scholarly journals Transcranial magnetic stimulation reveals diminished homoeostatic metaplasticity in cognitively impaired adults

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Mark H Sundman ◽  
Koeun Lim ◽  
Viet Ton That ◽  
Jack-Morgan Mizell ◽  
Chidi Ugonna ◽  
...  
Keyword(s):  
Older Adults ◽  
Cognitive Impairment ◽  
Transcranial Magnetic Stimulation ◽  
Brain Stimulation ◽  
Magnetic Stimulation ◽  
Cognitive Status ◽  
Synaptic Activity ◽  
Cognitively Impaired ◽  
Non Invasive ◽  
Potential Value

Abstract Homoeostatic metaplasticity is a neuroprotective physiological feature that counterbalances Hebbian forms of plasticity to prevent network destabilization and hyperexcitability. Recent animal models highlight dysfunctional homoeostatic metaplasticity in the pathogenesis of Alzheimer’s disease. However, the association between homoeostatic metaplasticity and cognitive status has not been systematically characterized in either demented or non-demented human populations, and the potential value of homoeostatic metaplasticity as an early biomarker of cognitive impairment has not been explored in humans. Here, we report that, through pre-conditioning the synaptic activity prior to non-invasive brain stimulation, the association between homoeostatic metaplasticity and cognitive status could be established in a population of non-demented human subjects (older adults across cognitive spectrums; all within the non-demented range). All participants (n = 40; age range, 65–74, 47.5% female) underwent a standardized neuropsychological battery, magnetic resonance imaging and a transcranial magnetic stimulation protocol. Specifically, we sampled motor-evoked potentials with an input/output curve immediately before and after repetitive transcranial magnetic stimulation to assess neural plasticity with two experimental paradigms: one with voluntary muscle contraction (i.e. modulated synaptic activity history) to deliberately introduce homoeostatic interference, and one without to serve as a control condition. From comparing neuroplastic responses across these experimental paradigms and across cohorts grouped by cognitive status, we found that (i) homoeostatic metaplasticity is diminished in our cohort of cognitively impaired older adults and (ii) this neuroprotective feature remains intact in cognitively normal participants. This novel finding suggests that (i) future studies should expand their scope beyond just Hebbian forms of plasticity that are traditionally assessed when using non-invasive brain stimulation to investigate cognitive ageing and (ii) the potential value of homoeostatic metaplasticity in serving as a biomarker for cognitive impairment should be further explored.

scholarly journals Non-invasive brain stimulation therapies

2019 ◽  
Vol 98 (4) ◽  
pp. 279-289
Author(s):  
Paulo J. C. Suen ◽  
Andre R. Brunoni
Keyword(s):  
Brain Stimulation ◽  
Magnetic Stimulation ◽  
Synaptic Activity ◽  
Noninvasive Brain Stimulation ◽  
Major Depressive ◽  
Brain Functioning ◽  
Brain Functions ◽  
Non Invasive ◽  
Activation Level ◽  
Stimulation Of

Noninvasive brain stimulation therapies are a promising field for the development of new protocols for the treatment of neuropsychiatric disorders. They are based on the stimulation of neural networks with the intent of modeling their synaptic activity to adequate levels. For this, it is necessary to precisely determine which networks are related to which brain functions, and the normal activation level of each of these networks, so that it is possible to direct the stimulation to the affected networks in order to induce the desired effects. These relationships are under intense investigation by the scientific community, and will contribute to the advancement of treatments by neurostimulation, with the emergence of increasingly accurate and effective protocols for different disorders. Currently, the most used techniques are Transcranial Direct Current Stimulation and Transcranial Magnetic Stimulation, with the most common applications being for treating Major Depressive Disorder. The advancement of research in this field may determine new target networks for stimulation in the treatment of other disorders, extending the application of these techniques and also our knowledge about brain functioning.

scholarly journals The Sequence of Physical and Cognitive Impairment and the Association with Mortality Among Unimpaired Older Mexican Adults

