459 results match your criteria Normal Awake EEG

Recovery of consciousness and cognition after general anesthesia in humans.

Elife 2021 05 10;10. Epub 2021 May 10.

Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States.

Understanding how the brain recovers from unconsciousness can inform neurobiological theories of consciousness and guide clinical investigation. To address this question, we conducted a multicenter study of 60 healthy humans, half of whom received general anesthesia for 3 hr and half of whom served as awake controls. We administered a battery of neurocognitive tests and recorded electroencephalography to assess cortical dynamics. Read More

View Article and Full-Text PDF

Temperature rhythms and ICU sleep: the TRIS study.

Minerva Anestesiol 2021 Apr 14. Epub 2021 Apr 14.

Thoracic Medicine Royal Brisbane and Women's Hospital, Herston, Australia.

Background: Core body temperature (CBT) patterns associated with sleep have not been described in the critically ill. This study aimed to characterise night-time sleep and its relationship to CBT in ICU patients.

Methods: A prospective study was performed in a 27-bed tertiary adult intensive care unit of 20 mechanically ventilated patients in the weaning stage of their critical illness. Read More

View Article and Full-Text PDF

Palinacousis: an eloquent symptom of temporal lobe lesion.

BMJ Case Rep 2021 Apr 13;14(4). Epub 2021 Apr 13.

Division of Neurosurgery, University of Montreal, Montreal, Quebec, Canada

A 24-year-old woman was referred to us for an intracranial haemorrhage in the left temporal lobe caused by a ruptured cavernous malformation; the bleeding extended over the left Heschl's gyrus and Wernicke area. On admission, the patient had global aphasia. A few days later, she spontaneously improved but remained with mild residual comprehensive dysphasia. Read More

View Article and Full-Text PDF

Abnormal patterns of sleep and EEG power distribution during non-rapid eye movement sleep in the sheep model of Huntington's disease.

Neurobiol Dis 2021 Jul 10;155:105367. Epub 2021 Apr 10.

Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge CB2 3DY, United Kingdom. Electronic address:

Sleep disruption is a common invisible symptom of neurological dysfunction in Huntington's disease (HD) that takes an insidious toll on well-being of patients. Here we used electroencephalography (EEG) to examine sleep in 6 year old OVT73 transgenic sheep (Ovis aries) that we used as a presymptomatic model of HD. We hypothesized that despite the lack of overt symptoms of HD at this age, early alterations of the sleep-wake pattern and EEG powers may already be present. Read More

View Article and Full-Text PDF

Contributions of synaptic and astrocyte physiology to the anaesthetised encephalogram revealed using a computational model.

Br J Anaesth 2021 May 24;126(5):985-995. Epub 2021 Mar 24.

Department of Anaesthesia, Waikato Clinical Campus, University of Auckland, Hamilton, New Zealand.

Background: General anaesthesia is known to enhance inhibitory synaptic transmission to produce characteristic effects on the EEG and reduction in brain metabolism secondary to reduced neuronal activity. Evidence suggests that anaesthesia might have a direct effect on synaptic metabolic processes, and this relates to anaesthesia sensitivity. We explored elements of synaptic transmission looking for possible contributions to the anaesthetised EEG and how it may modulate anaesthesia sensitivity. Read More

View Article and Full-Text PDF

Sonographic hypoechogenicity of brainstem raphe nucleus is correlated with electroencephalographic spike frequency in patients with epilepsy.

Epilepsy Behav 2021 04 11;117:107884. Epub 2021 Mar 11.

Department of Neurology, Epilepsy and Headache Group, the First Affiliated Hospital of Anhui Medical University, Jixi Road 218, Hefei 230022, China. Electronic address:

Background: Brainstem raphe nucleus (BRN) hypoechogenicity in transcranial sonography (TCS) has been demonstrated in patients with major depression, possibly representing a sonographic manifestation of serotonergic dysfunction in depression. Most patients with epilepsy with comorbid depression exhibit hypoechogenic BRN in TCS. However, the role of BRN in the pathogenesis of epilepsy is unclear. Read More

View Article and Full-Text PDF

Differential effects of propofol and ketamine on critical brain dynamics.

PLoS Comput Biol 2020 12 21;16(12):e1008418. Epub 2020 Dec 21.

Department of Physics, Indiana University, Bloomington, Indiana, USA.

