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1.
Neuroimage ; 292: 120606, 2024 Apr 15.
Article En | MEDLINE | ID: mdl-38604538

Radon is a naturally occurring gas that contributes significantly to radiation in the environment and is the second leading cause of lung cancer globally. Previous studies have shown that other environmental toxins have deleterious effects on brain development, though radon has not been studied as thoroughly in this context. This study examined the impact of home radon exposure on the neural oscillatory activity serving attention reorientation in youths. Fifty-six participants (ages 6-14 years) completed a classic Posner cuing task during magnetoencephalography (MEG), and home radon levels were measured for each participant. Time-frequency spectrograms indicated stronger theta (3-7 Hz, 300-800 ms), alpha (9-13 Hz, 400-900 ms), and beta responses (14-24 Hz, 400-900 ms) during the task relative to baseline. Source reconstruction of each significant oscillatory response was performed, and validity maps were computed by subtracting the task conditions (invalidly cued - validly cued). These validity maps were examined for associations with radon exposure, age, and their interaction in a linear regression design. Children with greater radon exposure showed aberrant oscillatory activity across distributed regions critical for attentional processing and attention reorientation (e.g., dorsolateral prefrontal cortex, and anterior cingulate cortex). Generally, youths with greater radon exposure exhibited a reverse neural validity effect in almost all regions and showed greater overall power relative to peers with lesser radon exposure. We also detected an interactive effect between radon exposure and age where youths with greater radon exposure exhibited divergent developmental trajectories in neural substrates implicated in attentional processing (e.g., bilateral prefrontal cortices, superior temporal gyri, and inferior parietal lobules). These data suggest aberrant, but potentially compensatory neural processing as a function of increasing home radon exposure in areas critical for attention and higher order cognition.


Attention , Magnetoencephalography , Radon , Humans , Adolescent , Child , Male , Female , Radon/toxicity , Radon/adverse effects , Attention/radiation effects , Attention/physiology , Environmental Exposure/adverse effects , Brain/radiation effects , Brain Waves/radiation effects , Brain Waves/physiology , Brain Waves/drug effects , Orientation/physiology
2.
Epilepsy Res ; 202: 107359, 2024 May.
Article En | MEDLINE | ID: mdl-38582072

PURPOSE: In developmental and epileptic encephalopathy with spike-and-wave activation in sleep (DEE-SWAS), the thalamocortical network is suggested to play an important role in the pathophysiology of the progression from focal epilepsy to DEE-SWAS. Ethosuximide (ESM) exerts effects by blocking T-type calcium channels in thalamic neurons. With the thalamocortical network in mind, we studied the prediction of ESM effectiveness in DEE-SWAS treatment using phase-amplitude coupling (PAC) analysis. METHODS: We retrospectively enrolled children with DEE-SWAS who had an electroencephalogram (EEG) recorded between January 2009 and September 2022 and were prescribed ESM at Okayama University Hospital. Only patients whose EEG showed continuous spike-and-wave during sleep were included. We extracted 5-min non-rapid eye movement sleep stage N2 segments from EEG recorded before starting ESM. We calculated the modulation index (MI) as the measure of PAC in pair combination comprising one of two fast oscillation types (gamma, 40-80 Hz; ripples, 80-150 Hz) and one of five slow-wave bands (delta, 0.5-1, 1-2, 2-3, and 3-4 Hz; theta, 4-8 Hz), and compared it between ESM responders and non-responders. RESULTS: We identified 20 children with a diagnosis of DEE-SWAS who took ESM. Fifteen were ESM responders. Regarding gamma oscillations, significant differences were seen only in MI with 0.5-1 Hz slow waves in the frontal pole and occipital regions. Regarding ripples, ESM responders had significantly higher MI in coupling with all slow waves in the frontal pole region, 0.5-1, 3-4, and 4-8 Hz slow waves in the frontal region, 3-4 Hz slow waves in the parietal region, 0.5-1, 2-3, 3-4, and 4-8 Hz slow waves in the occipital region, and 3-4 Hz slow waves in the anterior-temporal region. SIGNIFICANCE: High MI in a wider area of the brain may represent the epileptic network mediated by the thalamus in DEE-SWAS and may be a predictor of ESM effectiveness.


Anticonvulsants , Electroencephalography , Ethosuximide , Sleep , Humans , Ethosuximide/therapeutic use , Ethosuximide/pharmacology , Male , Female , Electroencephalography/methods , Retrospective Studies , Anticonvulsants/therapeutic use , Anticonvulsants/pharmacology , Child, Preschool , Child , Sleep/drug effects , Sleep/physiology , Infant , Brain Waves/drug effects , Brain Waves/physiology , Thalamus/drug effects , Thalamus/physiopathology , Spasms, Infantile/drug therapy , Spasms, Infantile/physiopathology
3.
Trials ; 23(1): 890, 2022 Oct 22.
Article En | MEDLINE | ID: mdl-36273218