2019 ◽  
Vol 75 (7) ◽  
pp. 1386-1392
Author(s):  
Brian Downer ◽  
Sadaf Milani ◽  
Rebeca Wong
Keyword(s):  
Older Adults ◽  
Cognitive Impairment ◽  
Mortality Risk ◽  
Multinomial Logistic Regression ◽  
Cognitive Status ◽  
Cognitively Impaired ◽  
Proportional Hazard ◽  
Physical Impairments ◽  
Aging Study ◽  
Mexican Adults

Abstract Background Many older adults become physically and cognitively impaired. However, it is unclear whether unimpaired older adults are more likely to become physically or cognitively impaired first and if this sequence impacts mortality risk. Methods Data came from the Mexican Health and Aging Study. The sample included 1,283 participants aged ≥60 years who were physically and cognitively unimpaired in 2001. Multinomial logistic regression was used to estimate probabilities of being unimpaired, cognitively impaired only, physically impaired only, or cognitively-physically impaired in 2003. Proportional hazard models were used to estimate mortality risk through 2015 according to physical and cognitive status in 2003. Results The probabilities for being unimpaired, physically impaired only, cognitively impaired only, and cognitively-physically impaired in 2003 were 0.45, 0.22, 0.19, and 0.13, respectively. Older age, female sex, and arthritis were associated with significantly greater probability of becoming physically impaired only than cognitively impaired only in 2003. Cognitive impairment only (hazard ratio [HR] = 1.42, 95% confidence interval [CI] = 1.09–1.85) in 2003 but not physical impairment only (HR = 1.22, 95% CI = 0.94–1.58) was associated with greater mortality than being unimpaired in 2003. Cognitively-physically impaired participants had higher mortality risk than participants who were physically (HR = 1.58, 95% CI = 1.18–2.12) or cognitively (HR = 1.36, 95% CI = 1.01–1.84) impaired only. Discussion The likelihood of becoming only physically or cognitively impaired over 2 years varies by demographic and health characteristics. The mortality risk for unimpaired older adults who become cognitively impaired only is similar to those who become physically impaired only. Research should determine if the sequence of cognitive and physical impairments is associated with other outcomes.

SAFETY AND TOLERABILITY OF DIFFERENT PROTOCOLS OF HIGH-FREQUENCY RHYTHMIC TRANSCRANIAL MAGNETIC STIMULATION

2019 ◽  
pp. 26-37
Author(s):  
I.S. Bakulin ◽  
A.G. Poydasheva ◽  
D.Yu. Lagoda ◽  
K.M. Evdokimov ◽  
A.Kh. Zabirova ◽  
...  
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Side Effects ◽  
Healthy Volunteers ◽  
Brain Stimulation ◽  
High Frequency ◽  
Magnetic Stimulation ◽  
Facial Muscle ◽  
Non Invasive ◽  
Mood Changes ◽  
Invasive Method

Rhythmic transcranial magnetic stimulation (rTMS) is a non-invasive method for brain stimulation, widely used in the treatment of various diseases and in research. In this regard, the problems of rTMS safety and tolerability are becoming especially relevant. Most studies describe only serious side effects of rTMS, which, in fact, are extremely rare. Other side effects which affect rTMS tolerability have been studied to a much lesser extent. The objective of the study is to examine all side effects which occur during and after rTMS sessions through prospective open observation of patients and healthy volunteers. Materials and Methods. Using standardized questionnaires, the authors analyzed the incidence of side effects during high-frequency rTMS and within 24 hours after the procedure in 51 patients with various diseases of the nervous system and in 11 healthy volunteers. Results. The overall frequency of side effects was 59.5 % during stimulation and 50.2 % within 24 hours after the procedure. Serious side effects, which led to cessation of stimulation were recorded in 5 % of cases (n=3). They were associated with the syncope development (n=1) and severe headache (n=2). During rTMS, the most frequent manifestations of side effects were drowsiness (30.4 %), headache (25.8 %) and facial muscle contraction (14.7 %). Twenty-four hours after rTMS the most common manifestations were headache (15.7 %), mood changes (10.2 %) and mental alertness problems (9.4 %). It was found out, that headache was statistically more frequent at the beginning of the rTMS course. During rTMS, headache is often not so heavy and it is usually throbbing. However, within 24 hours after stimulation headache is usually moderate, pressing or dull. Conclusion. The obtained data confirm the importance of using standardized questionnaires for studying side effects and developing methods for their prevention and relief. Keywords: transcranial magnetic stimulation, non-invasive brain stimulation, safety, tolerance, side effects, headache, syncope.

