FLUCTUATIONS AND INTERACTIONS BETWEEN BRAIN WAVES DURING DEEP AND SHALLOW ANESTHESIA

2012 ◽  
Vol 11 (01) ◽  
pp. 1240018 ◽  
Author(s):  
B. MUSIZZA ◽  
F. F. BAJROVIĆ ◽  
J. PETROVČIČ ◽  
A. STEFANOVSKA ◽  
S. RIBARIČ

Using gold plated electrodes, inserted into the rat's head above the dura of the left and right parietal cortex, we recorded EEG during deep and shallow anesthesia with either pentobarbital (PB) or ketamine-xylazine (KX). The fluctuations in time series were then analyzed using wavelet transforms and the spectral power was determined within 7 frequency intervals (slow wave 2, S2, 0.0067–0.0167 Hz; slow wave 1, S1, 0.02–0.19 Hz; δ, 0.2–3.9 Hz; θ, 4–7.9 Hz; α, 8–12.9 Hz; β, 13–24.9 Hz and γ, 25–34.9 Hz). In addition, the coupling strengths between individual oscillatory components during deep and shallow anesthesia were evaluated for both anesthetics. We show specific changes for both anesthetics indicating that during deep anesthesia PB reduces high and low frequency activity (0.2–35 Hz) and enhances coupling especially between δ, θ and α waves, while KX reduces low frequency activity (0.005 to 0.2 Hz) and enhances coupling between frequency waves α, β and γ. Our results, using two anesthetics known to block different ion channels, provide an insight into brain dynamics and could have wide implications in creating biomarkers for detecting various neurophysiological modifications, such as in Alzheimer and Parkinson's disease or Autism spectrum disorder, as well as in providing more realistic models of brain dynamics.

2022 ◽  
Author(s):  
Arie Nakhmani ◽  
Joseph Olson ◽  
Zachary Irwin ◽  
Lloyd Edwards ◽  
Christopher Gonzalez ◽  
...  

Background: Dystonia is a prevalent yet under-studied motor feature of Parkinson disease (PD). Although considerable efforts have focused on brain oscillations related to the cardinal symptoms of PD, whether dystonia is associated with specific electrophysiological features is unclear. Objectives: To investigate subcortical and cortical field potentials at rest and during contralateral hand and foot movements in PD patients with versus without dystonia. Methods: We examined the prevalence and somatotopy of dystonia in PD patients undergoing deep brain stimulation (DBS) surgery. We recorded intracranial electrophysiology from sensorimotor cortex and directional DBS electrodes in subthalamic nucleus (STN), during both rest and voluntary contralateral limb movements. We used wavelet transforms and linear mixed models to characterize spectral content in patients with and without dystonia (n=25). Results: Dystonia was highly prevalent at enrollment (61%) and most common in the foot (78%). PD patients with dystonia display greater subthalamic theta and alpha power during movement (p < 0.05) but not at rest. Regardless of dystonia status, cortical recordings display prominent beta desynchronization (13-30 Hz) during movement, whereas STN signals show increases in spectral power at lower frequencies (4-20 Hz), with peaks at 6.0 +/- 3.3 and 4.2 +/- 2.9 Hz during hand and foot movements, respectively (p < 0.03). Conclusions: Whereas cortex was characterized by beta desynchronization during hand and foot movements similarly, STN showed limb-specific low frequency activity which was increased in PD patients with dystonia. These findings may help elucidate why PD-related dystonia is most common in the foot and help guide future closed-loop DBS devices.


1998 ◽  
Vol 275 (3) ◽  
pp. H946-H950 ◽  
Author(s):  
Hélène Otzenberger ◽  
Claude Gronfier ◽  
Chantal Simon ◽  
Anne Charloux ◽  
Jean Ehrhart ◽  
...  

We have recently demonstrated that the overnight profiles of cardiac interbeat autocorrelation coefficient of R-R intervals ( r RR) calculated at 1-min intervals are related to the changes in sleep electroencephalographic (EEG) mean frequency, which reflect depth of sleep. Other quantitative measures of the Poincaré plots, i.e., the standard deviation of normal R-R intervals (SDNN) and the root mean square difference among successive R-R normal intervals (RMSSD), are commonly used to evaluate heart rate variability. The present study was designed to compare the nocturnal profiles of r RR, SDNN, and RMSSD with the R-R spectral power components: high-frequency (HF) power, reflecting parasympathetic activity; low-frequency (LF) power, reflecting a predominance of sympathetic activity with a parasympathetic component; and the LF-to-HF ratio (LF/HF), regarded as an index of sympathovagal balance. r RR, SDNN, RMSSD, and the spectral power components were calculated every 5 min during sleep in 15 healthy subjects. The overnight profiles of r RR and LF/HF showed coordinate variations with highly significant correlation coefficients ( P < 0.001 in all subjects). SDNN correlated with LF power ( P < 0.001), and RMSSD correlated with HF power ( P < 0.001). The overnight profiles of r RR and EEG mean frequency were found to be closely related with highly cross-correlated coefficients ( P < 0.001). SDNN and EEG mean frequency were also highly cross correlated ( P < 0.001 in all subjects but 1). No systematic relationship was found between RMSSD and EEG mean frequency. In conclusion, r RR appears to be a new tool for evaluating the dynamic beat-to-beat interval behavior and the sympathovagal balance continuously during sleep. This nonlinear method may provide new insight into autonomic disorders.