BACKGROUND: Attention deficit/hyperactivity disorder (ADHD) is the most common chronic mental and behavioral disorder among children. Some studies showed the lower levels of vitamin D in patients with ADHD compared with the healthy people. Few clinical trials were conducted in this field. The present study will be performed to examine the effect of vitamin D supplementation in children with ADHD. METHODS: We will conduct a double-blind, randomized controlled clinical trial to investigate the effect of vitamin D supplementation on brain waves, behavioral performance, serum nitric oxide, malondialdehyde, and high-sensitivity C-reactive protein in 50 patients with ADHD. The intervention group will receive one capsule 50,000 IU vitamin D every week, for 8 weeks. The control group will receive one placebo capsule containing 1000 mg olive oil every week. Electroencephalography will be performed for 10 min using Brain Master Discovery from 19 scalp sites both before the first intervention and the 10 sessions of the therapy. The artifact-free periods of 1-min electroencephalography data will be analyzed for quantitative electroencephalography measures. DISCUSSION: For the first time, this clinical trial will evaluate the effect of vitamin D supplementation on brain waves, serum nitric oxide, malondialdehyde, and high-sensitivity C-reactive protein in patients with ADHD. The results of the present clinical trial will provide a better vision about the vitamin D efficacy in patients with ADHD. TRIAL REGISTRATION: Registered on 5 November 2020 at Iranian Registry of Clinical Trials with code number IRCT20200922048802N1 ( https://www.irct.ir/trial/51410 ).


Attention Deficit Disorder with Hyperactivity , Dietary Supplements , Vitamin D , Child , Humans , Attention Deficit Disorder with Hyperactivity/drug therapy , Brain Waves/drug effects , C-Reactive Protein , Double-Blind Method , Iran , Malondialdehyde , Nitric Oxide , Randomized Controlled Trials as Topic , Treatment Outcome , Vitamin D/pharmacology
4.
Sci Rep ; 12(1): 2117, 2022 02 08.
Article En | MEDLINE | ID: mdl-35136089

Previous spectral analysis studies on insomnia have shown inconsistent results due to their heterogeneity and small sample sizes. We compared the difference of electroencephalogram (EEG) spectral power during sleep among participants without insomnia, insomniacs with no hypnotic use, hypnotic users with no insomnia complaints, and hypnotic users with insomnia complaints using the Sleep Heart Health Study data, which is large sample size and has good quality control. The fast Fourier transformation was used to calculate the EEG power spectrum for total sleep duration within contiguous 30-s epochs of sleep. For 1985 participants, EEG spectral power was compared among the groups while adjusting for potential confounding factors that could affect sleep EEG. The power spectra during total sleep differed significantly among the groups in all frequency bands (pcorr < 0.001). We found that quantitative EEG spectral power in the beta and sigma bands of total sleep differed (pcorr < 0.001) between participants without insomnia and hypnotic users with insomnia complaints after controlling for potential confounders. The higher beta and sigma power were found in the hypnotic users with insomnia complaints than in the non-insomnia participants. This study suggests differences in the microstructures of polysomnography-derived sleep EEG between the two groups.


Brain Waves/drug effects , Polysomnography , Sleep Aids, Pharmaceutical/therapeutic use , Sleep Initiation and Maintenance Disorders/drug therapy , Sleep, REM/drug effects , Adult , Aged , Case-Control Studies , Cohort Studies , Female , Humans , Male , Middle Aged , Sleep Aids, Pharmaceutical/pharmacology
5.
Sci Rep ; 12(1): 1919, 2022 02 04.
Article En | MEDLINE | ID: mdl-35121751

Robust biomarkers for anti-epileptic drugs (AEDs) activity in the human brain are essential to increase the probability of successful drug development. The frequency analysis of electroencephalographic (EEG) activity, either spontaneous or evoked by transcranial magnetic stimulation (TMS-EEG) can provide cortical readouts for AEDs. However, a systematic evaluation of the effect of AEDs on spontaneous oscillations and TMS-related spectral perturbation (TRSP) has not yet been provided. We studied the effects of Lamotrigine, Levetiracetam, and of a novel potassium channel opener (XEN1101) in two groups of healthy volunteers. Levetiracetam suppressed TRSP theta, alpha and beta power, whereas Lamotrigine decreased delta and theta but increased the alpha power. Finally, XEN1101 decreased TRSP delta, theta, alpha and beta power. Resting-state EEG showed a decrease of theta band power after Lamotrigine intake. Levetiracetam increased theta, beta and gamma power, while XEN1101 produced an increase of delta, theta, beta and gamma power. Spontaneous and TMS-related cortical oscillations represent a powerful tool to characterize the effect of AEDs on in vivo brain activity. Spectral fingerprints of specific AEDs should be further investigated to provide robust and objective biomarkers of biological effect in human clinical trials.


Anticonvulsants/pharmacology , Brain Waves/drug effects , Cerebral Cortex/drug effects , Electroencephalography , Lamotrigine/pharmacology , Levetiracetam/pharmacology , Organic Chemicals/pharmacology , Transcranial Magnetic Stimulation , Adult , Cerebral Cortex/physiology , Healthy Volunteers , Humans , Male , Young Adult
6.
Neuroimage ; 249: 118891, 2022 04 01.
Article En | MEDLINE | ID: mdl-35007718

