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Sample records for benign eeg patterns

  1. ANOMALIES ON EEG IN PATIENTS WITH COGNITIVE EPILEPTIFORM DISINTEGRATION AND EPILEPTIC ENCEPHALOPATHIES, ASSOCIATED WITH С BENIGN EPILEPTIFORM PATTERNS OF CHILDHOOD

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    M. B. Mironov

    2012-01-01

    Full Text Available On background of review and discussion of current scientific literature è own data the article presents the main clinical characteristics and anomalies on EEG in patients with cognitive epileptiform disintegration and epileptic encephalopathies, associated with ñ benign epileptiform patterns of childhood. The author describes in detail EEGpatterns — continuous spike and wave activity during sleep and benign epileptiform patterns of childhood, the role of these patterns and their special features in different syndromes of cognitive epileptiform disintegration. The article illustrated own data of the author.

  2. Intellectual and language findings and their relationship to EEG characteristics in benign childhood epilepsy with centrotemporal spikes.

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    Riva, Daria; Vago, Chiara; Franceschetti, Silvana; Pantaleoni, Chiara; D'Arrigo, Stefano; Granata, Tiziana; Bulgheroni, Sara

    2007-03-01

    Recent research has revealed that benign childhood epilepsy with centrotemporal spikes (BECTS) causes deficient performance in various neuropsychological areas, without arriving at a definition of a uniform profile. The purpose of this study was to examine intelligence and certain language functions in 24 children with an active centrotemporal focus, comparing them with a group of 16 controls matched for age and schooling. Test results were correlated with several EEG characteristics, including focal versus multifocal presentation of interictal epileptiform activity, lateralization, spike maximum on midtemporal or extratemporal electrodes, and rate of interictal activity when awake and during non-REM sleep. Our study demonstrated that children with BECTS have mild language defects, revealed by tests measuring phonemic fluency, verbal re-elaboration of semantic knowledge, and lexical comprehension. Interictal EEG discharges demonstrated that a high rate of occurrence while awake, multifocal location, and temporal prominence seem to impair the efficiency of some of the neuropsychological functions investigated. However, because the last EEG was obtained within the last 2 months (on average) before the assessment, and because BECTS is a form of epilepsy with signs of cortical hyperexcitability that vary over time in terms of rate, side, and location, the pattern of neuropsychological deficiencies could have changed (at least to some degree) by the time of the test, with respect to the EEG variables considered.

  3. The Colorful Brain: Visualization of EEG Background Patterns

    NARCIS (Netherlands)

    Putten, van Michel J.A.M

    2008-01-01

    This article presents a method to transform routine clinical EEG recordings to an alternative visual domain. The method is intended to support the classic visual interpretation of the EEG background pattern and to facilitate communication about relevant EEG characteristics. In addition, it provides

  4. The colorful brain: visualization of EEG background patterns.

    Science.gov (United States)

    van Putten, Michel J A M

    2008-04-01

    This article presents a method to transform routine clinical EEG recordings to an alternative visual domain. The method is intended to support the classic visual interpretation of the EEG background pattern and to facilitate communication about relevant EEG characteristics. In addition, it provides various quantitative features. The EEG features used in the transformation include color-coded time-frequency representations of two novel symmetry measures and a synchronization measure, based on a nearest-neighbor coherence estimate. This triplet captures three highly relevant aspects of the dynamics of the EEG background pattern, which correlate strongly with various neurologic conditions. In particular, it quantifies and visualizes the spatiotemporal distribution of the EEG power in the anterioposterior and lateral direction, and the short-distance coherence. The potential clinical use is illustrated by application of the proposed technique to various normal and abnormal EEGs, including seizure activity and the transition to sleep. The proposed transformation visualizes various essential elements of EEG background patterns. Quantitative analysis of clinical EEG recordings and transformation to alternative domains assists in the interpretation and contributes to an objective interpretation.

  5. Quantitative EEG Applying the Statistical Recognition Pattern Method

    DEFF Research Database (Denmark)

    Engedal, Knut; Snaedal, Jon; Hoegh, Peter

    2015-01-01

    BACKGROUND/AIM: The aim of this study was to examine the discriminatory power of quantitative EEG (qEEG) applying the statistical pattern recognition (SPR) method to separate Alzheimer's disease (AD) patients from elderly individuals without dementia and from other dementia patients. METHODS...

  6. Pattern Recognition of EEG Signals and Applications in Robotics

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-dong; CHENG Zhi-qiang; LI De-jun

    2006-01-01

    With the rapid development of brain computer interface (simply called BCI),electroencephalography (EEG) will be another interesting bio-electrical signal applied in robotics after EMG.In order to realize it finally,the accurate measurement and pattern recognition of EEG signal must be a very important and elementary research objective.Based on our current researches and some reports from the other international colleagues in the field,we deeply discuss the basic characteristics of EEG signal,the development and selection of EEG measurement system,feature extraction and recognition methods of EEG signal,and then review EEG's applications in robotics as well as the future research trends in this paper.

  7. EEG

    Science.gov (United States)

    Electroencephalogram; Brain wave test; Epilepsy - EEG; Seizure - EEG ... The test is done by an electroencephalogram (EEG) technologist in your doctor's office or at a hospital or laboratory. The test is done in the following way: You lie on your ...

  8. Hanging-induced burst suppression pattern in EEG

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    Nilgun Cinar

    2012-01-01

    Full Text Available Lethal suspension (hanging is one of the most common methods of attempting suicide. Spinal fractures, cognitive and motor deficits as well as epileptic seizures can be detected after unsuccessful hanging attempts. Introduced here is the case of a 25-year-old man exemplifying the clinical observations stated hereafter, who was conveyed to our emergency room after having survived attempted suicide by hanging, with his post-anoxic burst-suppression electroencephalography (BS-EEG pattern and clinical diagnoses in the post-comatose stage. The patient′s state of consciousness was gradually improved over a period of time. His neuropsychiatric assessment proved that memory deficit, a slight lack of attention and minor executive dysfunction was observed a month after the patient was discharged. Although the BS-EEG pattern indicates severe brain dysfunction, it is a poor prognostic factor; rarely, patients survive with minor cognitive deficits and can perform their normal daily activities.

  9. Detection of burst suppression patterns in EEG using recurrence rate.

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    Liang, Zhenhu; Wang, Yinghua; Ren, Yongshao; Li, Duan; Voss, Logan; Sleigh, Jamie; Li, Xiaoli

    2014-01-01

    Burst suppression is a unique electroencephalogram (EEG) pattern commonly seen in cases of severely reduced brain activity such as overdose of general anesthesia. It is important to detect burst suppression reliably during the administration of anesthetic or sedative agents, especially for cerebral-protective treatments in various neurosurgical diseases. This study investigates recurrent plot (RP) analysis for the detection of the burst suppression pattern (BSP) in EEG. The RP analysis is applied to EEG data containing BSPs collected from 14 patients. Firstly we obtain the best selection of parameters for RP analysis. Then, the recurrence rate (RR), determinism (DET), and entropy (ENTR) are calculated. Then RR was selected as the best BSP index one-way analysis of variance (ANOVA) and multiple comparison tests. Finally, the performance of RR analysis is compared with spectral analysis, bispectral analysis, approximate entropy, and the nonlinear energy operator (NLEO). ANOVA and multiple comparison tests showed that the RR could detect BSP and that it was superior to other measures with the highest sensitivity of suppression detection (96.49%, P = 0.03). Tracking BSP patterns is essential for clinical monitoring in critically ill and anesthetized patients. The purposed RR may provide an effective burst suppression detector for developing new patient monitoring systems.

  10. Detection of Burst Suppression Patterns in EEG Using Recurrence Rate

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    Zhenhu Liang

    2014-01-01

    Full Text Available Burst suppression is a unique electroencephalogram (EEG pattern commonly seen in cases of severely reduced brain activity such as overdose of general anesthesia. It is important to detect burst suppression reliably during the administration of anesthetic or sedative agents, especially for cerebral-protective treatments in various neurosurgical diseases. This study investigates recurrent plot (RP analysis for the detection of the burst suppression pattern (BSP in EEG. The RP analysis is applied to EEG data containing BSPs collected from 14 patients. Firstly we obtain the best selection of parameters for RP analysis. Then, the recurrence rate (RR, determinism (DET, and entropy (ENTR are calculated. Then RR was selected as the best BSP index one-way analysis of variance (ANOVA and multiple comparison tests. Finally, the performance of RR analysis is compared with spectral analysis, bispectral analysis, approximate entropy, and the nonlinear energy operator (NLEO. ANOVA and multiple comparison tests showed that the RR could detect BSP and that it was superior to other measures with the highest sensitivity of suppression detection (96.49%,  P=0.03. Tracking BSP patterns is essential for clinical monitoring in critically ill and anesthetized patients. The purposed RR may provide an effective burst suppression detector for developing new patient monitoring systems.

  11. Which EEG patterns in coma are nonconvulsive status epilepticus?

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    Trinka, Eugen; Leitinger, Markus

    2015-08-01

    Nonconvulsive status epilepticus (NCSE) is common in patients with coma with a prevalence between 5% and 48%. Patients in deep coma may exhibit epileptiform EEG patterns, such as generalized periodic spikes, and there is an ongoing debate about the relationship of these patterns and NCSE. The purposes of this review are (i) to discuss the various EEG patterns found in coma, its fluctuations, and transitions and (ii) to propose modified criteria for NCSE in coma. Classical coma patterns such as diffuse polymorphic delta activity, spindle coma, alpha/theta coma, low output voltage, or burst suppression do not reflect NCSE. Any ictal patterns with a typical spatiotemporal evolution or epileptiform discharges faster than 2.5 Hz in a comatose patient reflect nonconvulsive seizures or NCSE and should be treated. Generalized periodic diacharges or lateralized periodic discharges (GPDs/LPDs) with a frequency of less than 2.5 Hz or rhythmic discharges (RDs) faster than 0.5 Hz are the borderland of NCSE in coma. In these cases, at least one of the additional criteria is needed to diagnose NCSE (a) subtle clinical ictal phenomena, (b) typical spatiotemporal evolution, or (c) response to antiepileptic drug treatment. There is currently no consensus about how long these patterns must be present to qualify for NCSE, and the distinction from nonconvulsive seizures in patients with critical illness or in comatose patients seems arbitrary. The Salzburg Consensus Criteria for NCSE [1] have been modified according to the Standardized Terminology of the American Clinical Neurophysiology Society [2] and validated in three different cohorts, with a sensitivity of 97.2%, a specificity of 95.9%, and a diagnostic accuracy of 96.3% in patients with clinical signs of NCSE. Their diagnostic utility in different cohorts with patients in deep coma has to be studied in the future. This article is part of a Special Issue entitled "Status Epilepticus".

  12. Short-Term EEG Spectral Pattern as a Single Event in EEG Phenomenology

    OpenAIRE

    Fingelkurts, Al. A; Fingelkurts, An. A

    2010-01-01

    Spectral decomposition, to this day, still remains the main analytical paradigm for the analysis of EEG oscillations. However, conventional spectral analysis assesses the mean characteristics of the EEG power spectra averaged out over extended periods of time and/or broad frequency bands, thus resulting in a “static” picture which cannot reflect adequately the underlying neurodynamic. A relatively new promising area in the study of EEG is based on reducing the signal to elementary short-term ...

  13. Fibronectin Pattern in Benign Hyperplasia and Cancer of the Prostate

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    Miroslava M. Janković

    2008-01-01

    Full Text Available Fibronectin (FN is a multifunctional glycoprotein involved in cell-matrix interactions. It exhibits a complex pattern of forms differing in respect to aminoacid and oligosaccharide composition. In this study we examined glycobiochemical and functional properties of the FN in benign prostatic hyperplasia (BPH and prostatic cancer (PCa, attempting to resolve disease-related differences. Two BPH sera pools and three PCa sera pools were used as the FN source. The affinity-purified molecule was characterized by SDS-PAGE, immuno- and lectin blot, lectin-affinity chromatography and adhesion assay. BPH FN existed as intact molecule, giving the main immunoreactive band at 220 kDa. In contrast, PCa FN comprised three main immunoreactive fragments of 140, 110 and 90 kDa. As for glycosylation the ratio of altogether lectin-reactive PCa FN was different from that of BPH FN manifested as a decrease of Con A- and an increase of LCA-reactive moieties. Fibroblasts adhered to both FN preparations in a concentration dependent manner, but with a significantly lower efficiency to PCa FN. The results obtained showing distinct structural characteristics of PCa FN compared to BPH FN could be important for modulation of its ligand and recognition properties expressed as gain or loss of functions or as specific markers of its origin.

  14. Detecting stable phase structures in EEG signals to classify brain activity amplitude patterns

    Institute of Scientific and Technical Information of China (English)

    Yusely RUIZ; Guang LI; Walter J. FREEMAN; Eduardo GONZALEZ

    2009-01-01

    Obtaining an electrocorticograms (ECoG) signal requires an invasive procedure in which brain activity is recorded from the cortical surface. In contrast, obtaining electroencephalograms (EEG) recordings requires the non-invasive procedure of recording the brain activity from the scalp surface, which allows EEG recordings to be performed more easily on healthy humans. In this work, a technique previously used to study spatial-temporal patterns of brain activity on animal ECoG was adapted for use on EEG. The main issues are centered on solving the problems introduced by the increment on the interelectrode distance and the procedure to detect stable frames. The results showed that spatial patterns of beta and gamma activity can also be extracted from the EEG signal by using stable frames as time markers for feature extraction. This adapted technique makes it possible to take advantage of the cognitive and phenomenological awareness of a normal healthy subject.

  15. An Approach for Pattern Recognition of EEG Applied in Prosthetic Hand Drive

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    Xiao-Dong Zhang

    2011-12-01

    Full Text Available For controlling the prosthetic hand by only electroencephalogram (EEG, it has become the hot spot in robotics research to set up a direct communication and control channel between human brain and prosthetic hand. In this paper, the EEG signal is analyzed based on multi-complicated hand activities. And then, two methods of EEG pattern recognition are investigated, a neural prosthesis hand system driven by BCI is set up, which can complete four kinds of actions (arm’s free state, arm movement, hand crawl, hand open. Through several times of off-line and on-line experiments, the result shows that the neural prosthesis hand system driven by BCI is reasonable and feasible, the C-support vector classifiers-based method is better than BP neural network on the EEG pattern recognition for multi-complicated hand activities.

  16. Clinical and imaging correlates of EEG patterns in hospitalized patients with encephalopathy.

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    Sutter, Raoul; Stevens, Robert D; Kaplan, Peter W

    2013-04-01

    To identify the relationship between pathologic electroencephalographic (EEG) patterns, clinical and neuroradiological abnormalities, and outcome in hospitalized patients with acute encephalopathy. This 5-year cohort study was performed at an academic tertiary care center. EEGs in 154 patients with altered mental status were classified according to five predefined patterns: Isolated continuous slowing of background activity (theta, theta/delta, and delta activity) and patterns with slowing background activity with episodic transients [i.e., triphasic waves (TWs) or frontal intermittent delta activity (FIRDA)]. Clinical characteristics, blood tests and neuroimaging were compared among groups. Associations between EEG patterns and structural and non-structural abnormalities were calculated. Glasgow Outcome Score >3 at discharge was defined as favorable and 1-3 as unfavorable outcome. In multivariable analyses, theta was associated with brain atrophy (OR 2.6, p = 0.020), theta/delta with intracerebral hemorrhages (OR 6.8, p = 0.005), FIRDA with past cerebrovascular accidents (OR 2.7, p = 0.004), TWs with liver or multi-organ failure (OR 6, p = 0.004; OR 4, p = 0.039), and delta activity with alcohol/drug abuse with or without intoxication, and HIV infection (OR 3.8, p = 0.003; OR 9, p = 0.004). TWs were associated with death (OR 4.5, p = 0.005); theta/delta with unfavorable outcomes (OR 2.5, p = 0.033), while patients with FIRDA had favorable outcomes (OR 4.8, p = 0.004). In encephalopathic patients, well-defined EEG patterns are associated with specific pathological conditions and outcomes, suggesting that mechanistic hypotheses underlie these abnormal EEG patterns. To clarify the respective contributions of non-structural and structural abnormalities to encephalopathy reflected in specific EEG patterns, prospective studies using continuous EEG monitoring during the acute onset of encephalopathy are needed.

  17. Standardized EEG interpretation accurately predicts prognosis after cardiac arrest

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    Rossetti, Andrea O.; van Rootselaar, Anne-Fleur; Wesenberg Kjaer, Troels; Horn, Janneke; Ullén, Susann; Friberg, Hans; Nielsen, Niklas; Rosén, Ingmar; Åneman, Anders; Erlinge, David; Gasche, Yvan; Hassager, Christian; Hovdenes, Jan; Kjaergaard, Jesper; Kuiper, Michael; Pellis, Tommaso; Stammet, Pascal; Wanscher, Michael; Wetterslev, Jørn; Wise, Matt P.; Cronberg, Tobias

    2016-01-01

    Objective: To identify reliable predictors of outcome in comatose patients after cardiac arrest using a single routine EEG and standardized interpretation according to the terminology proposed by the American Clinical Neurophysiology Society. Methods: In this cohort study, 4 EEG specialists, blinded to outcome, evaluated prospectively recorded EEGs in the Target Temperature Management trial (TTM trial) that randomized patients to 33°C vs 36°C. Routine EEG was performed in patients still comatose after rewarming. EEGs were classified into highly malignant (suppression, suppression with periodic discharges, burst-suppression), malignant (periodic or rhythmic patterns, pathological or nonreactive background), and benign EEG (absence of malignant features). Poor outcome was defined as best Cerebral Performance Category score 3–5 until 180 days. Results: Eight TTM sites randomized 202 patients. EEGs were recorded in 103 patients at a median 77 hours after cardiac arrest; 37% had a highly malignant EEG and all had a poor outcome (specificity 100%, sensitivity 50%). Any malignant EEG feature had a low specificity to predict poor prognosis (48%) but if 2 malignant EEG features were present specificity increased to 96% (p EEG was found in 1% of the patients with a poor outcome. Conclusions: Highly malignant EEG after rewarming reliably predicted poor outcome in half of patients without false predictions. An isolated finding of a single malignant feature did not predict poor outcome whereas a benign EEG was highly predictive of a good outcome. PMID:26865516

  18. Cd117 and Cd34 Staining Patterns in Childhood Benign Mammary Lesions

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    Ayper KAÇAR

    2012-01-01

    Full Text Available Objective: CD117 and CD34 are markers that have both been implied in cancer progression in adult breast lesions. This study was conducted in order to create a retrospective documentation and to analyze the expression patterns of these markers on childhood benign lesions along with a comparison with adult breast lesions’ staining patterns.Material and Method: Nine fibroadenomas, 2 tubular adenomas, 1 mammary hamartoma, 2 gynecomastias, 1 benign phyllodes tumor were retrieved from pathology archives of two reference centers between 2005-2010.Results: CD117 staining was identified in the epithelium of all cases in fibroadenoma/tubular adenoma group and focally positive in 1 mammary hamartoma, 2 gynecomastias, and 1 benign phyllodes tumor. CD117 staining was detected in the stroma of 8 cases. Three fibroadenomas, 1 mammary hamartoma, 2 gynecomastias and 1 benign phyllodes tumor lacked stromal labelling for this marker. All cases were strongly and diffusely positive for CD34 except the benign phyllodes tumor case. This case presented marked loss of stromal CD34 staining when compared to the surrounding stroma. Additionally, pseudoangiomatous stromal hyperplasia was noted in 2 gynecomastias and in the peritumoral stroma of benign phyllodes tumor case.Conclusion: Our study demonstrated that fibroadenoma was the most commonly encountered breast lesion in childhood and that adolescent fibroadenomas showed similar staining patterns for CD117 and CD34 as for adult counterparts. On the other hand, different expression patterns of CD117 and CD34 between adenoma group and the gynecomastias and benign phyllodes tumor group may implicate different mechanisms of development and tumorigenesis among these groups.

  19. A three-dimensional spatio-temporal EEG pattern analyzing system

    Institute of Scientific and Technical Information of China (English)

    LIU Hesheng; GAO Xiaorong; YANG Fusheng

    2003-01-01

    Spatio-temporal pattern analysis of EEG is an important tool in brain research. An EEG pattern analysis system based on a hierarchical multi-method approach is proposed here. The system consists of multiple steps including extraction of target signal, acquisition of intracranial electric activity distribution, adaptive segmentation of EEG and spatio-temporal pattern recognition. Some modern signal processing methods such as common spatial subspace decomposition, hidden Markov model are adopted. This paper also proposes an algorithm named LORETA-FOCUSS to estimate the current density inside the brain with a high spatial resolution. Microstate analysis of EEG is extended to the 3-D situation. The system was applied to the brain computer interface problem and achieved the highest accuracy of 88.89% with an average accuracy of 81.48% when classifying two imaginary movement tasks, while the data were not manually pre-selected. The result has proved spatio-temporal EEG pattern analysis is an efficient way in brain research.

  20. EEG frequency patterns associated with hallucinations in schizophrenia and "creativity" in normals.

    Science.gov (United States)

    Whitton, J L; Moldofsky, H; Lue, F

    1978-02-01

    This study attempts to define EEG power spectral patterns associated with hallucinatory behaviors in schizophrenia. Six unmedicated schizophrenics with Schneiderian criteria were interviewed and their tongue potentials were monitored and recorded on FM tape. Eye movements and tongue potentials were monitored and segments with artifacts were not used. Consecutive 4-sec intervals of EEG were analyzed in the frequency domain using fast Fourier transorm methods and serial power spectra plots obtained. The intrusiveness of the hallucinatory experience may be similar to the sudden internal experience of perceptual resolution in a creative task. Six normal controls were similarly monitored and analyzed while responding to tests of "creativity." In the 4-sec interval prior to reports of hallucinatory experiences, a frequency pattern of predominatly delta and theta power was found in 71.7% of the EEG segments. In the control group, 78.1% of the EEG segments preceding a creative response demonstrated a similar low frequency pattern which also differed significantly from the base line EEG frequency pattern.

  1. Patterns of EEG Activity in Individuals with Autism Spectrum Disorders

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    Zhukova M.A.,

    2016-10-01

    Full Text Available The article reviews most recent findings on neural activity in children and adults with autism spectrum disorders (ASD. Most of the studies demonstrate decreased connectivity in cortical regions, excitatory/inhibitory imbalance and atypical processing of language in people with ASD. It is argued that difficulties in semantic integration are connected to selective insensitivity to language, which is manifested in atypical N400 ERP component. In the article we analyze the data suggesting a strong relationship between ASD and epilepsy and argue that the comorbidity is more prevalent among individuals who have cognitive dysfunction. The EEG profile of people with ASD suggests U-shaped alterations with excess in high- and low-frequency EEG bands. We critically analyze the “broken mirror” hypothesis of ASD and demonstrate findings which challenge this theory.

  2. Spatial patterning of the neonatal EEG suggests a need for a high number of electrodes.

    Science.gov (United States)

    Odabaee, Maryam; Freeman, Walter J; Colditz, Paul B; Ramon, Ceon; Vanhatalo, Sampsa

    2013-03-01

    There is an increasing demand for source analysis of neonatal EEG, but currently there is inadequate knowledge about i) the spatial patterning of neonatal scalp EEG and hence ii) the number of electrodes needed to capture neonatal EEG in full spatial detail. This study addresses these issues by using a very high density (2.5mm interelectrode spacing) linear electrode array to assess the spatial power spectrum, by using a high density (64 electrodes) EEG cap to assess the spatial extent of the common oscillatory bouts in the neonatal EEG and by using a neonatal size spherical head model to assess the effects of source depth and skull conductivities on the spatial frequency spectrum. The linear array recordings show that the spatial power spectrum decays rapidly until about 0.5-0.8 cycles per centimeter. The dense array EEG recordings show that the amplitude of oscillatory events decays within 4-6 cm to the level of global background activity, and that the higher frequencies (12-20 Hz) show the most rapid spatial decline in amplitude. Simulation with spherical head model showed that realistic variation in skull conductivity and source depths can both introduce orders of magnitude difference in the spatial frequency of the scalp EEG. Calculation of spatial Nyquist frequencies from the spatial power spectra suggests that an interelectrode distance of about 6-10mm would suffice to capture the full spatial texture of the raw EEG signal at the neonatal scalp without spatial aliasing or under-sampling. The spatial decay of oscillatory events suggests that a full representation of their spatial characteristics requires an interelectrode distance of 10-20mm. The findings show that the conventional way of recording neonatal EEG with about 10 electrodes ignores most spatial EEG content, that increasing the electrode density is necessary to improve neonatal EEG source localization and information extraction, and that prospective source models will need to carefully consider the

  3. Are you really looking? Finding the answer through fixation patterns and EEG

    NARCIS (Netherlands)

    Brouwer, A.-M.; Hogervorst, M.A.; Herman, P.; Kooi, F.

    2009-01-01

    Eye movement recordings do not tell us whether observers are 'really looking' or whether they are paying attention to something else than the visual environment. We want to determine whether an observer's main current occupation is visual or not by investigating fixation patterns and EEG. Subjects w

  4. fMRI activation patterns in an analytic reasoning task: consistency with EEG source localization

    Science.gov (United States)

    Li, Bian; Vasanta, Kalyana C.; O'Boyle, Michael; Baker, Mary C.; Nutter, Brian; Mitra, Sunanda

    2010-03-01

    Functional magnetic resonance imaging (fMRI) is used to model brain activation patterns associated with various perceptual and cognitive processes as reflected by the hemodynamic (BOLD) response. While many sensory and motor tasks are associated with relatively simple activation patterns in localized regions, higher-order cognitive tasks may produce activity in many different brain areas involving complex neural circuitry. We applied a recently proposed probabilistic independent component analysis technique (PICA) to determine the true dimensionality of the fMRI data and used EEG localization to identify the common activated patterns (mapped as Brodmann areas) associated with a complex cognitive task like analytic reasoning. Our preliminary study suggests that a hybrid GLM/PICA analysis may reveal additional regions of activation (beyond simple GLM) that are consistent with electroencephalography (EEG) source localization patterns.

  5. 伴中央颞部棘波的良性儿童癫痫脑电图分析%Analysis of EEG and clinical of benign childhood epilepsy with centrotemporal spikes

    Institute of Scientific and Technical Information of China (English)

    袁彬; 牛仁山

    2009-01-01

    Objective To analyse the meaning of EEG in benign childhood epilepsy with of centrahemporal spikes diagnosis. Methods EEG and clinical data were retrospectively analyzed in 72 patients. Results Carry on an electroen-cephalogram record under the awake state, normal 54, abnormal 18 (including 8 cases of untypical focal discharge). Under sleep condition the epileptiform discharge all appears in the controtemporal area can be found in the EEG records of 54 ca-ses of normal EEG under the awake state. Conclusions The EEG can greatly increase the diagnosis rate in benign child-hood epilepsy with centrotemporal spike diagnosis. EEG is an important diagnostic basis for this disease. It may help the di-agnosis to know the EEG and clinical characteristics of BECT.%目的 分析脑电图(EEG)在伴中央颞部棘波的良性儿童癫痫(BECCT)的诊断意义.方法 对72例BECCT的EEG及临床资料进行回顾性分析.结果 清醒时,EEG正常54例,异常18例(含8例不典型局灶性放电),对清醒时EEG正常54例均进行睡眠EEG描记,则均于中央颞部出现棘、尖渡.结论 睡眠EEG大大提高了BECCT的诊断率,EEG为诊断BECCT的根本依据.认识BECCT的EEG及临床特点,有利于BECCT的诊断及预后评估.

  6. Analysis of Breast Thermography Using Fractal Dimension to Establish Possible Difference between Malignant and Benign Patterns

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    Mahnaz Etehad Tavakol

    2010-01-01

    Full Text Available Early detection of breast cancer by means of thermal imaging has a long and extremely controversial history. Recently, the availability of highly sensitive infrared (IR cameras which can produce high-resolution diagnostic images of the temperature and vascular changes of breasts, as well as a better knowledge of advanced image processing techniques, has generated a renewed interest. The objective of this study is to investigate fractal analysis of breast thermal images and to develop an algorithm for detecting benignity and malignancy of breast diseases. The study is based on IR images captured by thermal camera, in which the resolution of the results is within the state of the art of IR camera. A total of 7 malignant cases and 8 benign cases have been considered. The breast images were first segmented by fuzzy c-means clustering. Then the first hottest regions for each image were identified and the fractal dimension of those regions was computed. It is shown that the fractal dimension results significantly differ between malignant and benign patterns, suggesting that fractal analysis may potentially improve the reliability of thermography in breast tumor detection.

  7. EXTREME DELTA BRUSH EEG PATTERN IN A CASE WITH ANTI-NMDA RECEPTOR ENCEPHALITIS.

    Science.gov (United States)

    Söylemez, Elif; Güveli, Betül Tekin; Atakli, Dilek; Yatmazoğlu, Merve; Atay, Turan; Dayan, Cengiz

    2015-09-30

    Anti-N-methyl-D-aspartate receptor NMDA-R encephalitis is caused by antibodies against the NMDA-R and characterized by a severe encephalopathy with psychosis, epileptic seizures and autonomic disturbances. This disorder is often accompanied with malignancies, especially ovarian teratoma. Some patients' EEGs show a different pattern similar to the waveforms of premature infants and this pattern is specifically named as extreme delta brush (EDB). We report a 24-year-old female having anti-NMDA receptor encephalitis and EDB patern.

  8. A novel pattern mining approach for identifying cognitive activity in EEG based functional brain networks.

    Science.gov (United States)

    Thilaga, M; Vijayalakshmi, R; Nadarajan, R; Nandagopal, D

    2016-06-01

    The complex nature of neuronal interactions of the human brain has posed many challenges to the research community. To explore the underlying mechanisms of neuronal activity of cohesive brain regions during different cognitive activities, many innovative mathematical and computational models are required. This paper presents a novel Common Functional Pattern Mining approach to demonstrate the similar patterns of interactions due to common behavior of certain brain regions. The electrode sites of EEG-based functional brain network are modeled as a set of transactions and node-based complex network measures as itemsets. These itemsets are transformed into a graph data structure called Functional Pattern Graph. By mining this Functional Pattern Graph, the common functional patterns due to specific brain functioning can be identified. The empirical analyses show the efficiency of the proposed approach in identifying the extent to which the electrode sites (transactions) are similar during various cognitive load states.

  9. Standardized EEG interpretation accurately predicts prognosis after cardiac arrest

    DEFF Research Database (Denmark)

    Westhall, Erik; Rossetti, Andrea O; van Rootselaar, Anne-Fleur

    2016-01-01

    OBJECTIVE: To identify reliable predictors of outcome in comatose patients after cardiac arrest using a single routine EEG and standardized interpretation according to the terminology proposed by the American Clinical Neurophysiology Society. METHODS: In this cohort study, 4 EEG specialists......, blinded to outcome, evaluated prospectively recorded EEGs in the Target Temperature Management trial (TTM trial) that randomized patients to 33°C vs 36°C. Routine EEG was performed in patients still comatose after rewarming. EEGs were classified into highly malignant (suppression, suppression...... with periodic discharges, burst-suppression), malignant (periodic or rhythmic patterns, pathological or nonreactive background), and benign EEG (absence of malignant features). Poor outcome was defined as best Cerebral Performance Category score 3-5 until 180 days. RESULTS: Eight TTM sites randomized 202...

  10. Peak and averaged bicoherence for different EEG patterns during general anaesthesia

    Directory of Open Access Journals (Sweden)

    Myles Paul

    2010-11-01

    levels (comparable BIS estimates were 0.928(0.905-0.950 and 0.801(0.786-0.816. Estimates of linear regression and areas under ROC curves supported Pk findings. Bicoherence for eye movement artifacts were the most distinctive with respect to other EEG patterns (average |z| value 13.233. Conclusions This study quantified associations between deepening anaesthesia and increase in bicoherence for different frequency components and bicoherence estimates. Increase in bicoherence was also established for eye movement artifacts. While identified associations extend earlier findings of bicoherence changes with increases in anaesthetic drug concentration, results indicate that the unequal band bifrequency region, δ_θ, provides better predictive capabilities than equal band bifrequency regions.

  11. Lateralization patterns of covert but not overt movements change with age: An EEG neurofeedback study.

    Science.gov (United States)

    Zich, Catharina; Debener, Stefan; De Vos, Maarten; Frerichs, Stella; Maurer, Stefanie; Kranczioch, Cornelia

    2015-08-01

    The mental practice of movements has been suggested as a promising add-on therapy to facilitate motor recovery after stroke. In the case of mentally practised movements, electroencephalogram (EEG) can be utilized to provide feedback about an otherwise covert act. The main target group for such an intervention are elderly patients, though research so far is largely focused on young populations (neurofeedback framework. CM-induced event-related desynchronization (ERD) was studied in young (mean age: 23.6 years) and elderly (mean age: 62.7 years) healthy adults. Participants performed covert and overt hand movements. CMs were based on kinesthetic motor imagery (MI) or quasi-movements (QM). Based on previous studies investigating QM in the mu frequency range (8-13Hz) QM were expected to result in more lateralized ERD% patterns and accordingly higher classification accuracies. Independent of CM strategy the elderly were characterized by a significantly reduced lateralization of ERD%, due to stronger ipsilateral ERD%, and in consequence, reduced classification accuracies. QM were generally perceived as more vivid, but no differences were evident between MI and QM in ERD% or classification accuracies. EEG feedback enhanced task-related activity independently of strategy and age. ERD% measures of overt and covert movements were strongly related in young adults, whereas in the elderly ERD% lateralization is dissociated. In summary, we did not find evidence in support of more pronounced ERD% lateralization patterns in QM. Our finding of a less lateralized activation pattern in the elderly is in accordance to previous research and with the idea that compensatory processes help to overcome neurodegenerative changes related to normal ageing. Importantly, it indicates that EEG neurofeedback studies should place more emphasis on the age of the potential end-users.

  12. Cortical Sensitivity to Guitar Note Patterns: EEG Entrainment to Repetition and Key

    Science.gov (United States)

    Bridwell, David A.; Leslie, Emily; McCoy, Dakarai Q.; Plis, Sergey M.; Calhoun, Vince D.