2018 ◽  
Author(s):  
Qi Li ◽  
Adam J. Zaczek ◽  
Timothy M. Korter ◽  
J. Axel Zeitler ◽  
Michael T. Ruggiero

<div>Understanding the nature of the interatomic interactions present within the pores of metal-organic frameworks</div><div>is critical in order to design and utilize advanced materials</div><div>with desirable applications. In ZIF-8 and its cobalt analogue</div><div>ZIF-67, the imidazolate methyl-groups, which point directly</div><div>into the void space, have been shown to freely rotate - even</div><div>down to cryogenic temperatures. Using a combination of ex-</div><div>perimental terahertz time-domain spectroscopy, low-frequency</div><div>Raman spectroscopy, and state-of-the-art ab initio simulations,</div><div>the methyl-rotor dynamics in ZIF-8 and ZIF-67 are fully charac-</div><div>terized within the context of a quantum-mechanical hindered-</div><div>rotor model. The results lend insight into the fundamental</div><div>origins of the experimentally observed methyl-rotor dynamics,</div><div>and provide valuable insight into the nature of the weak inter-</div><div>actions present within this important class of materials.</div>


2020 ◽  
pp. 1-12
Author(s):  
Kimberly H. Wood ◽  
Adeel A. Memon ◽  
Raima A. Memon ◽  
Allen Joop ◽  
Jennifer Pilkington ◽  
...  

Background: Cognitive and sleep dysfunction are common non-motor symptoms in Parkinson’s disease (PD). Objective: Determine the relationship between slow wave sleep (SWS) and cognitive performance in PD. Methods: Thirty-two PD participants were evaluated with polysomnography and a comprehensive level II neurocognitive battery, as defined by the Movement Disorders Society Task Force for diagnosis of PD-mild cognitive impairment. Raw scores for each test were transformed into z-scores using normative data. Z-scores were averaged to obtain domain scores, and domain scores were averaged to determine the Composite Cognitive Score (CCS), the primary outcome. Participants were grouped by percent of SWS into High SWS and Low SWS groups and compared on CCS and other outcomes using 2-sided t-tests or Mann-Whitney U. Correlations of cognitive outcomes with sleep architecture and EEG spectral power were performed. Results: Participants in the High SWS group demonstrated better global cognitive function (CCS) (p = 0.01, effect size: r = 0.45). In exploratory analyses, the High SWS group showed better performance in domains of executive function (effect size: Cohen’s d = 1.05), language (d = 0.95), and processing speed (d = 1.12). Percentage of SWS was correlated with global cognition and executive function, language, and processing speed. Frontal EEG delta power during N3 was correlated with the CCS and executive function. Cognition was not correlated with subjective sleep quality. Conclusion: Increased SWS and higher delta spectral power are associated with better cognitive performance in PD. This demonstrates the significant relationship between sleep and cognitive function and suggests that interventions to improve sleep might improve cognition in individuals with PD.


2020 ◽  
Vol 20 (S11) ◽  
Author(s):  
Chao-Chen Chen ◽  
Fuchiang Rich Tsui

Abstract Background Electrocardiogram (ECG) signal, an important indicator for heart problems, is commonly corrupted by a low-frequency baseline wander (BW) artifact, which may cause interpretation difficulty or inaccurate analysis. Unlike current state-of-the-art approach using band-pass filters, wavelet transforms can accurately capture both time and frequency information of a signal. However, extant literature is limited in applying wavelet transforms (WTs) for baseline wander removal. In this study, we aimed to evaluate 5 wavelet families with a total of 14 wavelets for removing ECG baseline wanders from a semi-synthetic dataset. Methods We created a semi-synthetic ECG dataset based on a public QT Database on Physionet repository with ECG data from 105 patients. The semi-synthetic ECG dataset comprised ECG excerpts from the QT database superimposed with artificial baseline wanders. We extracted one ECG excerpt from each of 105 patients, and the ECG excerpt comprised 14 s of randomly selected ECG data. Twelve baseline wanders were manually generated, including sinusoidal waves, spikes and step functions. We implemented and evaluated 14 commonly used wavelets up to 12 WT levels. The evaluation metric was mean-square-error (MSE) between the original ECG excerpt and the processed signal with artificial BW removed. Results Among the 14 wavelets, Daubechies-3 wavelet and Symlets-3 wavelet with 7 levels of WT had best performance, MSE = 0.0044. The average MSEs for sinusoidal waves, step, and spike functions were 0.0271, 0.0304, 0.0199 respectively. For artificial baseline wanders with spikes or step functions, wavelet transforms in general had lower performance in removing the BW; however, WTs accurately located the temporal position of an impulse edge. Conclusions We found wavelet transforms in general accurately removed various baseline wanders. Daubechies-3 and Symlets-3 wavelets performed best. The study could facilitate future real-time processing of streaming ECG signals for clinical decision support systems.