Recent neuroimaging studies have demonstrated that spontaneous brain activity exhibits rich spatiotemporal structure that can be characterized as the exploration of a repertoire of spatially distributed patterns that recur over time. The repertoire of brain states may reflect the capacity for consciousness, since general anesthetics suppress and psychedelic drugs enhance such dynamics. However, the modulation of brain activity repertoire across varying states of consciousness has not yet been studied in a systematic and unified framework. As a unique drug that has both psychedelic and anesthetic properties depending on the dose, ketamine offers an opportunity to examine brain reconfiguration dynamics along a continuum of consciousness. Here we investigated the dynamic organization of cortical activity during wakefulness and during altered states of consciousness induced by different doses of ketamine. Through k-means clustering analysis of the envelope data of source-localized electroencephalographic (EEG) signals, we identified a set of recurring states that represent frequency-specific spatial coactivation patterns. We quantified the effect of ketamine on individual brain states in terms of fractional occupancy and transition probabilities and found that ketamine anesthesia tends to shift the configuration toward brain states with low spatial variability. Furthermore, by assessing the temporal dynamics of the occurrence and transitions of brain states, we showed that subanesthetic ketamine is associated with a richer repertoire, while anesthetic ketamine induces dynamic changes in brain state organization, with the repertoire richness evolving from a reduced level to one comparable to that of normal wakefulness before recovery of consciousness. These results provide a novel description of ketamine's modulation of the dynamic configuration of cortical activity and advance understanding of the neurophysiological mechanism of ketamine in terms of the spatial, temporal, and spectral structures of underlying whole-brain dynamics.


Anesthetics, Dissociative/pharmacology , Brain Waves/drug effects , Cerebral Cortex/drug effects , Consciousness/drug effects , Electroencephalography/methods , Ketamine/pharmacology , Wakefulness/drug effects , Adult , Anesthesia, General , Anesthetics, Dissociative/administration & dosage , Humans , Ketamine/administration & dosage
7.
Sci Rep ; 12(1): 114, 2022 01 07.
Article En | MEDLINE | ID: mdl-34997092

Microglia are subject to change in tandem with the endogenously generated biological oscillations known as our circadian rhythm. Studies have shown microglia harbor an intrinsic molecular clock which regulates diurnal changes in morphology and influences inflammatory responses. In the adult brain, microglia play an important role in the regulation of condensed extracellular matrix structures called perineuronal nets (PNNs), and it has been suggested that PNNs are also regulated in a circadian and diurnal manner. We sought to determine whether microglia mediate the diurnal regulation of PNNs via CSF1R inhibitor dependent microglial depletion in C57BL/6J mice, and how the absence of microglia might affect cortical diurnal gene expression rhythms. While we observe diurnal differences in microglial morphology, where microglia are most ramified at the onset of the dark phase, we do not find diurnal differences in PNN intensity. However, PNN intensity increases across many brain regions in the absence of microglia, supporting a role for microglia in the regulation of PNNs. Here, we also show that cortical diurnal gene expression rhythms are intact, with no cycling gene changes without microglia. These findings demonstrate a role for microglia in the maintenance of PNNs, but not in the maintenance of diurnal rhythms.


Brain Waves , Circadian Rhythm , Microglia/pathology , Nerve Net/pathology , Somatosensory Cortex/pathology , Animals , Brain Waves/drug effects , Circadian Rhythm/drug effects , Circadian Rhythm/genetics , Circadian Rhythm Signaling Peptides and Proteins/genetics , Circadian Rhythm Signaling Peptides and Proteins/metabolism , Gene Expression Regulation , Male , Mice, Inbred C57BL , Microglia/drug effects , Microglia/metabolism , Nerve Net/drug effects , Nerve Net/metabolism , Nerve Net/physiopathology , Organic Chemicals/pharmacology , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Somatosensory Cortex/drug effects , Somatosensory Cortex/metabolism , Somatosensory Cortex/physiopathology , Time Factors
8.
Nutr Neurosci ; 25(1): 159-168, 2022 Jan.
Article En | MEDLINE | ID: mdl-32116139

Objectives: Removing artificial food coloring (AFC) is a common dietary intervention for children with Attention-Deficit/Hyperactivity Disorder (ADHD), but has not been tested in young adults. This pilot study examined the effects of AFC on ADHD symptoms and electroencephalography (EEG) in college students with and without ADHD.Methods: At baseline, control and ADHD participants completed the Adult ADHD Self-Report Scale (ASRS), simple and complex attention measures, and resting-state EEG recordings. ADHD participants (n = 18) and a subset of controls (extended control group or EC, n = 11) avoided AFC in their diet for 2 weeks and then were randomized to a double-blind, placebo-controlled crossover challenge. Subjects received either 225 mg AFC disguised in chocolate cookies or placebo chocolate cookies for 3 days each week, with testing on the third day each week. Baseline comparisons were made using Student's t-test or Wilcoxon rank sum tests and challenge period analyses were run using General Linear Modeling.Results: The ADHD group had significantly greater scores on the ASRS (p < 0.001), confirming a symptom differential between groups; however, there were no differences in attentional measures or EEG at baseline. The AFC challenge resulted in an increase in posterior mean gamma power (p = 0.05), a decrease in posterior relative alpha power (p = 0.04), and a marginal increase in inattentive symptoms (p = 0.08) in the ADHD group. There were no effects of AFC in the EC group.Discussion: This study indicates that AFC exposure may affect brainwave activity and ADHD symptoms in college students with ADHD. Larger studies are needed to confirm these findings.