    2017-01-01

    Music is ubiquitous throughout recent human culture, and many individual's have an innate ability to appreciate and understand music. Our appreciation of music likely emerges from the brain's ability to process a series of repeated complex acoustic patterns. In order to understand these processes further, cortical responses were measured to a series of guitar notes presented with a musical pattern or without a pattern. ERP responses to individual notes were measured using a 24 electrode Bluetooth mobile EEG system (Smarting mBrainTrain) while 13 healthy non-musicians listened to structured (i.e., within musical keys and with repetition) or random sequences of guitar notes for 10 min each. We demonstrate an increased amplitude to the ERP that appears ~200 ms to notes presented within the musical sequence. This amplitude difference between random notes and patterned notes likely reflects individual's cortical sensitivity to guitar note patterns. These amplitudes were compared to ERP responses to a rare note embedded within a stream of frequent notes to determine whether the sensitivity to complex musical structure overlaps with the sensitivity to simple irregularities reflected in traditional auditory oddball experiments. Response amplitudes to the negative peak at ~175 ms are statistically correlated with the mismatch negativity (MMN) response measured to a rare note presented among a series of frequent notes (i.e., in a traditional oddball sequence), but responses to the subsequent positive peak at ~200 do not show a statistical relationship with the P300 response. Thus, the sensitivity to musical structure identified to 4 Hz note patterns appears somewhat distinct from the sensitivity to statistical regularities reflected in the traditional “auditory oddball” sequence. Overall, we suggest that this is a promising approach to examine individual's sensitivity to complex acoustic patterns, which may overlap with higher level cognitive processes, including

  13. Meditation and the EEG

    OpenAIRE

    West, Michael

    1980-01-01

    Previous research on meditation and the EEG is described, and findings relating to EEG patterns during meditation are discussed. Comparisons of meditation with other altered states are reviewed and it is concluded that, on the basis of existing EEG evidence, there is some reason for differentiating between meditation and drowsing. Research on alpha-blocking and habituation of the blocking response during meditation is reviewed, and the effects of meditation on EEG patterns outside of meditati...

  14. Frontal-temporal synchronization of EEG signals quantified by order patterns cross recurrence analysis during propofol anesthesia.

    Science.gov (United States)

    Shalbaf, Reza; Behnam, Hamid; Sleigh, Jamie W; Steyn-Ross, D Alistair; Steyn-Ross, Moira L

    2015-05-01

    Characterizing brain dynamics during anesthesia is a main current challenge in anesthesia study. Several single channel electroencephalogram (EEG)-based commercial monitors like the Bispectral index (BIS) have suggested to examine EEG signal. But, the BIS index has obtained numerous critiques. In this study, we evaluate the concentration-dependent effect of the propofol on long-range frontal-temporal synchronization of EEG signals collected from eight subjects during a controlled induction and recovery design. We used order patterns cross recurrence plot and provide an index named order pattern laminarity (OPL) to assess changes in neuronal synchronization as the mechanism forming the foundation of conscious perception. The prediction probability of 0.9 and 0.84 for OPL and BIS specified that the OPL index correlated more strongly with effect-site propofol concentration. Also, our new index makes faster reaction to transients in EEG recordings based on pharmacokinetic and pharmacodynamic model parameters and demonstrates less variability at the point of loss of consciousness (standard deviation of 0.04 for OPL compared with 0.09 for BIS index). The result show that the OPL index can estimate anesthetic state of patient more efficiently than the BIS index in lightly sedated state with more tolerant of artifacts.

  15. Human physiological benefits of viewing nature: EEG responses to exact and statistical fractal patterns.

    Science.gov (United States)

    Hagerhall, C M; Laike, T; Küller, M; Marcheschi, E; Boydston, C; Taylor, R P

    2015-01-01

    Psychological and physiological benefits of viewing nature have been extensively studied for some time. More recently it has been suggested that some of these positive effects can be explained by nature's fractal properties. Virtually all studies on human responses to fractals have used stimuli that represent the specific form of fractal geometry found in nature, i.e. statistical fractals, as opposed to fractal patterns which repeat exactly at different scales. This raises the question of whether human responses like preference and relaxation are being driven by fractal geometry in general or by the specific form of fractal geometry found in nature. In this study we consider both types of fractals (statistical and exact) and morph one type into the other. Based on the Koch curve, nine visual stimuli were produced in which curves of three different fractal dimensions evolve gradually from an exact to a statistical fractal. The patterns were shown for one minute each to thirty-five subjects while qEEG was continuously recorded. The results showed that the responses to statistical and exact fractals differ, and that the natural form of the fractal is important for inducing alpha responses, an indicator of a wakefully relaxed state and internalized attention.

  16. Clinical and ictal EEG features in benign infantile epilepsy%良性婴儿癫痫的临床及发作期脑电图特征

    Institute of Scientific and Technical Information of China (English)

    马秀伟; 侯豫; 辜蕊洁; 何芳; 王三梅; 封志纯

    2013-01-01

    Objective To further clarify clinical features and ictal electroencephalographic findings of patients with benign infantile epilepsy(BIE) in order to early recognize and evaluate prognosis. Methods The clinical information, video electroencephalogram(VEEG) characteristics, treatment and prognosis of 21 patients fulfilled the definition of BIE were collected and analyzed. Results The onset age of seizures was from 3 months to 11 months in 21 cases. Clusters of seizures occurred in 19 patients. The seizures were characterized by motion arrest, decreased responsiveness, cyanosis, staring or mild convulsive movements, such as eye deviation, head rotation, clonic movements, or increased limb tone. Interictal EEGs were normal in all patients. Ictal discharges at the onset of a seizure were focal in all seizures. The site of the origin of seizures was in the temporal area in 12 of 19 seizures, whereas it was in the occipital area in 5 seizures and parietal region in 2 seizures. The duration of a seizure on EEG was 55 to 126 seconds. All patients were treated with antiepileptic drugs(11 with levetiracetam, nine with depakine syrup, and 1 with oxcarbazepine). Seizures disappeared within one month in 17 patients. Antiepileptic treatment was withdrawn after 1 year and none of them experienced recurrence of seizures. All patients showed normal psychomotor development at the end of follow up. Conclusions Clusters of seizures often occur in BIE patients. The most frequent site of the seizure origin is in the temporal lobe. The prognosis of BIE is excellent, and excessive treatment should be avoided in such patients.%目的:进一步阐述良性婴儿癫痫(BIE)的临床发作及发作期脑电图(EEG)特征,以便早期识别此病,合理治疗及评估预后。方法对21例符合BIE诊断标准的患儿临床发作及视频脑电图(VEEG)进行分析,并对治疗及预后进行随访。结果患儿发病年龄3~11个月。19例发作初期有丛集性特

  17. Recognition of wake-sleep stage 1 multichannel eeg patterns using spectral entropy features for drowsiness detection.

    Science.gov (United States)

    Sriraam, N; Padma Shri, T K; Maheshwari, Uma

    2016-09-01

    Electroencephalographic (EEG) activity recorded during the entire sleep cycle reflects various complex processes associated with brain and exhibits a high degree of irregularity through various stages of sleep. The identification of transition from wakefulness to stage1 sleep is a challenging area of research for the biomedical community. In this paper, spectral entropy (SE) is used as a complexity measure to quantify irregularities in awake and stage1 sleep of 8-channel sleep EEG data from the polysomnographic recordings of ten healthy subjects. The SE measures of awake and stage1 sleep EEG data are estimated for each second and applied to a multilayer perceptron feed forward neural network (MLP-FF). The network is trained using back propagation algorithm for recognizing these two patterns. Initially, the MLP network is trained and tested for randomly chosen subject-wise combined datasets I and II and then for the combined large dataset III. In all cases, 60 % of the entire dataset is used for training while 20 % is used for testing and 20 % for validation. Results indicate that the MLP neural network learns with maximum testing accuracy of 95.9 % for dataset II. In the case of combined large dataset, the network performs with a maximum accuracy of 99.2 % with 100 hidden neurons. Results show that in channels O1, O2, F3 and F4 (A1, A2 as reference), the mean of the spectral entropy value is higher in awake state than in stage1 sleep indicating that the EEG becomes more regular and rhythmic as the subject attains stage1 sleep from wakefulness. However, in C3 and C4 the mean values of SE values are not very much discriminative of both groups. This may prove to be a very effective indicator for scoring the first two stages of sleep EEG and may be used to detect the transition from wakefulness to stage1 sleep.

  18. Automatic Sleep Stages Classification Using EEG Entropy Features and Unsupervised Pattern Analysis Techniques

    Directory of Open Access Journals (Sweden)

    Jose Luis Rodríguez-Sotelo

    2014-12-01

    Full Text Available Sleep is a growing area of research interest in medicine and neuroscience. Actually, one major concern is to find a correlation between several physiologic variables and sleep stages. There is a scientific agreement on the characteristics of the five stages of human sleep, based on EEG analysis. Nevertheless, manual stage classification is still the most widely used approach. This work proposes a new automatic sleep classification method based on unsupervised feature classification algorithms recently developed, and on EEG entropy measures. This scheme extracts entropy metrics from EEG records to obtain a feature vector. Then, these features are optimized in terms of relevance using the Q-α algorithm. Finally, the resulting set of features is entered into a clustering procedure to obtain a final segmentation of the sleep stages. The proposed method reached up to an average of 80% correctly classified stages for each patient separately while keeping the computational cost low.

  19. Wicket spikes: a case-control study of a benign eletroencephalografic variant pattern "Wicket spikes": estudo de variante eletrográfica benigna

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    MARCUS SABRY AZAR BATISTA

    1999-09-01

    Full Text Available Wicket spikes (WS are a benign eletroencephalogram (EEG variant, seen mainly in adults, during somnolence, in the temporal regions, in many clinical situations. WS can appear in trains or isolatedly, sometimes being difficult to differentiate from epileptiform activity. We reviewed 2,000 EEG's, found 65 with WS (3.25% and compared them with 65 normal EEG without WS. There was statistically significant (SS association between WS and age over 33; adolescent age was correlated to absence of WS and age over 65, to the presence of WS; there was an inverse correlation between WS and epilepsy, related to differences in age; a SS association with cerebrovascular disorders disappeared after controlling for age; a SS correlation with headache was also related to age; female predominance was not SS. There was a great variety of clinical situation associated with WS. We conclude that WS are a inespecific normal variant of the EEG that is age-related.As Wicket spikes (WS são um padrão benigno, variante da normalidade do eletrencefalograma (EEG, vistas principalmente em adultos, durante a sonolência, nas regiões temporais, em situações clínicas variadas. WS aparecem em "trens" ou isoladamente, podendo ser difícil diferenciá-las de atividade epileptiforme. Nós revisamos 2.000 EEG e encontramos 65 com WS (3,25% e os comparamos a 65 EEG 's normais sem WS. Encontramos associação estatisticamente significante (ES entre WS e idade acima de 33 anos; adolescência e ausência de WS e idade acima de 65 e presença de WS. Houve correlação inversa entre WS e epilepsia, explicada por diferenças nas médias de idade. A correlação ES entre WS e doença cerebrovascular desapareceu após controlarmos a idade. A correlação ES a cefaléia dependeu de sua relação à idade. A predominância do sexo feminino não foi ES. Houve maior variedade de situações clínicas associadas a WS. WS são uma variante normal do EEG, idade-relacionada.

  20. Study on patterns and prevalence of EEG abnormalities in children presenting with behavioural disturbances in psychiatry OPD, Gauhati Medical College and Hospital

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    Bobby Hmar

    2016-01-01

    Full Text Available Background of the study: Children with behavioural abnormalities and developmental disorders are often advised electroencephalography (EEG for evaluation of electrophysiological process of the brain to rule out any organic pathology. Various studies have reported abnormal EEG in these groups of children without history of clinical seizure on routine EEG and sleep EEG. Aim of the study: To study pattern and prevalence of EEG abnormalities in children with behavioural abnormalities without history of clinical seizure. Materials and methods: The study is a retrospective study. Ethical clearance has been obtained from institutional ethical committee for the study. To collect data, socio-demographic and clinical data proforma has been used. Data has been evaluated during the period from June 2011 to June 2014 as per selection criteria from the case history record of children with behavioural abnormalities attending child guidance clinic (CGC. Associations of abnormal EEG with various psychiatric diagnoses has been analysed and chi-square test has been used. p value <0.05 has been taken as test of significance. Result: Total 2011 children attended CGC from 2011 June to 2014 June. One hundred and ninety two children of various psychiatric diagnoses as per the tenth revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10 criteria had fulfilled the selection criteria and 113 children had done EEG. Abnormal EEG was found in 26.54% of children with various psychiatric diagnoses. Association was statistically significant (p<0.05. The EEG abnormalities were found more in male gender than female (p<0.05 and more in younger age group (four to ten years, p<0.05. Conclusion: Children with various psychiatric diagnoses have significant association with abnormal EEG without history of clinical seizure.

  1. Error-related EEG patterns during tactile human-machine interaction

    NARCIS (Netherlands)

    Lehne, M.; Ihme, K.; Brouwer, A.M.; Erp, J.B.F. van; Zander, T.O.

    2009-01-01

    Recently, the use of brain-computer interfaces (BCIs) has been extended from active control to passive detection of cognitive user states. These passive BCI systems can be especially useful for automatic error detection in human-machine systems by recording EEG potentials related to human error proc

  2. Small-world Characteristics of EEG Patterns in Post-Anoxic Encephalopathy

    Directory of Open Access Journals (Sweden)

    Martijn eBeudel

    2014-06-01

    Full Text Available Post-Anoxic Encephalopathy (PAE has a heterogenous outcome which is difficult to predict. At present, it is possible to predict poor outcome using somatosensory evoked potentials (SSEP in only a minority of the patients at an early stage. In addition, it remains difficult to predict good outcome at an early stage. Network architecture, as can be quantified with continuous electroencephalography (cEEG, may serve as a candidate measure for predicting neurological outcome. Here we explore whether cEEG monitoring can be used to detect the integrity of neural network architecture in patients with PAE after cardiac arrest. From 56 patients with PAE treated with mild therapeutic hypothermia (MTH, 19-channel cEEG data was recorded starting as soon as possible after cardiac arrest. Adjacency matrices of shared frequencies between 1 and 25 Hz of the EEG channels were obtained using Fourier transformations. Number of network nodes and connections, clustering coefficient (C, average path length (L and small-world index (SWI were derived. Outcome was quantified by the best Cerebral Performance Category (CPC-score within 6 months. Compared to non-survivors, survivors showed significantly more nodes and connections. L was significantly higher and C and SWI were significantly lower in the survivor group than in the non-survivor group. The number of nodes, connections and the L negatively correlated with the CPC-score. C and SWI correlated positively with the CPC-score. The combination of number of nodes, connections, C and L showed the most significant difference and correlation between survivors and non-survivors and CPC-score. Our data might implicate that non-survivors have insufficient distribution and differentiation of neural activity for regaining normal brain function. These network differences, already present during hypothermia, might be further developed as early prognostic markers. The predictive values are however still inferior to current practice

  3. Single Trial EEG Patterns for the Prediction of Individual Differences in Fluid Intelligence

    Science.gov (United States)

    Qazi, Emad-ul-Haq; Hussain, Muhammad; Aboalsamh, Hatim; Malik, Aamir Saeed; Amin, Hafeez Ullah; Bamatraf, Saeed

    2017-01-01

    Assessing a person's intelligence level is required in many situations, such as career counseling and clinical applications. EEG evoked potentials in oddball task and fluid intelligence score are correlated because both reflect the cognitive processing and attention. A system for prediction of an individual's fluid intelligence level using single trial Electroencephalography (EEG) signals has been proposed. For this purpose, we employed 2D and 3D contents and 34 subjects each for 2D and 3D, which were divided into low-ability (LA) and high-ability (HA) groups using Raven's Advanced Progressive Matrices (RAPM) test. Using visual oddball cognitive task, neural activity of each group was measured and analyzed over three midline electrodes (Fz, Cz, and Pz). To predict whether an individual belongs to LA or HA group, features were extracted using wavelet decomposition of EEG signals recorded in visual oddball task and support vector machine (SVM) was used as a classifier. Two different types of Haar wavelet transform based features have been extracted from the band (0.3 to 30 Hz) of EEG signals. Statistical wavelet features and wavelet coefficient features from the frequency bands 0.0–1.875 Hz (delta low) and 1.875–3.75 Hz (delta high), resulted in the 100 and 98% prediction accuracies, respectively, both for 2D and 3D contents. The analysis of these frequency bands showed clear difference between LA and HA groups. Further, discriminative values of the features have been validated using statistical significance tests and inter-class and intra-class variation analysis. Also, statistical test showed that there was no effect of 2D and 3D content on the assessment of fluid intelligence level. Comparisons with state-of-the-art techniques showed the superiority of the proposed system. PMID:28163676

  4. Discrimination of Motor Imagery-Induced EEG Patterns in Patients with Complete Spinal Cord Injury

    Directory of Open Access Journals (Sweden)

    G. Pfurtscheller

    2009-01-01

    Full Text Available EEG-based discrimination between different motor imagery states has been subject of a number of studies in healthy subjects. We investigated the EEG of 15 patients with complete spinal cord injury during imagined right hand, left hand, and feet movements. In detail we studied pair-wise discrimination functions between the 3 types of motor imagery. The following classification accuracies (mean ± SD were obtained: left versus right hand 65.03% ± 8.52, left hand versus feet 68.19% ± 11.08, and right hand versus feet 65.05% ± 9.25. In 5 out of 8 paralegic patients, the discrimination accuracy was greater than 70% but in only 1 out of 7 tetraplagic patients. The present findings provide evidence that in the majority of paraplegic patients an EEG-based BCI could achieve satisfied results. In tetraplegic patients, however, it is expected that extensive training-sessions are necessary to achieve a good BCI performance at least in some subjects.

  5. EEG biofeedback

    OpenAIRE

    Dvořáček, Michael

    2010-01-01

    Vznik EEG aktivity v mozku, rozdělení EEG vln podle frekvence, způsob měření EEG, přístroje pro měření EEG. Dále popis biofeedback metody, její možnosti a návrh biofeedback her. Popis zpracování naměřených EEG signálů. EEG generation, brain rhythms, methods of recording EEG, EEG recorder. Description of biofeedback, potentialities of biofeedback, proposal of biofeedback games. Description of processing measured EEG signals. B

  6. EEG in the neonatal unit.

    Science.gov (United States)

    Lamblin, M D; de Villepin-Touzery, A

    2015-03-01

    The execution and interpretation of neonatal EEG adheres to strict and specific criteria related to this very early age. In preterm newborns, the dedicated healthcare staff needs to respect EEG indications and chronology of EEG recordings in order to diagnose and manage various pathologies, and use EEG in addition to cerebral imaging. EEG analysis focuses on a global vision of the recording according to the neonate's state of alertness and various age-related patterns. Monitoring of continuous conventional EEG and simplified EEG signal processing can help screen for seizures and monitor the effect of antiepileptic treatment, as well as appreciating changes in EEG background activity, for diagnostic and prognostic purposes. EEG reports should be highly explanatory to meet the expectations of the physician's clinical request.

  7. Similar or disparate brain patterns? The intra-personal EEG variability of three women with multiple personality disorder.

    Science.gov (United States)

    Lapointe, A R; Crayton, J W; DeVito, R; Fichtner, C G; Konopka, L M

    2006-07-01

    Quantitative EEG was used to assess the intra-personal variability of brain electrical activity for 3 women diagnosed with Multiple Personality Disorder (MPD). Two separate control groups (within-subject and between-subject) were used to test the hypothesis that the intra-personal EEG variability between 2 alters would be less than the interpersonal EEG variability between 2 controls, and similar to the intra-personal EEG variability of a single personality. This hypothesis was partially supported. In general, the 2 EEG records of a MPD subject (alter 1 vs. alter 2) were more different from one another than the 2 EEG records of a single control, but less different from one another than the EEG records of 2 separate controls. Most of the EEG variability between alters involved beta activity in the frontal and temporal lobes.

  8. Pattern of mental ill health morbidities following hysterectomy for benign gynaecological disorders among Nigerian women

    Directory of Open Access Journals (Sweden)

    Morhason-Bello Imran O

    2009-07-01

    Full Text Available Abstract Objective to compare the pre and post hysterectomy mental ill health (MIH status and also, to determine whether there is any association with the surgical indication. Methodology An observational study, conducted among women scheduled for hysterectomy at the University College Hospital, Ibadan from January till June 2005. The MIH morbidities were assessed using a validated general health questionnaire (GHQ before and after the surgery by trained research assistant. The score of 4 and above was used as the cut off. Cross tabulations were performed to detect any association and also to compare pre and post hysterectomy mental health status. The level of statistical significance was set at P Results Of the 50 women recruited, 45 participated in the study. The age range of the participants was 35 to 63 years with a mean of 48.6 (SD = 0.6 years. Anxiety related disorder was present in 20 (44.4%, and depression in 3 (6.7% before hysterectomy. Post surgery, there was significant increase in those with anxiety by 6.8% and a reduction in the proportion of depressive illness by 2.3%. Uterine fibroid as a preoperative diagnosis, had significant association among those with anxiety related disorder (68.4% and depression (10.5%. Conclusion This study suggests that mental ill health may complicates hysterectomy for benign uterine pathology among Nigerian women, and that anxiety related disorders increases after operation with the highest proportion in those with clinical diagnosis of Uterine Fibroid. We recommend adequate preoperative counseling using properly trained psychologists when affordable to minimize these morbidities.

  9. A stable pattern of EEG spectral coherence distinguishes children with autism from neuro-typical controls - a large case control study

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    Duffy Frank H

    2012-06-01

    Full Text Available Abstract Background The autism rate has recently increased to 1 in 100 children. Genetic studies demonstrate poorly understood complexity. Environmental factors apparently also play a role. Magnetic resonance imaging (MRI studies demonstrate increased brain sizes and altered connectivity. Electroencephalogram (EEG coherence studies confirm connectivity changes. However, genetic-, MRI- and/or EEG-based diagnostic tests are not yet available. The varied study results likely reflect methodological and population differences, small samples and, for EEG, lack of attention to group-specific artifact. Methods Of the 1,304 subjects who participated in this study, with ages ranging from 1 to 18 years old and assessed with comparable EEG studies, 463 children were diagnosed with autism spectrum disorder (ASD; 571 children were neuro-typical controls (C. After artifact management, principal components analysis (PCA identified EEG spectral coherence factors with corresponding loading patterns. The 2- to 12-year-old subsample consisted of 430 ASD- and 554 C-group subjects (n = 984. Discriminant function analysis (DFA determined the spectral coherence factors' discrimination success for the two groups. Loading patterns on the DFA-selected coherence factors described ASD-specific coherence differences when compared to controls. Results Total sample PCA of coherence data identified 40 factors which explained 50.8% of the total population variance. For the 2- to 12-year-olds, the 40 factors showed highly significant group differences (P Conclusions Classification success suggests a stable coherence loading pattern that differentiates ASD- from C-group subjects. This might constitute an EEG coherence-based phenotype of childhood autism. The predominantly reduced short-distance coherences may indicate poor local network function. The increased long-distance coherences may represent compensatory processes or reduced neural pruning. The wide average spectral range

  10. Spectral feature extraction of EEG signals and pattern recognition during mental tasks of 2-D cursor movements for BCI using SVM and ANN.

    Science.gov (United States)

    Bascil, M Serdar; Tesneli, Ahmet Y; Temurtas, Feyzullah

    2016-09-01

    Brain computer interface (BCI) is a new communication way between man and machine. It identifies mental task patterns stored in electroencephalogram (EEG). So, it extracts brain electrical activities recorded by EEG and transforms them machine control commands. The main goal of BCI is to make available assistive environmental devices for paralyzed people such as computers and makes their life easier. This study deals with feature extraction and mental task pattern recognition on 2-D cursor control from EEG as offline analysis approach. The hemispherical power density changes are computed and compared on alpha-beta frequency bands with only mental imagination of cursor movements. First of all, power spectral density (PSD) features of EEG signals are extracted and high dimensional data reduced by principle component analysis (PCA) and independent component analysis (ICA) which are statistical algorithms. In the last stage, all features are classified with two types of support vector machine (SVM) which are linear and least squares (LS-SVM) and three different artificial neural network (ANN) structures which are learning vector quantization (LVQ), multilayer neural network (MLNN) and probabilistic neural network (PNN) and mental task patterns are successfully identified via k-fold cross validation technique.

  11. Patterns of Benign and Malignant Lesions of the Thyroid in Two Wilayahs of Northeastern Algeria

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    Mona Guidoum

    2015-01-01

    Full Text Available The aim of this study is to compare histological patterns and to estimate the burden of thyroid cancers in the two Wilayahs (departments of El-Taref and Guelma in northeast of Algeria (total population 0.9 million, locally reputed as having different rates of endemic thyroid diseases and cancer. A retrospective analysis of central pathology registers and clinical records of patients with thyroid diseases, covering the period 2008–2012, was conducted. A total of 145 cases of thyroid cancers with histological confirmation were registered in the two Wilayahs during the period, with a female to male ratio of 5.9 : 1. Estimates of crude incidence rates suggested that thyroid cancers were twice as frequent in the Wilayah of Guelma compared to El-Taref (p<0.05 with a tendency to occur at a younger age in resident of the Wilayah of El-Taref. Diagnoses of thyroid adenoma were more frequent in the Wilayah of Guelma, whereas the prevalence of other thyroid lesions, including goitre, was similar in the two Wilayahs. This first descriptive study on geographic variations in thyroid cancer in Northern Africa suggests that significant differences may occur in relation with environmental and lifestyle exposures.

  12. Implementation and analysis of relief patterns of the surface of benign and malignant lesions of the skin by microtopography

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Pacheco, Maria del Carmen Lopez [Laboratorio de CitopatologIa Ambiental, Departamento de MorfologIa, ENCB-IPN, UP Lazaro Cardenas, Casco de Santo Tomas, 11340 (Mexico); Martins-Costa, Manuel Filipe Pereira da Cunha [Departamento de Fisica, Universidad do Minho, Escola de Ciencias Campus de Gualtar-PT-4710-057 Braga (Portugal); Zapata, Aura Judith Perez [Laboratorio de CitopatologIa Ambiental, Departamento de MorfologIa, ENCB-IPN, UP Lazaro Cardenas, Casco de Santo Tomas, 11340 (Mexico); Cherit, Judith DomInguez [Departamento de DermatologIa, Hospital General Dr Manuel Gea Gonzalez, Calzada de Tlalpan No 4800, 14000 (Mexico); Gallegos, Eva Ramon [Laboratorio de CitopatologIa Ambiental, Departamento de MorfologIa, ENCB-IPN, UP Lazaro Cardenas, Casco de Santo Tomas, 11340 (Mexico)

    2005-12-07

    The objective of this study was to be able to distinguish between healthy skin tissue and malignant ones, furthermore determining a unique pattern of roughness for each skin lesion by microtopographic analysis of the skin surface of Mexican patients during the period from April to October 2002. The standard technique used in this study for the diagnosis of skin cancer and the comparison of the results was the haematoxylin-eosin histopathological technique. Latex impressions were taken from skin lesions as well as from the healthy skin of each patient to serve as control samples. These impressions were analysed by the MICROTOP.03.MFC microtopographic system inspection. It was observed that when the tumour becomes rougher, more malign will be the lesion. On average, the melanoma present an increase of roughness of 67% compared to healthy skin, obtaining a roughness relation of 1:2.54. The percentage decreases to 49% (49%, 1:60) in the case of basal cell carcinoma and to 40% in pre-malignant lesions such as melanocytic nevus (40%, 1:150). In benign lesions such as the seborrhoea keratosis only a small increase in roughness was noted (4%, 1:0.72). Microtopographic inspection of the skin surface can be considered as a complementary diagnostic technique for skin cancer.

  13. EEG Pattern Recognition to Diagnose Epilepsy Using Wavelet and Chaos Transformations

    Directory of Open Access Journals (Sweden)

    MohammadReza Yazdchi

    2008-03-01

    Full Text Available By the time-frequency transformations like wavelet and chaos theory to find the feature from sub-bands, it is possible to diagnose the epilepsy although there are some noises and signals. To decompose the EEG into sub-bands such as delta, theta, alpha, beta and gamma, wavelet analysis is used. Chaos theory is used to compute standard deviation, correlation dimension and Lyapunov exponent from the sub-bands, then the neuron system and other classifiers, standard deviations and averages are used to increase the diagnosis accuracy of epilepsy for all three groups of normal, ictal, and inter ictal.Results show a fuzzy subtractive clustering in a specific distance including 8 parameters (persistence 96.8% and standard deviation 0.7 and by Ensemble averaging including 6 parameters (persistence 97.5% and standard deviation 0 is better than other methods and proper for clustering epilepsy disease.This statistics is considerable while visual consideration by specialized neurologists isn’t more than 80 percent.

  14. Support vector machines to detect physiological patterns for EEG and EMG-based human-computer interaction: a review

    Science.gov (United States)

    Quitadamo, L. R.; Cavrini, F.; Sbernini, L.; Riillo, F.; Bianchi, L.; Seri, S.; Saggio, G.

    2017-02-01

    Support vector machines (SVMs) are widely used classifiers for detecting physiological patterns in human-computer interaction (HCI). Their success is due to their versatility, robustness and large availability of free dedicated toolboxes. Frequently in the literature, insufficient details about the SVM implementation and/or parameters selection are reported, making it impossible to reproduce study analysis and results. In order to perform an optimized classification and report a proper description of the results, it is necessary to have a comprehensive critical overview of the applications of SVM. The aim of this paper is to provide a review of the usage of SVM in the determination of brain and muscle patterns for HCI, by focusing on electroencephalography (EEG) and electromyography (EMG) techniques. In particular, an overview of the basic principles of SVM theory is outlined, together with a description of several relevant literature implementations. Furthermore, details concerning reviewed papers are listed in tables and statistics of SVM use in the literature are presented. Suitability of SVM for HCI is discussed and critical comparisons with other classifiers are reported.

  15. Schizophrenia patients and 22q11.2 deletion syndrome adolescents at risk express the same deviant patterns of resting state EEG microstates: A candidate endophenotype of schizophrenia

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    Miralena I. Tomescu

    2015-09-01

    Full Text Available Schizophrenia is a complex psychiatric disorder and many of the factors contributing to its pathogenesis are poorly understood. In addition, identifying reliable neurophysiological markers would improve diagnosis and early identification of this disease. The 22q11.2 deletion syndrome (22q11DS is one major risk factor for schizophrenia. Here, we show further evidence that deviant temporal dynamics of EEG microstates are a potential neurophysiological marker by showing that the resting state patterns of 22q11DS are similar to those found in schizophrenia patients. The EEG microstates are recurrent topographic distributions of the ongoing scalp potential fields with temporal stability of around 80 ms that are mapping the fast reconfiguration of resting state networks. Five minutes of high-density EEG recordings was analysed from 27 adult chronic schizophrenia patients, 27 adult controls, 30 adolescents with 22q11DS, and 28 adolescent controls. In both patient groups we found increased class C, but decreased class D presence and high transition probabilities towards the class C microstates. Moreover, these aberrant temporal dynamics in the two patient groups were also expressed by perturbations of the long-range dependency of the EEG microstates. These findings point to a deficient function of the salience and attention resting state networks in schizophrenia and 22q11DS as class C and class D microstates were previously associated with these networks, respectively. These findings elucidate similarities between individuals at risk and schizophrenia patients and support the notion that abnormal temporal patterns of EEG microstates might constitute a marker for developing schizophrenia.

  16. Mental EEG Analysis Based on Infomax Algorithm

    Institute of Scientific and Technical Information of China (English)

    WUXiao-pei; GuoXiao-jing; ZANGDao-xin; SHENQian

    2004-01-01

    The patterns of EEG will change with mental tasks performed by the subject. In the field of EEG signal analysis and application, the study to get the patterns of mental EEG and then to use them to classify mental tasks has the significant scientific meaning and great application value. But for the reasons of different artifacts existing in EEG, the pattern detection of EEG under normal mental states is a very difficult problem. In this paper, Independent Component Analysisis applied to EEG signals collected from performing different mental tasks. The experiment results show that when one subject performs a single mental task in different trials, the independent components of EEG are very similar. It means that the independent components can be used as the mental EEG patterns to classify the different mental tasks.

  17. EEG oscillatory patterns are associated with error prediction during music performance and are altered in musician's dystonia.

    Science.gov (United States)

    Ruiz, María Herrojo; Strübing, Felix; Jabusch, Hans-Christian; Altenmüller, Eckart

    2011-04-15

    Skilled performance requires the ability to monitor ongoing behavior, detect errors in advance and modify the performance accordingly. The acquisition of fast predictive mechanisms might be possible due to the extensive training characterizing expertise performance. Recent EEG studies on piano performance reported a negative event-related potential (ERP) triggered in the ACC 70 ms before performance errors (pitch errors due to incorrect keypress). This ERP component, termed pre-error related negativity (pre-ERN), was assumed to reflect processes of error detection in advance. However, some questions remained to be addressed: (i) Does the electrophysiological marker prior to errors reflect an error signal itself or is it related instead to the implementation of control mechanisms? (ii) Does the posterior frontomedial cortex (pFMC, including ACC) interact with other brain regions to implement control adjustments following motor prediction of an upcoming error? (iii) Can we gain insight into the electrophysiological correlates of error prediction and control by assessing the local neuronal synchronization and phase interaction among neuronal populations? (iv) Finally, are error detection and control mechanisms defective in pianists with musician's dystonia (MD), a focal task-specific dystonia resulting from dysfunction of the basal ganglia-thalamic-frontal circuits? Consequently, we investigated the EEG oscillatory and phase synchronization correlates of error detection and control during piano performances in healthy pianists and in a group of pianists with MD. In healthy pianists, the main outcomes were increased pre-error theta and beta band oscillations over the pFMC and 13-15 Hz phase synchronization, between the pFMC and the right lateral prefrontal cortex, which predicted corrective mechanisms. In MD patients, the pattern of phase synchronization appeared in a different frequency band (6-8 Hz) and correlated with the severity of the disorder. The present

  18. Accuracy of EEG reactivity, EEG patterns, and the Glasgow Coma Scale in predicting outcomes of comatose patients with severe head injuries%脑电图反应性预测重型颅脑外伤性昏迷患者预后的研究

    Institute of Scientific and Technical Information of China (English)

    宋春杰; 孙巧英; 杜一星; 张克忠; 万琪; 赵春生

    2013-01-01

    Objective To predict outcomes in comatose patients with severe head injuries (SHI) by comparing EEG reactivity,EEG patterns,and Glasgow Coma Scale (GCS) scores.Methods In 55 patients with comatose subsequent to severe head injury,we measured EEG reactivity,EEG patterns,and GCS scores to compare them with the outcomes after one year using the discriminant analysis method.Results EEG reactivity correctly classified 87.3%,EEG patterns classified 78.2%,and GCS allowed a correct classification in only 74.5%,P < 0.05.Conclusion EEG reactivity is an excellent outcome predictor in comatose patients with SHI and superior to EEG patterns and GCS.%目的 比较脑电图(EEG)反应性、EEG分型和GCS评分三种方法预测重型颅脑外伤性昏迷患者预后的临床价值.方法 入组患者为2007年1月至2010年12月,南京医科大学第一附属医院重型颅脑外伤性昏迷患者55例,分别对其进行了EEG反应性、EEG分型和GCS检查评估,并进行1年的随访,观察患者的预后转归情况.结果 EEG反应性、EEG分型和GCS评分预测昏迷患者预后的准确度分别为87.3%、78.2%和74.5%,P<0.05.结论 EEG反应性是判断颅脑外伤性昏迷患者预后较为理想的预测指标.