Mechanisms and the Current State of Transcranial Magnetic Stimulation

CNS Spectrums ◽  
2003 ◽  
Vol 8 (7) ◽  
pp. 496-514 ◽  
Author(s):  
Mark S. George ◽  
Ziad Nahas ◽  
F. Andrew Kozel ◽  
Xingbao Li ◽  
Kaori Yamanaka ◽  
...  
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Brain Stimulation ◽  
Magnetic Stimulation ◽  
Functional Brain Imaging ◽  
New Developments ◽  
Magnetic Seizure Therapy ◽  
Non Invasive ◽  
Current State ◽  
Core Technology ◽  
Neuroscience Research

ABSTRACTTranscranial magnetic stimulation (TMS) is unique among the current brain stimulation techniques because it is relatively non-invasive. TMS markedly differs from vagus nerve stimulation, deep brain stimulation and magnetic seizure therapy, all of which require either an implanted prosthesis or general anesthesia, or both. Since its rebirth in its modern form in 1985, TMS has already shown potential usefulness in at least three important domains—as a basic neuroscience research instrument, as a potential clinical diagnostic tool, and as a therapy for several different neuropsychiatric conditions. The TMS scientific literature has now expanded beyond what a single summary article can adequately cover. This review highlights several new developments in combining TMS with functional brain imaging, using TMS as a psychiatric therapy, potentially using TMS to enhance performance, and finally recent advances in the core technology of TMS. TMS' ability to non-invasively and focally stimulate the brain of an awake human is proving to be a most important development for neuroscience in general, and neuropsychiatry in particular.

scholarly journals Modern concepts of the pathogenesis of obesity and new approaches to its correction

2018 ◽  
Vol 15 (2) ◽  
pp. 11-16
Author(s):  
Oksana V. Logvinova ◽  
Alexandra G. Poydasheva ◽  
Ilya S. Bakulin ◽  
Olga V. Lagoda ◽  
Elena I. Kremneva ◽  
...  
Keyword(s):  
Eating Disorders ◽  
Electrical Stimulation ◽  
Transcranial Magnetic Stimulation ◽  
Brain Stimulation ◽  
Magnetic Stimulation ◽  
Cellular Level ◽  
Transcranial Electrical Stimulation ◽  
Food Behavior ◽  
Physiological Mechanisms ◽  
Non Invasive

The present review considers modern concepts of the physiological mechanisms of the formation of food behavior in a norm at several levels, beginning with the cellular level and ending with the level of functional systems. Neuroimaging methods used for both the study of the pathophysiological foundations of eating disorders and for determining the target for neurostimulation techniques are described. Methods of non-invasive brain stimulation such as transcranial magnetic stimulation and transcranial electrical stimulation, the mechanisms of their influence and aspects of safety of application are reviewed, the latest data on the results of studies on the use of the above methods in the therapy of obesity are summarized.

scholarly journals Transcranial magnetic stimulation in exploring neurophysiology of cortical circuits and potential clinical implications

2021 ◽  
Vol 64 ◽  
pp. 244-257
Author(s):  
Kaviraja Udupa
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Psychiatric Disorders ◽  
Brain Stimulation ◽  
Magnetic Stimulation ◽  
Academic Research ◽  
Therapeutic Interventions ◽  
Cortical Circuits ◽  
Non Invasive ◽  
Technical Details ◽  
Exciting Area