Whether the brain operates at a critical "tipping" point is a long standing scientific question, with evidence from both cellular and systems-scale studies suggesting that the brain does sit in, or near, a critical regime. Neuroimaging studies of humans in altered states of consciousness have prompted the suggestion that maintenance of critical dynamics is necessary for the emergence of consciousness and complex cognition, and that reduced or disorganized consciousness may be associated with deviations from criticality. Unfortunately, many of the cellular-level studies reporting signs of criticality were performed in non-conscious systems (in vitro neuronal cultures) or unconscious animals (e. Read More

View Article and Full-Text PDF
December 2020

Are sleep paralysis and false awakenings different from REM sleep and from lucid REM sleep? A spectral EEG analysis.

J Clin Sleep Med 2021 Apr;17(4):719-727

Sleep Disorder Unit, Pitié-Salpêtrière University Hospital, AP-HP, Paris, France.

Study Objectives: To determine the polysomnography characteristics during sleep paralysis, false awakenings, and lucid dreaming (which are states intermediate to rapid eye movement [REM] sleep and wake but exceptionally observed in sleep laboratory).

Methods: In 5 participants, we captured 5 episodes of sleep paralysis (2 time marked with the ocular left-right-left-right code normally used to signal lucid dreaming, 1 time marked by an external noise, and 2 retrospectively reported) and 2 episodes of false awakening. The sleep coding (using 3-second mini-epochs) and spectral electroencephalography analysis were compared during these episodes and normal REM sleep as well as wakefulness in the same 4 of 5 participants and vs lucid REM sleep in 4 other patients with narcolepsy. Read More

View Article and Full-Text PDF

Epilepsy after congenital zika virus infection: EEG and neuroimaging features.

Seizure 2021 Jan 18;84:14-22. Epub 2020 Nov 18.

School of Medicine, Pontifícia Universidade Católica do Rio Grande do Sul, Brazil; Division of Clinical Research from the Brain Institute (BraIns), Brazil. Electronic address:

Purpose: To describe epilepsy after congenital Zika virus infection (ZIKV) and its relationship with structural neuroimaging findings.

Methods: This was a cross-sectional study in children (aged 13-42 months) who were born with microcephaly due to ZIKV infection between 2015-2017. Patients underwent a brain imaging scan (magnetic resonance) and a video-EEG study. Read More

View Article and Full-Text PDF
January 2021

The First Unprovoked Seizure in Typically Developing Children: A Real-Life Setting in Southern Brazil.

Clin EEG Neurosci 2020 Oct 13:1550059420965391. Epub 2020 Oct 13.

Department of Pediatrics, Neuropediatric Division, Federal University of Paraná, Curitiba, Brazil.

Aim: To describe the first unprovoked seizure in typically developing children, its clinical characteristics, recurrence rate, and possible risk factors in a real-life setting in Southern Brazil.

Method: In this retrospective cohort study, medical records of typically developing children aged 28 days to 14 years who had a first unprovoked seizure in a single tertiary care center were reviewed, in a 10-year period (2006-2016).

Results: Seventy-four children were included, 41 males and 33 females. Read More

View Article and Full-Text PDF
October 2020

Modulation of arousal and sleep/wake architecture by M PAM VU0453595 across young and aged rodents and nonhuman primates.

Neuropsychopharmacology 2020 12 31;45(13):2219-2228. Epub 2020 Aug 31.

Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.

Degeneration of basal forebrain cholinergic circuitry represents an early event in the development of Alzheimer's disease (AD). These alterations in central cholinergic function are associated with disruptions in arousal, sleep/wake architecture, and cognition. Changes in sleep/wake architecture are also present in normal aging and may represent a significant risk factor for AD. Read More

View Article and Full-Text PDF
December 2020

Decreased Alertness Reconfigures Cognitive Control Networks.

J Neurosci 2020 09 12;40(37):7142-7154. Epub 2020 Aug 12.

Cambridge Consciousness and Cognition Laboratory, Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom.

Humans' remarkable capacity to flexibly adapt their behavior based on rapid situational changes is termed cognitive control. Intuitively, cognitive control is thought to be affected by the state of alertness; for example, when drowsy, we feel less capable of adequately implementing effortful cognitive tasks. Although scientific investigations have focused on the effects of sleep deprivation and circadian time, little is known about how natural daily fluctuations in alertness in the regular awake state affect cognitive control. Read More

View Article and Full-Text PDF
September 2020

Nonlinear Analysis of Visually Normal EEGs to Differentiate Benign Childhood Epilepsy with Centrotemporal Spikes (BECTS).