  19. The perception of stress pattern in young cochlear implanted children: an EEG study

    Directory of Open Access Journals (Sweden)

    Niki Katerina Vavatzanidis

    2016-03-01

    Full Text Available Children with sensorineural hearing loss may (regain hearing with a cochlear implant – a device that transforms sounds into electric pulses and bypasses the dysfunctioning inner ear by stimulating the auditory nerve directly with an electrode array. Many implanted children master the acquisition of spoken language successfully, yet we still have little knowledge of the actual input they receive with the implant and specifically which language sensitive cues they hear. This would be important however, both for understanding the flexibility of the auditory system when presented with stimuli after a (life-long phase of deprivation and for planning therapeutic intervention. In rhythmic languages the general stress pattern conveys important information about word boundaries. Infant language acquisition relies on such cues and can be severely hampered when this information is missing, as seen for dyslexic children and children with specific language impairment. Here we ask whether children with a cochlear implant perceive differences in stress patterns during their language acquisition phase and if they do, whether it is present directly following implant stimulation or if and how much time is needed for the auditory system to adapt to the new sensory modality. We performed a longitudinal ERP study, testing in bimonthly intervals the stress pattern perception of 17 young hearing impaired children (age range: 9-50 months; mean: 22 months during their first 6 months of implant use. An additional session before the implantation served as control baseline. During a session they passively listened to an oddball paradigm featuring the disyllable baba, which was stressed either on the first or second syllable (trochaic vs. iambic stress pattern. A group of age-matched normal hearing children participated as controls.Our results show, that within the first 6 months of implant use the implanted children develop a negative mismatch response for iambic but not

  20. Perfusion pattern and time of vascularisation with CEUS increase accuracy in differentiating between benign and malignant tumours in 216 musculoskeletal soft tissue masses

    Energy Technology Data Exchange (ETDEWEB)

    De Marchi, Armanda, E-mail: armanda.demarchi@tiscali.it [Department of Imaging, Azienda Ospedaliera Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino (Italy); Prever, Elena Brach del, E-mail: elena.brach@unito.it [Department of OrthopaedicOncology and ReconstructiveSurgery, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino (Italy); Cavallo, Franco, E-mail: franco.cavallo@unito.it [Department of Public health and Paediatrics, University of Turin, Via Santena 5-bis, 10126 Torino (Italy); Pozza, Simona, E-mail: simona.pozza@tin.it [Department of Imaging, Azienda Ospedaliera Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino (Italy); Linari, Alessandra, E-mail: linaralessandra@libero.it [Department of Pathology, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Regina Margherita Hospital, Piazza Polonia, 10126 Torino (Italy); Lombardo, Paolo, E-mail: pao.lombardo82@gmail.com [Department of DiagnosticImaging and Radiotherapy of the University of Turin, Azienda Ospedaliero-Universitaria Città della Salute e della Scienza di Torino, Via Genova 3, 10126 Torino (Italy); Comandone, Alessandro, E-mail: alessandro.comandone@gradenigo.it [Department of Oncology, Gradenigo Hospital, Corso Regina Margherita, 8/10.10153 Torino (Italy); Piana, Raimondo, E-mail: raimondo.piana@libero.it [Department of OrthopaedicOncology and ReconstructiveSurgery, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino (Italy); Faletti, Carlo [Department of Imaging, Azienda Ospedaliera Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino (Italy)

    2015-01-15

    Introduction: Musculoskeletal Soft Tissue Tumours (STT) are frequent heterogeneous lesions. Guidelines consider a mass larger than 5 cm and deep with respect to the deep fascia potentially malignant. Contrast Enhanced Ultrasound (CEUS) can detect both vascularity and tumour neoangiogenesis. We hypothesised that perfusion patterns and vascularisation time could improve the accuracy of CEUS in discriminating malignant tumours from benign lesions. Materials and methods: 216 STT were studied: 40% benign lesions, 60% malignant tumours, 56% in the lower limbs. Seven CEUS perfusion patterns and three types of vascularisation (arterial-venous uptake, absence of uptake) were applied. Accuracy was evaluated by comparing imaging with the histological diagnosis. Univariate and multivariate analysis, Chi-square test and t-test for independent variables were applied; significance was set at p < 0.05 level, 95% computed CI. Results: CEUS pattern 6 (inhomogeneous perfusion), arterial uptake and location in the lower limb were associated with high risk of malignancy. CEUS pattern has PPV 77%, rapidity of vascularisation PPV 69%; location in the limbs is the most sensitive indicator, but NPV 52%, PPV 65%. The combination of CEUS-pattern and vascularisation has 74% PPV, 60% NPV, 70% sensitivity. No correlation with size and location in relation to the deep fascia was found. Conclusion: US with CEUS qualitative analysis could be an accurate technique to identify potentially malignant STT, for which second line imaging and biopsy are indicated in Referral Centers. Intense inhomogeneous enhancement with avascular areas and rapid vascularisation time could be useful in discriminating benign from malignant SST, overall when the lower limbs are involved.

  1. Oscillatory signatures of crossmodal congruence effects: An EEG investigation employing a visuotactile pattern matching paradigm.

    Science.gov (United States)

    Göschl, Florian; Friese, Uwe; Daume, Jonathan; König, Peter; Engel, Andreas K

    2015-08-01

    Coherent percepts emerge from the accurate combination of inputs from the different sensory systems. There is an ongoing debate about the neurophysiological mechanisms of crossmodal interactions in the brain, and it has been proposed that transient synchronization of neurons might be of central importance. Oscillatory activity in lower frequency ranges (pattern matching paradigm and analyzed oscillatory power in the theta- (4-7Hz), alpha- (8-13Hz) and beta-bands (13-30Hz). Employing the same physical stimuli, separate tasks of the experiment either required the detection of predefined targets in visual and tactile modalities or the explicit evaluation of crossmodal stimulus congruence. Analysis of the behavioral data showed benefits for congruent visuotactile stimulus combinations. Differences in oscillatory dynamics related to crossmodal congruence within the two tasks were observed in the beta-band for crossmodal target detection, as well as in the theta-band for congruence evaluation. Contrasting ongoing activity preceding visuotactile stimulation between the two tasks revealed differences in the alpha- and beta-bands. Source reconstruction of between-task differences showed prominent involvement of premotor cortex, supplementary motor area, somatosensory association cortex and the supramarginal gyrus. These areas not only exhibited more involvement in the pre-stimulus interval for target detection compared to congruence evaluation, but were also crucially involved in post-stimulus differences related to crossmodal stimulus congruence within the detection task. These results add to the increasing evidence that low frequency oscillations are functionally relevant for integration in distributed brain networks, as demonstrated for crossmodal interactions in visuotactile pattern matching in the current study.

  2. Specific EEG sleep pattern in the prefrontal cortex in primary insomnia.

    Directory of Open Access Journals (Sweden)

    Joy Perrier

    Full Text Available OBJECTIVE: To assess the specific prefrontal activity in comparison to those in the other main cortical areas in primary insomnia patients and in good sleepers. METHODS: Fourteen primary insomnia patients and 11 good sleepers were included in the analysis. Participants completed one night of polysomnography in the sleep lab. Power spectra were calculated during the NREM (Non-rapid eyes movements and the REM (Rapid eyes movements sleep periods at prefrontal, occipital, temporal and central electrode positions. RESULTS: During the NREM sleep, the power spectra did not differ between groups in the prefrontal cortex; while primary insomnia patients exhibited a higher beta power spectrum and a lower delta power spectrum compared to good sleepers in other areas. During the REM sleep, the beta1 power spectrum was lower in the prefrontal cortex in primary insomnia patients compared to good sleepers; while no significant difference between groups was obtained for the other areas. CONCLUSIONS: The present study shows a specific prefrontal sleep pattern during the whole sleep period. In addition, we suggest that primary insomnia patients displayed a dysfunction in the reactivation of the limbic system during the REM sleep and we give additional arguments in favor of a sleep-protection mechanism displayed by primary insomnia patients.

  3. EEG spectral power in phasic and tonic REM sleep: different patterns in young adults and children.

    Science.gov (United States)

    Simor, Péter; Gombos, Ferenc; Szakadát, Sára; Sándor, Piroska; Bódizs, Róbert

    2016-06-01

    Rapid eye movement sleep is composed of phasic and tonic periods, two distinguishable microstates in terms of arousal thresholds and sensory processing. Background electroencephalogram oscillations are also different between periods with (phasic state) and periods without (tonic state) eye movements. In Study 1, previous findings analysing electroencephalogram spectral power in phasic and tonic rapid eye movement sleep were replicated, and analyses extended to the high gamma range (52-90 Hz). In Study 2, phasic and tonic spectral power differences within a group of 4-8-year-old children were examined. Based on the polysomnographic data of 20 young adults, the phasic state yielded increased delta and theta power in anterior sites, as well as generally decreased high alpha and beta power in comparison to the tonic state. Moreover, phasic periods exhibited greater spectral power in the lower and the higher gamma band. Interestingly, children (n = 18) exhibited a different pattern, showing increased activity in the low alpha range during phasic periods. Moreover, during phasic in contrast to tonic rapid eye movement sleep, increased low and high gamma and enhanced low gamma band power emerged in anterior and posterior regions, respectively. The current findings show that spectral activity within the high gamma range substantially contributes to the differences between phasic and tonic rapid eye movement sleep, especially in adults. Moreover, the current data underscore the heterogeneity of rapid eye movement sleep, and point to marked differences between young adults and children regarding phasic/tonic electroencephalogram spectral power. These results suggest that the differentiation between phasic and tonic rapid eye movement periods undergoes maturation.

  4. Significance of incidental nasopharyngeal uptake on {sup 1}''8F-FDG PET/CT: Patterns of benign/physiologic uptake and differentiation from malignancy

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    Lee, Na Rae; Yoo, Le Ryung; Yoon, Hyuk Jin; Lee, Yeong Joo; Oh, Jin Kyoung [Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2015-03-15

    The purpose of this study was to assess the significance of incidental nasopharyngeal uptake on 18F-FDG PET/CT and to identify image patterns useful in the differentiation between benign or physiologic activity and nasopharyngeal carcinoma. We retrospectively reviewed medical records of patients with nasopharyngeal uptakes on 18F-FDG PET/CT scans taken between January 2010 and July 2011. Patients with head and neck cancer, other metastatic head and neck lesions, or lymphoma were excluded. Total 177 patients were enrolled (Group A). PET images were reviewed for patterns of nasopharyngeal FDG uptake, presence/absence of cervical lymph node uptake and pattern of cervical node uptake. Diagnostic confirmation was made by pathology or clinical and radiological follow-up for 1 year or longer. Furthermore, initial PET/CT images of 48 patients with nasopharyngeal carcinoma (Group B) were reviewed for comparison with PET/CT images of Group A patients. All nasopharyngeal uptakes in Group A were confirmed to be benign. Group B showed significantly more intense FDG uptake (SUV{sub max} of Group A 3.9 ± 1.4 vs. Group B 10.4 ± 4.6, p<0.001). and asymmetric nasopharyngeal uptake (asymmetric uptake of Group A 67.8% vs. Group B 89.6%). When SUV{sub max} of 6.0 was used as cut off for detection of malignant nasopharyngeal uptake, the area under the ROC curve was 0.93 (95% confidence interval, 0.88-0.98), with a sensitivity of 88.1% and a specificity of 91.7%. Metastatic nodes in Group B showed higher SUV{sub max} (Group A 2.3 ± 0.6 vs. Group B 7.1 ± 4.0, p<0.001) and larger size (short axis of Group A 5.3 ± 2.0 mm vs. Group B 13.1 ± 4.7 mm, p<0.001) than benign nodes of Group A. The majority of Group B cases demonstrated retropharyngeal lymph node uptake (70.8%), compared to only 2 cases in Group A. In patients without a history of underlying malignancy involving head and neck, incidental nasopharyngeal uptake on PET/CT does not indicate malignancy. However, if the

  5. Use of personal EEG monitors in a behavioral neuroscience course to investigate natural setting sleep patterns and the factors affecting them in college students.

    Science.gov (United States)

    Marshall, Jillian C; Malerba, Julie R; Schroeder, Joseph A

    2011-01-01

    Sleep is often a topic of avid interest to college students, yet it is one that does not yield itself well to hands-on, interactive learning modules. Supplementing classroom learning with interactive "real world" laboratory activities provides students with a deeper understanding of behavior and its neural control. The project described here was designed to supplement the teaching of EEGs, sleep and circadian rhythms and involved students in the empirical process from hypothesizing about the factors that affect sleep, to personal data collection, data analysis and writing in the style of a peer-reviewed manuscript. Students enrolled in Behavioral Neuroscience at Connecticut College were provided with a home-based personal EEG monitor used to collect sleep data in their natural sleep setting. Participants recorded sleep data with the use of the ZEO® Personal Sleep Coach system and completed a nightly sleep journal questionnaire for seven nights. The ZEO® system uses EEG patterns to define sleep stages including wakefulness, light, deep and REM sleep. The journal included questions about factors known to affect sleep such as stress, caffeine, academic activity, exercise and alcohol. A class data set was compiled and used by students to perform univariate correlations examining the relationships between ZEO® variables and sleep journal variables. The data set allowed students to choose specific variables to investigate, analyze and write a peer-reviewed style manuscript. Significant class-wide correlations were found between specific sleep stages and behavioral variables suggesting that the ZEO® system is sophisticated yet inexpensive enough to be used as an effective tool in the classroom setting. Overall student feedback on the exercise was positive with many students indicating that it significantly enhanced their understanding of sleep architecture and made them keenly aware of the factors that affect quality of sleep.

  6. Effect of chronic electrical stimulation of the centromedian thalamic nuclei on various intractable seizure patterns: I. Clinical seizures and paroxysmal EEG activity.

    Science.gov (United States)

    Velasco, F; Velasco, M; Velasco, A L; Jiménez, F

    1993-01-01

    Twenty-three patients with various intractable seizure patterns were divided into four groups based on their most frequent seizure type and their clinical and EEG response to chronic electrical stimulation of the centromedian thalamic nuclei (ESCM): group A, generalized tonic-clonic (GTC, n = 9); group B, partial motor (Rasmussen type) (n = 3); group C, complex partial seizures (CPS, n = 5); and group D, generalized tonic seizures (Lennox-Gastaut type) (n = 6). CM were radiologically and electrophysiologically localized by means of stereotaxic landmarks and by thalamically induced scalp recruiting-like responses and desynchronization. ESCM consisted of daily 2-h stimulation sessions for 3 months. Each stimulus consisted of a 1-min train of square pulses with a 4-min interstimulus interval, alternating right and left CM. Each pulse was 1.0 ms in duration at 60/s frequency and 8-15 V (400-1,250 microA) amplitude. Voltage (V), current flow (microA) and impedance (k omega) at the electrode tips were kept constant. A significant decrease in the number of seizures per month and paroxysmal EEG waves per 10-s spochs occurred in group A patients between the baseline period (BL) and the ESCM period. These changes persisted for > 3 months after discontinuation of ESCM (poststimulation period, Post). Post was accompanied by a significant decrease in the number of paroxysmal EEG discharges. A substantial decrease in seizures and paroxysmal discharges was also observed in patients of group B. In contrast, patients of groups C and D showed no significant changes from BL to ESCM and Post periods, except for a significant decrease in the number of seizures in group D patients from BL to Post periods.

  7. Hemodynamic Changes After Static and Dynamic Exercises and Treadmill Stress Test; Different Patterns in Patients with Primary Benign Exertional Headache?

    Directory of Open Access Journals (Sweden)

    Mohsen Rostami

    2012-06-01

    Full Text Available The pathophysiology of primary benign exertional headache (EH is not still clearly defined. Some researchers have suggested an impaired vascular response as the etiology of this disorder. In this study we investigated whether there are any differences in blood pressure (BP and heart rate (HR of the subjects in course of the static and dynamic exercises and the treadmill stress test between those with and without EH. From university students, 22 patients with EH (mean age: 19.8 ± 2.10, Female to Male: 7:15 and 20 normal subjects (mean age: 19.3 ± 1.97, Female: Male: 8:12 were recruited. All the subjects performed the static and dynamic exercises at 30 and 20 percent of the maximal voluntary contraction (MVC and Bruce treadmill stress test according to the standard protocols. HR and BP of all the cases at the baseline and during and immediately after each test were measured. No significant difference was found between the mean rise of HR, systolic and diastolic BP of the subjects with and without EH in static and dynamic exercises and also treadmill stress test. It seems that between those with and without EH, there is no significant difference in rise of HR and BP response to static and dynamic exercises and treadmill stress test. Further studies are required to find the pathophysiology and risk factors of EH.

  8. Mating signals indicating sexual receptiveness induce unique spatio-temporal EEG theta patterns in an anuran species.

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    Guangzhan Fang

    Full Text Available Female mate choice is of importance for individual fitness as well as a determining factor in genetic diversity and speciation. Nevertheless relatively little is known about how females process information acquired from males during mate selection. In the Emei music frog, Babina daunchina, males normally call from hidden burrows and females in the reproductive stage prefer male calls produced from inside burrows compared with ones from outside burrows. The present study evaluated changes in electroencephalogram (EEG power output in four frequency bands induced by male courtship vocalizations on both sides of the telencephalon and mesencephalon in females. The results show that (1 both the values of left hemispheric theta relative power and global lateralization in the theta band are modulated by the sexual attractiveness of the acoustic stimulus in the reproductive stage, suggesting the theta oscillation is closely correlated with processing information associated with mate choice; (2 mean relative power in the beta band is significantly greater in the mesencephalon than the left telencephalon, regardless of reproductive status or the biological significance of signals, indicating it is associated with processing acoustic features and (3 relative power in the delta and alpha bands are not affected by reproductive status or acoustic stimuli. The results imply that EEG power in the theta and beta bands reflect different information processing mechanisms related to vocal recognition and auditory perception in anurans.

  9. Phase Spectral Analysis of EEG Signals

    Institute of Scientific and Technical Information of China (English)

    YOURong-yi; CHENZhong

    2004-01-01

    A new method of phase spectral analysis of EEG is proposed for the comparative analysis of phase spectra between normal EEG and epileptic EEG signals based on the wavelet decomposition technique. By using multiscale wavelet decomposition, the original EEGs are mapped to an orthogonal wavelet space, such that the variations of phase can be observed at multiscale. It is found that the phase (and phase difference) spectra of normal EEGs are distinct from that of epileptic EEGs. That is the variations of phase (and phase difference) of normal EEGs have a distinct periodic pattern with the electrical activity proceeds in the brain, but do not the epileptic EEGs. For epileptic EEGs, only at those transient points, the phase variations are obvious. In order to verify these results with the observational data, the phase variations of EEGs in principal component space are observed and found that, the features of phase spectra is in correspondence with that the wavelet space. These results make it possible to view the behavior of EEG rhythms as a dynamic spectrum.

  10. Ictal EEG modifications in temporal lobe epilepsy.

    Science.gov (United States)

    Pelliccia, Veronica; Mai, Roberto; Francione, Stefano; Gozzo, Francesca; Sartori, Ivana; Nobili, Lino; Lo Russo, Giorgio; Pizzanelli, Chiara; Tassi, Laura

    2013-12-01

    Temporal lobe epilepsy is the most common type of epilepsy in adults with medically intractable, localisation-related epilepsy, amenable to surgery. Together with clinical and neuroimaging data, presurgical ictal scalp-EEG findings are often sufficient to define the epileptogenic zone. It is widely believed that ictal scalp-EEG findings in temporal lobe epilepsy are represented by 5-9-Hz lateralised rhythmic theta activity or 2-5-Hz lateralised rhythmic delta activity. On the basis of experimental models and experience with intra-cerebral EEG recordings, the pattern of low-voltage fast activity is considered to be the electrophysiological hallmark of the epileptogenic zone. We reviewed the ictal scalp-EEG data relating to 111 seizures in 47 patients with temporal lobe epilepsy who underwent video-EEG recordings during presurgical work-up. We found that 35 patients (74.4%) showed flattening, low-voltage fast activity or fast activity as the initial EEG pattern. When visible, the rhythmic delta or theta activity followed the fast activity. Low-voltage fast activity, flattening or fast activity occurs in the majority of patients with temporal lobe epilepsy and represents the main ictal EEG pattern. Low-voltage fast activity (or similar) is also identifiable as the initial ictal EEG pattern in scalp-EEG recordings.

  11. Is "Benign Childhood Epilepsy with Centrotemporal Spikes” Always Benign?

    Directory of Open Access Journals (Sweden)

    Muhammad SAEED

    2014-07-01

    Full Text Available How to Cite This Article: Saeed M, Azam M, Shabbir N, Qamar ShA. Is "Benign Childhood Epilepsy with Centrotemporal Spikes" Always Benign? Iran J Child Neurol. 2014 Summer;8(3: 39-45.AbstractObjectiveTo determine the prevalence of associated behavioral problems and prognosis with Benign Childhood Epilepsy with CentroTemporal Spikes (BCECTS.Descriptive, Cross Sectional study that was conducted from October 2009 to April 2013 in the Department of Pediatric Neurology, the Children’s Hospital Taif, KSA.Material & MethodsThis study was conducted after approval from the Ethics Committee of the Children’s Hospital Taif, Saudi Arabia. Thirty-two patients from the age of 3 to 10 years old were recruited from the pediatric neurology clinic over a period of 4 years. All the patients were selected based on history, EEGs, and neuropsychological and neurological examinations.EEGs were performed for all the patients while in awake and sleep states. Those who had centrotemporal discharges were included in the study. All the patients also underwent a brain MRI. Only two patients had mild cortical atrophy but developmentally they were normal.ResultsIn our study, prevalence of BRE is 32/430 (7.44%. Among the 32 cases, 24 were male and eight were female. Six cases out of 32 indicated a family history of BRE. Twenty-eight cases had unilateral right sided centrotemporal discharges and four had bilateral discharges.ConclusionIt is possible that for BECTS, a high number of seizures might play an important role in the development of mild cognitive impairment and/or behavior disturbances.ReferencesBradley WG, Daroff RB, Fenichel JM, Jahrovic J. Neurology of clinical practice. 5th Ed. 2009: pp. 1953-1990.Berg AT, Berkovic SF, Brodie MJ, Buchhalter J, Cross H, Van Emde Boas M, et al: Revised terminology and concepts for organization of seizures and epilepsies: Report of the ILAE Commission on Classification and Terminology, 2005–2009. Epilepsia. 2010

  12. Developmental Venous Anomaly: Benign or Not Benign

    Science.gov (United States)

    AOKI, Rie; SRIVATANAKUL, Kittipong

    2016-01-01

    Developmental venous anomalies (DVAs), previously called venous angiomas, are the most frequently encountered cerebral vascular malformations. However, DVA is considered to be rather an extreme developmental anatomical variation of medullary veins than true malformation. DVAs are composed of dilated medullary veins converging centripetally into a large collecting venous system that drains into the superficial or deep venous system. Their etiology and mechanism are generally accepted that DVAs result from the focal arrest of the normal parenchymal vein development or occlusion of the medullary veins as a compensatory venous system. DVAs per se are benign and asymptomatic except for under certain unusual conditions. The pathomechanisms of symptomatic DVAs are divided into mechanical, flow-related causes, and idiopathic. However, in cases of DVAs associated with hemorrhage, cavernous malformations (CMs) are most often the cause rather than DVAs themselves. The coexistence of CM and DVA is common. There are some possibilities that DVA affects the formation and clinical course of CM because CM related to DVA is generally located within the drainage territory of DVA and is more aggressive than isolated CM in the literature. Brain parenchymal abnormalities surrounding DVA and cerebral varix have also been reported. These phenomena are considered to be the result of venous hypertension associated with DVAs. With the advance of diagnostic imagings, perfusion study supports this hypothesis demonstrating that some DVAs have venous congestion pattern. Although DVAs should be considered benign and clinically silent, they can have potential venous hypertension and can be vulnerable to hemodynamic changes. PMID:27250700

  13. Benign positional vertigo

    Science.gov (United States)

    Vertigo - positional; Benign paroxysmal positional vertigo; BPPV: dizziness- positional ... Benign positional vertigo is also called benign paroxysmal positional vertigo (BPPV). It is caused by a problem in the inner ear. ...

  14. Pitfalls in ictal EEG interpretation: critical care and intracranial recordings.

    Science.gov (United States)

    Gaspard, Nicolas; Hirsch, Lawrence J

    2013-01-01

    EEG is the cornerstone examination for seizure diagnosis, especially nonconvulsive seizures in the critically ill, but is still subject to many errors that can lead to a wrong diagnosis and unnecessary or inadequate treatment. Many of these pitfalls to EEG interpretation are avoidable. This article reviews common errors in EEG interpretation, focusing on ictal or potentially ictal recordings obtained in critically ill patients. Issues discussed include artifacts, nonepileptic events, equivocal EEG patterns seen in comatose patients, and quantitative EEG artifacts. This review also covers some difficulties encountered with intracranial EEG recordings in patients undergoing epilepsy surgery, including issues related to display resolution.

  15. Benign childhood epilepsy with centro-temporal spikes: correlation between clinical, cognitive and EEG aspects Epilepsia benigna da infância com pontas centrotemporais: correlação entre aspectos clínicos, eletrencefalográficos e cognitivos

    Directory of Open Access Journals (Sweden)

    Lineu Corrêa Fonseca

    2007-09-01

    Full Text Available Benign childhood epilepsy with centro-temporal spikes (BECTS is a form of epilepsy with no demonstrable anatomical lesion showing spontaneous seizure remission. During the active phase of the disease the children may show cognitive deficits. The objective of this study was to assess, in children with BECTS, the relationship between clinical-EEG aspects and performance in the school performance test (SPT, Raven's progressive matrixes test and the Wechsler Intelligence Scale for Children (WISC-III. Forty-two 7 to 11 year old children were included and the following tests carried out: anamnesis, neurological examination, electroencephalogram (EEG, SPT, Raven's test and WISC-III. The children with BECTS had normal IQ values but showed inferior performance in the SPT more frequently than "healthy" children, paired with respect to age and maternal scholastic level. There was moderate positive correlation between WISC-III results and the age when the seizures started and the educational level of the parents. On the other hand, aspects linked to the epileptic nature of BECTS, such as the number of seizures, time since last seizure and the number and lateralization of the centro-temporal spikes on the EEG, showed no correlation with the neuropsychological tests.A epilepsia benigna da infância com pontas centrotemporais (EBICT é uma forma de epilepsia na qual não existem lesões anatômicas demonstráveis e há remissão espontânea das crises. Na fase ativa da epilepsia as crianças podem apresentar déficits cognitivos. O objetivo deste estudo foi avaliar, em crianças com EBICT, a relação entre aspectos clínico-eletrencefalográficos e o desempenho no teste de desempenho escolar (TDE, no teste das matrizes progressivas de Raven e na Escala Wechsler de Inteligência para Crianças (WISC-III. Foram incluídas 42 crianças de 7 a 11 anos de idade. Foram realizados: anamnese, exame neurológico, eletrencefalograma (EEG, TDE, teste de Raven e WISC

  16. Electroencephalogram (EEG) (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old EEG (Electroencephalogram) KidsHealth > For Parents > EEG (Electroencephalogram) Print A A A What's in this ... Child If You Have Questions en español Electroencefalograma (EEG) What It Is An electroencephalogram (EEG) is a ...

  17. Electroencephalogram (EEG) (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old EEG (Electroencephalogram) KidsHealth > For Parents > EEG (Electroencephalogram) A A A What's in this article? ... Child If You Have Questions en español Electroencefalograma (EEG) What It Is An electroencephalogram (EEG) is a ...

  18. What can be found in scalp EEG spectrum beyond common frequency bands. EEG-fMRI study

    Science.gov (United States)

    Marecek, R.; Lamos, M.; Mikl, M.; Barton, M.; Fajkus, J.; I, Rektor; Brazdil, M.

    2016-08-01

    Objective. The scalp EEG spectrum is a frequently used marker of neural activity. Commonly, the preprocessing of EEG utilizes constraints, e.g. dealing with a predefined subset of electrodes or a predefined frequency band of interest. Such treatment of the EEG spectrum neglects the fact that particular neural processes may be reflected in several frequency bands and/or several electrodes concurrently, and can overlook the complexity of the structure of the EEG spectrum. Approach. We showed that the EEG spectrum structure can be described by parallel factor analysis (PARAFAC), a method which blindly uncovers the spatial-temporal-spectral patterns of EEG. We used an algorithm based on variational Bayesian statistics to reveal nine patterns from the EEG of 38 healthy subjects, acquired during a semantic decision task. The patterns reflected neural activity synchronized across theta, alpha, beta and gamma bands and spread over many electrodes, as well as various EEG artifacts. Main results. Specifically, one of the patterns showed significant correlation with the stimuli timing. The correlation was higher when compared to commonly used models of neural activity (power fluctuations in distinct frequency band averaged across a subset of electrodes) and we found significantly correlated hemodynamic fluctuations in simultaneously acquired fMRI data in regions known to be involved in speech processing. Further, we show that the pattern also occurs in EEG data which were acquired outside the MR machine. Two other patterns reflected brain rhythms linked to the attentional and basal ganglia large scale networks. The other patterns were related to various EEG artifacts. Significance. These results show that PARAFAC blindly identifies neural activity in the EEG spectrum and that it naturally handles the correlations among frequency bands and electrodes. We conclude that PARAFAC seems to be a powerful tool for analysis of the EEG spectrum and might bring novel insight to the

  19. Mobile EEG in epilepsy

    NARCIS (Netherlands)

    Askamp, Jessica; Putten, van M.J.A.M.

    2014-01-01

    The sensitivity of routine EEG recordings for interictal epileptiform discharges in epilepsy is limited. In some patients, inpatient video-EEG may be performed to increase the likelihood of finding abnormalities. Although many agree that home EEG recordings may provide a cost-effective alternative t

  20. Connectivity measures in EEG microstructural sleep elements

    Directory of Open Access Journals (Sweden)

    Dimitris eSakellariou

    2016-02-01

    Full Text Available During Non-Rapid Eye Movement sleep (NREM the brain is relatively disconnected from the environment, while connectedness between brain areas is also decreased. Evidence indicates that these dynamic connectivity changes are delivered by microstructural elements of sleep: short periods of environmental stimuli evaluation followed by sleep promoting procedures. The connectivity patterns of the latter, among other aspects of sleep microstructure, are still to be fully elucidated.We suggest here a methodology for the assessment and investigation of the connectivity patterns of EEG microstructural elements, such as sleep spindles. The methodology combines techniques in the preprocessing, estimation, error assessing and visualization of results levels in order to allow the detailed examination of the connectivity aspects (levels and directionality of information flow over frequency and time with notable resolution, while dealing with the volume conduction and EEG reference assessment. The high temporal and frequency resolution of the methodology will allow the association between the microelements and the dynamically forming networks that characterise them, and consequently possibly reveal aspects of the EEG microstructure. The proposed methodology is initially tested on artificially generated signals for proof of concept and subsequently applied to real EEG recordings via a custom built MATLAB-based tool developed for such studies. Preliminary results from 843 fast sleep spindles recorded in whole night sleep of 5 healthy volunteers indicate a prevailing pattern of interactions between centroparietal and frontal regions.We demonstrate hereby an opening to our knowledge attempt to estimate the scalp EEG connectivity that characterizes fast sleep spindles via an EEG-element connectivity methodology we propose. The application of the latter, via a computational tool we developed suggests it is able to investigate the connectivity patterns related to the

  1. Tackling creativity at its roots: evidence for different patterns of EEG α activity related to convergent and divergent modes of task processing.

    Science.gov (United States)

    Jauk, Emanuel; Benedek, Mathias; Neubauer, Aljoscha C

    2012-05-01

    The distinction between convergent and divergent cognitive processes given by Guilford (1956) had a strong influence on the empirical research on creative thinking. Neuroscientific studies typically find higher event-related synchronization in the EEG alpha rhythm for individuals engaged in creative ideation tasks compared to intelligence-related tasks. This study examined, whether these neurophysiological effects can also be found when both cognitive processing modes (convergent vs. divergent) are assessed by means of the same task employing a simple variation of instruction. A sample of 55 participants performed the alternate uses task as well as a more basic word association task while EEG was recorded. On a trial-by-trial basis, participants were either instructed to find a most common solution (convergent condition) or a most uncommon solution (divergent condition). The answers given in the divergent condition were in both tasks significantly more original than those in the convergent condition. Moreover, divergent processing was found to involve higher task-related EEG alpha power than convergent processing in both the alternate uses task and the word association task. EEG alpha synchronization can hence explicitly be associated with divergent cognitive processing rather than with general task characteristics of creative ideation tasks. Further results point to a differential involvement of frontal and parietal cortical areas by individuals of lower versus higher trait creativity.

  2. Correlation of invasive EEG and scalp EEG.

    Science.gov (United States)

    Ramantani, Georgia; Maillard, Louis; Koessler, Laurent

    2016-10-01

    Ever since the implementation of invasive EEG recordings in the clinical setting, it has been perceived that a considerable proportion of epileptic discharges present at a cortical level are missed by routine scalp EEG recordings. Several in vitro, in vivo, and simulation studies have been performed in the past decades aiming to clarify the interrelations of cortical sources with their scalp and invasive EEG correlates. The amplitude ratio of cortical potentials to their scalp EEG correlates, the extent of the cortical area involved in the discharge, as well as the localization of the cortical source and its geometry have been each independently linked to the recording of the cortical discharge with scalp electrodes. The need to elucidate these interrelations has been particularly imperative in the field of epilepsy surgery with its rapidly growing EEG-based localization technologies. Simultaneous multiscale EEG recordings with scalp, subdural and/or depth electrodes, applied in presurgical epilepsy workup, offer an excellent opportunity to shed some light to this fundamental issue. Whereas past studies have considered predominantly neocortical sources in the context of temporal lobe epilepsy, current investigations have included deep sources, as in mesial temporal epilepsy, as well as extratemporal sources. Novel computational tools may serve to provide surrogates for the shortcomings of EEG recording methodology and facilitate further developments in modern electrophysiology.

