changes predict age-related behavioral impairments in visual working memory. Using a cross-sectional sample of young and older adults, we examined age-related changes in 1/fneural noise and whether this measure would predict ERP correlates of successful lexical prediction during discourse comprehension. 1/fneural noise across two different language tasks revealed high within-subject correlations, indicating that this measure can provide a reliable index of individualized patterns of neural activation. In addition to age, 1/fnoise was a significant predictor of N400 effects of successful lexical prediction, but noise did not mediate age-related declines in other ERP effects. We discuss broader implications of these findings for theories of predictive processing, as well as potential applications of 1/fnoise across research populations.

I. Age-related changes in the enteric nervous system

2002 ◽  
Vol 283 (3) ◽  
pp. G489-G495 ◽  
Author(s):  
Paul R. Wade
Keyword(s):  
Nervous System ◽  
Enteric Nervous System ◽  
The Elderly ◽  
Future Directions ◽  
Age Related ◽  
Clinical Literature ◽  
Pharmacological Studies ◽  
The Central Nervous System ◽  
Irritable Bowel ◽  
Age Related Changes

As we enter the 21st century, the segment of the population that is the most rapidly expanding is that comprised of individuals 85 yr of age and older. Dysfunctions of the gastrointestinal (GI) system, including dysphagia, constipation, diarrhea, and irritable bowel syndrome are more common complaints of the elderly, yet our knowledge of the aging GI tract is incomplete. Compared with the rapid advances in the neurobiology of aging in the central nervous system, the understanding of age-related changes in the enteric nervous system (ENS) is poor. In this brief review, I recap experiments that reveal neurodegenerative changes and their functional correlates in the ENS of mice, rats, and guinea pigs. Clinical literature seems indicative of similar structural and functional age-related changes in the human ENS. Current studies that address the mechanisms underlying age-related changes in the ENS are introduced. The future directions for this field include physiological and pharmacological studies, especially at cellular and molecular levels. Research in the aging ENS is poised to make major advances, and this new knowledge will be useful for clinicians seeking to better understand and treat GI dysfunction in the elderly.

scholarly journals Age-Related Changes in Muscle Fatigue Resistance in Humans

2000 ◽  
Vol 27 (3) ◽  
pp. 220-228 ◽  
Author(s):  
K. Ming Chan ◽  
Asim J. Raja ◽  
Fay J. Strohschein ◽  
Katherine Lechelt
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Muscle Fatigue ◽  
Fatigue Resistance ◽  
The Elderly ◽  
Voluntary Activation ◽  
Elderly Subjects ◽  
Maximal Voluntary Isometric Contraction ◽  
Age Related ◽  
The Central Nervous System

Objective:The goal of this study was to compare the relative contributions from the muscle and the central nervous system to muscle fatigue resistance in aging.Methods:Each subject carried out 90 s of sustained maximal voluntary isometric contraction (MVC) of the thumb using the thenar and forearm thumb muscles. Contractile capacity of the thenar muscles was assessed through tetanic stimulation of the median nerve. Interpolated doublets delivered during an MVC represented the overall voluntary activation level while transcranial cortical stimulation with an electromagnetic stimulator was used to assess motor output upstream from the corticomotoneuronal pathway.Results:Nine elderly subjects [four females and five males, 70±9 years old (mean±SD)] and 10 younger subjects (five females and five males, 30±6 years old) were tested. After the fatiguing exercise, the elderly group's MVC declined by 29% as opposed to 47% in the younger group (p<0.01). The elderly group's greater fatigue resistance was accounted for by increased fatigue resistance at the muscle level as well as in the central nervous system. At least some of the decline in the central motor drive was upstream from the corticomotoneuronal pathway.Conclusion:The higher muscle fatigue resistance in the elderly group was attributable to differences in both the peripheral and central nervous systems.