Attention Deficit Disorder with Hyperactivity/chemically induced , Attention Deficit Disorder with Hyperactivity/physiopathology , Electroencephalography , Food Coloring Agents/adverse effects , Pilot Projects , Brain Waves/drug effects , Brain Waves/physiology , Cross-Over Studies , Double-Blind Method , Humans , Students , Young Adult
9.
Clin Neurophysiol ; 134: 1-8, 2022 02.
Article En | MEDLINE | ID: mdl-34922194

OBJECTIVE: Phase-amplitude coupling between high-frequency (≥150 Hz) and delta (3-4 Hz) oscillations - modulation index (MI) - is a promising, objective biomarker of epileptogenicity. We determined whether sevoflurane anesthesia preferentially enhances this metric within the epileptogenic zone. METHODS: This is an observational study of intraoperative electrocorticography data from 621 electrodes chronically implanted into eight patients with drug-resistant, focal epilepsy. All patients were anesthetized with sevoflurane during resective surgery, which subsequently resulted in seizure control. We classified 'removed' and 'retained' brain sites as epileptogenic and non-epileptogenic, respectively. Mixed model analysis determined which anesthetic stage optimized MI-based classification of epileptogenic sites. RESULTS: MI increased as a function of anesthetic stage, ranging from baseline (i.e., oxygen alone) to 2.0 minimum alveolar concentration (MAC) of sevoflurane, preferentially at sites showing higher initial MI values. This phenomenon was accentuated just prior to sevoflurane reaching 2.0 MAC, at which time, the odds of a site being classified as epileptogenic were enhanced by 86.6 times for every increase of 1.0 MI. CONCLUSIONS: Intraoperative MI best localized the epileptogenic zone immediately before sevoflurane reaching 2.0 MAC in this small cohort of patients. SIGNIFICANCE: Prospective, large cohort studies are warranted to determine whether sevoflurane anesthesia can reduce the need for extraoperative, invasive evaluation.


Anesthetics, Inhalation/administration & dosage , Brain Waves/drug effects , Brain/drug effects , Drug Resistant Epilepsy/physiopathology , Epilepsies, Partial/physiopathology , Sevoflurane/administration & dosage , Adolescent , Anesthesia, General , Brain/physiopathology , Brain/surgery , Brain Waves/physiology , Child , Child, Preschool , Drug Resistant Epilepsy/surgery , Electrocorticography , Epilepsies, Partial/surgery , Humans , Neurosurgical Procedures , Prospective Studies , Young Adult
10.
Article En | MEDLINE | ID: mdl-34971723

BACKGROUND: Sub-anesthetic ketamine doses rapidly reduce depressive symptoms, although additional investigations of the underlying neural mechanisms and the prediction of response outcomes are needed. Electroencephalographic (EEG)-derived measures have shown promise in predicting antidepressant response to a variety of treatments, and are sensitive to ketamine administration. This study examined their utility in characterizing changes in depressive symptoms following single and repeated ketamine infusions. METHODS: Recordings were obtained from patients with treatment-resistant major depressive disorder (MDD) (N = 24) enrolled in a multi-phase clinical ketamine trial. During the randomized, double-blind, crossover phase (Phase 1), patients received intravenous ketamine (0.5 mg/kg) and midazolam (30 µg/kg), at least 1 week apart. For each medication, three resting, eyes-closed recordings were obtained per session (pre-infusion, immediately post-infusion, 2 h post-infusion), and changes in power (delta, theta1/2/total, alpha1/2/total, beta, gamma), alpha asymmetry, theta cordance, and theta source-localized anterior cingulate cortex activity were quantified. The relationships between ketamine-induced changes with early (Phase 1) and sustained (Phases 2,3: open-label repeated infusions) decreases in depressive symptoms (Montgomery-Åsberg Depression Rating Score, MADRS) and suicidal ideation (MADRS item 10) were examined. RESULTS: Both medications decreased alpha and theta immediately post-infusion, however, only midazolam increased delta (post-infusion), and only ketamine increased gamma (immediately post- and 2 h post-infusion). Regional- and frequency-specific ketamine-induced EEG changes were related to and predictive of decreases in depressive symptoms (theta, gamma) and suicidal ideation (alpha). Early and sustained treatment responders differed at baseline in surface-level and source-localized theta. CONCLUSIONS: Ketamine exerts frequency-specific changes on EEG-derived measures, which are related to depressive symptom decreases in treatment-resistant MDD and provide information regarding early and sustained individual response to ketamine. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: Action of Ketamine in Treatment-Resistant Depression, NCT01945047.


Analgesics/administration & dosage , Brain Waves/drug effects , Depressive Disorder, Treatment-Resistant/drug therapy , Electrophysiology , Gyrus Cinguli/drug effects , Ketamine/administration & dosage , Adult , Anesthetics, Intravenous/administration & dosage , Cross-Over Studies , Electroencephalography , Female , Humans , Infusions, Intravenous , Male , Midazolam/administration & dosage , Psychiatric Status Rating Scales
11.
Neuroimage ; 245: 118769, 2021 12 15.
Article En | MEDLINE | ID: mdl-34861394