  3. Prognostic value of non-reactive burst suppression EEG pattern associated to early neonatal seizures Valor prognóstico do EEG com padrão de surto-supressão não reativo associado a convulsões neonatais precoces

    Directory of Open Access Journals (Sweden)

    Magda Lahorgue Nunes

    2005-03-01

    Full Text Available ABSTRACT Seizures are the most frequent neurological event in newborns and clinical data suggest that etiology is the dominant factor in long term outcome. However, there are consistent background EEG abnormalities associated to neonatal seizures that are usually related to unfavorable outcome as the burst - suppression pattern. OBJECTIVE: The objective of this study was to correlate clinical and EEG features associated to long - term outcome of newborns with non - reactive burst - suppression (BS EEG. METHOD: Newborns included in the study were selected from our database and had conceptional age (at the time of first EEG >37 weeks, EEG recordings with non - reactive BS available for review and clinical follow up. RESULTS: 12 newborns met inclusion criteria, 50% had seizures in the first day of life. Seizures became refractory to treatment in all of them. In 50% the etiology of seizures was considered cryptogenic, 33% had inborn errors of metabolism and 17% had clinical history and neuroimage suggestive of hypoxic-ischemic encephalopathy. The follow-up showed that 7/12 infants deceased, 3 during the first year of life, and one in the neonatal period. All the survivors had severe developmental delay and multifocal neurological impairment. 92% developed refractory epilepsy, 58% were latter diagnosed with West syndrome. CONCLUSION: The non-reactive BS pattern may appear related to many neonatal neurological disorders and is associated with early and refractory neonatal seizures. It is clearly associated with elevated morbidity and mortality and to the development of post-neonatal epilepsy.RESUMO Convulsões representam o evento neurológico mais freqüente no período neonatal e a etiologia das crises parece ser o aspecto clínico mais associado ao prognóstico a longo prazo. Entretanto, existem padrões anormais de EEG, que de forma consistente relacionam-se a prognóstico, entre eles o padrão de surto - supressão. OBJETIVO: Este estudo teve

  4. THE USE OF SLEEP EEG IN EPILEPTIC DIAGNOSIS

    Institute of Scientific and Technical Information of China (English)

    刘秀琴; 周祥琴; 吴立文; 王平; 孙鹤阳

    1998-01-01

    Sleep and waklng EEG of 522 patients with epilepsy and various disease with attack nature were studled, EEG showed paroxysmal activities(PA) in 2]7 cases. PA appeared only during sleep in 96 cases, posirive rate of EEG diagnosis increased from 23.2 percent in waking recordings to 41.6 percent, Fifty of 97 benign childhood epilepsy with centrotemporal spike(5l.6%) had focal PA only during sleep. Two of 6 cases with Lennox-Gastaut syndrome showed tonic seizure and/or generalized paroxysmal fast activities,Seizure types of 15 patients were deigned hy interictal PA and ictal EEG during sleep. There was no corresponding relationship between seizure time(waking or sleep) and PA sensitivity to state of vigilance.

  5. Tackling creativity at its roots: Evidence for different patterns of EEG alpha activity related to convergent and divergent modes of task processing

    OpenAIRE

    2012-01-01

    The distinction between convergent and divergent cognitive processes given by Guilford (1956) had a strong influence on the empirical research on creative thinking. Neuroscientific studies typically find higher event-related synchronization in the EEG alpha rhythm for individuals engaged in creative ideation tasks compared to intelligence-related tasks. This study examined, whether these neurophysiological effects can also be found when both cognitive processing modes (convergent vs. divergen...

  6. Correlation between intra- and extracranial background EEG

    DEFF Research Database (Denmark)

    Duun-Henriksen, Jonas; Kjær, Troels Wesenberg; Madsen, Rasmus Elsborg

    2012-01-01

    Scalp EEG is the most widely used modality to record the electrical signals of the brain. It is well known that the volume conduction of these brain waves through the brain, cerebrospinal fluid, skull and scalp reduces the spatial resolution and the signal amplitude. So far the volume conduction...... has primarily been investigated by realistic head models or interictal spike analysis. We have set up a novel and more realistic experiment that made it possible to compare the information in the intra- and extracranial EEG. We found that intracranial EEG channels contained correlated patterns when...... placed less than 30 mm apart, that intra- and extracranial channels were partly correlated when placed less than 40 mm apart, and that extracranial channels probably were correlated over larger distances. The underlying cortical area that influences the extracranial EEG is found to be up to 45 cm2...

  7. Sleep EEG patterns and fatigue of middle-aged and older female family caregivers providing routine nighttime care for elderly persons at home.

    Science.gov (United States)

    Sato, Reiko; Kanda, Katsuya; Anan, Mitoko; Watanuki, Shigeaki

    2002-12-01

    The sleep EEGs and fatigue of 9 female family caregivers (age M=65 yr.) and 9 female noncaregivers (age M=67 yr.) were measured during two successive nights at their houses. Perceived quality of sleep was measured by the Sleep Evaluation Questionnaire. Fatigue was measured by a self-rated questionnaire, the Perceived Symptoms of Fatigue, and by critical flicker fusion (CFF) frequency. The caregivers had a significantly higher percentage of Stage 1 and a lower percentage of Stage 2 during the 2nd cycle and a higher percentage of Stages 3+4 during the 3rd cycle than those of the noncaregivers. Caregivers had significantly higher percentages of EEG waves of 7-9 Hz in the 1st cycle and 6-9 Hz in the 2nd cycle and significantly lower percentages of 2-3 Hz in the 1st cycle than those of the noncaregivers. The caregivers reported a lower quality of sleep and higher perceived fatigue symptoms and also lower CFF frequency (increased physiological fatigue) than noncaregivers. The caregivers' sleep EEGs were associated with their higher sleep needs and fatigue.

  8. Benign Paroxysmal Positional Vertigo (BPPV)

    Science.gov (United States)

    ... Rated Nonprofit! Volunteer. Donate. Review. Benign Paroxysmal Positional Vertigo (BPPV) BPPV is the most common vestibular disorder. Benign ... al. Diagnosis and management of benign paroxysmal positional vertigo (BPPV). CMAJ. 2003 169(7):681-693. Nuti D, ...

  9. The Etiology and Outcome Analysis of Neonatal Burst Suppression EEG

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lian; ZHOU Yanxia; XU Sanqing

    2007-01-01

    The neonatal burst suppression is a severe EEG pattern and always demonstrates serious damage of nerve system. But the outcome of these patients depends on the different etiology. A total of 256 cases of video EEG recordings were analyzed in order to summarize the etiology and outcome of burst suppression. The results showed that some patients in all 17 cases of burst suppression showed EEG improvement. The etiology was the dominant factor in long term outcome. It was sug-gested that effective video EEG monitoring is helpful for etiologic study and prognosis evaluation.

  10. Unified EEG terminology and criteria for nonconvulsive status epilepticus.

    Science.gov (United States)

    Beniczky, Sándor; Hirsch, Lawrence J; Kaplan, Peter W; Pressler, Ronit; Bauer, Gerhard; Aurlien, Harald; Brøgger, Jan C; Trinka, Eugen

    2013-09-01

    The diagnosis of nonconvulsive status epilepticus (NCSE) relies largely on electroencephalography (EEG) findings. The lack of a unified EEG terminology, and of evidence-based EEG criteria, leads to varying criteria for and ability to diagnose NCSE. We propose a unified terminology and classification system for NCSE, using, as a template, the Standardised Computer-based Organised Reporting of EEG (SCORE). This approach integrates the terminology recently proposed for the rhythmic and periodic patterns in critically ill patients, the electroclinical classification of NCSE (type of NCSE) and the context for the pathologic conditions and age-related epilepsy syndromes. We propose flexible EEG criteria that employ the SCORE system to assemble a database for determining evidence-based EEG criteria for NCSE.

  11. EEG and Coma.

    Science.gov (United States)

    Ardeshna, Nikesh I

    2016-03-01

    Coma is defined as a state of extreme unresponsiveness, in which a person exhibits no voluntary movement or behavior even to painful stimuli. The utilization of EEG for patients in coma has increased dramatically over the last few years. In fact, many institutions have set protocols for continuous EEG (cEEG) monitoring for patients in coma due to potential causes such as subarachnoid hemorrhage or cardiac arrest. Consequently, EEG plays an important role in diagnosis, managenent, and in some cases even prognosis of coma patients.

  12. Benign prostate hyperplasia (BPH) - resources

    Science.gov (United States)

    Resources - benign prostatic hyperplasia (BPH); Prostate enlargement resources; BPH resources ... The following organizations provide information on benign prostatic hyperplasia ( prostate enlargement ... Urology Care Foundation -- www. ...

  13. Screening EEG in Aircrew Selection: Clinical Aerospace Neurology Perspective

    Science.gov (United States)

    Clark, Jonathan B.; Riley, Terrence

    2001-01-01

    .0139% (4/28627). After review of the value of the EEG as a screening tool, the US Navy now uses EEG only for certain clinical indications (head injury, unexplained loss of consciousness, family history of epilepsy, and abnormal neurological exam). Currently the US Navy does not use EEG for screening for any flight applicant without a neurologic indication. In the US Navy, an electroencephalographic pattern is determined to be epileptiform by a neurologist.

  14. Benign positional vertigo - aftercare

    Science.gov (United States)

    Vertigo - positional - aftercare; Benign paroxysmal positional vertigo - aftercare; BPPV - aftercare; Dizziness - positional vertigo ... Your health care provider may have treated your vertigo with the Epley maneuver . These are head movements ...

  15. Computer database of ambulatory EEG signals.

    Science.gov (United States)

    Jayakar, P B; Brusse, E; Patrick, J P; Shwedyk, E; Seshia, S S

    1987-01-01

    The paper describes an ambulatory EEG database. The database contains segments of AEEGs done on 45 subjects. Each epoch (1/8th second or more) of AEEG data has been annotated into 1 of 40 classes. The classes represent background activity, paroxysmal patterns and artifacts. The majority of classes have over 200 discrete epochs. The structure is flexible enough to allow additional epochs to be readily added. The database is stored on transportable media such as digital magnetic tape or hard disk and is thus available to other researchers in the field. The database can be used to design, evaluate and compare EEG signal processing algorithms and pattern recognition systems. It can also serve as an educational medium in EEG laboratories.

  16. EEG: Origin and measurement

    NARCIS (Netherlands)

    Lopes da Silva, F.; Mulert, C.; Lemieux, L.

    2010-01-01

    The existence of the electrical activity of the brain (i.e. the electroencephalogram or EEG) was discovered more than a century ago by Caton. After the demonstration that the EEG could be recorded from the human scalp by Berger in the 1920s, it made a slow start before it became accepted as a method

  17. EEG as an Indicator of Cerebral Functioning in Postanoxic Coma.

    Science.gov (United States)

    Juan, Elsa; Kaplan, Peter W; Oddo, Mauro; Rossetti, Andrea O

    2015-12-01

    Postanoxic coma after cardiac arrest is one of the most serious acute cerebral conditions and a frequent cause of admission to critical care units. Given substantial improvement of outcome over the recent years, a reliable and timely assessment of clinical evolution and prognosis is essential in this context, but may be challenging. In addition to the classic neurologic examination, EEG is increasingly emerging as an important tool to assess cerebral functions noninvasively. Although targeted temperature management and related sedation may delay clinical assessment, EEG provides accurate prognostic information in the early phase of coma. Here, the most frequently encountered EEG patterns in postanoxic coma are summarized and their relations with outcome prediction are discussed. This article also addresses the influence of targeted temperature management on brain signals and the implication of the evolution of EEG patterns over time. Finally, the article ends with a view of the future prospects for EEG in postanoxic management and prognostication.

  18. Benign nontraumatic osteolytic vertebral collapse simulating malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Sattari, Azadeh [Hopital Lariboisiere, Department of Musculoskeletal Radiology, Paris Cedex 10 (France); Quillard, Alain [Hopital Lariboisiere, Department of Pathology, Paris Cedex 10 (France); Laredo, Jean-Denis [Hopital Lariboisiere, Department of Musculoskeletal Radiology, Paris Cedex 10 (France); University of Pennsylvania Health System, Department of Radiology, Philadelphia, PA (United States)

    2008-03-15

    This study described the imaging features of a distinctive pattern of biopsy-proven benign non-traumatic vertebral collapse (VC) that can mimic malignancy. Among 240 patients referred with painful VC over a 10-year period, we retrospectively selected 15 cases of benign VC which simulated malignancy, due to cortical bone destruction on radiographs. The diagnosis of benign origin was documented by percutaneous biopsy and 12-months of follow-up. Radiographs, CT and MR images of the spine were reviewed. Findings suggestive of malignancy included destruction involving the anterolateral cortex, posterior cortex and pedicles of the vertebral body (46%,15% and 15% respectively) at CT, epidural soft-tissue masses on CT (23%) and MR images (21%), and diffuse low signal-intensity (SI) of the vertebral body (50%) and pedicles (79%) on T1-weighted images. Features suggestive of a benign origin included an intravertebral vacuum phenomenon on radiographs and CT (13%), fracture lines within the vertebral body (92%) or pedicles (62%) at CT and presence an intravertebral area of high SI on T2-weighted images (93%). Benign non-traumatic osteolytic VC can simulate malignancy on radiographs. The features, above mentioned on CT and MR suggestive of a benign VC, are useful in interpreting biopsy results of such lesions and avoiding unnecessary repeat biopsy. (orig.)

  19. Somatosensory-evoked spikes on electroencephalography (EEG): longitudinal clinical and EEG aspects in 313 children.

    Science.gov (United States)

    Fonseca, Lineu Corrêa; Tedrus, Gloria M A S

    2012-01-01

    Somatosensory-evoked spikes (ESp) are high-voltage potentials registered on the EEG, which accompany each of the percussions on the feet or hands. The objective of this research was to study the longitudinal clinical and EEG aspects of children with ESp. A total of 313 children, 53.7% male, showing ESp on the EEG and with an average initial age of 6.82 (range from 2 to 14 years) were followed for a mean period of 35.7 months. In the initial evaluation, 118 (37.7%) had a history of nonfebrile epileptic seizures (ES). Epileptiform activity (EA) was observed on the EEG in 61% and showed a significantly greater occurrence in children with ES than in those without (P = .000). Of the 118 showing seizures from the start, 53 (44.9%) continued to have seizures; of the 195 without seizures at the start, only 13 (6.67%) developed them. Thus, only 66 (21.1%) children showed ES during the follow-up. ESp disappeared in 237 (75.7%) cases and EA in 221 (70.6%). In the children with ES, it was found that the presence of EA on the first EEG did not indicate continuation of the ES throughout the remaining period, while the 13 children who presented their first ES in a later period showed a greater occurrence of EA on the initial EEG than those who did not develop ES (P = .001). Evidence of brain injury was observed in 43 (13.7%) children and was associated with a greater continuity of the ES during the study (P = .018). ESp, EA, and ES tend to disappear, suggesting an age-dependent phenomenon. The finding of ESp, particularly in the absence of any evidence of brain injury, indicates a low association with ES and benign outcome.

  20. The Mozart Effect: A quantitative EEG study.

    Science.gov (United States)

    Verrusio, Walter; Ettorre, Evaristo; Vicenzini, Edoardo; Vanacore, Nicola; Cacciafesta, Mauro; Mecarelli, Oriano

    2015-09-01

    The aim of this study is to investigate the influence of Mozart's music on brain activity through spectral analysis of the EEG in young healthy adults (Adults), in healthy elderly (Elderly) and in elderly with Mild Cognitive Impairment (MCI). EEG recording was performed at basal rest conditions and after listening to Mozart's K448 or "Fur Elise" Beethoven's sonatas. After listening to Mozart, an increase of alpha band and median frequency index of background alpha rhythm activity (a pattern of brain wave activity linked to memory, cognition and open mind to problem solving) was observed both in Adults and in Elderly. No changes were observed in MCI. After listening to Beethoven, no changes in EEG activity were detected. This results may be representative of the fact that said Mozart's music is able to "activate" neuronal cortical circuits related to attentive and cognitive functions.

  1. EEG entropy measures in anesthesia

    Directory of Open Access Journals (Sweden)

    Zhenhu eLiang

    2015-02-01

    Full Text Available Objective: Entropy algorithms have been widely used in analyzing EEG signals during anesthesia. However, a systematic comparison of these entropy algorithms in assessing anesthesia drugs’ effect is lacking. In this study, we compare the capability of twelve entropy indices for monitoring depth of anesthesia (DoA and detecting the burst suppression pattern (BSP, in anesthesia induced by GA-BAergic agents.Methods: Twelve indices were investigated, namely Response Entropy (RE and State entropy (SE, three wavelet entropy (WE measures (Shannon WE (SWE, Tsallis WE (TWE and Renyi WE (RWE, Hilbert-Huang spectral entropy (HHSE, approximate entropy (ApEn, sample entropy (SampEn, Fuzzy entropy, and three permutation entropy (PE measures (Shannon PE (SPE, Tsallis PE (TPE and Renyi PE (RPE. Two EEG data sets from sevoflurane-induced and isoflu-rane-induced anesthesia respectively were selected to assess the capability of each entropy index in DoA monitoring and BSP detection. To validate the effectiveness of these entropy algorithms, phar-macokinetic / pharmacodynamic (PK/PD modeling and prediction probability analysis were applied. The multifractal detrended fluctuation analysis (MDFA as a non-entropy measure was compared.Results: All the entropy and MDFA indices could track the changes in EEG pattern during different anesthesia states. Three PE measures outperformed the other entropy indices, with less baseline vari-ability, higher coefficient of determination and prediction probability, and RPE performed best; ApEn and SampEn discriminated BSP best. Additionally, these entropy measures showed an ad-vantage in computation efficiency compared with MDFA.Conclusion: Each entropy index has its advantages and disadvantages in estimating DoA. Overall, it is suggested that the RPE index was a superior measure.Significance: Investigating the advantages and disadvantages of these entropy indices could help improve current clinical indices for monitoring DoA.

  2. 基于共空间模式的四类运动想象脑电信号分类方法%Classiifcation Method of Four-Class Motor Imagery EEG Data Based on Common Spatial Pattern

    Institute of Scientific and Technical Information of China (English)

    李立亭

    2016-01-01

    针对多通道四类运动想象脑电信号分类问题,使用共空间模式的特征提取方法,设计了“一对一”和“一对多”两种特征提取策略,最后结合不同的策略设计了基于支持向量机的不同分类方法。应用提出的方法对四类运动想象脑电信号进行了特征提取和分类,两种策略下分类正确率分别为64%、59%,可见,基于“一对一”的分类结果高于“一对多”的分类结果,说明了该特征提取及分类方法对该数据集的有效性。%Aiming at the classification problem of multi-channel four-class motor imagery EEG signals, the method common spatial pattern is presented for feature extraction. In the method, two feature extraction strategies, called‘one vs one’ and‘one vs rest’ are designed, finally, different classification methods based on support vector machine classifiers are designed according to the different input features. Four-class motor imagery EEG signals are extracted and classified using the proposed method. The classification accuracy of the two methods is 64% and 59%, which show the classification results based on the‘one vs one’ are higher than the classification results of the‘one vs rest’. Respectively, which showthat the proposed method is suitable for the classification of the data.

  3. EEG Correlates of Ten Positive Emotions

    Science.gov (United States)

    Hu, Xin; Yu, Jianwen; Song, Mengdi; Yu, Chun; Wang, Fei; Sun, Pei; Wang, Daifa; Zhang, Dan

    2017-01-01

    Compared with the well documented neurophysiological findings on negative emotions, much less is known about positive emotions. In the present study, we explored the EEG correlates of ten different positive emotions (joy, gratitude, serenity, interest, hope, pride, amusement, inspiration, awe, and love). A group of 20 participants were invited to watch 30 short film clips with their EEGs simultaneously recorded. Distinct topographical patterns for different positive emotions were found for the correlation coefficients between the subjective ratings on the ten positive emotions per film clip and the corresponding EEG spectral powers in different frequency bands. Based on the similarities of the participants’ ratings on the ten positive emotions, these emotions were further clustered into three representative clusters, as ‘encouragement’ for awe, gratitude, hope, inspiration, pride, ‘playfulness’ for amusement, joy, interest, and ‘harmony’ for love, serenity. Using the EEG spectral powers as features, both the binary classification on the higher and lower ratings on these positive emotions and the binary classification between the three positive emotion clusters, achieved accuracies of approximately 80% and above. To our knowledge, our study provides the first piece of evidence on the EEG correlates of different positive emotions. PMID:28184194

  4. Higher-Order Spectrum in Understanding Nonlinearity in EEG Rhythms

    Directory of Open Access Journals (Sweden)

    Cauchy Pradhan

    2012-01-01

    Full Text Available The fundamental nature of the brain's electrical activities recorded as electroencephalogram (EEG remains unknown. Linear stochastic models and spectral estimates are the most common methods for the analysis of EEG because of their robustness, simplicity of interpretation, and apparent association with rhythmic behavioral patterns in nature. In this paper, we extend the use of higher-order spectrum in order to indicate the hidden characteristics of EEG signals that simply do not arise from random processes. The higher-order spectrum is an extension Fourier spectrum that uses higher moments for spectral estimates. This essentially nullifies all Gaussian random effects, therefore, can reveal non-Gaussian and nonlinear characteristics in the complex patterns of EEG time series. The paper demonstrates the distinguishing features of bispectral analysis for chaotic systems, filtered noises, and normal background EEG activity. The bispectrum analysis detects nonlinear interactions; however, it does not quantify the coupling strength. The squared bicoherence in the nonredundant region has been estimated to demonstrate nonlinear coupling. The bicoherence values are minimal for white Gaussian noises (WGNs and filtered noises. Higher bicoherence values in chaotic time series and normal background EEG activities are indicative of nonlinear coupling in these systems. The paper shows utility of bispectral methods as an analytical tool in understanding neural process underlying human EEG patterns.

  5. Benign Fibrous Histiocytoma

    Directory of Open Access Journals (Sweden)

    Pushpa Varma

    2014-01-01

    Full Text Available Fibrous histiocytomas (FHs are mesenchymal tumors that may be benign or malignant. Ocular involvement by FHs is infrequent and primarily limited to the orbit. Rarely, FHs can also involve the conjunctiva and perilimbal area. We report the case of a 38-year-old male with lid, conjunctival, and neck FHs. The diagnosis was confirmed by histopathology.

  6. Benign Prostatic Hyperplasia

    Science.gov (United States)

    ... prostate gets bigger, it may press on the urethra and cause the flow of urine to be slower and less forceful. "Benign" means the enlargement isn't caused by cancer or infection. "Hyperplasia" means enlargement. SymptomsWhat are the ...

  7. Hypoglycemia-Associated EEG Changes in Prepubertal Children With Type 1 Diabetes

    DEFF Research Database (Denmark)

    Hansen, Grith Lærkholm; Foli-Andersen, Pia; Fredheim, Siri

    2016-01-01

    BACKGROUND: The purpose of this study was to explore the possible difference in the electroencephalogram (EEG) pattern between euglycemia and hypoglycemia in children with type 1 diabetes (T1D) during daytime and during sleep. The aim is to develop a hypoglycemia alarm based on continuous EEG...... measurement and real-time signal processing. METHOD: Eight T1D patients aged 6-12 years were included. A hyperinsulinemic hypoglycemic clamp was performed to induce hypoglycemia both during daytime and during sleep. Continuous EEG monitoring was performed. For each patient, quantitative EEG (qEEG) measures...

  8. Demonstration of brain noise on human EEG signals in perception of bistable images

    Science.gov (United States)

    Grubov, Vadim V.; Runnova, Anastasiya E.; Kurovskaya, Maria K.; Pavlov, Alexey N.; Koronovskii, Alexey A.; Hramov, Alexander E.

    2016-03-01

    In this report we studied human brain activity in the case of bistable visual perception. We proposed a new approach for quantitative characterization of this activity based on analysis of EEG oscillatory patterns and evoked potentials. Accordingly to theoretical background, obtained experimental EEG data and results of its analysis we studied a characteristics of brain activity during decision-making. Also we have shown that decisionmaking process has the special patterns on the EEG data.

  9. Detection of artifacts from high energy bursts in neonatal EEG.

    Science.gov (United States)

    Bhattacharyya, Sourya; Biswas, Arunava; Mukherjee, Jayanta; Majumdar, Arun Kumar; Majumdar, Bandana; Mukherjee, Suchandra; Singh, Arun Kumar

    2013-11-01

    Detection of non-cerebral activities or artifacts, intermixed within the background EEG, is essential to discard them from subsequent pattern analysis. The problem is much harder in neonatal EEG, where the background EEG contains spikes, waves, and rapid fluctuations in amplitude and frequency. Existing artifact detection methods are mostly limited to detect only a subset of artifacts such as ocular, muscle or power line artifacts. Few methods integrate different modules, each for detection of one specific category of artifact. Furthermore, most of the reference approaches are implemented and tested on adult EEG recordings. Direct application of those methods on neonatal EEG causes performance deterioration, due to greater pattern variation and inherent complexity. A method for detection of a wide range of artifact categories in neonatal EEG is thus required. At the same time, the method should be specific enough to preserve the background EEG information. The current study describes a feature based classification approach to detect both repetitive (generated from ECG, EMG, pulse, respiration, etc.) and transient (generated from eye blinking, eye movement, patient movement, etc.) artifacts. It focuses on artifact detection within high energy burst patterns, instead of detecting artifacts within the complete background EEG with wide pattern variation. The objective is to find true burst patterns, which can later be used to identify the Burst-Suppression (BS) pattern, which is commonly observed during newborn seizure. Such selective artifact detection is proven to be more sensitive to artifacts and specific to bursts, compared to the existing artifact detection approaches applied on the complete background EEG. Several time domain, frequency domain, statistical features, and features generated by wavelet decomposition are analyzed to model the proposed bi-classification between burst and artifact segments. A feature selection method is also applied to select the

  10. Association of Electroencephalography (EEG) Power Spectra with Corneal Nerve Fiber Injury in Retinoblastoma Patients.

    Science.gov (United States)

    Liu, Jianliang; Sun, Juanjuan; Diao, Yumei; Deng, Aijun

    2016-09-04

    BACKGROUND In our clinical experience we discovered that EEG band power may be correlated with corneal nerve injury in retinoblastoma patients. This study aimed to investigate biomarkers obtained from electroencephalography (EEG) recordings to reflect corneal nerve injury in retinoblastoma patients. MATERIAL AND METHODS Our study included 20 retinoblastoma patients treated at the Department of Ophthalmology, Affiliated Hospital of Weifang Medical University between 2010 and 2014. Twenty normal individuals were included in the control group. EEG activity was recorded continuously with 32 electrodes using standard EEG electrode placement for detecting EEG power. A cornea confocal microscope was used to examine corneal nerve injury in retinoblastoma patients and normal individuals. Spearman rank correlation analysis was used to analyze the correlation between corneal nerve injury and EEG power changes. The sensitivity and specificity of changed EEG power in diagnosis of corneal nerve injury were also analyzed. RESULTS The predominantly slow EEG oscillations changed gradually into faster waves in retinoblastoma patients. The EEG pattern in retinoblastoma patients was characterized by a distinct increase of delta (PEEG spectra power and negatively correlated with theta EEG spectra power. The diagnostic sensitivity and specificity by compounding in the series were 60% and 67%, respectively. CONCLUSIONS Changes in delta and theta of EEG appear to be associated with occurrence of corneal nerve injury. Useful information can be provided for evaluating corneal nerve damage in retinoblastoma patients through analyzing EEG power bands.

  11. EEG abnormalities in clinically diagnosed brain death organ donors in Iranian tissue bank.

    Science.gov (United States)

    Tavakoli, Seyed Amir Hossein; Khodadadi, Abbas; Azimi Saein, Amir Reza; Bahrami-Nasab, Hasan; Hashemi, Behnam; Tirgar, Niloufar; Nozary Heshmati, Behnaz

    2012-01-01

    Brain death is defined as the permanent, irreversible and concurrent loss of all brain and brain stem functions. Brain death diagnosis is based on clinical criteria and it is not routine to use paraclinical studies. In some countries, electroencephalogram (EEG) is performed in all patients for the determination of brain death while there is some skepticism in relying on EEG as a confirmatory test for brain death diagnosis. In this study, we assessed the validity of EEG and its abnormalities in brain death diagnosis. In this retrospective study, we used 153 EEGs from medical records of 89 brain death patients in organ procurement unit of the Iranian Tissue Bank admitted during 2002-2008. We extracted and analyzed information including EEGs, which were examined by a neurologist for waves, artifacts and EEG abnormalities. The mean age of the patients was 27.2±12.7 years. The most common cause of brain death was multiple traumas due to accident (65%). The most prevalent artifact was electrical transformer. 125 EEGs (82%) were isoelectric (ECS) and seven EEGs (5%) were depictive of some cerebral activity which upon repeat EEGs, they showed ECS patterns too. There was no relationship between cause of brain death and cerebral activity in EEGs of the patients. In this study, we could confirm ECS patterns in all brain death patients whose status had earlier been diagnosed clinically. Considering the results of this study, it seems sensible to perform EEG as a final confirmatory test as an assurance to the patients' families.

  12. Benign Prostatic Hyperplasia

    OpenAIRE

    Gil Ortega, Joan

    2015-01-01

    Benign prostatic hyperplasia (BPH) is a prevalent disease but its molecular mechanism remains unknown. Using human tissue samples from 16 patients diagnosed with BPH, we performed an ultrastructural study to clarify the mechanism and the role of glandular cells in this pathology. We have made a description of all the changes that suffers the prostatic epithelium. We have shown that the glandular architecture presents many non-physiological forms such as papillae and papillary fronds. Basal c...

  13. Invasive EEG explorations.

    Science.gov (United States)

    Taussig, D; Montavont, A; Isnard, J

    2015-03-01

    The Wada test was adapted from the procedure described by Wada in 1964. It still has a role in the prognostic evaluation of memory disorders after mesial temporal lobectomy. The test consists of injecting a short-acting anesthetic into one hemisphere, under continuous EEG monitoring and during carotid catheterization, to verify the function of contralateral structures. Intracranial EEG recordings deliver signals with few artifacts, and which are quite specific of the zone explored. Three types of electrodes are in common use: (a) foramen ovale (FO) electrodes: electrodes can be inserted directly, without any stereotactic procedure, to provide easy and comparative EEG recordings of the lower and middle portions of the temporal lobe close to the hippocampus. These allow validation of the temporal lobe origin of seizures using FO electrodes recording coupled with scalp EEG; (b): subdural strip or grip electrodes. This relatively aggressive technique carries infectious and hemorrhagic risks and does not allow the exploration of deep cortical structures. However, it permits precise functional cortical mapping via electrical stimulation because of dense and regular positioning of electrodes over the cortical convexity; (c) stereotactically implanted depth electrodes (stereo-electroencephalography [SEEG]). Electrodes are individually planned and inserted within the brain parenchyma through small burr holes. This technique is less aggressive than subdural grid exploration. However it offers relatively limited spatial sampling that may be less well adapted to precise functional evaluation. It allows recording from deep cortical structures and can be argued to be the gold standard of presurgical EEG exploration.

  14. Clinical manifestation and EEG characters of 56 cases with benign childhood epilepsy complicated with centro-temporal spikes%56例儿童良性癫痫伴中央颞区棘波患儿临床表现及脑电图特点

    Institute of Scientific and Technical Information of China (English)

    何远知; 杨斌; 张志明; 高丁

    2013-01-01

    目的 回顾性分析儿童良性癫痫伴中央颞区棘波(BECT)的临床特征及脑电图特点.方法 收集自2008年2月到2011年12月,本院神经内科住院及门诊共收治的符合BECT诊断标准并完成6个月至3年随访的56例患儿,总结其临床资料、脑电图、及治疗随访资料.结果 56例BECT患儿中,男34例,女22例;发病年龄2岁1个月~11岁6个月,中位年龄7.5岁.发作类型为部分运动性发作41例,部分继发全身性23例及两种发作类型均有8例.发作主要表现为面部抽动、流涎、喉咙出声、言语不能、眼睛斜视、眼睑眨动、肢体抽动等,发作与睡眠密切相关.发作间期脑电图背景活动正常,痫样放电在睡眠期均出现,且多在NREM期.放电部位多位于中央或中颞区,复查脑电图其异常局灶放电可在一侧或两侧半球内的中央和中颞之间移动;可暂时性消失.3例BECT变异型脑电图特点为清醒期及睡眠期中央、中颞区极高电压的棘或棘慢波频繁发放;NREM睡眠期放电指数≥50%.结论 BECT临床发作与睡眠有密切相关,脑电图检查可见限局性棘波或尖波,多位于中央区或中颞区,多数预后良好,但也有部分患者预后不良.%Objective:To retrospectively analyze the Clinical features and EEG Characters of benign childhood epilepsy Complicated with centro-tmporal spikes.Methods:56 cases with BECT who conformed to its diagnosis standard were accepted and followed up for the period from 6 months to 3 years by the neurology department of a hospital from Feb.2008 to Dec.2011 and their clinical data,electroencephalogram and follow-up information is summarized.Results:Among these 56 cases,there were 34 boys and 22 girls aged from 2 years and 1 month to 11years and 6 months with the median age of 7.5 years.41 cases are motor seizure and 23 cases are secondarily generalized seizure and 8 cases report both seizures.The seizures manifest from jerking and twitching of the

  15. Hypoglycemia-Associated EEG Changes in Prepubertal Children With Type 1 Diabetes

    DEFF Research Database (Denmark)

    Hansen, GL; Foli-Andersen, P; Fredheim, S

    2016-01-01

    BACKGROUND: The purpose of this study was to explore the possible difference in the electroencephalogram (EEG) pattern between euglycemia and hypoglycemia in children with type 1 diabetes (T1D) during daytime and during sleep. The aim is to develop a hypoglycemia alarm based on continuous EEG...... measurement and real-time signal processing. METHOD: Eight T1D patients aged 6-12 years were included. A hyperinsulinemic hypoglycemic clamp was performed to induce hypoglycemia both during daytime and during sleep. Continuous EEG monitoring was performed. For each patient, quantitative EEG (qEEG) measures...... were calculated. A within-patient analysis was conducted comparing hypoglycemia versus euglycemia changes in the qEEG. The nonparametric Wilcoxon signed rank test was performed. A real-time analyzing algorithm developed for adults was applied. RESULTS: The qEEG showed significant differences...