Transcranial magnetic stimulation (TMS) is a non-invasive, painless technique to stimulate the human brain. Although it has been used in clinical research both as an investigative tool and treatment modality for the past three decades, its use has been restricted to tertiary health centres or higher-end academic research institutions. The aim of this review is to popularise the concepts of this effective non-invasive brain stimulation technique, further facilitating its use both in research and clinical practice among clinical physiologists. In the first part of this article, a brief physiologic overview of TMS will be provided with basic as well as the basic technical details. This is followed by a discussion of TMS parameters that can be studied using single and paired pulses of TMS which could be used to investigate the altered excitability of cortical circuits. Finally, how rTMS and patterned TMS could be used to induce plasticity which, in turn, could be potentially used as therapeutic interventions in various neurological and psychiatric disorders will be illustrated. In each section of this article, diagnostic as well as therapeutic utilities of TMS in Neurology and Psychiatric disorders will be discussed. These discussions could not only facilitate the understanding of pathophysiology of mood and movement disorders but also to manage various neurological and psychiatric disorders with novel therapeutic options. In the end, few future directions, limitations of this technique and comparison with other techniques will be provided. I hopefully, this review would elicit some interest in physiologists to take up this exciting area of brain stimulation as a research subject and work further on understanding the functions of brain and use it effectively in the management of various brain-related disorders.

scholarly journals Disparities in Acute Pain Treatment by Cognitive Status in Older Adults With Hip Fracture

2019 ◽  
Vol 75 (10) ◽  
pp. 2003-2007 ◽  
Author(s):  
Andrew K Chang ◽  
Robert R Edwards ◽  
R Sean Morrison ◽  
Charles Argoff ◽  
Ashar Ata ◽  
...  
Keyword(s):  
Older Adults ◽  
New York ◽  
Cognitive Impairment ◽  
Hip Fracture ◽  
Pain Treatment ◽  
Cognitive Status ◽  
Lower Amount ◽  
Cognitively Impaired ◽  
Intravenous Morphine ◽  
Morphine Equivalent

Abstract Background We examined the disparities in emergency department (ED) pain treatment based on cognitive status in older adults with an acute hip fracture. Methods Observational study in an academic ED in the Bronx, New York. One hundred forty-four adults aged 65 years and older with acute hip fracture were administered the Telephone Interview for Cognitive Status (TICS) while in the ED. The primary outcome was receipt of any parenteral analgesic. The risk factor of interest was cognitive impairment (TICS ≤ 25). Secondary outcomes included receipt of any opioid, receipt of any analgesic, total dose of analgesics in intravenous morphine equivalent units (MEQ), and time to receiving first analgesic. Results Of the 87 (60%) study patients who were cognitively impaired, 60% received a parenteral analgesic compared to 79% of the 57 cognitively unimpaired patients (RR 0.76 [95% CI 0.61, 0.94]). The effect of cognitive impairment on receiving any opioids (RR: 0.81, 95% CI 0.67, 0.98) and any analgesic (RR: 0.85; 95% CI: 0.71, 1.01) was similar. The median analgesic dose in cognitively impaired patients was significantly lower than in cognitively unimpaired patients (4 MEQ vs 8 MEQ, p = .003). Conclusion Among older adults presenting to the ED with acute hip fracture, cognitive impairment was independently associated with lower likelihood of receiving analgesia and lower amount of opioid analgesia.

Enhancing the effects of transcranial magnetic stimulation with intravenously injected magnetic nanoparticles

2019 ◽  
Vol 7 (6) ◽  
pp. 2297-2307 ◽  
Author(s):  
Rongrong Li ◽  
Jun Wang ◽  
Xiaoya Yu ◽  
Pengfei Xu ◽  
Shuai Zhang ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Transcranial Magnetic Stimulation ◽  
Brain Stimulation ◽  
Neurological Disorders ◽  
Magnetic Stimulation ◽  
Non Invasive ◽  
Stimulation Method ◽  
The Brain

Magnetic nanoparticles SPIONs are non-invasively introduced into the brain to enhance the effects of a non-invasive clinical brain stimulation method for treating neurological disorders.

Sign in / Sign up

Export Citation Format

Share Document