The effects of hippocampal neuronal afterdischarges (nAD) on hemodynamic parameters, such as blood-oxygen-level-dependent (BOLD) signals) and local cerebral blood volume (CBV) changes, as well as neuronal activity and metabolic parameters in the dentate gyrus, was investigated in rats by combining in vivo electrophysiology with functional magnetic resonance imaging (fMRI) or 1H-nuclear magnetic resonance spectroscopy (1H-NMRS). Brief electrical high-frequency pulse-burst stimulation of the right perforant pathway triggered nAD, a seizure-like activity, in the right dentate gyrus with a high incidence, a phenomenon that in turn caused a sustained decrease in BOLD signals for more than 30 min. The decrease was associated with a reduction in CBV but not with signs of hypoxic metabolism. nAD also triggered transient changes mainly in the low gamma frequency band that recovered within 20 min, so that the longer-lasting altered hemodynamics reflected a switch in blood supply rather than transient changes in ongoing neuronal activity. Even in the presence of reduced baseline BOLD signals, neurovascular coupling mechanisms remained intact, making long-lasting vasospasm unlikely. Subsequently generated nAD did not further alter the baseline BOLD signals. Similarly, nAD did not alter baseline BOLD signals when acetaminophen was previously administered, because acetaminophen alone had already caused a similar decrease in baseline BOLD signals as observed after the first nAD. Thus, at least two different blood supply states exist for the hippocampus, one low and one high, with both states allowing similar neuronal activity. Both acetaminophen and nAD switch from the high to the low blood supply state. As a result, the hemodynamic response function to an identical stimulus differed after nAD or acetaminophen, although the triggered neuronal activity was similar.


Brain Waves/physiology , Electrocorticography , Hippocampus/physiology , Magnetic Resonance Imaging , Neuroimaging , Neurovascular Coupling/physiology , Proton Magnetic Resonance Spectroscopy , Seizures/physiopathology , Animals , Brain Waves/drug effects , Disease Models, Animal , Hippocampus/drug effects , Male , Neurovascular Coupling/drug effects , Rats , Rats, Wistar , Seizures/metabolism
12.
Sci Rep ; 11(1): 22716, 2021 11 22.
Article En | MEDLINE | ID: mdl-34811404

Spectral power density (SPD) indexed by electroencephalogram (EEG) recordings has recently gained attention in elucidating neural mechanisms of chronic pain syndromes and medication use. We compared SPD variations between 15 fibromyalgia (FM) women in use of opioid in the last three months (73.33% used tramadol) with 32 non-users. EEG data were obtained with Eyes Open (EO) and Eyes Closed (EC) resting state. SPD peak amplitudes between EO-EC were smaller in opioid users in central theta, central beta, and parietal beta, and at parietal delta. However, these variations were positive for opioid users. Multivariate analyses of variance (ANOVAs) revealed that EO-EC variations in parietal delta were negatively correlated with the disability due to pain, and central and parietal beta activity variations were positively correlated with worse sleep quality. These clinical variables explained from 12.5 to 17.2% of SPD variance. In addition, central beta showed 67% sensitivity / 72% specificity and parietal beta showed 73% sensitivity/62% specificity in discriminating opioid users from non-users. These findings suggest oscillations in EEG might be a sensitive surrogate marker to screen FM opioid users and a promising tool to understand the effects of opioid use and how these effects relate to functional and sleep-related symptoms.


Analgesics, Opioid/therapeutic use , Brain Mapping , Brain Waves/drug effects , Brain/drug effects , Electroencephalography , Fibromyalgia/drug therapy , Rest , Adult , Brain/physiopathology , Cross-Sectional Studies , Female , Fibromyalgia/diagnosis , Fibromyalgia/physiopathology , Humans , Middle Aged , Predictive Value of Tests , Signal Processing, Computer-Assisted , Time Factors
13.
Neuroimage ; 245: 118659, 2021 12 15.
Article En | MEDLINE | ID: mdl-34767940

Studying changes in cortical oscillations can help elucidate the mechanistic link between receptor physiology and the clinical effects of anaesthetic drugs. Propofol, a GABA-ergic drug produces divergent effects on visual cortical activity: increasing induced gamma-band responses (GBR) while decreasing evoked responses. Dexmedetomidine, an α2- adrenergic agonist, differs from GABA-ergic sedatives both mechanistically and clinically as it allows easy arousability from deep sedation with less cognitive side-effects. Here we use magnetoencephalography (MEG) to characterize and compare the effects of GABA-ergic (propofol) and non-GABA-ergic (dexmedetomidine) sedation, on visual and motor cortical oscillations. Sixteen male participants received target-controlled infusions of propofol and dexmedetomidine, producing mild-sedation, in a placebo-controlled, cross-over study. MEG data was collected during a combined visuomotor task. The key findings were that propofol significantly enhanced visual stimulus induced GBR (44% increase in amplitude) while dexmedetomidine decreased it (40%). Propofol also decreased the amplitudes of the Mv100 (visual M100) (27%) and Mv150 (52%) visual evoked fields (VEF), whilst dexmedetomidine had no effect on these. During the motor task, neither drug had any significant effect on movement related gamma synchrony (MRGS), movement related beta de-synchronisation (MRBD) or Mm100 (movement-related M100) movement-related evoked fields (MEF), although dexmedetomidine slowed the Mm300. Dexmedetomidine increased (92%) post-movement beta synchronisation/rebound (PMBR) power while propofol reduced it (70%, statistically non- significant). Overall, dexmedetomidine and propofol, at equi-sedative doses, produce contrasting effects on visual induced GBR, VEF, PMBR and MEF. These findings provide a mechanistic link between the known receptor physiology of these sedative drugs with their known clinical effects and may be used to explore mechanisms of other anaesthetic drugs on human consciousness.