Sci Rep 2020 05 21;10(1):8419. Epub 2020 May 21.

Computational Health Informatics Program, Boston Children's Hospital, Boston, USA.

Childhood epilepsy with centrotemporal spikes, previously known as Benign Epilepsy with Centro-temporal Spikes (BECTS) or Rolandic Epilepsy, is one of the most common forms of focal childhood epilepsy. Despite its prevalence, BECTS is often misdiagnosed or missed entirely. This is in part due to the nocturnal and brief nature of the seizures, making it difficult to identify during a routine electroencephalogram (EEG). Read More

View Article and Full-Text PDF

Electroencephalographic changes associated with subjective under- and overestimation of sleep duration.

Sleep 2020 11;43(11)

Center for Investigation and Research in Sleep, Lausanne University Hospital (CHUV), Lausanne, Switzerland.

Feeling awake although sleep recordings indicate clear-cut sleep sometimes occurs in good sleepers and to an extreme degree in patients with so-called paradoxical insomnia. It is unknown what underlies sleep misperception, as standard polysomnographic (PSG) parameters are often normal in these cases. Here we asked whether regional changes in brain activity could account for the mismatch between objective and subjective total sleep times (TST). Read More

View Article and Full-Text PDF
November 2020

Expanding the clinical and EEG spectrum of CNKSR2-related encephalopathy with status epilepticus during slow sleep (ESES).

Clin Neurophysiol 2020 05 13;131(5):1030-1039. Epub 2020 Feb 13.

Danish Epilepsy Centre, Dianalund, Denmark; University of Copenhagen, Copenhagen, Denmark. Electronic address:

Objective: To investigate the clinical and EEG features of Encephalopathy with Status Epilepticus during slow Sleep (ESES) related to CNKSR2 pathogenic variants.

Methods: Detailed clinical history, repeated wakefulness/overnight sleep EEGs, brain MRI were collected in five patients, including one female, with CNKSR2-related ESES.

Results: Neurodevelopment in infancy was normal in two patients, delayed in three. Read More

View Article and Full-Text PDF

The Inconsistent Nature of Heart Rate Variability During Sleep in Normal Children and Adolescents.

Front Cardiovasc Med 2020 21;7:19. Epub 2020 Feb 21.

Department of Respiratory and Sleep Medicine, Women's and Children's Hospital, Adelaide, SA, Australia.

Cardiac function is modulated by multiple factors including exogenous (circadian rhythm) and endogenous (ultradian 90-110 min sleep cycle) factors. By evaluating heart rate variability (HRV) during sleep, we will better understand their influence on cardiac activity. The aim of this study was to evaluate HRV in the dark phase of the circadian rhythm during sleep in healthy children and adolescents. Read More

View Article and Full-Text PDF
February 2020

Junior-Real Time neuropsychological testing (j-RTNT) for a young patient undergoing awake craniotomy.

Brain Cogn 2020 04 3;140:105535. Epub 2020 Feb 3.

Scientific Institute IRCCS "Eugenio Medea", Polo FVG, San Vito al Tagliamento (PN), Italy. Electronic address:

We developed a junior-real-time neuropsychological testing (j-RTNT) and used it during surgery of a right fronto-insular dysembryoplastic neuroepithelial tumor causing seizures in a 16 years old female. The j-RTNT included tasks from the battery NEPSY-II. Pre-surgery evaluation detected a below average performance in visuo-spatial planning, inhibition, visual attention, planning and borderline performance in speeded naming. Read More

View Article and Full-Text PDF

Weakly encoded memories due to acute sleep restriction can be rescued after one night of recovery sleep.

Sci Rep 2020 01 29;10(1):1449. Epub 2020 Jan 29.

Laboratory of Functional Neuroscience, Pablo de Olavide University, Seville, 41013, Spain.

Sleep is thought to play a complementary role in human memory processing: sleep loss impairs the formation of new memories during the following awake period and, conversely, normal sleep promotes the strengthening of the already encoded memories. However, whether sleep can strengthen deteriorated memories caused by insufficient sleep remains unknown. Here, we showed that sleep restriction in a group of participants caused a reduction in the stability of EEG activity patterns across multiple encoding of the same event during awake, compared with a group of participants that got a full night's sleep. Read More

View Article and Full-Text PDF
January 2020

First do no harm: Preventing harm and optimizing care in psychogenic nonepileptic seizures.

Epilepsy Behav 2020 01 20;102:106642. Epub 2019 Nov 20.