  16. The EEG novella 2009; Die EEG-Novelle 2009

    Energy Technology Data Exchange (ETDEWEB)

    Altrock, M.; Lehnert, W. [Kanzlei Becker Buettner Held, Berlin (Germany)

    2008-08-15

    The Renewable Energy Resources Act (EEG), already created in the year 2000, was reformed comprehensively in the year 2004. In the year 2009, a new novella of the EEG (EEG 2009) will become effective. This novella plans both an adjustment of numerous reimbursements and changes of general regulations. Furthermore, a regulation authorization was created. Due to this regulation authorization, the country wide balance regulation can be amended. At first, the authors of the contribution under consideration give an overview according to the process of legislative procedure and according to the substantial new regulations of the EEG 2009 in comparison to EEG 2004. Subsequently, individual important new regulations are discussed deeply.

  17. Radiotherapy of benign diseases

    Energy Technology Data Exchange (ETDEWEB)

    Haase, W.

    1982-10-11

    Still today radiotherapy is of decisive relevance for several benign diseases. The following ones are briefly described in this introductory article: 1. Certain inflammatory and degenerative diseases as furuncles in the face, acute thrombophlebitis, recurrent pseudoriparous abscesses, degenerative skeletal diseases, cervical syndrome and others; 2. rheumatic joint diseases; 3. Bechterew's disease; 4. primary presenile osteoporosis; 5. syringomyelia; 6. endocrine ophthalmopathy; 7. hypertrophic processes of the connective tissue; 8. hemangiomas. A detailed discussion and a profit-risk analysis is provided in the individual chapters of the magazine.

  18. Benign cephalic histiocytosis.

    Science.gov (United States)

    Gianotti, F; Caputo, R; Ermacora, E; Gianni, E

    1986-09-01

    Benign cephalic histiocytosis is a self-healing non-X, nonlipid cutaneous histiocytosis of children, characterized by a papular eruption on the head. Mucous membranes and viscera are always spared. In the 13 cases reported herein, the children were otherwise in good general health. The disease appeared during the first three years of life, and spontaneous regression was complete by the age of nine years in the four cases healed to date. The histiocytic infiltrate was localized in the upper and middle dermis and contained no lipids at any stage of evolution. All the histiocytes contained coated vesicles, and 5% to 30% also contained comma-shaped bodies in their cytoplasm.

  19. Treatment Effects on Neonatal EEG.

    Science.gov (United States)

    Obeid, Rawad; Tsuchida, Tammy N

    2016-10-01

    Conventional EEG and amplitude-integrated electroencephalography are used in neonates to assess prognosis and significant changes in brain activity. Neuroactive medications and hypothermia can influence brain activity and therefore alter EEG interpretation. There are limited studies on the effect of these therapies on neonatal EEG background activity. Medication effects on the EEG or amplitude-integrated electroencephalography include increased interburst interval duration, voltage suppression, and sleep disruption. The effect is transient in term newborns but can be persistent in premature newborns. Although therapeutic hypothermia does not produce significant changes in EEG activity, it does change the time point at which EEG can accurately predict neurodevelopmental outcome. It is important to account for these effects on the EEG to avoid inaccurate interpretation that may affect prognostication.

  20. Measurement and modification of the EEG and related behavior

    Science.gov (United States)

    Sterman, M. B.

    1991-01-01

    Electrophysiological changes in the sensorimotor pathways were found to accompany the effect of rhythmic EEG patterns in the sensorimotor cortex. Additionally, several striking behavioral changes were seen, including in particular an enhancement of sleep and an elevation of seizure threshold to epileptogenic agents. This raised the possibility that human seizure disorders might be influenced therapeutically by similar training. Our objective in human EEG feedback training became not only the facilitation of normal rhythmic patterns, but also the suppression of abnormal activity, thus requiring complex contingencies directed to the normalization of the sensorimotor EEG. To achieve this, a multicomponent frequency analysis was developed to extract and separate normal and abnormal elements of the EEG signal. Each of these elements was transduced to a specific component of a visual display system, and these were combined through logic circuits to present the subject with a symbolic display. Variable criteria provided for the gradual shaping of EEG elements towards the desired normal pattern. Some 50-70% of patients with poorly controlled seizure disorders experienced therapeutic benefits from this approach in our laboratory, and subsequently in many others. A more recent application of this approach to the modification of human brain function in our lab has been directed to the dichotomous problems of task overload and underload in the contemporary aviation environment. At least 70% of all aviation accidents have been attributed to the impact of these kinds of problems on crew performance. The use of EEG in this context has required many technical innovations and the application of the latest advances in EEG signal analysis. Our first goal has been the identification of relevant EEG characteristics. Additionally, we have developed a portable recording and analysis system for application in this context. Findings from laboratory and in-flight studies suggest that we

  1. Quantitative EEG in assessment of anaesthetic depth: comparative study of methodology

    DEFF Research Database (Denmark)

    Thomsen, C. E.; Prior, P. F.

    1996-01-01

    Methodology for assessment of depth of anaesthesia based on analysis of the electroencephalogram (EEG) is controversial. Techniques range from display of single measures, for example median value of the frequency spectrum, to dedicated pattern recognition systems based on measures of several EEG......) and (4) a depth of anaesthesia monitor based on EEG pattern recognition (ADAM). Dose-response curves are presented for stepwise increases in stable end-tidal concentrations of each agent. Results indicated considerable inter-patient variability and the limitations of single EEG measures, particularly...... with deeper anaesthesia producing a burst suppression pattern in the EEG. Pattern recognition techniques reduced these difficulties and appeared to be promising over a wide range of anaesthetic levels....

  2. The Clinical Implications of Todd Paralysis in Children With Benign Rolandic Epilepsy.

    Science.gov (United States)

    Dai, Alper I; Demiryürek, Seniz

    2016-03-01

    The aim of this study was to describe the clinical and electroencephalographic (EEG) findings of postictal Todd paralysis in benign rolandic epilepsy of childhood and find out the possible correlation with migraine. Based on International Headache Society pediatric migraine criteria, patients were investigated for migraine, and 12 of the 108 patients with benign rolandic epilepsy (6 girls and 6 boys, 11.1%) were found to have postictal Todd paralysis. Ten of these 12 patients (83.3%) had pediatric migraine based on the diagnostic criteria. We showed comorbidity of migraine and benign rolandic epilepsy with postictal Todd paralysis in children. Increased incidence of migraine in the present study suggest that children who have benign rolandic epilepsy and postictal Todd paralysis are more likely to have migraines.

  3. Diagnostic Accuracy of microEEG: A Miniature, Wireless EEG Device

    OpenAIRE

    Grant, Arthur C.; Samah G Abdel-Baki; Omurtag, Ahmet; Sinert, Richard; Chari, Geetha; Malhotra, Schweta; Weedon, Jeremy; Andre A Fenton; Zehtabchi, Shahriar

    2014-01-01

    Measuring the diagnostic accuracy (DA) of an EEG device is unconventional and complicated by imperfect interrater reliability. We sought to compare the DA of a miniature, wireless, battery-powered EEG device (“microEEG”) to a reference EEG machine in emergency department (ED) patients with altered mental status (AMS). 225 ED patients with AMS underwent 3 EEGs. EEG1 (Nicolet Monitor, “reference”) and EEG2 (microEEG) were recorded simultaneously with EEG cup electrodes using a signal splitter. ...

  4. Recording conventional and amplitude-integrated EEG in neonatal intensive care unit.

    Science.gov (United States)

    Neubauer, D; Osredkar, D; Paro-Panjan, D; Skofljanec, A; Derganc, M

    2011-09-01

    Neonatal electroencephalography (EEG) presents a challenge due to its difficult interpretation that differs significantly from interpretation in older children and adolescents. Also, from the technological point of view, it is more difficult to perform and is not a standard procedure in all neonatal intensive care units (NICUs). During recent years, long-term cerebral function monitoring by the means of amplitude-integrated EEG (aEEG) has become popular in NICUs because it is easy to apply, allows real-time interpretation by the neonatologist treating the newborn, and has predictive value for outcome. On the other side, to record conventional EEG (cEEG), which is still considered the gold standard of neonatal EEG, the EEG technician should not only be well trained in performing neonatal EEG but also has to adapt to suboptimal working conditions. These issues need to be understood when approaching the neonatal cEEG in NICU and the main structure of the article is dedicated to this technique. The authors discuss the benefits of the digitalization and its positive effects on the improvement of NICU recording. The technical aspects as well as the standards for cEEG recording are described, and a section is dedicated to possible artifacts. Thereafter, alternative and concomitant use of aEEG and its benefits are briefly discussed. At the end there is a section that presents a review of our own cEEG and aEEG recordings that were chosen as the most frequently encountered patterns according to Consensus statement on the use of EEG in the intensive care unit.

  5. Unsupervised EEG analysis for automated epileptic seizure detection

    Science.gov (United States)

    Birjandtalab, Javad; Pouyan, Maziyar Baran; Nourani, Mehrdad

    2016-07-01

    Epilepsy is a neurological disorder which can, if not controlled, potentially cause unexpected death. It is extremely crucial to have accurate automatic pattern recognition and data mining techniques to detect the onset of seizures and inform care-givers to help the patients. EEG signals are the preferred biosignals for diagnosis of epileptic patients. Most of the existing pattern recognition techniques used in EEG analysis leverage the notion of supervised machine learning algorithms. Since seizure data are heavily under-represented, such techniques are not always practical particularly when the labeled data is not sufficiently available or when disease progression is rapid and the corresponding EEG footprint pattern will not be robust. Furthermore, EEG pattern change is highly individual dependent and requires experienced specialists to annotate the seizure and non-seizure events. In this work, we present an unsupervised technique to discriminate seizures and non-seizures events. We employ power spectral density of EEG signals in different frequency bands that are informative features to accurately cluster seizure and non-seizure events. The experimental results tried so far indicate achieving more than 90% accuracy in clustering seizure and non-seizure events without having any prior knowledge on patient's history.

  6. Benign paroxysmal positional vertigo

    Directory of Open Access Journals (Sweden)

    Guo Xiang-Dong

    2011-01-01

    Full Text Available Benign paroxysmal positional vertigo (BPPV is a common clinical disorder characterized by brief recurrent spells of vertigo often brought about by certain head position changes as may occur with looking up, turning over in bed, or straightening up after bending over. It is important to understand BPPV not only because it may avert expensive and often unnecessary testing, but also because treatment is rapid, easy, and effective in >90% of cases. The diagnosis of BPPV can be made based on the history and examination. Patients usually report episodes of spinning evoked by certain movements, such as lying back or getting out of bed, turning in bed, looking up, or straightening after bending over. At present, the generally accepted recurrence rate of BPPV after successful treatment is 40%-50% at 5 years of average follow-up. There does appear to be a subset of individuals prone to multiple recurrences.

  7. Benign occipital lobe seizures: Natural progression and atypical evolution

    Directory of Open Access Journals (Sweden)

    Prithika Chary

    2013-01-01

    Full Text Available Benign occipital seizure syndromes are benign childhood epilepsy syndromes and are mainly of two types, Panayiotopoulos syndrome, an autonomic epilepsy and idiopathic childhood occipital epilepsy of Gastaut (ICOE-G including the idiopathic photosensitive occipital lobe epilepsy. Although both these types are categorized as occipital seizures, they are distinct in presentation and management. They can also be tricky to diagnose as visual symptoms may not always be the presenting feature and it is also not very easy to elicit visual hallucinations during history taking. These seizures have a good response to treatment; however, there could be atypical evolution and refractoriness to treatment especially with ICOE-G. We describe three children who presented with visual and non-visual symptoms and the electroencephalography (EEG in all the three cases showed occipital paroxysms. We have emphasized the clues in the clinical history and EEG leading to the diagnosis of these distinct epilepsy syndromes. We have also discussed the natural course of these epilepsy syndromes with some atypical evolution, which clinicians need to be aware of during treatment of these children.

  8. STUDY OF INTERICTAL E.E.G IN EPILEPSY

    Directory of Open Access Journals (Sweden)

    Usha Rani

    2013-04-01

    Full Text Available ABSTRACT: The present study includes hundred consecutive patie nts with a clinical diagnosis of Epilepsy attending the department of Neurology. All these patients were evaluated clinically and data recorded in proforma. Electroencephalogram ( E.E.G was recorded with 16-channel Electroencephalograph and the standards of normality are established. The Aim of this study is to study the pattern of abnormalities in interictal EEG in Epilepsy. The Objectives of this study are 1. To confirm the diagnosis of epilepsy. 2. To s tudy the EEG abnormalities in relation to different types of epilepsy. 3. To know the distributi on of epilepsy in relation to age and sex. 4. To study the effect of antiepileptic drugs on EEG. 5 . To study the effect of hyperventilation on EEG. 6. To study the effect of photic stimulation on EEG. 7. To study the effect of interval between last seizure and EEG recording on EEG abnor malities. Epilepsy is a very common neurological illness accounting for 10% of patients attending the Neurology Outpatient department. It most commonly affects people in the fir st 3 decades of life. Males seem to be slightly more frequently affected. The diagnosis of epilepsy is most often on clinical grounds; EEG is helpful in supporting the diagnosis of epilepsy in difficult situation and classification of the seizures. Single awake interictal recording is helpful only in approximately 40% of the patients. Provocative procedures like hyperventilation and photic stimulation increase the diagnostic yield, particularly primarily generalized epilepsies. Sleep records to be more informative should be recorded in light sleep. Gener alized seizures either primary or secondary seem to be the commonest type. In patients with a cl inical diagnosis of generalized seizures, EEG may demonstrate focal abnormalities revealing t he true nature of the seizure. Partial seizures may not reveal focal onset in the EEG maki ng classification of the seizures interacts (on

  9. EEG analyses with SOBI.

    Energy Technology Data Exchange (ETDEWEB)

    Glickman, Matthew R.; Tang, Akaysha (University of New Mexico, Albuquerque, NM)

    2009-02-01

    The motivating vision behind Sandia's MENTOR/PAL LDRD project has been that of systems which use real-time psychophysiological data to support and enhance human performance, both individually and of groups. Relevant and significant psychophysiological data being a necessary prerequisite to such systems, this LDRD has focused on identifying and refining such signals. The project has focused in particular on EEG (electroencephalogram) data as a promising candidate signal because it (potentially) provides a broad window on brain activity with relatively low cost and logistical constraints. We report here on two analyses performed on EEG data collected in this project using the SOBI (Second Order Blind Identification) algorithm to identify two independent sources of brain activity: one in the frontal lobe and one in the occipital. The first study looks at directional influences between the two components, while the second study looks at inferring gender based upon the frontal component.

  10. Motor imagery-induced EEG patterns in individuals with spinal cord injury and their impact on brain-computer interface accuracy

    Science.gov (United States)

    Müller-Putz, G. R.; Daly, I.; Kaiser, V.

    2014-06-01

    Objective. Assimilating the diagnosis complete spinal cord injury (SCI) takes time and is not easy, as patients know that there is no ‘cure' at the present time. Brain-computer interfaces (BCIs) can facilitate daily living. However, inter-subject variability demands measurements with potential user groups and an understanding of how they differ to healthy users BCIs are more commonly tested with. Thus, a three-class motor imagery (MI) screening (left hand, right hand, feet) was performed with a group of 10 able-bodied and 16 complete spinal-cord-injured people (paraplegics, tetraplegics) with the objective of determining what differences were present between the user groups and how they would impact upon the ability of these user groups to interact with a BCI. Approach. Electrophysiological differences between patient groups and healthy users are measured in terms of sensorimotor rhythm deflections from baseline during MI, electroencephalogram microstate scalp maps and strengths of inter-channel phase synchronization. Additionally, using a common spatial pattern algorithm and a linear discriminant analysis classifier, the classification accuracy was calculated and compared between groups. Main results. It is seen that both patient groups (tetraplegic and paraplegic) have some significant differences in event-related desynchronization strengths, exhibit significant increases in synchronization and reach significantly lower accuracies (mean (M) = 66.1%) than the group of healthy subjects (M = 85.1%). Significance. The results demonstrate significant differences in electrophysiological correlates of motor control between healthy individuals and those individuals who stand to benefit most from BCI technology (individuals with SCI). They highlight the difficulty in directly translating results from healthy subjects to participants with SCI and the challenges that, therefore, arise in providing BCIs to such individuals.

  11. Sleep EEG Fingerprints Reveal Accelerated Thalamocortical Oscillatory Dynamics in Williams Syndrome

    Science.gov (United States)

    Bodizs, Robert; Gombos, Ferenc; Kovacs, Ilona

    2012-01-01

    Sleep EEG alterations are emerging features of several developmental disabilities, but detailed quantitative EEG data on the sleep phenotype of patients with Williams syndrome (WS, 7q11.23 microdeletion) is still lacking. Based on laboratory (Study I) and home sleep records (Study II) here we report WS-related features of the patterns of…

  12. Maturation of EEG Power Spectra in Early Adolescence: A Longitudinal Study

    Science.gov (United States)

    Cragg, Lucy; Kovacevic, Natasa; McIntosh, Anthony Randal; Poulsen, Catherine; Martinu, Kristina; Leonard, Gabriel; Paus, Tomas

    2011-01-01

    This study investigated the fine-grained development of the EEG power spectra in early adolescence, and the extent to which it is reflected in changes in peak frequency. It also sought to determine whether sex differences in the EEG power spectra reflect differential patterns of maturation. A group of 56 adolescents were tested at age 10 years and…

  13. Effects of magnesium sulphate on amplitude-integrated continuous EEG in asphyxiated term neonates

    NARCIS (Netherlands)

    Groenendaal, F; Rademaker, CMA; Toet, MC; de Vries, LS

    2002-01-01

    In this study it is hypothesized that magnesium sulphate in asphyxiated full-term neonates could lead to a gradual improvement in background pattern of the amplitude integrated EEG (aEEG), an early marker of hypoxic-ischaemic brain injury. In a double-blind, randomized, controlled pilot study of 22

  14. Functional Brain Imaging by EEG: A Window to the Human Mind

    DEFF Research Database (Denmark)

    Stahlhut, Carsten

    be confused with each other as noise is present in the EEG recordings. Moreover, we examine how errors in the forward model affect the source confusion. The primary aim of this thesis is to provide sharper EEG brain images by improving current inverse methods. In this relation we focus the attention on two......This thesis presents electroencephalography (EEG) brain imaging by covering topics as empirical evaluation of source confusion, probabilistic inverse methods, and source analysis performed on infant EEG data. In terms of source confusion we inspect how current sources within the brain may...... topics in EEG source reconstruction, namely, the forward progation model (describing the mapping from the current sources within the brain to the sensors at the scalp) and the temporal patterns present in the EEG. As forward models may suffer from a number of errors including the geometrical...

  15. Minimal EEG montage with high yield for the detection of status epilepticus in the setting of postanoxic brain damage.

    Science.gov (United States)

    Vanherpe, Pieternel; Schrooten, Maarten

    2017-03-01

    For the diagnosis of electrographic seizures or status epilepticus, we reduced the number of EEG-electrodes to make urgent EEG monitoring more feasible. Unlike the current existing research, with mixed results, we studied a specific population with postanoxic brain damage, expecting a higher yield of detection of ictal EEG patterns. In a population treated with therapeutic hypothermia post-cardiac arrest, the initial EEGs were reformatted in a longitudinal, a hairline and an 8-lead montage, and independently reviewed by two investigators. The EEGs were categorized into three categories: one without ictal EEG activity, one with interictal activity and one with probable electrographic seizure(s). Generalized ictal EEG activity was the most frequently observed EEG pattern. The average sensitivity for the detection of probable electrographic seizure(s) was 100 % for the 8-lead montage and 92 % in the hairline montage. In comparison to the routine longitudinal montage, the 8-lead montage proved to be reliable for the detection of electrographic seizure activity in a postanoxic population even with limited training in EEG interpretation. The hairline montage did not suffice with regard to the differential diagnosis of triphasic waves associated with metabolic encephalopathy and generalized nonconvulsive status epilepticus, but nonetheless detected the vast majority of probable electrographic seizure(s). Our results support the use of EEG monitoring with fewer electrodes for the detection of ictal EEG activity in the postanoxic population.

  16. Horizontal Canal Benign Positional Vertigo

    Directory of Open Access Journals (Sweden)

    Mohtaram Najafi

    1998-03-01

    Full Text Available Benign paroxysmal positional vertigo (BPPV is a syndrome characterized by transient episodes of vertigo in association with rapid changes in head position in Dix-Halpike Maneuver. This kind of vertigo is thought to be caused by migration of otoconial debris into canals other than the posterior canal, such as the anterior or lateral canals. It is also theoretically possible for many aberrant patterns of BPPV to occur from an interaction of debris in several canals, location of debris within the canal, and central adaptation patterns to lesions. The symptoms of BPPV are much more consistent with free-moving densities (canaliths in the posterior SCC rather than fixed densities attached to the cupula. While the head is upright, the particles sit in the PSC at the most gravity-dependent position. The best method to induce and see vertigo and nystagmus in BPPV of the lateral semicircular canal is to rotate head 90°while patient is in the supine position, nystagmus would appear in the unaffected side weaker but longer than the affected side. canal paresis has been described in one third of the patients with BPPV. Adaptation which is one of the remarkable features of BPPV in PSC is rarely seen in LSC. Rotations of 270° or 360° around the yaw axis (the so-called barbecue maneuver toward the unaffected ear are popular methods for the treatment of geotropic HC-BPPV. These maneuvers consist of sequential head turning of 90° toward the healthy side while supine. With these maneuvers, the free-floating otoconial debris migrates in the ampullofugal direction, finally entering the utricle through the nonampullated end of the horizontal canal. This kind of vertigo recovers spontaneously more rapidly and suddenly.

  17. Generalized Information Equilibrium Approaches to EEG Sleep Stage Discrimination

    Science.gov (United States)

    Smith, Jason

    2016-01-01

    Recent advances in neuroscience have raised the hypothesis that the underlying pattern of neuronal activation which results in electroencephalography (EEG) signals is via power-law distributed neuronal avalanches, while EEG signals are nonstationary. Therefore, spectral analysis of EEG may miss many properties inherent in such signals. A complete understanding of such dynamical systems requires knowledge of the underlying nonequilibrium thermodynamics. In recent work by Fielitz and Borchardt (2011, 2014), the concept of information equilibrium (IE) in information transfer processes has successfully characterized many different systems far from thermodynamic equilibrium. We utilized a publicly available database of polysomnogram EEG data from fourteen subjects with eight different one-minute tracings of sleep stage 2 and waking and an overlapping set of eleven subjects with eight different one-minute tracings of sleep stage 3. We applied principles of IE to model EEG as a system that transfers (equilibrates) information from the time domain to scalp-recorded voltages. We find that waking consciousness is readily distinguished from sleep stages 2 and 3 by several differences in mean information transfer constants. Principles of IE applied to EEG may therefore prove to be useful in the study of changes in brain function more generally. PMID:27516806

  18. Generalized Information Equilibrium Approaches to EEG Sleep Stage Discrimination

    Directory of Open Access Journals (Sweden)

    Todd Zorick

    2016-01-01

    Full Text Available Recent advances in neuroscience have raised the hypothesis that the underlying pattern of neuronal activation which results in electroencephalography (EEG signals is via power-law distributed neuronal avalanches, while EEG signals are nonstationary. Therefore, spectral analysis of EEG may miss many properties inherent in such signals. A complete understanding of such dynamical systems requires knowledge of the underlying nonequilibrium thermodynamics. In recent work by Fielitz and Borchardt (2011, 2014, the concept of information equilibrium (IE in information transfer processes has successfully characterized many different systems far from thermodynamic equilibrium. We utilized a publicly available database of polysomnogram EEG data from fourteen subjects with eight different one-minute tracings of sleep stage 2 and waking and an overlapping set of eleven subjects with eight different one-minute tracings of sleep stage 3. We applied principles of IE to model EEG as a system that transfers (equilibrates information from the time domain to scalp-recorded voltages. We find that waking consciousness is readily distinguished from sleep stages 2 and 3 by several differences in mean information transfer constants. Principles of IE applied to EEG may therefore prove to be useful in the study of changes in brain function more generally.

  19. Der benigne paroxysmale Lagerungsschwindel

    Directory of Open Access Journals (Sweden)

    Wiest G

    2004-01-01

    Full Text Available Der benigne paroxysmale Lagerungsschwindel (BPPV ist eine häufige Störung des peripheren Vestibularorgans, welche bei allen Patienten mit lageabhängigem Schwindel suspiziert werden sollte. Obwohl kurzzeitige Drehschwindelattacken als pathognomonisches Symptom gelten, weisen viele Patienten auch unsystematisierten Schwankschwindel auf, was die Diagnosestellung oft erschwert. Auslöser des BPPV sind Klziumkarbonatkristalle (Otokonien, welche sich aus der Otolithenmatrix des Utriculus lösen und in einen der drei Bogengänge gelangen. Die Diagnosestellung erfolgt mit spezifischen Provokations- bzw. Lagerungstests, um den entsprechenden Lagerungsschwindel und Nystagmus zu induzieren. Die von Semont und Epley entwickelten Befreiungsmanöver zielen darauf ab, die in den Bogengängen lokalisierten Partikel in den Utriculus zu repositionieren, wo sie keinen Drehschwindel mehr auslösen. Zur Unterscheidung des BPPV von einem zentralen Lageschwindel bzw. Nystagmus können neben der Latenz auch der Verlauf und die Dauer des Lagerungsnystagmus beitragen, von entscheidender Bedeutung in der Differentialdiagnose ist allerdings die Schlagrichtung des induzierten Nystagmus.

  20. Nihilism: a benign denial.

    Science.gov (United States)

    Skandalakis, John E; Mirilas, Petros

    2003-06-01

    Nihilism is the belief that all possible knowledge on a given topic has been amassed and codified. Ranging from benign denial to deliberate attempts at excommunication, nihilism is often encountered in the history of medicine. Eustachius, Columbus, and Sylvius strongly criticized Vesalius and defended the authority of Galen. Riolan fervently rejected Harvey's monumental work on the circulation of blood. Gross stated that no honest and sensible surgeon would ever sanction thyroidectomy. Sandstrom's discovery of the parathyroids was met with silence. Transplantation of parathyroids by Mandl was not appreciated when announced. Aristotle's dictum that the heart cannot withstand serious injury led to Paget's statement that cardiac surgery had reached the limits set by nature, which no new techniques could overcome. The first Billroth I operation was welcomed as, "Hopefully, also the last." Pancreatic surgery was opposed because the organ was of no clinical interest and was impossible for surgeons to reach. Pancreatic transplantation was rejected for many years, despite good results. When Blundell used blood transfusion for postpartum hemorrhage, critics averred that his next exploit would be radical removal of the spleen. Bassini stated that it could be risky to publish more about radical treatment of inguinal hernias. Carcinomas of the lower sigmoid and upper rectum were deemed untreatable because of their inaccessibility. Colostomy during pediatric surgery was rejected many times. Although it is difficult for the human mind to move from a familiar point of view, this propensity should not infect science, thereby impeding advancement.

  1. Benign anatomical mistakes: incidentaloma.

    Science.gov (United States)

    Mirilas, Petros; Skandalakis, J E

    2002-11-01

    The concept of the "incidentaloma," a totally asymptomatic nonfunctional tumor that is clinically and biochemically silent and discovered "incidentally" in a totally asymptomatic patient, is a by-product of the evolving diagnostic techniques of the last three decades. Various authors have used the concept for "incidental" findings during diagnostic workup for symptoms unrelated to adrenal disease, or for "incidental" adrenal tumors unrelated to symptoms that could potentially be of adrenal origin. "Incidentaloma" has been used to encompass a wide and heterogeneous spectrum of pathologic entities including adrenocortical and medullary tumors, benign or malignant lesions, hormonally active or inactive lesions, metastases, infections, granulomas, infiltrations, cysts and pseudocysts, hemorrhages, and pseudoadrenal masses. The term "incidentaloma" does not indicate whether the mass is functional, or malignant, or adrenocortical in origin. "Incidentaloma" has also appeared in the literature in reference to other endocrine organs such as pituitary, thyroid, and parathyroids, as well as the liver or kidney. We question the scientific justification for this neologism and suggest that it should be abolished. Questionable lesions should be clearly and simply described as "incidentally found."

  2. The Dynamics of EEG Entropy

    CERN Document Server

    Ignaccolo, M; Jernajczyk, W; Grigolini, P; West, B J

    2009-01-01

    EEG time series are analyzed using the diffusion entropy method. The resulting EEG entropy manifests short-time scaling, asymptotic saturation and an attenuated alpha-rhythm modulation. These properties are faithfully modeled by a phenomenological Langevin equation interpreted within a neural network context.

  3. Benign Breast Problems and Conditions

    Science.gov (United States)

    ... with a needle. Another example is a simple fibroadenoma . Simple fibroadenomas usually shrink or go away on their own. ... Cyst: A sac or pouch filled with fluid. Fibroadenoma: A type of solid, benign breast mass. Hormone: ...

  4. Laparoscopy for benign disease: robotics.

    Science.gov (United States)

    Talamini, Mark A

    2003-12-01

    Currently available robotic surgical systems appear to be particularly suited for use in benign diseases of the gastrointestinal system. Minimally invasive operations for foregut conditions, such as gastroesophageal reflux disease and achalasia, require excellent visibility and precise tissue dissection. Benign lower gastrointestinal diseases, including inflammatory bowel disease and diverticulitis, also can be approached using robotic assistance. Disadvantages include expense and the loss of tactile feedback. Early clinical results are promising.

  5. Interpreting EEG alpha activity.

    Science.gov (United States)

    Bazanova, O M; Vernon, D

    2014-07-01

    Exploring EEG alpha oscillations has generated considerable interest, in particular with regards to the role they play in cognitive, psychomotor, psycho-emotional and physiological aspects of human life. However, there is no clearly agreed upon definition of what constitutes 'alpha activity' or which of the many indices should be used to characterize it. To address these issues this review attempts to delineate EEG alpha-activity, its physical, molecular and morphological nature, and examine the following indices: (1) the individual alpha peak frequency; (2) activation magnitude, as measured by alpha amplitude suppression across the individual alpha bandwidth in response to eyes opening, and (3) alpha "auto-rhythmicity" indices: which include intra-spindle amplitude variability, spindle length and steepness. Throughout, the article offers a number of suggestions regarding the mechanism(s) of alpha activity related to inter and intra-individual variability. In addition, it provides some insights into the various psychophysiological indices of alpha activity and highlights their role in optimal functioning and behavior.

  6. Dry EEG Electrodes

    Directory of Open Access Journals (Sweden)

    M. A. Lopez-Gordo

    2014-07-01

    Full Text Available Electroencephalography (EEG emerged in the second decade of the 20th century as a technique for recording the neurophysiological response. Since then, there has been little variation in the physical principles that sustain the signal acquisition probes, otherwise called electrodes. Currently, new advances in technology have brought new unexpected fields of applications apart from the clinical, for which new aspects such as usability and gel-free operation are first order priorities. Thanks to new advances in materials and integrated electronic systems technologies, a new generation of dry electrodes has been developed to fulfill the need. In this manuscript, we review current approaches to develop dry EEG electrodes for clinical and other applications, including information about measurement methods and evaluation reports. We conclude that, although a broad and non-homogeneous diversity of approaches has been evaluated without a consensus in procedures and methodology, their performances are not far from those obtained with wet electrodes, which are considered the gold standard, thus enabling the former to be a useful tool in a variety of novel applications.

  7. INTELLIGENT EEG ANALYSIS

    Directory of Open Access Journals (Sweden)

    M. Murugesan

    2011-04-01

    Full Text Available Brain is the wonderful organ of human body. It is the agent of information collection and transformation. The neural activity of the human brain starts between the 17th and 23rd week of prenatal development. It is believed that from this early stage and throughout life electrical signals are generated by the brain function but also the status of the whole body. Understanding of neuronal functions and neurophysiologic properties of the brain function together with the mechanisms underlying the generation of signals and their recording is, however, vital for those who deal with these signals for detection, diagnosis, and treatment of brain disorders and the related diseases. This research paper concentrated only on brain tumor detection. Using minimum electrode location the brain tumor possibility is detected. This paper is separated into two parts: the First part deals with electrode location on the scalp and the second part deals with how the fuzzy logic rule based algorithm is applied for estimation of brain tumor from EEG. Basically 8 locations are identified. After acquiring the pure EEG signal Fuzzy Logic Rule is applied to predict the possibility of brain tumor.

  8. Elastography in Distinguishing Benign from Malignant Thyroid Nodules

    Directory of Open Access Journals (Sweden)

    Bulent Colakoglu

    2016-01-01

    Full Text Available Aim: The aim of this study is to test the diagnostic success of strain elastography in distinguishing benign from malignant thyroid nodules. Materials and Methods: The size, echogenicity, and halo integrity of 293 thyroid nodules and the presence of microcalcification in these nodules were evaluated on gray-scale examination. Doppler characteristics and elastography patterns were also evaluated and recorded. Nodules were classified in four categories (patterns 1-4 based on elastographic examination. Results: According to the cytopathological findings, 222 nodules were benign, and 71 nodules were malignant. The risk of a nodule to be malignant was 3.8 times increased by hypoechogenicity, 7.7 times increased by the presence of microcalcification, and 11.5 times increased by the absence of halo. On Doppler patterns, the presence of central vascularity increased the malignancy risk of a nodule by 5.8 times. According to the receiver operating characteristic analysis, patterns 3 and 4 were malignant, and patterns 1 and 2 were benign. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of elastography were 100%, 80.2%, 61.7%, 100%, and 85%, respectively. Conclusion: Strain elastography can be used as a noninvasive method in distinguishing benign from malignant thyroid nodules and in identifying the patients who would undergo surgery.