Brain Waves/drug effects , Dexmedetomidine/pharmacology , Hypnotics and Sedatives/pharmacology , Magnetoencephalography/methods , Motor Cortex/drug effects , Propofol/pharmacology , Adult , Conscious Sedation , Consciousness/drug effects , Cross-Over Studies , Humans , Male , Movement/physiology , Wakefulness , Young Adult
14.
Parkinsonism Relat Disord ; 92: 26-32, 2021 11.
Article En | MEDLINE | ID: mdl-34666272

INTRODUCTION: Levodopa has become the main therapy for motor symptoms of Parkinson's disease (PD). This study aimed to test whether the amplitude of low-frequency fluctuation (ALFF) computed by fMRI could predict individual patient's response to levodopa treatment. METHODS: We included 40 patients. Treatment efficacy was defined based on motor symptoms improvement from the state of medication off to medication on, as assessed by the Unified Parkinson's Disease Rating Scale score III. Two machine learning models were constructed to test the prediction ability of ALFF. First, the ensemble method was implemented to predict individual treatment responses. Second, the categorical boosting (CatBoost) classification was used to predict individual levodopa responses in patients classified as moderate and superior responders, according to the 50% threshold of improvement. The age, disease duration and treatment dose were controlled as covariates. RESULTS: No significant difference in clinical data were observed between moderate and superior responders. Using the ensemble method, the regression model showed a significant correlation between the predicted and the observed motor symptoms improvement (r = 0.61, p < 0.01, mean absolute error = 0.11 ± 0.02), measured as a continuous variable. The use of the Catboost algorithm revealed that ALFF was able to differentiate between moderate and superior responders (area under the curve = 0.90). The mainly contributed regions for both models included the bilateral primary motor cortex, the occipital cortex, the cerebellum, and the basal ganglia. CONCLUSION: Both continuous and binary ALFF values have the potential to serve as promising predictive markers of dopaminergic therapy response in patients with PD.


Antiparkinson Agents/therapeutic use , Drug Monitoring/methods , Levodopa/therapeutic use , Magnetic Resonance Imaging/statistics & numerical data , Parkinson Disease/drug therapy , Aged , Brain/diagnostic imaging , Brain Mapping , Brain Waves/drug effects , Female , Humans , Male , Middle Aged , Parkinson Disease/diagnostic imaging , Predictive Value of Tests , Reproducibility of Results , Treatment Outcome
15.
Clin Neurophysiol ; 132(12): 3010-3018, 2021 12.
Article En | MEDLINE | ID: mdl-34715426

OBJECTIVE: Ketamine is an anesthetic drug associated with dissociation. Decreased electroencephalogram alpha (8-13 Hz) and low-beta (13-20 Hz) oscillation power have been associated with ketamine-induced dissociation. We aimed to characterize surface electroencephalogram signatures that may serve as biomarkers for dissociation. METHODS: We analyzed data from a single-site, open-label, high-density surface electroencephalogram study of ketamine anesthesia (2 mg/kg, n = 15). We assessed dissociation longitudinally using the Clinician Administered Dissociation States Scale (CADSS) and administered midazolam to attenuate dissociation and enable causal inference. We analyzed electroencephalogram power and global coherence with multitaper spectral methods. Mixed effects models were used to assess whether power and global coherence signatures of ketamine could be developed into dissociation-specific biomarkers. RESULTS: Compared to baseline, ketamine unresponsiveness was associated with increased frontal power between 0.5 to 9.3 Hz, 12.2 to 16.6 Hz, and 24.4 to 50 Hz. As subjects transitioned into a responsive but dissociated state (mean CADSS ± SD, 22.1 ± 17), there was a decrease in power between 0.5 to 10.3 Hz and 11.7 to 50 Hz. Midazolam reduced dissociation scores (14.3 ± 11.6), decreased power between 4.4 to 11.7 Hz and increased power between 14.2 to 50 Hz. Our mixed-effects model demonstrated a quadratic relationship between time and CADSS scores. When models (frontal power, occipital power, global coherence) were reanalyzed with midazolam and electroencephalogram features as covariates, only midazolam was retained. CONCLUSIONS: Ketamine is associated with structured electroencephalogram power and global coherence signatures that may enable principled anesthetic state but not dissociation monitoring. SIGNIFICANCE: A neurophysiological biomarker for dissociation may lead to a better understanding of neuropsychiatric disorders.


Anesthetics, Dissociative/pharmacology , Brain Waves/drug effects , Brain/drug effects , Ketamine/pharmacology , Adult , Brain/physiology , Brain Waves/physiology , Electroencephalography , Female , Humans , Male , Young Adult
16.
Biomed Pharmacother ; 143: 112146, 2021 Nov.
Article En | MEDLINE | ID: mdl-34507113

Epilepsy is the most common neurological disorder, affecting nearly 50 million people worldwide. The condition can be manifested either due to genetic predisposition or acquired from acute insult which leads to alteration of cellular and molecular mechanisms. Evaluating the latest and the current knowledge in regard to the mechanisms underlying molecular and cellular alteration, hyperexcitability is a consequence of an imbalanced state wherein enhance excitatory glutamatergic and reduced inhibitory GABAergic signaling is considered to be accountable for seizures associated damage. However, neurodegeneration contributing to epileptogenesis has become increasingly appreciated. The components at the helm of neurodegenerative alterations during epileptogenesis include GABAergic neuronal and receptor changes, neuroinflammation, alteration in axonal transport, oxidative stress, excitotoxicity, and other cellular as well as functional changes. Targeting neurodegeneration with vitamin E as an antioxidant, anti-inflammatory and neuroprotective may prove to be one of the therapeutic approaches useful in managing epilepsy. In this review, we discuss and converse about the seizure-induced episodes as a link for the development of neurodegenerative and pathological consequences of epilepsy. We also put forth a summary of the potential intervention with vitamin E therapy in the management of epilepsy.