Weill Cornell Medicine, Department of Psychiatry, 1300 York Avenue, New York, NY 10065, United States; New York-Presbyterian Hospital Westchester Division, 21 Bloomingdale Road, White Plains, NY 10605, United States.

Psychogenic nonepileptic seizures (PNES) are challenging clinical occurrences consisting of any combination of altered movement, sensation, or awareness that resemble epileptic seizures (ES) but do not coincide with electrographic ictal discharges and are presumed to be neuropsychiatric-neurobehavioral in origin. Securing the PNES diagnosis is a crucial first step and is best confirmed by recording events on video-electroencephalogram (v-EEG) and finding an absence of ictal EEG changes and the presence of normal awake EEG rhythms before, during, and after the event. However, obstacles to timely diagnosis and referral to psychiatric treatment frequently occur, placing these patients at risk for harm from unnecessary medications and procedure as well as placing high burden on medical systems. Read More

View Article and Full-Text PDF
January 2020

Interictal epileptiform discharges on electroencephalography in children with methylenetetrahydrofolate reductase (MTHFR) polymorphisms.

Neurol Sci 2020 Mar 16;41(3):631-636. Epub 2019 Nov 16.

Department of Pediatric Metabolism, Faculty of Medicine, Mayıs University, Samsun, Turkey.

Objective: Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism. MTHFR C677T and A1298C polymorphisms are best-defined variants of MTHFR that were reported to be associated with epilepsy development. The aim of the study was to determine the incidence of interictal epileptiform discharges on electroencephalography (EEG) in asymptomatic children with C677T and A1298C polymorphisms who had no history of seizure. Read More

View Article and Full-Text PDF

Multi-band SWIFT enables quiet and artefact-free EEG-fMRI and awake fMRI studies in rat.

Neuroimage 2020 02 12;206:116338. Epub 2019 Nov 12.

A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland. Electronic address:

Functional magnetic resonance imaging (fMRI) studies in animal models provide invaluable information regarding normal and abnormal brain function, especially when combined with complementary stimulation and recording techniques. The echo planar imaging (EPI) pulse sequence is the most common choice for fMRI investigations, but it has several shortcomings. EPI is one of the loudest sequences and very prone to movement and susceptibility-induced artefacts, making it suboptimal for awake imaging. Read More

View Article and Full-Text PDF
February 2020

Fear-Related Signals in the Primary Visual Cortex.

Curr Biol 2019 12 24;29(23):4078-4083.e2. Epub 2019 Oct 24.

State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China. Electronic address:

Neuronal responses in the primary visual cortex (V1) are driven by simple stimuli, but these stimulus-evoked responses can be markedly modulated by non-sensory factors, such as attention and reward [1], and shaped by perceptual training [2]. In real-life situations, neutral visual stimuli can become emotionally tagged by experience, resulting in altered perceptual abilities to detect and discriminate these stimuli [3-5]. Human imaging [4] and electroencephalography (EEG) studies [6-9] have shown that visual fear learning (the acquisition of aversive emotion associated with a visual stimulus) affects the activities in visual cortical areas as early as in V1. Read More

View Article and Full-Text PDF
December 2019

The Odds Ratio Product (An Objective Sleep Depth Measure): Normal Values, Repeatability, and Change With CPAP in Patients With OSA.

J Clin Sleep Med 2019 08;15(8):1155-1163

Cerebra Health Inc., Winnipeg, Canada.

Study Objectives: The Odds Ratio Product (ORP) is an objective measure of sleep depth using the relationships of the powers of different electroencephalogram (EEG) frequencies in a single index. The range of the ORP is 0 (deeply asleep) to 2.5 (fully awake). Read More

View Article and Full-Text PDF

Normal Awake, Drowsy, and Sleep EEG Patterns That Might Be Overinterpreted as Abnormal.

J Clin Neurophysiol 2019 Jul;36(4):250-256

Department of Neurology, Jefferson Comprehensive Epilepsy Center, Thomas Jefferson University, Philadelphia, Pennsylvania, U.S.A.

Knowledge of normal patterns is essential for correct EEG interpretation. The overinterpretation of EEG (i.e. Read More

View Article and Full-Text PDF

Ripple-related firing of identified deep CA1 pyramidal cells in chronic temporal lobe epilepsy in mice.

Epilepsia Open 2019 Jun 4;4(2):254-263. Epub 2019 Mar 4.

Department of Neurosurgery Anschutz School of Medicine University of Colorado Denver Aurora Colorado.