2021 ◽  
pp. 003329412199102
Author(s):  
Ashleigh Hillier ◽  
Nataliya Poto ◽  
David Schena ◽  
Jessica Dorey ◽  
Abigail Buckingham ◽  
...  

There is considerable need to identify effective service provision models to support adults on the autism spectrum as they seek to lead independent lives. This study outlines an individualized life skills coaching program for adults with autism, “LifeMAP”, and the experiences and perspectives of the coaches. Responses on a tailored questionnaire provided detailed insight into how the coaches were performing their job, the strategies they utilized, reasons for client success and difficulty, challenges faced by the coaches, and ways they were supported by program staff. Coaches’ job self-efficacy and satisfaction were also examined. This study serves as a preliminary examination of individualized coaching for adults with autism from the coaches’ perspective.


2021 ◽  
pp. 030573562110089
Author(s):  
Melissa L Kirby ◽  
Karen Burland

Current research investigating the functions of music in everyday life has identified cognitive, emotional, and social functions of music. However, previous research focuses almost exclusively on neurotypical people and rarely considers the musical experiences of autistic people. In addition, there is limited research which focuses explicitly on the musical experiences of young people on the autism spectrum. Current research exploring the functions of music may therefore not accurately represent the experiences of the autistic community. This article aims to explore the function of music in the lives of young people on the autism spectrum through a series of interviews. Eleven young people on the autism spectrum age 12 to 25 ( M = 19.4) were interviewed about the function of music in their lives. An adaptive interview technique, utilizing multiple methods of communication, was employed to account for the participants’ broad communicative and personal needs. Interpretative phenomenological analysis revealed four key functions of music in the participants’ lives: Cognitive, Emotional, Social, and Identity. Collectively, these results provide a unique insight into the musical experiences of young people on the autism spectrum.


2021 ◽  
Vol 29 (3) ◽  
pp. 369-378
Author(s):  
Aleksej A. Nizov ◽  
Aleksej I. Girivenko ◽  
Mihail M. Lapkin ◽  
Aleksej V. Borozdin ◽  
Yana A. Belenikina ◽  
...  

BACKGROUND: The search for rational methods of primary, secondary, and tertiary prevention of coronary heart disease. To date, there are several publications on heart rate variability in ischemic heart disease. AIM: To study the state of the regulatory systems in the organism of patients with acute coronary syndrome without ST segment elevation based on the heart rhythm, and their relationship with the clinical, biochemical and instrumental parameters of the disease. MATERIALS AND METHODS: The open comparative study included 76 patients (62 men, 14 women) of mean age, 61.0 0.9 years, who were admitted to the Emergency Cardiology Department diagnosed of acute coronary syndrome without ST segment elevation. On admission, cardiointervalometry was performed using Varicard 2.51 apparatus, and a number of clinical and biochemical parameters were evaluated RESULTS: Multiple correlations of parameters of heart rate variability and clinical, biochemical and instrumental parameters were observed. From this, a cluster analysis of cardiointervalometry was performed, thereby stratifying patients into five clusters. Two extreme variants of dysregulation of the heart rhythm correlated with instrumental and laboratory parameters. A marked increase in the activity of the subcortical nerve centers (maximal increase of the spectral power in the very low frequency range with the underlying reduction of SDNN) in cluster 1 was associated with reduction of the left ventricular ejection fraction: cluster 147.0 [40.0; 49.0], cluster 260.0 [58.0; 64.0], cluster 360.0 [52.5; 64.5] % (the data are presented in the form of median and interquartile range; Me [Q25; Q75], p 0,05). Cluster 5 showed significant reduction in SDNN (monotonous rhythm), combined with increased level of creatine phosphokinase (CPC): cluster 5446,0 [186.0; 782.0], cluster 4141.0 [98.0; 204.0] IU/l; Me [Q25; Q75], p 0.05) and MВ-fraction of creatine phosphokinase; cluster 532.0 [15.0; 45.0], 4 cluster 412.0 [9.0; 18.0] IU/l; Me [Q25; Q75], p 0.05). CONCLUSIONS: In patients with acute coronary syndrome without ST segment elevation, cluster analysis of parameters of heart rate variability identified different peculiarities of regulation of the heart rhythm. Pronounced strain of the regulatory systems of the body was found to be associated with signs of severe pathology: the predominance of VLF (spectral power of the curve enveloping a dynamic range of cardiointervals in the very low frequency range) in spectral analysis with an underlying reduced SDNN is characteristic of patients with a reduced ejection fraction, and a monotonous rhythm is characteristic of patients with an increased level of creatine phosphokinase and MB-fraction of creatine phosphokinase.


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