Anticonvulsants/therapeutic use , Brain Waves/drug effects , Brain/drug effects , Epilepsy/drug therapy , Nerve Degeneration , Neurodegenerative Diseases/drug therapy , Neuroprotective Agents/therapeutic use , Vitamin E/therapeutic use , Animals , Anti-Inflammatory Agents/therapeutic use , Anticonvulsants/adverse effects , Antioxidants/therapeutic use , Brain/metabolism , Brain/physiopathology , Epilepsy/epidemiology , Epilepsy/metabolism , Epilepsy/physiopathology , Humans , Inflammation Mediators/metabolism , Neurodegenerative Diseases/epidemiology , Neurodegenerative Diseases/metabolism , Neurodegenerative Diseases/physiopathology , Neuroprotective Agents/adverse effects , Oxidative Stress/drug effects , Prognosis , Risk Assessment , Risk Factors , Signal Transduction , Vitamin E/adverse effects
17.
J Neurophysiol ; 126(4): 1265-1275, 2021 Oct 01.
Article En | MEDLINE | ID: mdl-34469699

The electroencephalogram (EEG) provides an objective, neural correlate of consciousness. Opioid receptors modulate mammalian neuronal excitability, and this fact was used to characterize how opioids administered to mice alter EEG power and states of consciousness. The present study tested the hypothesis that antinociceptive doses of fentanyl, morphine, or buprenorphine differentially alter the EEG and states of sleep and wakefulness in adult, male C57BL/6J mice. Mice were anesthetized and implanted with telemeters that enabled wireless recordings of cortical EEG and electromyogram (EMG). After surgical recovery, EEG and EMG were used to objectively score states of consciousness as wakefulness, rapid eye movement (REM) sleep, or non-REM (NREM) sleep. Measures of EEG power (dB) were quantified as δ (0.5-4 Hz), θ (4-8 Hz), α (8-13 Hz), σ (12-15 Hz), ß (13-30 Hz), and γ (30-60 Hz). Compared with saline (control), fentanyl and morphine decreased NREM sleep, morphine eliminated REM sleep, and buprenorphine eliminated NREM sleep and REM sleep. Opioids significantly and differentially disrupted the temporal organization of sleep/wake states, altered specific EEG frequency bands, and caused dissociated states of consciousness. The results are discussed relative to the fact that opioids, pain, and sleep modulate interacting states of consciousness.NEW & NOTEWORTHY This study discovered that antinociceptive doses of fentanyl, morphine, and buprenorphine significantly and differentially disrupt EEG-defined states of consciousness in C57BL/6J mice. These data are noteworthy because: 1) buprenorphine is commonly used in medication-assisted therapy for opioid addiction, and 2) there is evidence that disordered sleep can promote addiction relapse. The results contribute to community phenotyping efforts by making publicly available all descriptive and inferential statistics from this study (Supplemental Tables S1-S8).


Analgesics, Opioid/pharmacology , Analgesics/pharmacology , Brain Waves/drug effects , Buprenorphine/pharmacology , Consciousness/drug effects , Dissociative Disorders/chemically induced , Electrocorticography/drug effects , Fentanyl/pharmacology , Morphine/pharmacology , Sleep Stages/drug effects , Wakefulness/drug effects , Analgesics/administration & dosage , Analgesics, Opioid/administration & dosage , Animals , Buprenorphine/administration & dosage , Disease Models, Animal , Electroencephalography , Electromyography , Fentanyl/administration & dosage , Male , Mice , Mice, Inbred C57BL , Morphine/administration & dosage
18.
Hum Brain Mapp ; 42(16): 5446-5457, 2021 11.
Article En | MEDLINE | ID: mdl-34464488

People with HIV (PWH) use cannabis at a higher rate than the general population, but the influence on neural activity is not well characterized. Cannabis use among PWH may have a beneficial effect, as neuroinflammation is known to be a critical problem in PWH and cannabis use has been associated with a reduction in proinflammatory markers. Thus, it is important to understand the net impact of cannabis use on brain and cognitive function in PWH. In this study, we collected magnetoencephalographic (MEG) brain imaging data on 81 participants split across four demographically matched groups (i.e., PWH using cannabis, controls using cannabis, non-using PWH, and non-using controls). Participants completed a visuospatial processing task during MEG. Time-frequency resolved voxel time series were extracted to identify the dynamics of oscillatory and pre-stimulus baseline neural activity. Our results indicated strong theta (4-8 Hz), alpha (10-16 Hz), and gamma (62-72 Hz) visual oscillations in parietal-occipital brain regions across all participants. PWH exhibited significant behavioral deficits in visuospatial processing, as well as reduced theta oscillations and elevated pre-stimulus gamma activity in visual cortices, all of which replicate prior work. Strikingly, chronic cannabis use was associated with a significant reduction in pre-stimulus gamma activity in the visual cortices, such that PWH no longer statistically differed from controls. These results provide initial evidence that cannabis use may normalize some neural aberrations in PWH. This study fills an important gap in understanding the impact of cannabis use on brain and cognitive function in PWH.