The Biological Clock and Sleep in the Elderly

2006 ◽  
Vol 19 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Myriam Juda ◽  
Mirjam Münch ◽  
Anna Wirz-Justice ◽  
Martha Merrow ◽  
Till Roenneberg
Keyword(s):  
Circadian Rhythms ◽  
Biological Clock ◽  
The Elderly ◽  
Early Morning ◽  
Behavioral Changes ◽  
Older Age ◽  
Age Related ◽  
Theoretical Considerations ◽  
Sleep Difficulties ◽  
Circadian Biology

Abstract: Among many other changes, older age is characterized by advanced sleep-wake cycles, changes in the amplitude of various circadian rhythms, as well as reduced entrainment to zeitgebers. These features reveal themselves through early morning awakenings, sleep difficulties at night, and a re-emergence of daytime napping. This review summarizes the observations concerning the biological clock and sleep in the elderly and discusses the documented and theoretical considerations behind these age-related behavioral changes, especially with respect to circadian biology.

What Can We Learn from Sarcopenia with Curarisation in the Context of Cancer Surgery? A Review of the Literature

2019 ◽  
Vol 25 (28) ◽  
pp. 3005-3010
Author(s):  
Georges Samouri ◽  
Alexandre Stouffs ◽  
Lionel V. Essen ◽  
Olivier Simonet ◽  
Marc De Kock ◽  
...  
Keyword(s):  
Frail Elderly ◽  
Muscle Fibers ◽  
Motor Units ◽  
The Elderly ◽  
Hepatic Function ◽  
Volume Of Distribution ◽  
Neuromuscular Blocking ◽  
Cancer Surgery ◽  
Old People ◽  
Age Related

Introduction: The monitoring of the curarisation is a unique opportunity to investigate the function of the neuromuscular junction (NMJ) during cancer surgery, especially in frailty-induced and age-related sarcopenia. Method: We conducted a comprehensive literature review in PubMed, without any limit of time related to frailty, sarcopenia, age and response to neuromuscular blockers in the context of cancer surgery. Results: Several modifications appear with age: changes in cardiac output, a decrease in muscle mass and increase in body fat, the deterioration in renal and hepatic function, the plasma clearance and the volume of distribution in elderly are smaller. These changes can be exacerbated in cancer patients. We also find modifications of the NMJ: dysfunctional mitochondria, modifications in the innervation of muscle fibers and motor units, uncoupling of the excitation-contraction of muscle fibers, inflammation. : Neuromuscular blocking agents (NMBAs) compete with acetylcholine and prevent it from fixing itself on its receptor. Many publications reported guidelines for using NMBAs in the elderly, based on studies comparing old people with young people. : No one screened frailty before, and thus, no studies compared frail elderly and non-frail elderly undergoing cancer surgery. Conclusion: Despite many studies about curarisation in the specific populations, and many arguments for a potential interest for investigation, no studies investigated specifically the response to NMBAs in regard of the frailty-induced and age-related sarcopenia.

EEG correlates of cognitive functions and neuropsychiatric disorders: A review of oscillatory activity and neural synchrony abnormalities

2020 ◽  
Vol 16 ◽  
Author(s):  
Meysam Amidfar ◽  
Yong-Ku Kim
Keyword(s):  
Psychiatric Disorders ◽  
Cognitive Functions ◽  
Spectral Power ◽  
Large Body ◽  
Oscillatory Activity ◽  
Brain Oscillations ◽  
Emotional Symptoms ◽  
Obsessive Compulsive ◽  
Neuropsychiatric Diseases ◽  
Obsessive Compulsive Disorders