Objective: Temporal lobe epilepsy (TLE) is often associated with memory deficits. Reactivation of memory traces in the hippocampus occurs during sharp-wave ripples (SWRs; 140-250 Hz). To better understand the mechanisms underlying high-frequency oscillations and cognitive comorbidities in epilepsy, we evaluated how rigorously identified deep CA1 pyramidal cells (dPCs) discharge during SWRs in control and TLE mice. Read More

View Article and Full-Text PDF

Functional brain connectivity in a rodent seizure model of autistic-like behavior.

Epilepsy Behav 2019 06 24;95:87-94. Epub 2019 Apr 24.

Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT 05405, USA. Electronic address:

Objective: There is increasing evidence that Autism Spectrum Disorder (ASD) is a disorder of functional connectivity with both human and rodent studies demonstrating alterations in connectivity. Here, we hypothesized that early-life seizures (ELS) in rats would interrupt normal brain connectivity and result in autistic-like behavior (ALB).

Methods: Following 50 seizures, adult rats were tested in the social interaction and social novelty tests and then underwent qualitative and quantitative intracranial electroencephalography (EEG) monitoring in the medial prefrontal cortex (PFC) and the hippocampal subfields, CA3 and CA1. Read More

View Article and Full-Text PDF

Childhood-only epilepsy with generalized tonic-clonic seizures: A well-defined epileptic syndrome.

Epilepsy Res 2019 07 27;153:28-33. Epub 2019 Mar 27.

Department of Neurology, Hospital de Pediatría "Prof. Dr. Juan P. Garrahan", Buenos Aires, Argentina.

Purpose: The aim of this study was to analyze patients whose only manifestation of epilepsy were generalized tonic-clonic seizures (GTCS) during childhood and discuss its validity as separate syndrome of childhood.

Methods: We included children with at least two unprovoked GTCS between 3 and 11 years of age, no other seizure types at diagnosis, normal psychomotor development and neurological examination, an EEG with normal background and paroxysms of generalized spikes and waves with a frequency 2.5 Hz or above, and an unknown cause for epilepsy. Read More

View Article and Full-Text PDF

Slit Ventricle Syndrome Leads to 10-Year History of Repetitive Transient Central Herniation Masquerading as Seizures: Hydrocephalus Case Report.

World Neurosurg 2019 06 1;126:134-138. Epub 2019 Mar 1.

Department of Neurosurgery, University of Wisconsin Hospital and Clinics, Madison, Wisconsin, USA.

Background: Slit-ventricle syndrome (SVS) is a recognized complication of ventricular shunt malfunction, resulting in cyclical symptoms without ventricular dilatation. We present a case of SVS with transient, repetitive, and progressive signs of brainstem herniation evidenced by pupillary dilatation, posturing, and unresponsiveness, with diffuse voltage attenuation on electroencephalogram (EEG).

Case Description: A 32-year-old female presented with a history of hydrocephalus and ventriculoperitoneal shunt placement at 9 months of age. Read More

View Article and Full-Text PDF

Phase-Dependent Suppression of Beta Oscillations in Parkinson's Disease Patients.

J Neurosci 2019 02 14;39(6):1119-1134. Epub 2018 Dec 14.

MRC Brain Network Dynamics Unit, Department of Pharmacology, University of Oxford, Oxford OX1 3TH, United Kingdom,

Synchronized oscillations within and between brain areas facilitate normal processing, but are often amplified in disease. A prominent example is the abnormally sustained beta-frequency (∼20 Hz) oscillations recorded from the cortex and subthalamic nucleus of Parkinson's disease patients. Computational modeling suggests that the amplitude of such oscillations could be modulated by applying stimulation at a specific phase. Read More

View Article and Full-Text PDF
February 2019

Complexity of Wake Electroencephalography Correlates With Slow Wave Activity After Sleep Onset.

Front Neurosci 2018 13;12:809. Epub 2018 Nov 13.

Division of Interdisciplinary Medicine and Biotechnology, Department of Medicine, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA, United States.

Sleep electroencephalography (EEG) provides an opportunity to study sleep scientifically, whose chaotic, dynamic, complex, and dissipative nature implies that non-linear approaches could uncover some mechanism of sleep. Based on well-established complexity theories, one hypothesis in sleep medicine is that lower complexity of brain waves at pre-sleep state can facilitate sleep initiation and further improve sleep quality. However, this has never been studied with solid data. Read More

View Article and Full-Text PDF
November 2018