Brain Waves , Cannabinoid Receptor Modulators/pharmacology , Cognitive Dysfunction , HIV Infections/complications , Medical Marijuana/pharmacology , Visual Cortex , Visual Perception , Adult , Brain Waves/drug effects , Brain Waves/physiology , Cognitive Dysfunction/drug therapy , Cognitive Dysfunction/physiopathology , Female , Humans , Magnetoencephalography , Male , Middle Aged , Visual Cortex/drug effects , Visual Cortex/physiology , Visual Perception/drug effects , Visual Perception/physiology
19.
Nutrients ; 13(8)2021 Aug 19.
Article En | MEDLINE | ID: mdl-34445005

Caffeine, a natural stimulant, is known to be effective for weight loss. On this basis, we screened the arousal-inducing effect of five dietary supplements with a weight loss effect (Garcinia cambogia, Coleus forskohlii, Camellia sinensis L., Irvingia gabonensis, and Malus pumila M.), of which the G. cambogia peel extract (GC) showed a significant arousal-inducing effect in the pentobarbital-induced sleep test in mice. This characteristic of GC was further evaluated by analysis of electroencephalogram and electromyogram in C57L/6N mice, and it was compared to that of the positive control, caffeine. Administration of GC (1500 mg/kg) significantly increased wakefulness and decreased non-rapid eye movement sleep, similar to that of caffeine (25 mg/kg), with GC and caffeine showing a significant increase in wakefulness at 2 and 6 h, respectively. Compared to that of caffeine, the shorter duration of efficacy of GC could be advantageous because of the lower possibility of sleep disturbance. Furthermore, the arousal-inducing effects of GC (1500 mg/kg) and caffeine (25 mg/kg) persisted throughout the chronic (3 weeks) administration study. This study, for the first time, revealed the arousal-inducing effect of GC. Our findings suggest that GC might be a promising natural stimulant with no side effects. In addition, it is preferential to take GC as a dietary supplement for weight loss during the daytime to avoid sleep disturbances owing to its arousal-inducing effect.


Arousal/drug effects , Brain Waves/drug effects , Brain/drug effects , Central Nervous System Stimulants/pharmacology , Electroencephalography , Garcinia cambogia , Plant Extracts/pharmacology , Animals , Anti-Obesity Agents/pharmacology , Brain/physiology , Caffeine/pharmacology , Central Nervous System Stimulants/isolation & purification , Fruit , Garcinia cambogia/chemistry , Hypnotics and Sedatives/pharmacology , Male , Mice, Inbred C57BL , Mice, Inbred ICR , Pentobarbital/pharmacology , Plant Extracts/isolation & purification , Sleep/drug effects
20.
Molecules ; 26(10)2021 May 15.
Article En | MEDLINE | ID: mdl-34063337

The functional food market is growing with a compound annual growth rate of 7.9%. Thai food recipes use several kinds of herbs. Lemongrass, garlic, and turmeric are ingredients used in Thai curry paste. Essential oils released in the preparation step create the flavor and fragrance of the famous tom yum and massaman dishes. While the biological activities of these ingredients have been investigated, including the antioxidant, anti-inflammatory, and antimicrobial activities, there is still a lack of understanding regarding the responses to the essential oils of these plants. To investigate the effects of essential oil inhalation on the brain and mood responses, electroencephalography was carried out during the non-task resting state, and self-assessment of the mood state was performed. The essential oils were prepared in several dilutions in the range of the supra-threshold level. The results show that Litsea cubeba oil inhalation showed a sedative effect, observed from alpha and beta wave power reductions. The frontal and temporal regions of the brain were involved in the wave alterations. Garlic oil increased the alpha wave power at lower concentrations; however, a sedative effect was also observed at higher concentrations. Lower dilution oil induced changes in the fast alpha activity in the frontal region. The alpha and beta wave powers were decreased with higher dilution oils, particularly in the temporal, parietal, and occipital regions. Both Litsea cubeba and turmeric oils resulted in better positive moods than garlic oil. Garlic oil caused more negative moods than the others. The psychophysiological activities and the related brain functions require further investigation. The knowledge obtained from this study may be used to design functional food products.


Affect/drug effects , Curcuma/chemistry , Frontal Lobe/physiology , Garlic/chemistry , Litsea/chemistry , Oils, Volatile/administration & dosage , Temporal Lobe/physiology , Administration, Inhalation , Brain Waves/drug effects , Dose-Response Relationship, Drug , Electroencephalography , Female , Frontal Lobe/drug effects , Functional Food/analysis , Functional Food/economics , Gas Chromatography-Mass Spectrometry , Healthy Volunteers , Humans , Hypnotics and Sedatives/administration & dosage , Hypnotics and Sedatives/chemistry , Hypnotics and Sedatives/pharmacology , Odorants , Oils, Volatile/chemistry , Oils, Volatile/pharmacology , Plant Oils/administration & dosage , Plant Oils/chemistry , Plant Oils/pharmacology , Rest/physiology , Temporal Lobe/drug effects , Thailand , Young Adult
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