  9. Elastography in Distinguishing Benign from Malignant Thyroid Nodules

    Science.gov (United States)

    Colakoglu, Bulent; Yildirim, Duzgun; Alis, Deniz; Ucar, Gokhan; Samanci, Cesur; Ustabasioglu, Fethi Emre; Bakir, Alev; Ulusoy, Onur Levent

    2016-01-01

    Aim: The aim of this study is to test the diagnostic success of strain elastography in distinguishing benign from malignant thyroid nodules. Materials and Methods: The size, echogenicity, and halo integrity of 293 thyroid nodules and the presence of microcalcification in these nodules were evaluated on gray-scale examination. Doppler characteristics and elastography patterns were also evaluated and recorded. Nodules were classified in four categories (patterns 1–4) based on elastographic examination. Results: According to the cytopathological findings, 222 nodules were benign, and 71 nodules were malignant. The risk of a nodule to be malignant was 3.8 times increased by hypoechogenicity, 7.7 times increased by the presence of microcalcification, and 11.5 times increased by the absence of halo. On Doppler patterns, the presence of central vascularity increased the malignancy risk of a nodule by 5.8 times. According to the receiver operating characteristic analysis, patterns 3 and 4 were malignant, and patterns 1 and 2 were benign. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of elastography were 100%, 80.2%, 61.7%, 100%, and 85%, respectively. Conclusion: Strain elastography can be used as a noninvasive method in distinguishing benign from malignant thyroid nodules and in identifying the patients who would undergo surgery. PMID:28123841

  10. Benign mixed tumor of the lacrimal sac

    Directory of Open Access Journals (Sweden)

    Jong-Suk Lee

    2015-01-01

    Full Text Available Neoplasms of the lacrimal drainage system are uncommon, but potentially life-threatening and are often difficult to diagnose. Among primary lacrimal sac tumors, benign mixed tumors are extremely rare. Histologically, benign mixed tumors have been classified as a type of benign epithelial tumor. Here we report a case of benign mixed tumor of the lacrimal sac.

  11. Conducting Art Therapy Research Using Quantitative EEG Measures

    Science.gov (United States)

    Belkofer, Christopher M.; Konopka, Lukasz M.

    2008-01-01

    This study presents a modified, single subject design that measured the patterns of electrical activity of a participant's brain following an hour spent painting and drawing. Paired t tests were used to compare pre and post art-making electroencephalograph (EEG) data. The results indicated that neurobiological activity after drawing and painting…

  12. Classification of spontaneous EEG signals in migraine

    Science.gov (United States)

    Bellotti, R.; De Carlo, F.; de Tommaso, M.; Lucente, M.

    2007-08-01

    We set up a classification system able to detect patients affected by migraine without aura, through the analysis of their spontaneous EEG patterns. First, the signals are characterized by means of wavelet-based features, than a supervised neural network is used to classify the multichannel data. For the feature extraction, scale-dependent and scale-independent methods are considered with a variety of wavelet functions. Both the approaches provide very high and almost comparable classification performances. A complete separation of the two groups is obtained when the data are plotted in the plane spanned by two suitable neural outputs.

  13. Radical pancreaticoduodenectomy for benign disease.

    LENUS (Irish Health Repository)

    Kavanagh, D O

    2008-01-01

    Whipple\\'s procedure is the treatment of choice for pancreatic and periampullary malignancies. Preoperative histological confirmation of malignancy is frequently unavailable and some patients will subsequently be found to have benign disease. Here, we review our experience with Whipple\\'s procedure for patients ultimately proven to have benign disease. The medical records of all patients who underwent Whipple\\'s procedure during a 15-year period (1987-2002) were reviewed; 112 patients underwent the procedure for suspected malignancy. In eight cases, the final histology was benign (7.1%). One additional patient was known to have benign disease at resection. The mean age was 50 years (range: 30-75). The major presenting features included jaundice (five), pain (two), gastric outlet obstruction (one), and recurrent gastrointestinal haemorrhage (one). Investigations included ultrasound (eight), computerised tomography (eight), endoscopic retrograde cholangiopancreatography (seven; of these, four patients had a stent inserted and three patients had sampling for cytology), and endoscopic ultrasound (two). The pathological diagnosis included benign biliary stricture (two), chronic pancreatitis (two), choledochal cyst (one), inflammatory pseudotumour (one), cystic duodenal wall dysplasia (one), duodenal angiodysplasia (one), and granular cell neoplasm (one). There was no operative mortality. Morbidity included intra-abdominal collection (one), anastomotic leak (one), liver abscess (one), and myocardial infarction (one). All patients remain alive and well at mean follow-up of 41 months. Despite recent advances in diagnostic imaging, 8% of the patients undergoing Whipple\\'s procedure had benign disease. A range of unusual pathological entities can mimic malignancy. Accurate preoperative histological diagnosis may have allowed a less radical operation to be performed. Endoscopic ultrasound-guided fine needle aspirate (EUS-FNA) may reduce the need for Whipple\\'s operation

  14. Classifying depth of anesthesia using EEG features, a comparison.

    Science.gov (United States)

    Esmaeili, Vahid; Shamsollahi, Mohammad Bagher; Arefian, Noor Mohammad; Assareh, Amin

    2007-01-01

    Various EEG features have been used in depth of anesthesia (DOA) studies. The objective of this study was to find the excellent features or combination of them than can discriminate between different anesthesia states. Conducting a clinical study on 22 patients we could define 4 distinct anesthetic states: awake, moderate, general anesthesia, and isoelectric. We examined features that have been used in earlier studies using single-channel EEG signal processing method. The maximum accuracy (99.02%) achieved using approximate entropy as the feature. Some other features could well discriminate a particular state of anesthesia. We could completely classify the patterns by means of 3 features and Bayesian classifier.

  15. Cholesterol and benign prostate disease.

    Science.gov (United States)

    Freeman, Michael R; Solomon, Keith R

    2011-01-01

    The origins of benign prostatic diseases, such as benign prostatic hyperplasia (BPH) and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), are poorly understood. Patients suffering from benign prostatic symptoms report a substantially reduced quality of life, and the relationship between benign prostate conditions and prostate cancer is uncertain. Epidemiologic data for BPH and CP/CPPS are limited, however an apparent association between BPH symptoms and cardiovascular disease (CVD) has been consistently reported. The prostate synthesizes and stores large amounts of cholesterol and prostate tissues may be particularly sensitive to perturbations in cholesterol metabolism. Hypercholesterolemia, a major risk factor for CVD, is also a risk factor for BPH. Animal model and clinical trial findings suggest that agents that inhibit cholesterol absorption from the intestine, such as the class of compounds known as polyene macrolides, can reduce prostate gland size and improve lower urinary tract symptoms (LUTS). Observational studies indicate that cholesterol-lowering drugs reduce the risk of aggressive prostate cancer, while prostate cancer cell growth and survival pathways depend in part on cholesterol-sensitive biochemical mechanisms. Here we review the evidence that cholesterol metabolism plays a role in the incidence of benign prostate disease and we highlight possible therapeutic approaches based on this concept.

  16. Emergency EEG: study of survival EEG de urgência: taxa de sobrevivência

    Directory of Open Access Journals (Sweden)

    Moacir Alves Borges

    2010-04-01

    Full Text Available OBJECTIVE: To determine the survival rate according to the main findings of emergency electroencephalography (EEGs of patients treated in a tertiary hospital. METHOD: In this prospective study, the findings of consecutive emergency EEGs performed on inpatients in Hospital de Base in São José do Rio Preto, Brazil were correlated with survival utilizing Kaplan-Meyer survival curves. RESULTS: A total of 681 patients with an average age of 42 years old (1 day to 96 years were evaluated, of which 406 were male. The main reasons for EEGs were epileptic seizures (221 cases, hepatic encephalopathy [116 cases of which 85 (73.3% were men, p-value=0.001], status epilepticus (104 cases and impaired consciousness (78 cases. The underlying disease was confirmed in 578 (84.3% cases with 119 (17.5% having liver disease [91 (76.0% were men, p-value=0.001], 105 (15.4% suffering strokes, 67 (9.9% having metabolic disorders, 51 (7.5% central nervous system infections and 49 (7.2% epilepsy. In the three months following EEG, a survival rate of 75% was found in patients with normal, discreet slow activity or intermittent rhythmic delta activity EEGs, of 50% for those with continuous delta activity and generalized epileptiform discharges, and of 25% for those with burst-suppression, diffuse depression, and in alpha/theta-pattern coma. Death was pronounced immediately in patients with isoelectric EEGs. CONCLUSION: The main findings of EEGs, differentiated different survival rates and are thus a good prognostic tool for patients examined in emergencies.OBJETIVO: Determinar a taxa de sobrevivência (TS, segundo os principais achados de eletrencefalograma de urgência (E-EEG, dos pacientes atendidos nas emergências de hospital de alta complexidade. MÉTODO: Estudo prospectivo, por ordem de chegada, da correlação entre os achados de E-EEG, feitos nos pacientes à beira do leito, com TS, utilizando-se as curvas de sobrevidas de Kaplan Meyer no Hospital de Base de S

  17. Multifractal detrended fluctuation analysis of human EEG: preliminary investigation and comparison with the wavelet transform modulus maxima technique.

    Directory of Open Access Journals (Sweden)

    Todd Zorick

    Full Text Available Recently, many lines of investigation in neuroscience and statistical physics have converged to raise the hypothesis that the underlying pattern of neuronal activation which results in electroencephalography (EEG signals is nonlinear, with self-affine dynamics, while scalp-recorded EEG signals themselves are nonstationary. Therefore, traditional methods of EEG analysis may miss many properties inherent in such signals. Similarly, fractal analysis of EEG signals has shown scaling behaviors that may not be consistent with pure monofractal processes. In this study, we hypothesized that scalp-recorded human EEG signals may be better modeled as an underlying multifractal process. We utilized the Physionet online database, a publicly available database of human EEG signals as a standardized reference database for this study. Herein, we report the use of multifractal detrended fluctuation analysis on human EEG signals derived from waking and different sleep stages, and show evidence that supports the use of multifractal methods. Next, we compare multifractal detrended fluctuation analysis to a previously published multifractal technique, wavelet transform modulus maxima, using EEG signals from waking and sleep, and demonstrate that multifractal detrended fluctuation analysis has lower indices of variability. Finally, we report a preliminary investigation into the use of multifractal detrended fluctuation analysis as a pattern classification technique on human EEG signals from waking and different sleep stages, and demonstrate its potential utility for automatic classification of different states of consciousness. Therefore, multifractal detrended fluctuation analysis may be a useful pattern classification technique to distinguish among different states of brain function.

  18. High-resolution EEG (HR-EEG) and magnetoencephalography (MEG).

    Science.gov (United States)

    Gavaret, M; Maillard, L; Jung, J

    2015-03-01

    High-resolution EEG (HR-EEG) and magnetoencephalography (MEG) allow the recording of spontaneous or evoked electromagnetic brain activity with excellent temporal resolution. Data must be recorded with high temporal resolution (sampling rate) and high spatial resolution (number of channels). Data analyses are based on several steps with selection of electromagnetic signals, elaboration of a head model and use of algorithms in order to solve the inverse problem. Due to considerable technical advances in spatial resolution, these tools now represent real methods of ElectroMagnetic Source Imaging. HR-EEG and MEG constitute non-invasive and complementary examinations, characterized by distinct sensitivities according to the location and orientation of intracerebral generators. In the presurgical assessment of drug-resistant partial epilepsies, HR-EEG and MEG can characterize and localize interictal activities and thus the irritative zone. HR-EEG and MEG often yield significant additional data that are complementary to other presurgical investigations and particularly relevant in MRI-negative cases. Currently, the determination of the epileptogenic zone and functional brain mapping remain rather less well-validated indications. In France, in 2014, HR-EEG is now part of standard clinical investigation of epilepsy, while MEG remains a research technique.

  19. Variation in infant EEG power across social and nonsocial contexts.

    Science.gov (United States)

    St John, Ashley M; Kao, Katie; Choksi, Maitreyi; Liederman, Jacqueline; Grieve, Philip G; Tarullo, Amanda R

    2016-12-01

    To understand the infant social brain, it is critical to observe functional neural activation during social interaction. Yet many infant electroencephalography (EEG) studies on socioemotional development have recorded neural activity only during a baseline state. This study investigated how infant EEG power (4-6Hz and 6-9Hz) varies across social and nonsocial contexts. EEG was recorded in 12-month-olds across controlled conditions to disentangle the neural bases of social interactions. Four conditions-nonsocial, joint attention, language-only, and social engagement-were designed to tease apart how different environmental inputs relate to infant EEG power. We analyzed EEG power in frontal, central, temporal, and parietal regions. During the joint attention condition compared with the other conditions, 4-6Hz frontal, central, and parietal power was lowest, indexing greater neural activation. There was lower 4-6Hz and 6-9Hz power in the temporal region in both the joint attention and social engagement conditions compared with the nonsocial condition. In 6-9Hz, the pattern was consistent with 4-6Hz findings for the frontal region such that 6-9Hz frontal power was lower, indexing greater neural activation, in the joint attention condition compared with the nonsocial condition. There were no differences between conditions in central and parietal regions in 6-9Hz. Findings highlight the methodological importance of recording functional brain activity in multiple controlled contexts to explicate the neural bases of the infant social brain.

  20. Modulation of EEG Theta Band Signal Complexity by Music Therapy

    Science.gov (United States)

    Bhattacharya, Joydeep; Lee, Eun-Jeong

    The primary goal of this study was to investigate the impact of monochord (MC) sounds, a type of archaic sounds used in music therapy, on the neural complexity of EEG signals obtained from patients undergoing chemotherapy. The secondary goal was to compare the EEG signal complexity values for monochords with those for progressive muscle relaxation (PMR), an alternative therapy for relaxation. Forty cancer patients were randomly allocated to one of the two relaxation groups, MC and PMR, over a period of six months; continuous EEG signals were recorded during the first and last sessions. EEG signals were analyzed by applying signal mode complexity, a measure of complexity of neuronal oscillations. Across sessions, both groups showed a modulation of complexity of beta-2 band (20-29Hz) at midfrontal regions, but only MC group showed a modulation of complexity of theta band (3.5-7.5Hz) at posterior regions. Therefore, the neuronal complexity patterns showed different changes in EEG frequency band specific complexity resulting in two different types of interventions. Moreover, the different neural responses to listening to monochords and PMR were observed after regular relaxation interventions over a short time span.

  1. [Correlation between EEG and neuroimaging].

    Science.gov (United States)

    Tobimatsu, Shozo

    2012-01-01

    The present state of knowledge of physiological mechanisms underlying nonepileptiform EEG abnormalities is reviewed to clarify the correlation between EEG and neuroimaging. Focal and widespread slow waves, background abnormalities, and bursts of rhythmic slow activity are discussed. EEG phenomena were correlated with lesion size, location, type (white matter vs. gray matter, high density vs. low density), and mass effect. Clinical and experimental accumulated over the past five decades suggest that polymorphic slow activity is generated in cerebral cortex by layers of pyramidal cells and is probably due to partial deafferentation from subcortical areas. Unilateral background activity changes are probably thalamic dysfunction, and bilateral paroxysmal slow activity is due to abnormal thalamocortical circuits combined with cortical pathology. Paroxysmal discharges indicate the presence of epilepsy with possible brain lesion(s). The EEG is a functional test and provides us complementary information to neuroimaging studies.

  2. Environmentally Benign Stab Detonators

    Energy Technology Data Exchange (ETDEWEB)

    Gash, A E

    2006-07-07

    The coupling of energetic metallic multilayers (a.k.a. flash metal) with energetic sol-gel synthesis and processing is an entirely new approach to forming energetic devices for several DoD and DOE needs. They are also practical and commercially viable manufacturing techniques. Improved occupational safety and health, performance, reliability, reproducibility, and environmentally acceptable processing can be achieved using these methodologies and materials. The development and fielding of this technology will enhance mission readiness and reduce the costs, environmental risks and the necessity of resolving environmental concerns related to maintaining military readiness while simultaneously enhancing safety and health. Without sacrificing current performance, we will formulate new impact initiated device (IID) compositions to replace materials from the current composition that pose significant environmental, health, and safety problems associated with functions such as synthesis, material receipt, storage, handling, processing into the composition, reaction products from testing, and safe disposal. To do this, we will advance the use of nanocomposite preparation via the use of multilayer flash metal and sol-gel technologies and apply it to new small IIDs. This work will also serve to demonstrate that these technologies and resultant materials are relevant and practical to a variety of energetic needs of DoD and DOE. The goal will be to produce an IID whose composition is acceptable by OSHA, EPA, the Clean Air Act, Clean Water Act, Resource Recovery Act, etc. standards, without sacrificing current performance. The development of environmentally benign stab detonators and igniters will result in the removal of hazardous and toxic components associated with their manufacturing, handling, and use. This will lead to improved worker safety during manufacturing as well as reduced exposure of Service personnel during their storage and or use in operations. The

  3. Prognostic value of electroencephalography (EEG) for brain injury after cardiopulmonary resuscitation.

    Science.gov (United States)

    Feng, Guibo; Jiang, Guohui; Li, Zhiwei; Wang, Xuefeng

    2016-06-01

    Cardiac arrest (CA) patients can experience neurological sequelae or even death after successful cardiopulmonary resuscitation (CPR) due to cerebral hypoxia- and ischemia-reperfusion-mediated brain injury. Thus, it is important to perform early prognostic evaluations in CA patients. Electroencephalography (EEG) is an important tool for determining the prognosis of hypoxic-ischemic encephalopathy due to its real-time measurement of brain function. Based on EEG, burst suppression, a burst suppression ratio >0.239, periodic discharges, status epilepticus, stimulus-induced rhythmic, periodic or ictal discharges, non-reactive EEG, and the BIS value based on quantitative EEG may be associated with the prognosis of CA after successful CPR. As measures of neural network integrity, the values of small-world characteristics of the neural network derived from EEG patterns have potential applications.

  4. Design of environmentally benign processes

    DEFF Research Database (Denmark)

    Hostrup, Martin; Harper, Peter Mathias; Gani, Rafiqul

    1999-01-01

    This paper presents a hybrid method for design of environmentally benign processes. The hybrid method integrates mathematical modelling with heuristic approaches to solving the optimisation problems related to separation process synthesis and solvent design and selection. A structured method...... of solution, which employs thermodynamic insights to reduce the complexity and size of the mathematical problem by eliminating redundant alternatives, has been developed for the hybrid method. Separation process synthesis and design problems related to the removal of a chemical species from process streams...... mixture and the second example involves the determination of environmentally benign substitute solvents for removal of a chemical species from wastewater. (C) 1999 Elsevier Science Ltd. All rights reserved....

  5. Multicystic Benign Mesothelioma Complicating Pregnancy.

    Science.gov (United States)

    Tamhankar, V A

    2015-01-01

    Multicystic benign mesothelioma (MBM) is a rare peritoneal pathology typically affecting women in reproductive age. Though MBM is considered benign, these lesions are prone to recurrence and their growth could be modulated by the presence of oestrogen receptors. Acute presentation of MBM is still very rare in pregnancy and management options are not established. We describe a case of MBM presenting in early pregnancy with acute pain. This was successfully treated with surgical resection. Pregnancy continued uneventfully to term and no evidence of recurrent MBM was found at Caesarean section.

  6. Multicystic Benign Mesothelioma Complicating Pregnancy

    Directory of Open Access Journals (Sweden)

    V. A. Tamhankar

    2015-01-01

    Full Text Available Multicystic benign mesothelioma (MBM is a rare peritoneal pathology typically affecting women in reproductive age. Though MBM is considered benign, these lesions are prone to recurrence and their growth could be modulated by the presence of oestrogen receptors. Acute presentation of MBM is still very rare in pregnancy and management options are not established. We describe a case of MBM presenting in early pregnancy with acute pain. This was successfully treated with surgical resection. Pregnancy continued uneventfully to term and no evidence of recurrent MBM was found at Caesarean section.

  7. Altered Resting-State EEG Source Functional Connectivity In Schizophrenia: The Effect Of Illness Duration

    Directory of Open Access Journals (Sweden)

    Giorgio eDi Lorenzo

    2015-05-01

    Full Text Available Despite the increasing body of evidence supporting the hypothesis of schizophrenia as a disconnection syndrome, studies of resting-state EEG Source Functional Connectivity (EEG-SFC in people affected by schizophrenia are sparse. The aim of the present study was to investigate resting-state EEG-SFC in 77 stable, medicated patients with schizophrenia (SCZ compared to 78 healthy volunteers (HV. In order to study the effect of illness duration, SCZ were divided in those with a short duration of disease (SDD; n = 25 and those with a long duration of disease (LDD; n = 52. Resting-state EEG recordings in eyes closed condition were analyzed and lagged phase synchronization (LPS indices were calculated for each ROI pair in the source-space EEG data. In delta and theta bands, SCZ had greater EEG-SFC than HV; a higher theta band connectivity in frontal regions was observed in LDD compared with SDD. In the alpha band, SCZ showed lower frontal EEG-SFC compared with HV whereas no differences were found between LDD and SDD. In the beta1 band, SCZ had greater EEG-SFC compared with HVs and in the beta2 band, LDD presented lower frontal and parieto-temporal EEG-SFC compared with HV. In the gamma band, SDD had greater connectivity values compared with LDD and HV. This study suggests that resting state brain network connectivity is abnormally organized in schizophrenia, with different patterns for the different EEG frequency components and that EEG can be a powerful tool to further elucidate the complexity of such disordered connectivity.

  8. Benign concentric annular macular dystrophy

    Directory of Open Access Journals (Sweden)

    Luísa Salles de Moura Mendonça

    2015-06-01

    Full Text Available The purpose of the authors is to show clinical findings of a patient with benign concentric annular macular dystrophy, which is an unusual condition, and part of the "bull’s eye" maculopathy differential diagnosis. An ophthalmologic examination with color perception, fluorescein angiography, and ocular electrophysiology was performed.

  9. Additional value of two-channel amplitude integrated EEG recording in full-term infants with unilateral brain injury

    NARCIS (Netherlands)

    van Rooij, Linda G. M.; de Vries, Linda S.; van Huffelen, Alexander C.; Toet, Mona C.

    2010-01-01

    Background Amplitude integrated electroencephalography (aEEG) is a valuable tool for evaluating neonatal encephalopathy and identifying electrographic seizures. Objective To compare seizure activity and background pattern (BGP) between one-channel and two-channel aEEG recordings in full-term neonate

  10. Histiocytic sarcoma that mimics benign histiocytosis.

    Science.gov (United States)

    Boisseau-Garsaud, A M; Vergier, B; Beylot-Barry, M; Nastasel-Menini, F; Dubus, P; de Mascarel, A; Eghbali, H; Beylot, C

    1996-06-01

    A 28-year-old man presented with a histiocytic sarcoma of a very uncommon origin, as it had developed for several years like a benign cutaneous histiocytosis resembling generalized eruptive histiocytoma before becoming acute, with nodal and massive pulmonary involvement. Despite various chemotherapies, the patient died within 8 months. Skin biopsies showed histiocytic proliferation in the dermis and node biopsies showed histiocytic proliferation with a sinusoidal pattern. Immunohistochemical analysis, performed on paraffin-embedded sections, demonstrated strong labeling of tumoral cells for CD68 and moderate labeling for CD3 and CD4. CD30 labeling was negative. S-100 protein was positive on a Langerhans' cell reactive subpopulation. Electron microscopy confirmed the histiocytic nature of malignant cells and showed cytoplasmic inclusions such as regularly laminated bodies, dense bodies and pleomorphic inclusions. No Birbeck granules were seen. A gene rearrangement study of T-cell receptor gamma and immunoglobulin heavy chain genes showed a germline configuration. Histiocytic sarcoma is an extremely rare true histiocytic malignancy, the existence of which has been recently debated since it has often been mistaken in the past for large cell lymphomas. Such a deceptive onset as benign cutaneous histiocytosis has not been described in the literature to our knowledge.

  11. EEG in postanoxic coma: Prognostic and diagnostic value.

    Science.gov (United States)

    Hofmeijer, J; van Putten, M J A M

    2016-04-01

    Evolution of the EEG background pattern is a robust contributor to prediction of poor or good outcome of comatose patients after cardiac arrest. At 24h, persistent isoelectricity, low voltage activity, or burst-suppression with identical bursts predicts a poor outcome without false positives. Rapid recovery toward continuous patterns within 12h is strongly associated with a good neurological outcome. Predictive values are highest in the first 24h, despite the use of mild therapeutic hypothermia and sedative medication. Studies on reactivity or mismatch negativity have not included the EEG background pattern. Therefore, the additional predictive value of reactivity parameters remains unclear. Whether or not treatment of electrographic status epilepticus improves outcome is studied in the randomized multicenter Treatment of Electroencephalographic STatus epilepticus After cardiopulmonary Resuscitation (TELSTAR) trial (NCT02056236).

  12. Automatic classification of background EEG activity in healthy and sick neonates

    Science.gov (United States)

    Löfhede, Johan; Thordstein, Magnus; Löfgren, Nils; Flisberg, Anders; Rosa-Zurera, Manuel; Kjellmer, Ingemar; Lindecrantz, Kaj

    2010-02-01

    The overall aim of our research is to develop methods for a monitoring system to be used at neonatal intensive care units. When monitoring a baby, a range of different types of background activity needs to be considered. In this work, we have developed a scheme for automatic classification of background EEG activity in newborn babies. EEG from six full-term babies who were displaying a burst suppression pattern while suffering from the after-effects of asphyxia during birth was included along with EEG from 20 full-term healthy newborn babies. The signals from the healthy babies were divided into four behavioural states: active awake, quiet awake, active sleep and quiet sleep. By using a number of features extracted from the EEG together with Fisher's linear discriminant classifier we have managed to achieve 100% correct classification when separating burst suppression EEG from all four healthy EEG types and 93% true positive classification when separating quiet sleep from the other types. The other three sleep stages could not be classified. When the pathological burst suppression pattern was detected, the analysis was taken one step further and the signal was segmented into burst and suppression, allowing clinically relevant parameters such as suppression length and burst suppression ratio to be calculated. The segmentation of the burst suppression EEG works well, with a probability of error around 4%.

  13. Radioiodine therapy of benign thyroid disease; Radioiodbehandling af benign thyreoideasygdom

    Energy Technology Data Exchange (ETDEWEB)

    Krogh Rasmussen, Aa.; Jarloev, A.E.; Faber, J

    2000-01-01

    The aim of the study was to evaluate differences in the use of radioactive iodine in the treatment of benigh thyroid disease in Denmark. A questionnaire was distributed to all departments in Denmark which administer radioiodine in the treatment of benign thyroid disease (n=20). Radioiodine is used for patients with toxic nodular goitre and for patients with relapse of toxic diffuse goitre. Four departments did not use radioiodine for volume reduction in non-toxic goitre. Patient information's included very different recommendations regarding cautions in relation to radioiodine treatment. Radioiodine is widely used in the treatment of benign thyroid disease. We recommend a national standardization of the cautions in relation to radioiodine treatment. (au)

  14. Impact of the reference choice on scalp EEG connectivity estimation

    Science.gov (United States)

    Chella, Federico; Pizzella, Vittorio; Zappasodi, Filippo; Marzetti, Laura

    2016-06-01

    Objective. Several scalp EEG functional connectivity studies, mostly clinical, seem to overlook the reference electrode impact. The subsequent interpretation of brain connectivity is thus often biased by the choice of a non-neutral reference. This study aims at systematically investigating these effects. Approach. As EEG reference, we examined the vertex electrode (Cz), the digitally linked mastoids (DLM), the average reference (AVE), and the reference electrode standardization technique (REST). As a connectivity metric, we used the imaginary part of the coherency. We tested simulated and real data (eyes-open resting state) by evaluating the influence of electrode density, the effect of head model accuracy in the REST transformation, and the impact on the characterization of the topology of functional networks from graph analysis. Main results. Simulations demonstrated that REST significantly reduced the distortion of connectivity patterns when compared to AVE, Cz, and DLM references. Moreover, the availability of high-density EEG systems and an accurate knowledge of the head model are crucial elements to improve REST performance, with the individual realistic head model being preferable to the standard realistic head model. For real data, a systematic change of the spatial pattern of functional connectivity depending on the chosen reference was also observed. The distortion of connectivity patterns was larger for the Cz reference, and progressively decreased when using the DLM, the AVE, and the REST. Strikingly, we also showed that network attributes derived from graph analysis, i.e. node degree and local efficiency, are significantly influenced by the EEG reference choice. Significance. Overall, this study highlights that significant differences arise in scalp EEG functional connectivity and graph network properties, in dependence on the chosen reference. We hope that our study will convey the message that caution should be used when interpreting and comparing

  15. Benign occipital epilepsy of childhood: Panayiotopoulos syndrome in a 3 year old child

    Directory of Open Access Journals (Sweden)

    Menon Narayanankutty Sunilkumar , Vadakut Krishnan Parvathy

    2014-11-01

    Full Text Available Panayiotopoulos syndrome (PS is a relatively frequent and benign epileptic syndrome seen in children in the age group of 3-6 years and is characterised by predominantly autonomic symptoms and/or simple motor focal seizures followed or not by impairment of consciousness. Although multifocal spikes with high amplitude sharp-slow wave complexes at various locations can be present in the EEG, interictal electroencephalogram (EEG in children with this particular type of epilepsy characteristically shows occipital spikes. This syndrome has known to be a masquerader and can imitate gastroenteritis, encephalitis, syncope, migraine, sleep disorders or metabolic diseases. In the absence of thorough knowledge of types of benign epilepsy syndromes and their various clinical presentations, epilepsy such as PS can be easily missed. The peculiar aspects of this type of epilepsy in children should be known not only by paediatricians but also by general doctors because a correct diagnosis would avoid aggressive interventions and concerns on account of its benign outcome. In this case study, we report a case of PS in a 3 year old child.

  16. Continuous EEG in Critically Ill Children

    Directory of Open Access Journals (Sweden)

    Jonathan E Kurz

    2015-03-01

    Full Text Available Investigators from the Critical Care Continuous EEG Task Force of the American Clinical Neurophysiology Society reported a consensus statement on indications for the use of critical care continuous electroencephalographic monitoring (ccEEG in adults and children.

  17. EEG Signal Denoising and Feature Extraction Using Wavelet Transform in Brain Computer Interface

    Institute of Scientific and Technical Information of China (English)

    WU Ting; YAN Guo-zheng; YANG Bang-hua; SUN Hong

    2007-01-01

    Electroencephalogram (EEG) signal preprocessing is one of the most important techniques in brain computer interface (BCI). The target is to increase signal-to-noise ratio and make it more favorable for feature extraction and pattern recognition. Wavelet transform is a method of multi-resolution time-frequency analysis, it can decompose the mixed signals which consist of different frequencies into different frequency band. EEG signal is analyzed and denoised using wavelet transform. Moreover, wavelet transform can be used for EEG feature extraction. The energies of specific sub-bands and corresponding decomposition coefficients which have maximal separability according to the Fisher distance criterion are selected as features. The eigenvector for classification is obtained by combining the effective features from different channels. The performance is evaluated by separability and pattern recognition accuracy using the data set of BCI 2003 Competition, the final classification results have proved the effectiveness of this technology for EEG denoising and feature extraction.

  18. Gender differences in hemispheric organization during divergent thinking: an EEG investigation in human subjects.

    Science.gov (United States)

    Razumnikova, Olga M

    2004-05-27

    This study examined the gender-related differences in EEG patterns during the experimental condition of divergent thinking. The EEG of 36 males and 27 females was recorded from 16 scalp electrodes in rest and while students were solving a creative problem. The spectral power density along with EEG coherence estimates were analyzed in each of the six frequency bands in the 4-30 Hz range. Gender-related differences in the EEG patterns were found during successful divergent thinking. Creative men were characterized by massive increases of amplitude and interhemispheric coherence in the beta2 whereas creative women showed more local increases of the beta2 power and coherence. On the contrary, the task-induced desynchronization of the alpha1 rhythm in creative women was topographically more expanded as compared with men who demonstrated greater interhemispheric coherence than women did. Our results propose a different hemispheric organization in men and women during creative thinking.

  19. Analysis of Age Dependent Effects of Heat Stress on EEG Frequency Components in Rats

    Institute of Scientific and Technical Information of China (English)

    RAKESH KUMAR SINHA

    2009-01-01

    Objective To demonstrate changes in different frequencies of cerebral electrical activity or electroencephalogram (EEG) following exposure to high environmental heat in three different age groups of freely moving rats. Methods Rats were divided into three groups (i) acute heat stress - subjected to a single exposure for four hours at 38 ℃; (ii) chronic heat stress -exposed for 21 days daily for one hour at 38 ℃, and (iii) handling control groups. The digital polygraphic sleep-EEG recordings were performed just after the heat exposure from acute stressed rats and on 22nd day from chronic stressed rats by simultaneous recording of cortical EEG EOG (electrooculogram), and EMG (electromyogram). Further, power spectrum analyses were performed to analyze the effects of heat stress. Results The frequency analysis of EEG signals following exposure to high environmental heat revealed that in all three age groups of rats, changes in higher frequency components (β2) were significant in all sleep-wake states following both acute and chronic heat stress conditions. After exposure to acute heat, significant changes in EEG frequencies with respect to their control groups were observed, which were reversed partly or fully in four hours of EEG recording. On the other hand, due to repetitive chronic exposure to hot environment, adaptive and long-term changes in EEG frequency patterns were observed. Conclusion The present study has exhibited that the cortical EEG is sensitive to environmental heat and alterations in EEG frequencies in different sleep-wake states due to heat stress can be differentiated efficiently by EEG power spectrum analysis.