Background: A large body of evidence suggested that disruption of neural rhythms and synchronization of brain oscillations are correlated with variety of cognitive and perceptual processes. Cognitive deficits are common features of psychiatric disorders that complicate treatment of the motivational, affective and emotional symptoms. Objective: Electrophysiological correlates of cognitive functions will contribute to understanding of neural circuits controlling cognition, the causes of their perturbation in psychiatric disorders and developing novel targets for treatment of cognitive impairments. Methods: This review includes description of brain oscillations in Alzheimer’s disease, bipolar disorder, attentiondeficit/hyperactivity disorder, major depression, obsessive compulsive disorders, anxiety disorders, schizophrenia and autism. Results: The review clearly shows that the reviewed neuropsychiatric diseases are associated with fundamental changes in both spectral power and coherence of EEG oscillations. Conclusion: In this article we examined nature of brain oscillations, association of brain rhythms with cognitive functions and relationship between EEG oscillations and neuropsychiatric diseases. Accordingly, EEG oscillations can most likely be used as biomarkers in psychiatric disorders.

scholarly journals A Narrative Review on Sarcopenia in Type 2 Diabetes Mellitus: Prevalence and Associated Factors

Nutrients ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 183
Author(s):  
Anna Izzo ◽  
Elena Massimino ◽  
Gabriele Riccardi ◽  
Giuseppe Della Pepa
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Elderly Population ◽  
The Elderly ◽  
Narrative Review ◽  
Macrovascular Complications ◽  
Diabetic Patients ◽  
Age Related

Type 2 diabetes mellitus (T2DM) represents a major health burden for the elderly population, affecting approximately 25% of people over the age of 65 years. This percentage is expected to increase dramatically in the next decades in relation to the increased longevity of the population observed in recent years. Beyond microvascular and macrovascular complications, sarcopenia has been described as a new diabetes complication in the elderly population. Increasing attention has been paid by researchers and clinicians to this age-related condition—characterized by loss of skeletal muscle mass together with the loss of muscle power and function—in individuals with T2DM; this is due to the heavy impact that sarcopenia may have on physical and psychosocial health of diabetic patients, thus affecting their quality of life. The aim of this narrative review is to provide an update on: (1) the risk of sarcopenia in individuals with T2DM, and (2) its association with relevant features of patients with T2DM such as age, gender, body mass index, disease duration, glycemic control, presence of microvascular or macrovascular complications, nutritional status, and glucose-lowering drugs. From a clinical point of view, it is necessary to improve the ability of physicians and dietitians to recognize early sarcopenia and its risk factors in patients with T2DM in order to make appropriate therapeutic approaches able to prevent and treat this condition.

scholarly journals An Analysis of the External Validity of EEG Spectral Power in an Uncontrolled Outdoor Environment during Default and Complex Neurocognitive States

2021 ◽  
Vol 11 (3) ◽  
pp. 330
Author(s):  
Dalton J. Edwards ◽  
Logan T. Trujillo
Keyword(s):  
External Validity ◽  
Spectral Power ◽  
Brain Activity ◽  
Outdoor Environment ◽  
Oscillatory Activity ◽  
Brain State ◽  
Beta Band ◽  
Eeg Spectral Power ◽  
Eeg Power ◽  
Human Participants

Traditionally, quantitative electroencephalography (QEEG) studies collect data within controlled laboratory environments that limit the external validity of scientific conclusions. To probe these validity limits, we used a mobile EEG system to record electrophysiological signals from human participants while they were located within a controlled laboratory environment and an uncontrolled outdoor environment exhibiting several moderate background influences. Participants performed two tasks during these recordings, one engaging brain activity related to several complex cognitive functions (number sense, attention, memory, executive function) and the other engaging two default brain states. We computed EEG spectral power over three frequency bands (theta: 4–7 Hz, alpha: 8–13 Hz, low beta: 14–20 Hz) where EEG oscillatory activity is known to correlate with the neurocognitive states engaged by these tasks. Null hypothesis significance testing yielded significant EEG power effects typical of the neurocognitive states engaged by each task, but only a beta-band power difference between the two background recording environments during the default brain state. Bayesian analysis showed that the remaining environment null effects were unlikely to reflect measurement insensitivities. This overall pattern of results supports the external validity of laboratory EEG power findings for complex and default neurocognitive states engaged within moderately uncontrolled environments.

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