  20. Interhemispheric synchrony in the neonatal EEG revisited: Activation Synchrony Index as a promising classifier

    Directory of Open Access Journals (Sweden)

    Ninah eKoolen

    2014-12-01

    Full Text Available A key feature of normal neonatal EEG at term age is interhemispheric synchrony (IHS, which refers to the temporal co-incidence of bursting across hemispheres during trace alternant EEG activity. The assessment of IHS in both clinical and scientific work relies on visual, qualitative EEG assessment without clearly quantifiable definitions. A quantitative measure, activation synchrony index (ASI, was recently shown to perform well as compared to visual assessments. The present study set out to test whether IHS is stable enough for clinical use, and whether it could be an objective feature of EEG normality.We analyzed 31 neonatal EEG recordings that had been clinically classified as normal (n=14 or abnormal (n=17 using holistic, conventional visual criteria including amplitude, focal differences, qualitative synchrony, and focal abnormalities. We selected 20-minute epochs of discontinuous background pattern. ASI values were computed separately for different channel pair combinations and window lengths to define the optimal ASI intraindividual stability. Finally, ROC curves were computed to find trade-offs related to compromised data lengths, a common challenge in neonatal EEG studies.Using the average of four consecutive 2.5-minute epochs in the centro-occipital bipolar derivations gave ASI estimates that very accurately distinguished babies clinically classified as normal vs. abnormal. It was even possible to draw a cut-off limit (ASI~3.6 which correctly classified the EEGs in 97% of all cases. Finally, we showed that compromising the length of EEG segments from 20 minutes to 5 minutes leads to increased variability in ASI-based classification.Our findings support the prior literature that IHS is an important feature of normal neonatal brain function. We show that ASI may provide diagnostic value even at individual level, which strongly supports its use in prospective clinical studies on neonatal EEG as well as in the feature set of upcoming EEG

  1. Interhemispheric synchrony in the neonatal EEG revisited: activation synchrony index as a promising classifier.

    Science.gov (United States)

    Koolen, Ninah; Dereymaeker, Anneleen; Räsänen, Okko; Jansen, Katrien; Vervisch, Jan; Matic, Vladimir; De Vos, Maarten; Van Huffel, Sabine; Naulaers, Gunnar; Vanhatalo, Sampsa

    2014-01-01

    A key feature of normal neonatal EEG at term age is interhemispheric synchrony (IHS), which refers to the temporal co-incidence of bursting across hemispheres during trace alternant EEG activity. The assessment of IHS in both clinical and scientific work relies on visual, qualitative EEG assessment without clearly quantifiable definitions. A quantitative measure, activation synchrony index (ASI), was recently shown to perform well as compared to visual assessments. The present study was set out to test whether IHS is stable enough for clinical use, and whether it could be an objective feature of EEG normality. We analyzed 31 neonatal EEG recordings that had been clinically classified as normal (n = 14) or abnormal (n = 17) using holistic, conventional visual criteria including amplitude, focal differences, qualitative synchrony, and focal abnormalities. We selected 20-min epochs of discontinuous background pattern. ASI values were computed separately for different channel pair combinations and window lengths to define them for the optimal ASI intraindividual stability. Finally, ROC curves were computed to find trade-offs related to compromised data lengths, a common challenge in neonatal EEG studies. Using the average of four consecutive 2.5-min epochs in the centro-occipital bipolar derivations gave ASI estimates that very accurately distinguished babies clinically classified as normal vs. abnormal. It was even possible to draw a cut-off limit (ASI~3.6) which correctly classified the EEGs in 97% of all cases. Finally, we showed that compromising the length of EEG segments from 20 to 5 min leads to increased variability in ASI-based classification. Our findings support the prior literature that IHS is an important feature of normal neonatal brain function. We show that ASI may provide diagnostic value even at individual level, which strongly supports its use in prospective clinical studies on neonatal EEG as well as in the feature set of upcoming EEG classifiers.

  2. Engagement Assessment Using EEG Signals

    Science.gov (United States)

    Li, Feng; Li, Jiang; McKenzie, Frederic; Zhang, Guangfan; Wang, Wei; Pepe, Aaron; Xu, Roger; Schnell, Thomas; Anderson, Nick; Heitkamp, Dean

    2012-01-01

    In this paper, we present methods to analyze and improve an EEG-based engagement assessment approach, consisting of data preprocessing, feature extraction and engagement state classification. During data preprocessing, spikes, baseline drift and saturation caused by recording devices in EEG signals are identified and eliminated, and a wavelet based method is utilized to remove ocular and muscular artifacts in the EEG recordings. In feature extraction, power spectrum densities with 1 Hz bin are calculated as features, and these features are analyzed using the Fisher score and the one way ANOVA method. In the classification step, a committee classifier is trained based on the extracted features to assess engagement status. Finally, experiment results showed that there exist significant differences in the extracted features among different subjects, and we have implemented a feature normalization procedure to mitigate the differences and significantly improved the engagement assessment performance.

  3. EEG signal analysis: a survey.

    Science.gov (United States)

    Subha, D Puthankattil; Joseph, Paul K; Acharya U, Rajendra; Lim, Choo Min

    2010-04-01

    The EEG (Electroencephalogram) signal indicates the electrical activity of the brain. They are highly random in nature and may contain useful information about the brain state. However, it is very difficult to get useful information from these signals directly in the time domain just by observing them. They are basically non-linear and nonstationary in nature. Hence, important features can be extracted for the diagnosis of different diseases using advanced signal processing techniques. In this paper the effect of different events on the EEG signal, and different signal processing methods used to extract the hidden information from the signal are discussed in detail. Linear, Frequency domain, time - frequency and non-linear techniques like correlation dimension (CD), largest Lyapunov exponent (LLE), Hurst exponent (H), different entropies, fractal dimension(FD), Higher Order Spectra (HOS), phase space plots and recurrence plots are discussed in detail using a typical normal EEG signal.

  4. Complex dynamics of epileptic EEG.

    Science.gov (United States)

    Kannathal, N; Puthusserypady, Sadasivan K; Choo Min, Lim

    2004-01-01

    Electroencephalogram (EEG) - the recorded representation of electrical activity of the brain contain useful information about the state of the brain. Recent studies indicate that nonlinear methods can extract valuable information from neuronal dynamics. We compare the dynamical properties of EEG signals of healthy subjects with epileptic subjects using nonlinear time series analysis techniques. Chaotic invariants like correlation dimension (D2) , largest Lyapunov exponent (lambda1), Hurst exponent (H) and Kolmogorov entropy (K) are used to characterize the signal. Our study showed clear differences in dynamical properties of brain electrical activity of the normal and epileptic subjects with a confidence level of more than 90%. Furthermore to support this claim fractal dimension (FD) analysis is performed. The results indicate reduction in value of FD for epileptic EEG indicating reduction in system complexity.

  5. EEG and MEG: relevance to neuroscience

    NARCIS (Netherlands)

    Lopes da Silva, F.

    2013-01-01

    To understand dynamic cognitive processes, the high time resolution of EEG/MEG is invaluable. EEG/MEG signals can play an important role in providing measures of functional and effective connectivity in the brain. After a brief description of the foundations and basic methodological aspects of EEG/M

  6. Benign chondroblastoma - malignant radiological appearances

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, K.; Treugut, H.; Mueller, G.E.

    1980-04-01

    The very rare benign chondroblastoma occasionally invades soft tissues and may grow beyond the epiphysis into the metaphysis. In the present case such a tumour did not show the typical radiological appearances, but presented malignant features both on plain films and on the angiogram. The importance of biopsy of tumours which cannot be identified with certainty must be stressed before radical surgery is carried out.

  7. Detection of Epilepsy from EEG Signal during Seizure Using Entropy-Based Fuzzy c-Means

    Directory of Open Access Journals (Sweden)

    Tahir Ahmad

    2012-09-01

    Full Text Available One of the major roles of Electrocephalography (EEG is an aid to diagnose epilepsy. Abnormal patterns such as spikes, sharp wave complexes can be seen. Our main interest is to extract information about the dynamics from a few observations of this record signal. In this study, the entropy-based fuzzy c-Means is used to cluster EEG signal of patients during an epileptic seizure.We obtained signatures of general epilepsy by superimposing results of the method.

  8. Subject position affects EEG magnitudes.

    Science.gov (United States)

    Rice, Justin K; Rorden, Christopher; Little, Jessica S; Parra, Lucas C

    2013-01-01

    EEG (electroencephalography) has been used for decades in thousands of research studies and is today a routine clinical tool despite the small magnitude of measured scalp potentials. It is widely accepted that the currents originating in the brain are strongly influenced by the high resistivity of skull bone, but it is less well known that the thin layer of CSF (cerebrospinal fluid) has perhaps an even more important effect on EEG scalp magnitude by spatially blurring the signals. Here it is shown that brain shift and the resulting small changes in CSF layer thickness, induced by changing the subject's position, have a significant effect on EEG signal magnitudes in several standard visual paradigms. For spatially incoherent high-frequency activity the effect produced by switching from prone to supine can be dramatic, increasing occipital signal power by several times for some subjects (on average 80%). MRI measurements showed that the occipital CSF layer between the brain and skull decreases by approximately 30% in thickness when a subject moves from prone to supine position. A multiple dipole model demonstrated that this can indeed lead to occipital EEG signal power increases in the same direction and order of magnitude as those observed here. These results suggest that future EEG studies should control for subjects' posture, and that some studies may consider placing their subjects into the most favorable position for the experiment. These findings also imply that special consideration should be given to EEG measurements from subjects with brain atrophy due to normal aging or neurodegenerative diseases, since the resulting increase in CSF layer thickness could profoundly decrease scalp potential measurements.

  9. Prognostic value of EEG in different etiological types of coma.

    Science.gov (United States)

    Khaburzania, M; Beridze, M

    2013-06-01

    Study aimed at evaluation of prognostic value of standard EEG in different etiology of coma and the influence of etiological factor on the EEG patterns and coma outcome. Totally 175 coma patients were investigated. Patients were evaluated by Glasgow Coma Scale (GCS), clinically and by 16 channel electroencephalography. Auditory evoked potentials studied by EEG -regime for evoked potentials in patients with vegetative state (VS). Patients divided in 8 groups according to coma etiology. All patients were studied for photoreaction, brainstem reflexes, localization of sound and pain, length of coma state and outcome. Brain injury visualized by conventional CT. Outcome defined as death, VS, recovery with disability and without disability. Disability was rated by Disability Rating Scale (DRS). Recovered patients assessed by Mini Mental State Examination (MMSE) scale. Statistics performed by SPSS-11.0. From 175 coma patients 55 patients died, 23 patients found in VS, 97 patients recovered with and without disability. In all etiological groups of coma the background EEG patterns were established. Correspondence analysis of all investigated factors revealed that sound localization had the significant association with EEG delta and theta rhythms and with recovery from coma state (Chi-sqr. =31.10493; p= 0.000001). Among 23 VS patients 9 patients had the signs of MCS and showed the long latency waves (p300) after binaural stimulation. The high amplitude theta frequencies in frontal and temporal lobes significantly correlated with prolongation of latency of cognitive evoked potentials (r=+0.47; pcoma outcome only in hemorrhagic and traumatic coma (chi-sqr.=12.95; pcoma outcome. Low amplitude decreased power delta and theta frequencies correlated with SND in survived coma patients (r=+0.21; pcoma patients with a high probability to recover as well as those patients, who are at high risk of SND in case of recovery from coma state.

  10. Surrogate data modeling the relationship between high frequency amplitudes and Higuchi fractal dimension of EEG signals in anesthetized rats.

    Science.gov (United States)

    Spasic, Sladjana; Kalauzi, Aleksandar; Kesic, Srdjan; Obradovic, Milica; Saponjic, Jasna

    2011-11-21

    We used spectral analysis and Higuchi fractal dimension (FD) to correlate the EEG spectral characteristics of the sensorimotor cortex, hippocampus, and pons with their corresponding EEG signal complexities in anesthetized rats. We have explored the quantitative relationship between the mean FDs and EEG wide range high frequency (8-50 Hz) activity during ketamine/xylazine versus nembutal anesthesia at surgical plane. Using FD we detected distinct inter-structure complexity pattern and uncovered for the first time that the polygraphically and behaviorally defined anesthetized state at surgical plane as equal during experiment in two anesthetic regimens, is not the same with respect to the degree of neuronal activity (degree of generalized neuronal inhibition achieved) at different brain levels. Using the correlation of certain brain structure EEG spectral characteristics with their corresponding FDs, and the surrogate data modeling, we determined what particular frequency band contributes to EEG complexities in ketamine/xylazine versus nembutal anesthesia. In this study we have shown that the quantitative relationship between higher frequency EEG amplitude and EEG complexity is the best-modeled by surrogate data as a 3rd order polynomial. On the base of our EEG amplitude/EEG complexity relationship model, and the evidenced spectral differences in ketamine versus nembutal anesthesia we have proved that higher amplitudes of sigma, beta, and gamma frequency in ketamine anesthesia yields to higher FDs.

  11. 左右手运动想象脑电模式识别研究%Study of Discrimination between Left and Right Hand Movements Imagery Event-Related EEG Pattern

    Institute of Scientific and Technical Information of China (English)

    刘成; 何可人; 周天彤; 邹凌

    2013-01-01

    Recently, accurate classification of imaginary left and right hand movemetns of EEG is an important issue in brainOcomputer interface (BCD. Based on EEG data of 3 subjects which collected by -American EGI 640 -channel EEG colletion system, firstly, the effective de-noising processing to collected data by the independent component analysis method is carried out. Secondly, discrete wavelet transform method is used to decompose the average power of the channel C3/C4 in left and right hand movements imagery. The reconstructed signal of approximation coefficient A6 on the sixth level is selected to build up feature signal. Finally, to classify the feature signal respectively by Fisher Linear Discriminant Analysis (FL-DA), Support Vector Machines (SVM) and Extreme Learning Machine (ELM) methods. The classification results show that the average classification rate of -ELM is higher than that of FLDA and SVM, which can achieve 92%. The running speed of ELM is also faster than the other two methods.%如何提高左右手运动想象脑电信号的分类率是脑机接口研究领域的一个热点话题.基于美国EGI64导脑电采集系统得到3名健康被试的脑电数据,首先,采用独立成分分析(Independent Component Analysis,ICA)对采集的数据进行去噪处理;然后,利用离散小波变换方法对分解C3/C4处的EEG平均功率信号,选用尺度6上逼近系数A6的重构信号作为脑电特征信号;最后,用Fisher线性判别分析法(Fisher Linear Discriminant Analysis,FLDA)、支持向量机方法(Support Vector Machines,SVM)和极限学习机分类方法(Extreme Learning Machine,ELM)分别对特征信号进行分类.分类结果表明:极限学习机分类方法得出的平均分类率要高于Fisher方法与SVM方法的平均分类率,可以达到92%,而且运行速度也高于另两种分类算法.

  12. Classification of EEG Signals using adaptive weighted distance nearest neighbor algorithm

    Directory of Open Access Journals (Sweden)

    E. Parvinnia

    2014-01-01

    Full Text Available Electroencephalogram (EEG signals are often used to diagnose diseases such as seizure, alzheimer, and schizophrenia. One main problem with the recorded EEG samples is that they are not equally reliable due to the artifacts at the time of recording. EEG signal classification algorithms should have a mechanism to handle this issue. It seems that using adaptive classifiers can be useful for the biological signals such as EEG. In this paper, a general adaptive method named weighted distance nearest neighbor (WDNN is applied for EEG signal classification to tackle this problem. This classification algorithm assigns a weight to each training sample to control its influence in classifying test samples. The weights of training samples are used to find the nearest neighbor of an input query pattern. To assess the performance of this scheme, EEG signals of thirteen schizophrenic patients and eighteen normal subjects are analyzed for the classification of these two groups. Several features including, fractal dimension, band power and autoregressive (AR model are extracted from EEG signals. The classification results are evaluated using Leave one (subject out cross validation for reliable estimation. The results indicate that combination of WDNN and selected features can significantly outperform the basic nearest-neighbor and the other methods proposed in the past for the classification of these two groups. Therefore, this method can be a complementary tool for specialists to distinguish schizophrenia disorder.

  13. Nonlinear dynamics and quantitative EEG analysis.

    Science.gov (United States)

    Jansen, B H

    1996-01-01

    Quantitative, computerized electroencephalogram (EEG) analysis appears to be based on a phenomenological approach to EEG interpretation, and is primarily rooted in linear systems theory. A fundamentally different approach to computerized EEG analysis, however, is making its way into the laboratories. The basic idea, inspired by recent advances in the area of nonlinear dynamics and chaos theory, is to view an EEG as the output of a deterministic system of relatively simple complexity, but containing nonlinearities. This suggests that studying the geometrical dynamics of EEGs, and the development of neurophysiologically realistic models of EEG generation may produce more successful automated EEG analysis techniques than the classical, stochastic methods. A review of the fundamentals of chaos theory is provided. Evidence supporting the nonlinear dynamics paradigm to EEG interpretation is presented, and the kind of new information that can be extracted from the EEG is discussed. A case is made that a nonlinear dynamic systems viewpoint to EEG generation will profoundly affect the way EEG interpretation is currently done.

  14. EEG Findings in Burnout Patients

    NARCIS (Netherlands)

    Luijtelaar, E.L.J.M. van; Verbraak, M.J.P.M.; Bunt, P.M. van den; Keijsers, G.P.J.; Arns, M.W.

    2010-01-01

    The concept of burnout remains enigmatic since it is only determined by behavioral characteristics. Moreover, the differential diagnosis with depression and chronic fatigue syndrome is difficult. EEG-related variables in 13 patients diagnosed with burnout syndrome were compared with 13 healthy compa

  15. Predictive value of sequential electroencephalogram (EEG) in neonates with seizures and its relation to neurological outcome.

    Science.gov (United States)

    Khan, Richard Lester; Nunes, Magda Lahorgue; Garcias da Silva, Luis Fernando; da Costa, Jaderson Costa

    2008-02-01

    The aim of this study was to evaluate the relationship of sequential neonatal electroencephalography (EEG) and neurological outcome in neonates with seizures to identify polysomnographic features predictive of outcome. Sequential EEGs recordings of 58 neonates that belonged to 2 historical cohorts of newborns with seizures from the same neonatal intensive care unit and who had follow-up at the Neurodevelopment Clinic of the Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS) in Porto Alegre, Brazil, were analyzed and classified into 4 groups: normal-normal, abnormal-normal, abnormal-abnormal, normal-abnormal. In patients with more than 2 recordings, during the neonatal period, the first EEG was compared with the following more abnormal. A total of 58 pairs of 2 sequential EEGs were analyzed. Considering the first EEG, a statistically significant difference was observed between the relationship of the result of this exam, if it was abnormal, with developmental delay (P = .030) and postnatal death (P = .030). Abnormal background activity was also related to neurodevelopment delay (P = .041). EEG sequences abnormal-abnormal and normal-abnormal significantly correlated to the outcome epilepsy ( P = .015). Abnormal sequential background activity was associated with neurodevelopment delay (P = .006) and epilepsy (P = .041). The burst suppression pattern when present in any EEG correlated with epilepsy (P = .013) and postnatal death (P = .034). Sequential abnormal background patterns in the first and second EEG increased the risk for epilepsy (relative risk [RR] = 1.8; 95% confidence interval [CI] = 1.03-3.0) and neurodevelopment delay (RR = 2.20; 95% CI = 1.3-3.0). Abnormal background activity only in the second electroencephalogram increased the risk for neurodevelopment delay (RR = 2.20; 95% CI = 1.3-3.0). All the neonates (n = 33) with seizures related to probable hypoxic ischemic encephalopathy had abnormalities in the first EEG (P

  16. PyEEG: an open source Python module for EEG/MEG feature extraction.

    Science.gov (United States)

    Bao, Forrest Sheng; Liu, Xin; Zhang, Christina

    2011-01-01

    Computer-aided diagnosis of neural diseases from EEG signals (or other physiological signals that can be treated as time series, e.g., MEG) is an emerging field that has gained much attention in past years. Extracting features is a key component in the analysis of EEG signals. In our previous works, we have implemented many EEG feature extraction functions in the Python programming language. As Python is gaining more ground in scientific computing, an open source Python module for extracting EEG features has the potential to save much time for computational neuroscientists. In this paper, we introduce PyEEG, an open source Python module for EEG feature extraction.

  17. Radiological and histopathological study of benign tumors of the mandible

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Seon Young; Baek, Seung Yon; Choi, Kyung Hee; Suh, Jeung Soo; Rhee, Chung Sik; Kim, Hee Seup [Ewha Womans University College of Medicine, Seoul (Korea, Republic of)

    1984-06-15

    Benign tumors of the mandible are uncommon lesions. That were classified into odontogenic tumors and nonodontogenic tumors. Author reviewed the radiological evaluation and pathological microscopic finding from 33 benign tumors of the mandible that were confirmed by the biopsy during last 10 years in Dental Clinics, Ewha Womans University Hospital and Seoul National University Dental Hospital. Following results were obtained; 1. Benign tumors of the mandible were classified into odontogenic (66.7%) and non-odontogenic tumors (33.3%). 2. The range of the age distribution was between 6 years and 67 years old. The commonest age group was the second decade (39.4%). 3. There was no difference to sex distribution. 4. The most frequent location was the body of the mandible (42.4%). 5. Radiographic findings were relatively characteristic in odontogenic tumors rather than non-odontogenic tumors. 1) Radiolucent cystic lesions-ameloblastoma, odontogenic myxoma, odontogenic fibtoma, aneurysmal bone cyst and neurofibroma. 2) Radiopaque mass lesions-odontoma, cementoma and osteoma. 3) Mixed patterns-ossifying fibroma, cementifying fibroma, calcifying odontogenic epithelial tumor and hemangioma. It was concluded that the radiographic examination was of value to diagnose the benign tumors of the mandible in symptomless patients.

  18. [Models and computation methods of EEG forward problem].

    Science.gov (United States)

    Zhang, Yinghcun; Zou, Ling; Zhu, Shanan

    2004-04-01

    The research of EEG is of grat significance and clinical importance in studying the cognitive function and neural activity of the brain. There are two key problems in the field of EEG, EEG forward problem and EEG inverse problem. EEG forward problem which aims to get the distribution of the scalp potential due to the known current distribution in the brain is the basis of the EEG inverse problem. Generally, EEG inverse problem depends on the accuracy and efficiency of the computational method of EEG forward problem. This paper gives a review of the head model and corresponding computational method about EEG forward problem studied in recent years.

  19. Multi-class EEG classification of voluntary hand movement directions

    Science.gov (United States)

    Robinson, Neethu; Guan, Cuntai; Vinod, A. P.; Keng Ang, Kai; Tee, Keng Peng

    2013-10-01

    Objective. Studies have shown that low frequency components of brain recordings provide information on voluntary hand movement directions. However, non-invasive techniques face more challenges compared to invasive techniques. Approach. This study presents a novel signal processing technique to extract features from non-invasive electroencephalography (EEG) recordings for classifying voluntary hand movement directions. The proposed technique comprises the regularized wavelet-common spatial pattern algorithm to extract the features, mutual information-based feature selection, and multi-class classification using the Fisher linear discriminant. EEG data from seven healthy human subjects were collected while they performed voluntary right hand center-out movement in four orthogonal directions. In this study, the movement direction dependent signal-to-noise ratio is used as a parameter to denote the effectiveness of each temporal frequency bin in the classification of movement directions. Main results. Significant (p movement direction dependent modulation in the EEG data was identified largely towards the end of movement at low frequencies (≤6 Hz) from the midline parietal and contralateral motor areas. Experimental results on single trial classification of the EEG data collected yielded an average accuracy of (80.24 ± 9.41)% in discriminating the four different directions using the proposed technique on features extracted from low frequency components. Significance. The proposed feature extraction strategy provides very high multi-class classification accuracies, and the results are proven to be more statistically significant than existing methods. The results obtained suggest the possibility of multi-directional movement classification from single-trial EEG recordings using the proposed technique in low frequency components.

  20. EEG use in a tertiary referral centre.

    LENUS (Irish Health Repository)

    O'Toole, O

    2011-11-15

    The aim of this study was to retrospectively audit all electroencephalograms (EEGs) done over a 2-month period in 2009 by the Neurophysiology Department at Cork University Hospital. There were 316 EEGs performed in total, of which 176\\/316 (56%) were done within 24 hours of request. Out of 316 EEGs, 208 (66%) were considered \\'appropriate\\' by SIGN and NICE guidelines; 79\\/208 (38%) had abnormal EEGs and 28 of these abnormal EEGs had epileptiform features. There were 108\\/316 (34%) \\'inappropriate\\' requests for EEG; of these 15\\/108 (14%) were abnormal. Of the 67\\/316 (21%) patients who had EEGs requested based on a history of syncope\\/funny turns: none of these patients had epileptiform abnormalities on their EEGs. Our audit demonstrates that EEGs are inappropriately over-requested in our institution in particular for cases with reported \\'funny turns\\' and syncope. The yield from EEGs in this cohort of patients was low as would be expected.

  1. Benign Papules and Nodules of Oral Mucosa

    Directory of Open Access Journals (Sweden)

    Mehmet Salih Gürel

    2012-12-01

    Full Text Available This article reviews some of the more common benign oral papules and nodules of oral mucosa with emphasis on their etiology, epidemiology, clinical presentation, histopathology, and treatment. These lesions include mucocele, traumatic fibroma, epulis, pyogenic granuloma, oral papilloma, oral warts, lymphangioma, hemangioma, lipoma, oral nevi and some soft tissue benign tumors. These benign lesions must be separated clinically and histologically from precancerous and malign neoplastic lesions. Accurate clinico-pathological diagnosis is mandatory to insure appropriate therapy.

  2. Benign breast lesions detected by positron emission tomography-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Benveniste, Ana P., E-mail: apbenveniste@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Yang, Wei, E-mail: wyang@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Benveniste, Marcelo F., E-mail: mfbenveniste@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Mawlawi, Osama R., E-mail: omawlawi@mdanderson.org [Department of imaging physics, The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Marom, Edith M., E-mail: emarom@mdanderson.org [Department of Diagnostic Radiology,The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-15

    {sup 18}F-fluorodeoxyglucose positron emission computed tomography (FDG PET-CT) is widely used in the initial staging and response evaluation of patients with malignancy. This review describes a spectrum of benign breast findings incidentally detected by FDG PET-CT at staging that may be misinterpreted as malignancy. We describe the pattern of distribution and intensity of FDG uptake in a spectrum of benign breast diseases with their corresponding typical morphological imaging characteristics to help the nuclear medicine physician and/or general radiologist identify benign lesions, avoiding unnecessary breast imaging work-up and biopsies.

  3. Behavioural and EEG effects of chronic rapamycin treatment in a mouse model of tuberous sclerosis complex.

    Science.gov (United States)

    Cambiaghi, Marco; Cursi, Marco; Magri, Laura; Castoldi, Valerio; Comi, Giancarlo; Minicucci, Fabio; Galli, Rossella; Leocani, Letizia

    2013-04-01

    Tuberous Sclerosis Complex (TSC) is a multisystem genetic disorder caused by mutation in either Tsc1 or Tsc2 genes that leads to the hyper activation of the mTOR pathway, a key signalling pathway for synaptic plasticity. TSC is characterized by benign tumors arising in different organs and severe neuropsychiatric symptoms, such as epilepsy, intellectual disability, autism, anxiety and depressive behaviour. Rapamycin is a potent inhibitor of mTOR and its efficacy in treating epilepsy and neurological symptoms remains elusive. In a mouse model in which Tsc1 has been deleted in embryonic telencephalic neural stem cells, we analyzed anxiety- and depression-like behaviour by elevated-plus maze (EPM), open-field test (OFT), forced-swim test (FST) and tail-suspension test (TST), after chronic administration of rapamycin. In addition, spectral analysis of background EEG was performed. Rapamycin-treated mutant mice displayed a reduction in anxiety- and depression-like phenotype, as shown by the EPM/OFT and FST, respectively. These results were inline with EEG power spectra outcomes. The same effects of rapamycin were observed in wild-type mice. Notably, in heterozygous animals we did not observe any EEG and/or behavioural variation after rapamycin treatment. Together these results suggest that both TSC1 deletion and chronic rapamycin treatment might have a role in modulating behaviour and brain activity, and point out to the potential usefulness of background EEG analysis in tracking brain dysfunction in parallel with behavioural testing.

  4. Elements of EEG signal processing.

    Science.gov (United States)

    Rampil, I J

    1987-01-01

    It is difficult to find well controlled clinical studies comparing the utility of the numerous EEG measures which have been described. A brief summary of the literature reveals a number of promising case reports, a few large series of patients, and fewer well-designed, well-controlled studies. The very abundance of algorithms makes even technical comparisons of the ability of each to transduce and reflect clinical changes useful (27, 29). Most studies are positive; but thus far (as with so many procedures in medicine), there is no definitive study demonstrating an unequivocal benefit to patients who are monitored with automated, online EEG analysis. That such a study may never be done should not detract from the possible benefits these techniques may bring to clinical practice, most particularly preparing the way for effective brain monitoring in situations in which it was impractical before.

  5. The Detection of Hidden Periodicities in EEG

    Institute of Scientific and Technical Information of China (English)

    YOU Rong-yi

    2007-01-01

    Abstract.A novel method for detecting the hidden periodicities in EEG is proposed.By using a width-varying window in the time domain, the structure function of EEG time series is defined. It is found that the minima of the structure function, within a finite window width, can be found regularly, which indicate that there are some certain periodicities associated with EEG time series. Based on the structure function, a further quadratic structure function of EEG time series is defined. By quadratic structure function, it can be seen that the periodicities of EEG become more obvious, moreover, the period of EEG can be determined accurately. These results will be meaningful for studying the neuron activity inside the human brain.

  6. EEG correlates of virtual reality hypnosis.

    Science.gov (United States)

    White, David; Ciorciari, Joseph; Carbis, Colin; Liley, David

    2009-01-01

    The study investigated hypnosis-related electroencephalographic (EEG) coherence and power spectra changes in high and low hypnotizables (Stanford Hypnotic Clinical Scale) induced by a virtual reality hypnosis (VRH) induction system. In this study, the EEG from 17 participants (Mean age = 21.35, SD = 1.58) were compared based on their hypnotizability score. The EEG recording associated with a 2-minute, eyes-closed baseline state was compared to the EEG during a hypnosis-related state. This novel induction system was able to produce EEG findings consistent with previous hypnosis literature. Interactions of significance were found with EEG beta coherence. The high susceptibility group (n = 7) showed decreased coherence, while the low susceptibility group (n = 10) demonstrated an increase in coherence between medial frontal and lateral left prefrontal sites. Methodological and efficacy issues are discussed.

  7. Benign communicating hydrocephalus in children

    Energy Technology Data Exchange (ETDEWEB)

    Kendall, B.; Holland, I.

    1981-03-01

    A review was performed of the computed tomograms (CTs) of 500 children which had been reported as showing widening of the supratentorial subarachnoid spaces with normal cerebral substance. On the basis of this a radiological diagnosis of cerebral atrophy had been made in all but five, who were said to have mengalencephaly. From these, the children with large or abnormally enlarging heads, but normal or only slightly enlarged ventricles, were selected; there were 40 such cases (8%). The clinical condition either improved or remained stable over a period of 2 years; in the majority the scan abnormality regressed (22.5%) or remained static (67.5%). In three cases there was slight progression of the CT changes before stabilisation, but only one case developed classical communicating hydrocephalus necessitating a shunt procedure. This condition is a generally benign and mild form of communicating hydrocephalus, for which an aetiological factor was apparent in about two-thirds of the cases studied.

  8. Benign paroxysmal torticollis in infancy

    Directory of Open Access Journals (Sweden)

    Dimitrijević Lidija

    2006-01-01

    Full Text Available Background. Benign paroxysmal torticollis (BPT is an episodic functional disorder of unknown etiology, characterized by the periods of torticollic posturing of the head, that occurs in the early months of life in healthy children. Case report. We reported two patients with BPT. In the first patient the symptoms were observed at the age of day 20, and disappeared at the age of 3 years. There were 10 episodes, of which 2 were followed by vomiting, pallor, irritability and the abnormal trunk posture. In the second patient, a 12-month-old girl, BPT started from day 15. She had 4 episodes followed by vomiting in the first year. Both girls had the normal psychomotor development. All diagnostical tests were normal. Conclusion. The recognition of BPT, as well as its clinical course may help to avoid not only unnecessary tests and the treatment, but also the anxiety of the parents.

  9. Benign fibroxanthoma of the mandible

    Directory of Open Access Journals (Sweden)

    L Zouloumis

    2011-01-01

    Full Text Available Histiocytomas constitute a large group of tumors, the classification of which created a lot of confusion in the past. For this reason, various attempts were carried out during the last years so that a widely accepted classification system could be defined. Fibroxanthomas, according to contemporary data, are classified into benign histiocytomas and they are mostly located at the skin of extremities. They are rarely localized in the area of the head and neck, where they are found commonly in soft tissue. Fibroxanthomas located at the bones of oral and maxillofacial region are extremely rare. The purpose of this paper is to present a case of a fibroxanthoma located at the mandible as well as to analyze the histological findings of the lesion on which the diagnosis and differential diagnosis were based.

  10. Independent EEG sources are dipolar.

    Directory of Open Access Journals (Sweden)

    Arnaud Delorme

    Full Text Available Independent component analysis (ICA and blind source separation (BSS methods are increasingly used to separate individual brain and non-brain source signals mixed by volume conduction in electroencephalographic (EEG and other electrophysiological recordings. We compared results of decomposing thirteen 71-channel human scalp EEG datasets by 22 ICA and BSS algorithms, assessing the pairwise mutual information (PMI in scalp channel pairs, the remaining PMI in component pairs, the overall mutual information reduction (MIR effected by each decomposition, and decomposition 'dipolarity' defined as the number of component scalp maps matching the projection of a single equivalent dipole with less than a given residual variance. The least well-performing algorithm was principal component analysis (PCA; best performing were AMICA and other likelihood/mutual information based ICA methods. Though these and other commonly-used decomposition methods returned many similar components, across 18 ICA/BSS algorithms mean dipolarity varied linearly with both MIR and with PMI remaining between the resulting component time courses, a result compatible with an interpretation of many maximally independent EEG components as being volume-conducted projections of partially-synchronous local cortical field activity within single compact cortical domains. To encourage further method comparisons, the data and software used to prepare the results have been made available (http://sccn.ucsd.edu/wiki/BSSComparison.

  11. Juvenile myoclonic epilepsy: clinical and EEG features

    DEFF Research Database (Denmark)

    Pedersen, S B; Petersen, K A

    1998-01-01

    We aimed to characterize the clinical profile and EEG features of 43 patients with juvenile myoclonic epilepsy. In a retrospective design we studied the records of, and re-interviewed, 43 patients diagnosed with JME from the epilepsy clinic data base. Furthermore, available EEGs were re-evaluated...... were sleep deprivation (84%), stress (70%), and alcohol consumption (51%). EEG findings included rapid spike-wave and polyspike-wave....

  12. EEG Derived Neuronal Dynamics during Meditation: Progress and Challenges

    Directory of Open Access Journals (Sweden)

    Chamandeep Kaur

    2015-01-01

    Full Text Available Meditation advances positivity but how these behavioral and psychological changes are brought can be explained by understanding neurophysiological effects of meditation. In this paper, a broad spectrum of neural mechanics under a variety of meditation styles has been reviewed. The overall aim of this study is to review existing scientific studies and future challenges on meditation effects based on changing EEG brainwave patterns. Albeit the existing researches evidenced the hold for efficacy of meditation in relieving anxiety and depression and producing psychological well-being, more rigorous studies are required with better design, considering client variables like personality characteristics to avoid negative effects, randomized controlled trials, and large sample sizes. A bigger number of clinical trials that concentrate on the use of meditation are required. Also, the controversial subject of epileptiform EEG changes and other adverse effects during meditation has been raised.

  13. [EEG spatial organization and activation of creative processes].

    Science.gov (United States)

    Sviderskaia, N E; Dashchinskaia, T N; Taratynova, G V

    2001-01-01

    Characteristic features of the spatino-temporal EEG organization of 24 right-handed children (aged from 8 to 13 years) were studied after stimulation of creative activity by the method of self-regulation of the brain functional state (Russian Inventor's Certificate no. 2157707, 01.06.1999). The multiparametric analysis of baseline recordings derived from 24 cortical points made it possible to find the most probable pattern of changes in the spatial synchronization of biopotentials, including increase in activity in the right anterior and left posterior cortical regions. These changes were accompanied by a rise in the information-energy parameter (the ratio between coherence and spectral power of potentials). This phenomenon may testify to a transition to the "economic" condition of information processing. Differences in EEG frequency characteristics corresponding to different levels of imagination and creative intuition were revealed.

  14. Automatic seizure detection: going from sEEG to iEEG

    DEFF Research Database (Denmark)

    Henriksen, Jonas; Remvig, Line Sofie; Madsen, Rasmus Elsborg

    2010-01-01

    of ictal and non-ictal iEEG were obtained. Characteristics of the seizures are represented by use of wavelet transformation (WT) features and classified by a support vector machine. When implementing a method used for sEEG on iEEG data, a great improvement in performance was obtained when the high...

  15. The amendment of the Renewable Energy Law (EEG); Die Novelle des Erneuerbare-Energien-Gesetzes (EEG)

    Energy Technology Data Exchange (ETDEWEB)

    Menze, Julian [Erdgas Muenster GmbH, Muenster (Germany)

    2011-07-01

    The Act for the reformation of the legal framework for the support of the power generation from renewable energy sources mainly consists of an amendment to the Renewable Energy Law (EEG) and becomes effective on 1st January, 2012. The author of the contribution under consideration reports on the most important new features of the EEG and gives an overview of the EEG 2012.

  16. Tomographic imaging of the spleen: the role of morphological and metabolic features in differentiating benign from malignant diseases.

    Science.gov (United States)

    Mainenti, Pier Paolo; Iodice, Delfina; Cozzolino, Immacolata; Segreto, Sabrina; Capece, Sergio; Sica, Giacomo; Magliulo, Mario; Ciancia, Giuseppe; Pace, Leonardo; Salvatore, Marco

    2012-01-01

    To evaluate the tomographic features in differentiating benign from malignant splenic diseases, 54 patients with a cytohistological examination and a contrast-enhanced multidetector computed tomography (ce-MDCT) and/or positron emission tomography/computed tomography (PET/CT) were retrospectively selected. Significant associations were observed between ce-MDCT Pattern 3 (focal hyperdense lesion) and Pattern 4 (infarcts/cysts) as well as PET/CT Pattern 3 (focal photopenia/diffuse uptakebenign pathologies, and between ce-MDCT Pattern 1 (splenomegaly without focal lesions) and Pattern 2 (focal hypodense lesion) as well as PET/CT Pattern 1 (diffuse uptake ≥ liver) and Pattern 2 (focal increased uptake) and malignant diseases. No significant association between benign or malignant diseases and spleen volumes and maximum standardized uptake value (SUV(max)) as well as lesion characteristics was observed. The metabolic data do not improve the performance of morphological patterns.

  17. Wavelet Variance Analysis of EEG Based on Window Function

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yuan-zhuang; YOU Rong-yi

    2014-01-01

    A new wavelet variance analysis method based on window function is proposed to investigate the dynamical features of electroencephalogram (EEG).The ex-prienmental results show that the wavelet energy of epileptic EEGs are more discrete than normal EEGs, and the variation of wavelet variance is different between epileptic and normal EEGs with the increase of time-window width. Furthermore, it is found that the wavelet subband entropy (WSE) of the epileptic EEGs are lower than the normal EEGs.

  18. How about a Bayesian M/EEG imaging method correcting for incomplete spatio-temporal priors

    DEFF Research Database (Denmark)

    Stahlhut, Carsten; Attias, Hagai T.; Sekihara, Kensuke;

    2013-01-01

    In this contribution we present a hierarchical Bayesian model, sAquavit, to tackle the highly ill-posed problem that follows with MEG and EEG source imaging. Our model facilitates spatio-temporal patterns through the use of both spatial and temporal basis functions. While in contrast to most...... previous spatio-temporal inverse M/EEG models, the proposed model benefits of consisting of two source terms, namely, a spatio-temporal pattern term limiting the source configuration to a spatio-temporal subspace and a source correcting term to pick up source activity not covered by the spatio...

  19. Benign paroxysmal positional vertigo in Parkinson's disease

    NARCIS (Netherlands)

    Wensen, E. van; Leeuwen, R.B. van; Zaag-Loonen, H.J. van der; Masius-Olthof, S.; Bloem, B.R.

    2013-01-01

    BACKGROUND: Dizziness is a frequent complaint of patients with Parkinson's disease (PD), and orthostatic hypotension (OH) is often thought to be the cause. We studied whether benign paroxysmal positional vertigo (BPPV) could also be an explanation. AIM: To assess the prevalence of benign paroxysmal

  20. Clinical and electroencephalographic characteristics of benign occipital epilepsy of childhood in two tertiary Brazilian hospitals

    Directory of Open Access Journals (Sweden)

    Soniza Vieira Alves-Leon

    2011-08-01

    Full Text Available This study intended to investigate the clinical and electroencephalographic benign occipital epilepsy of childhood (BOEC characteristics in a population sample of patients from two tertiary Brazilian hospitals. We analyzed retrospectively 4912 electroencephalograms (EEGs records, and the included patients were submitted to a new clinical and EEG evaluation. Were included 12 (0.92% patients; 4 (33.3% with criteria for early BOEC; 6 (50% for late form and 2 (16.7% with superimposed early and late onset forms. After new investigation, 2 (16.7% had normal EEG; 4 (33.3% had paroxysms over the occipital region; 3 (25% over the temporal posterior regions and 3 (25% over the posterior regions. Sharp waves were the predominant change, occurring in 8 (66.6%; spike and slow wave complexes in 1 (8.3% and sharp and slow wave complexes in 1 (8.3%. Vomiting, headache and visual hallucinations were the most common ictal manifestations, presented in 100% of patients with superimposed forms. Vomiting were absent in the late form and headache was present in all forms of BOEC.

  1. Multisensory integration of dynamic emotional faces and voices: method for simultaneous EEG-fMRI measurements.

    Science.gov (United States)

    Schelenz, Patrick D; Klasen, Martin; Reese, Barbara; Regenbogen, Christina; Wolf, Dhana; Kato, Yutaka; Mathiak, Klaus

    2013-01-01

    Combined EEG-fMRI analysis correlates time courses from single electrodes or independent EEG components with the hemodynamic response. Implementing information from only one electrode, however, may miss relevant information from complex electrophysiological networks. Component based analysis, in turn, depends on a priori knowledge of the signal topography. Complex designs such as studies on multisensory integration of emotions investigate subtle differences in distributed networks based on only a few trials per condition. Thus, they require a sensitive and comprehensive approach which does not rely on a-priori knowledge about the underlying neural processes. In this pilot study, feasibility and sensitivity of source localization-driven analysis for EEG-fMRI was tested using a multisensory integration paradigm. Dynamic audiovisual stimuli consisting of emotional talking faces and pseudowords with emotional prosody were rated in a delayed response task. The trials comprised affectively congruent and incongruent displays. In addition to event-locked EEG and fMRI analyses, induced oscillatory EEG responses at estimated cortical sources and in specific temporo-spectral windows were correlated with the corresponding BOLD responses. EEG analysis showed high data quality with less than 10% trial rejection. In an early time window, alpha oscillations were suppressed in bilateral occipital cortices and fMRI analysis confirmed high data quality with reliable activation in auditory, visual and frontal areas to the presentation of multisensory stimuli. In line with previous studies, we obtained reliable correlation patterns for event locked occipital alpha suppression and BOLD signal time course. Our results suggest a valid methodological approach to investigate complex stimuli using the present source localization driven method for EEG-fMRI. This novel procedure may help to investigate combined EEG-fMRI data from novel complex paradigms with high spatial and temporal

  2. [The study of sleep in full term and preterm neonates with EEG polygraphy].

    Science.gov (United States)

    Borsini, W; Lambruschini, P; Marcacci, G

    1990-01-01

    We accomplished polygraphies in two groups of infants: 1) preterm infants born before 33 weeks CA, and recorded between 33 and 48 weeks CA; 2) full term infants, recorded between 39 and 48 weeks CA. We compared in each group of infants: 1) the development of behavioral states organization; 2) the maturation of cortical bioelectric activities; 3) the development of concordance between behavioral states and EEG pattern; 4) sequences of behavioral states and EEG pattern when the babies fall asleep. In all the aspects considered, we describe some developmental changes, to understand how, through these changes, the newborn sleep-wake ultradian cycle is replaced by 24 hr-cycle, typical of the infantile period. This basic process is expression of maturation of the central nervous system because it is related to CA and not to extrauterine experience. The EEG-polygraph usually used in clinical practice allow us to follow these extraordinary transformations very closely.

  3. Extraction of features from sleep EEG for Bayesian assessment of brain development

    Science.gov (United States)

    2017-01-01

    Brain development can be evaluated by experts analysing age-related patterns in sleep electroencephalograms (EEG). Natural variations in the patterns, noise, and artefacts affect the evaluation accuracy as well as experts’ agreement. The knowledge of predictive posterior distribution allows experts to estimate confidence intervals within which decisions are distributed. Bayesian approach to probabilistic inference has provided accurate estimates of intervals of interest. In this paper we propose a new feature extraction technique for Bayesian assessment and estimation of predictive distribution in a case of newborn brain development assessment. The new EEG features are verified within the Bayesian framework on a large EEG data set including 1,100 recordings made from newborns in 10 age groups. The proposed features are highly correlated with brain maturation and their use increases the assessment accuracy. PMID:28323852

  4. Open Ephys electroencephalography (Open Ephys +EEG): a modular, low-cost, open-source solution to human neural recording.

    Science.gov (United States)

    Black, Christopher; Voigts, Jakob; Agrawal, Uday; Ladow, Max; Santoyo, Juan; Moore, Christopher; Jones, Stephanie

    2017-03-07

    Electroencephalography (EEG) offers a unique opportunity to study human neural activity non-invasively with millisecond resolution using minimal equipment in or outside of a lab setting. EEG can be combined with a number of techniques for closed-loop experiments, where external devices are driven by specific neural signals. For example, EEG signals have been used to regulate anesthetic delivery, to control brain-computer interfaces, and to drive transcranial alternating current stimulation for the treatment of psychiatric illness. However, reliable, commercially available EEG systems are expensive, often making them impractical for individual use and research development. Moreover, by design, a majority of these systems cannot be easily altered to the specification needed by the end user. This rigidity makes it extremely difficult or infeasible to adapt EEG to novel closed-loop experiments. For instance, many current systems are not able to communicate with software and hardware from other vendors, nor are they able to achieve low-latency timescales (100 ms) necessary to operate on the fast patterns of neural activities. Recently, open-source alternatives to commercial systems have been developed that can eliminate these problems, driving down research costs and promoting collaborations and innovations. Here, we present methods to expand the use of a commercially available, open-source electrophysiology system, Open Ephys (www.openephys.org), to include human EEG recordings providing a novel technique for low-cost, easily-adaptable EEG recording. We describe the equipment and protocol necessary to interface various EEG caps with the Open Ephys acquisition board, and detail methods for processing data. We present applications of Open Ephys + EEG as a research tool and discuss how this innovative EEG technology lays a framework for improved closed-loop paradigms and novel brain-computer interface experiments.

  5. Cognitive and other neuropsychological profiles in children with newly diagnosed benign rolandic epilepsy

    Directory of Open Access Journals (Sweden)

    Soonhak Kwon

    2012-10-01

    Full Text Available &lt;B&gt;Purpose:&lt;/B&gt; Although benign rolandic epilepsy (BRE is a benign condition, it may be associated with a spectrum of behavioral, psychiatric, and cognitive disorders. This study aimed to assess the cognitive and other neuropsychological profiles of children with BRE. &lt;B&gt;Methods:&lt;/B&gt; In total, 23 children with BRE were consecutively recruited. All children underwent sleep electroencephalography (EEG and were assessed on a battery of comprehensive neuropsychological tests including the Korean versions of the Wechsler intelligence scale for children III, frontal executive neuropsychological test, rey complex figure test, Wisconsin card sorting test, attention deficit diagnostic scale, and child behavior checklist scale. &lt;B&gt;Results:&lt;/B&gt; The study subjects included 13 boys and 10 girls aged 9.0±1.6 years. Our subjects showed an average monthly seizure frequency of 0.9±0.7, and a majority of them had focal seizures (70%. The spike index (frequency/min was 4.1±5.3 (right and 13.1±15.9 (left. Of the 23 subjects, 9 showed frequent spikes (&gt;10/min on the EEG. The subjects had normal cognitive and frontal executive functions, memory, and other neuropsychological sub-domain scores, even though 8 children (35% showed some evidence of learning difficulties, attention deficits, and aggressive behavior. &lt;B&gt;Conclusion:&lt;/B&gt; Our data have limited predictive value; however, these data demonstrate that although BRE appears to be benign at the onset, children with BRE might develop cognitive, behavioral, and other psychiatric disorders during the active phase of epilepsy, and these problems may even outlast the BRE. Therefore, we recommend scrupulous follow-up for children with BRE.

  6. Objective Audiometry using Ear-EEG

    DEFF Research Database (Denmark)

    Christensen, Christian Bech; Kidmose, Preben

    life. Ear-EEG may therefore be an enabling technology for objective audiometry out of the clinic, allowing regularly fitting of the hearing aids to be made by the users in their everyday life environment. In this study we investigate the application of ear-EEG in objective audiometry....

  7. Resting EEG asymmetry and spider phobia

    NARCIS (Netherlands)

    Merckelbach, H; Muris, P; Pool, K; de Jong, Peter

    1998-01-01

    This study examined whether resting EEG asymmetries are related to symptom severity and treatment outcome in spider phobia. Prior to treatment, EEG was recorded in a sample of spider phobic patients (N = 16). Correlations between frontal and parietal asymmetries in alpha power, on the one hand, and

  8. Continuous EEG Monitoring in Aneurysmal Subarachnoid Hemorrhage

    DEFF Research Database (Denmark)

    Kondziella, Daniel; Friberg, Christian Kærsmose; Wellwood, Ian

    2015-01-01

    BACKGROUND: Continuous EEG (cEEG) may allow monitoring of patients with aneurysmal subarachnoid hemorrhage (SAH) for delayed cerebral ischemia (DCI) and seizures, including non-convulsive seizures (NCSz), and non-convulsive status epilepticus (NCSE). We aimed to evaluate: (a) the diagnostic...

  9. Nocturia and benign prostatic hyperplasia

    Directory of Open Access Journals (Sweden)

    Laketić Darko

    2008-01-01

    Full Text Available Background/Aim. Nocturia often occurs in patients with benign prostate hyperplasia (BPH. The aim of the study was to investigate the frequency of nocturia in patients with BPH. Nocturia and other factors associated with it were also investigated. Methods. Forty patients with the confirmed diagnosis of BPH were studied. Transurethral and transvesical prostatectomy were performed in all the patients. Symptoms were evaluated with the International Prostate Symptom Score before, as well as three and six months after the surgery. All the results were compared with the control group. Results. There was no statistically significant difference between the patients before and after the surgery regarding nocturia. There was, however, a statistically significant difference between the operated patients and the control group regarding nocturia, as well as a statistically significant correlation between noctruia and the age of the patients in both the investigated and the control group. A correlation also existed between nocturia and the prostatic size. Conclusion. There was no statistically significant improvement in symptoms of nocturia after the surgery. It is necessary to be very careful in decision making in patients with nonabsolute indiction for surgery and isolated bothersome symptom of nocturia. Age of a patient should also be considered in the evaluation of favorable result of the surgery because of a significant correlation between noctura and the age of a patient.

  10. Long-Term Clinical and Electroencephalography (EEG) Consequences of Idiopathic Partial Epilepsies.

    Science.gov (United States)

    Dörtcan, Nimet; Tekin Guveli, Betul; Dervent, Aysin

    2016-05-03

    BACKGROUND Idiopathic partial epilepsies of childhood (IPE) affect a considerable proportion of children. Three main electroclinical syndromes of IPE are the Benign Childhood Epilepsy with Centro-temporal Spikes (BECTS), Panayiotopoulos Syndrome (PS), and Childhood Epilepsy with Occipital Paroxysms (CEOP). In this study we investigated the long-term prognosis of patients with IPE and discussed the semiological and electroencephalography (EEG) data in terms of syndromic characteristics. MATERIAL AND METHODS This study included a group of consecutive patients with IPE who had been followed since 1990. Demographic and clinical variables were investigated. Patients were divided into 3 groups - A: Cases suitable for a single IPE (BECTS, PS and CEOP); B: cases with intermediate characteristics within IPEs; and C: cases with both IPE and IGE characteristics. Long-term data regarding the individual seizure types and EEG findings were re-evaluated. RESULTS A total of 61 patients were included in the study. Mean follow-up duration was 7.8 ± 4.50 years. The mean age at onset of seizures was 7.7 years. There were 40 patients in group A 40, 14 in group B, and 7 in group C. Seizure and EEG characteristics were also explored independently from the syndromic approach. Incidence of autonomic seizures is considerably high at 2-5 years and incidence of oromotor seizures is high at age 9-11 years. The EEG is most abnormal at 6-8 years. The vast majority (86%) of epileptic activity (EA) with parietooccipital is present at 2-5 years, whereas EA with fronto-temporal or multiple sites become more abundant between ages 6 and 11. CONCLUSIONS Results of the present study provide support for the age-related characteristics of the seizures and EEGs in IPE syndromes. Acknowledgement of those phenomena may improve the management of IPEs and give a better estimate of the future consequences.

  11. Wearable EEG via lossless compression.

    Science.gov (United States)

    Dufort, Guillermo; Favaro, Federico; Lecumberry, Federico; Martin, Alvaro; Oliver, Juan P; Oreggioni, Julian; Ramirez, Ignacio; Seroussi, Gadiel; Steinfeld, Leonardo

    2016-08-01

    This work presents a wearable multi-channel EEG recording system featuring a lossless compression algorithm. The algorithm, based in a previously reported algorithm by the authors, exploits the existing temporal correlation between samples at different sampling times, and the spatial correlation between different electrodes across the scalp. The low-power platform is able to compress, by a factor between 2.3 and 3.6, up to 300sps from 64 channels with a power consumption of 176μW/ch. The performance of the algorithm compares favorably with the best compression rates reported up to date in the literature.

  12. [EEG correlates of social creativity].

    Science.gov (United States)

    Razumnikova, O M; Finikov, S B

    2010-01-01

    EEG correlates of social creativity defined as ability to originally and flexibly interpret social significant situations were studied. It was found that the alpha2 and gamma2 rhythms are specific bands which make it possible to tell the difference between social creativity and control task. Solving socially significant problems in experimental conditions is accompanied by an increase in the power of the delta and gamma2 bands and desynchronization in the alpha2 band less pronounced in divergent tasks than during the interpretation of convergent visual stimuli.

  13. Detecting behavioral microsleeps using EEG and LSTM recurrent neural networks.

    Science.gov (United States)

    Davidson, P R; Jones, R D; Peiris, M T

    2005-01-01

    Lapses in visuomotor performance are often associated with behavioral microsleep events. Experiencing a lapse of this type while performing an important task can have catastrophic consequences. A warning system capable of reliably detecting patterns in EEG occurring before or during a lapse has the potential to save many lives. We are developing a behavioral microsleep detection system which employs Long Short'Term Memory (LSTM) recurrent neural networks. To train and validate the system, EEG, facial video and tracking data were collected from 15 subjects performing a visuomotor tracking task for 2 1-hour sessions. This provided behavioral information on lapse events with good temporal resolution. We developed an automated behavior rating system and trained it to estimate the mean opinion of 3 human raters on the likelihood of a lapse. We then trained an LSTM neural network to estimate the output of the lapse rating system given only EEG spectral data. The detection system was designed to operate in real-time without calibration for individual subjects. Preliminary results show the system is not reliable enough for general use, but results from some tracking sessions encourage further investigation of the reported approach.

  14. Early postnatal EEG features of perinatal arterial ischaemic stroke with seizures.

    Directory of Open Access Journals (Sweden)

    Evonne Low

    Full Text Available Stroke is the second most common cause of seizures in term neonates and is associated with abnormal long-term neurodevelopmental outcome in some cases.To aid diagnosis earlier in the postnatal period, our aim was to describe the characteristic EEG patterns in term neonates with perinatal arterial ischaemic stroke (PAIS seizures.Retrospective observational study.Neonates >37 weeks born between 2003 and 2011 in two hospitals.Continuous multichannel video-EEG was used to analyze the background patterns and characteristics of seizures. Each EEG was assessed for continuity, symmetry, characteristic features and sleep cycling; morphology of electrographic seizures was also examined. Each seizure was categorized as electrographic-only or electroclinical; the percentage of seizure events for each seizure type was also summarized.Nine neonates with PAIS seizures and EEG monitoring were identified. While EEG continuity was present in all cases, the background pattern showed suppression over the infarcted side; this was quite marked (>50% amplitude reduction when the lesion was large. Characteristic unilateral bursts of theta activity with sharp or spike waves intermixed were seen in all cases. Sleep cycling was generally present but was more disturbed over the infarcted side. Seizures demonstrated a characteristic pattern; focal sharp waves/spike-polyspikes were seen at frequency of 1-2 Hz and phase reversal over the central region was common. Electrographic-only seizure events were more frequent compared to electroclinical seizure events (78 vs 22%.Focal electrographic and electroclinical seizures with ipsilateral suppression of the background activity and focal sharp waves are strong indicators of PAIS. Approximately 80% of seizure events were the result of clinically unsuspected seizures in neonates with PAIS. Prolonged and continuous multichannel video-EEG monitoring is advocated for adequate seizure surveillance.

  15. BENIGN INTRACRANIAL HYPOTENSION WITH INCIDENTAL PARASAGITTAL MENINGIOMA

    Directory of Open Access Journals (Sweden)

    Sukumar

    2015-12-01

    Full Text Available Benign intracranial hypotension, otherwise called as idiopathic intracranial hypotension is caused by CSF leaks due to disruption in spinal meninges. It is most commonly caused by disruption and leak at cervical and thoracic spine. Imaging is sometimes the most important key to the diagnosis of idiopathic intracranial hypotension, which helps in appropriate treatment of the patient. Here, we are presenting a case of benign intracranial hypotension associated with incidental parasagittal meningioma. The presence of benign intracranial hypotension was confirmed by taking MR myelogram.

  16. Behavioral and EEG evidence for auditory memory suppression

    Directory of Open Access Journals (Sweden)

    Maya Elizabeth Cano

    2016-03-01

    Full Text Available The neural basis of motivated forgetting using the Think/No-Think (TNT paradigm is receiving increased attention with a particular focus on the mechanisms that enable memory suppression. However, most TNT studies have been limited to the visual domain. To assess whether and to what extent direct memory suppression extends across sensory modalities, we examined behavioral and electroencephalographic (EEG effects of auditory Think/No-Think in healthy young adults by adapting the TNT paradigm to the auditory modality. Behaviorally, suppression of memory strength was indexed by prolonged response times during the retrieval of subsequently remembered No-Think words. We examined task-related EEG activity of both attempted memory retrieval and inhibition of a previously learned target word during the presentation of its paired associate. Event-related EEG responses revealed two main findings: 1 a centralized Think > No-Think positivity during auditory word presentation (from approximately 0-500ms, and 2 a sustained Think positivity over parietal electrodes beginning at approximately 600ms reflecting the memory retrieval effect which was significantly reduced for No-Think words. In addition, word-locked theta (4-8 Hz power was initially greater for No-Think compared to Think during auditory word presentation over fronto-central electrodes. This was followed by a posterior theta increase indexing successful memory retrieval in the Think condition.The observed event-related potential pattern and theta power analysis are similar to that reported in visual Think/No-Think studies and support a modality non-specific mechanism for memory inhibition. The EEG data also provide evidence supporting differing roles and time courses of frontal and parietal regions in the flexible control of auditory memory.

  17. Neurobiological correlates of EMDR monitoring - an EEG study.

    Directory of Open Access Journals (Sweden)

    Marco Pagani

    Full Text Available BACKGROUND: Eye Movement Desensitization and Reprocessing (EMDR is a recognized first-line treatment for psychological trauma. However its neurobiological bases have yet to be fully disclosed. METHODS: Electroencephalography (EEG was used to fully monitor neuronal activation throughout EMDR sessions including the autobiographical script. Ten patients with major psychological trauma were investigated during their first EMDR session (T0 and during the last one performed after processing the index trauma (T1. Neuropsychological tests were administered at the same time. Comparisons were performed between EEGs of patients at T0 and T1 and between EEGs of patients and 10 controls who underwent the same EMDR procedure at T0. Connectivity analyses were carried out by lagged phase synchronization. RESULTS: During bilateral ocular stimulation (BS of EMDR sessions EEG showed a significantly higher activity on the orbito-frontal, prefrontal and anterior cingulate cortex in patients at T0 shifting towards left temporo-occipital regions at T1. A similar trend was found for autobiographical script with a higher firing in fronto-temporal limbic regions at T0 moving to right temporo-occipital cortex at T1. The comparisons between patients and controls confirmed the maximal activation in the limbic cortex of patients occurring before trauma processing. Connectivity analysis showed decreased pair-wise interactions between prefrontal and cingulate cortex during BS in patients as compared to controls and between fusiform gyrus and visual cortex during script listening in patients at T1 as compared to T0. These changes correlated significantly with those occurring in neuropsychological tests. CONCLUSIONS: The ground-breaking methodology enabled our study to image for the first time the specific activations associated with the therapeutic actions typical of EMDR protocol. The findings suggest that traumatic events are processed at cognitive level following successful

  18. EEG activity during the performance of complex mental problems.

    Science.gov (United States)

    Jausovec, N; Jausovec, K

    2000-04-01

    This study investigated differences in cognitive processes related to problem complexity. It was assumed that these differences would be reflected in respondents' EEG activity--spectral power and coherence. A second issue of the study was to compare differences between the lower (alpha(1) = 7.9-10.0 Hz), and upper alpha band (alpha(2) = 10.1-12.9 Hz). In the first experiment two well-defined problems with two levels of complexity were used. Only minor differences in EEG power and coherence measures related to problem complexity were observed. In the second experiment divergent production problems resembling tasks on creativity tests were compared with dialectic problems calling for creative solutions. Differences in EEG power measures were mainly related to the form of problem presentation (figural/verbal). In contrast, coherence was related to the level of creativity needed to solve a problem. Noticeable increased intra- and interhemispheric cooperation between mainly the far distant brain regions was observed in the EEG activity of respondents while solving the dialectic problems. These results are explained by the more intense involvement of the long cortico-cortical fiber system in creative thinking. Differences between the lower and upper alpha band were significant for the power and coherence measures. In Experiment 2, fewer differences were observed in power measures in the upper alpha band than in the lower alpha band. A reverse pattern was observed for the coherence measures. These results hint to a functional independence of the two alpha bands, however, they do not allow to draw firm conclusions about their functional meanings. The study showed that it is unlikely that individuals solve well- and ill-defined problems by employing similar cognitive strategies.

  19. Two epileptic syndromes, one brain: childhood absence epilepsy and benign childhood epilepsy with centrotemporal spikes.

    Science.gov (United States)

    Cerminara, Caterina; Coniglio, Antonella; El-Malhany, Nadia; Casarelli, Livia; Curatolo, Paolo

    2012-01-01

    Childhood absence epilepsy (CAE) and benign childhood epilepsy with centrotemporal spikes (BCECTS), or benign rolandic epilepsy (BRE), are the most common forms of childhood epilepsy. CAE and BCECTS are well-known and clearly defined syndromes; although they are strongly dissimilar in terms of their pathophysiology, these functional epileptic disturbances share many features such as similar age at onset, overall good prognosis, and inheritance factors. Few reports are available on the concomitance of CAE and BCECTS in the same patients or the later occurrence of generalized epilepsy in patients with a history of partial epilepsy. In most cases described in the literature, absence seizures always started after the onset of benign focal epilepsy but the contrary has never occurred yet. We describe two patients affected by idiopathic generalized epileptic syndrome with typical absences, who experienced BCECTS after remission of seizures and normalization of EEG recordings. While the coexistence of different seizure types within an epileptic syndrome is not uncommon, the occurrence of childhood absence and BCECTS in the same child appears to be extremely rare, and this extraordinary event supports the hypothesis that CAE and BCECTS are two distinct epileptic conditions. However, recent interesting observations in animal models suggest that BCECTS and CAE could be pathophysiologically related and that genetic links could play a large role.

  20. Oxidative stress in benign prostate hyperplasia.

    Science.gov (United States)

    Zabaiou, N; Mabed, D; Lobaccaro, J M; Lahouel, M

    2016-02-01

    To assess the status of oxidative stress in benign prostate hyperplasia, a very common disease in older men which constitutes a public health problem in Jijel, prostate tissues were obtained by transvesical adenomectomy from 10 men with benign prostate hyperplasia. We measured the cytosolic levels of malondialdehyde (MDA) and glutathione (GSH) and cytosolic enzyme activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferase. The development of benign prostate hyperplasia is accompanied by impaired oxidative status by increasing levels of MDA, depletion of GSH concentrations and a decrease in the activity of all the antioxidant enzymes studied. These results have allowed us to understand a part of the aetiology of benign prostate hyperplasia related to oxidative stress.

  1. Migraine with benign episodic unilateral mydriasis

    Directory of Open Access Journals (Sweden)

    Jabr FI

    2011-06-01

    Full Text Available Nedaa Skeik1, Fadi I Jabr21Mayo Clinic, Rochester, MN, USA; 2Horizon Medical Center, Hospital Medicine, Dickson, TN, USAAbstract: Pupil asymmetry or anisocoria can have benign or malignant causes, and be categorized as acute or chronic. It can also be a normal finding in about 20% of cases. Benign episodic unilateral mydriasis is an isolated benign cause of intermittent pupil asymmetry. The exact pathophysiology is not always understood. According to one hypothesis, it is due to discordance between the sympathetic and parasympathetic systems. It is occasionally seen in patients with migraine. Some authors consider it a limited form of ophthalmoplegic migraine. We report a case of benign episodic unilateral mydriasis diagnosed in a 30-year-old lady with a history of migraine who had extensive negative neurological evaluation.Keywords: anisocoria, migraine, unilateral episodic mydriasis

  2. Genetics Home Reference: benign familial neonatal seizures

    Science.gov (United States)

    ... Facebook Share on Twitter Your Guide to Understanding Genetic Conditions Search MENU Toggle navigation Home Page Search ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions BFNS benign familial neonatal seizures ...

  3. Benign Metastatic Leiomyoma Presenting as a Hemothorax

    Directory of Open Access Journals (Sweden)

    Anna M. Ponea

    2013-01-01

    Full Text Available Uterine leiomyomas have been reported to metastasize to various organs including the lungs, skeletal muscles, bone marrow, peritoneum, and heart. They may present with symptoms related to the metastases several years after hysterectomy. These tumors regress after menopause, and it is rare to detect active tumors in postmenopausal women. Despite their ability to metastasize, they are considered to be benign due to the lack of anaplasia. Pulmonary benign metastasizing leiomyoma is usually detected in the form of pulmonary nodules incidentally on imaging. Tissue biopsy of these nodules is required to identify them as benign metastasizing leiomyomas. Immunohistochemical analysis and molecular profiling may further help detect any malignant transformation in it. Untreated pulmonary benign metastasizing leiomyoma may result in the formation of cystic structures, destruction of lung parenchyma, and hemothorax and may cause respiratory failure. Surgical resection and hormonal therapy help prevent progression of this disease and provide an avenue for a cure.

  4. Benign metastatic leiomyoma presenting as a hemothorax.

    Science.gov (United States)

    Ponea, Anna M; Marak, Creticus P; Goraya, Harmeen; Guddati, Achuta K

    2013-01-01

    Uterine leiomyomas have been reported to metastasize to various organs including the lungs, skeletal muscles, bone marrow, peritoneum, and heart. They may present with symptoms related to the metastases several years after hysterectomy. These tumors regress after menopause, and it is rare to detect active tumors in postmenopausal women. Despite their ability to metastasize, they are considered to be benign due to the lack of anaplasia. Pulmonary benign metastasizing leiomyoma is usually detected in the form of pulmonary nodules incidentally on imaging. Tissue biopsy of these nodules is required to identify them as benign metastasizing leiomyomas. Immunohistochemical analysis and molecular profiling may further help detect any malignant transformation in it. Untreated pulmonary benign metastasizing leiomyoma may result in the formation of cystic structures, destruction of lung parenchyma, and hemothorax and may cause respiratory failure. Surgical resection and hormonal therapy help prevent progression of this disease and provide an avenue for a cure.

  5. Oromotor Dyspraxia in Benign Childhood Epilepsy

    OpenAIRE

    J Gordon Millichap

    1989-01-01

    A six year old right handed boy with prolonged intermittent drooling, oromotor dyspraxia, and benign childhood epilepsy with centrotemporal spikes is reported from the Departments of Pediatrics and Neurology, Centre Hospitalier, Universitaire Vaudois, Lausanne, Switzerland.

  6. Genetics Home Reference: benign recurrent intrahepatic cholestasis

    Science.gov (United States)

    ... All Close All Description Benign recurrent intrahepatic cholestasis (BRIC) is characterized by episodes of liver dysfunction called ... a lack of appetite. A common feature of BRIC is the reduced absorption of fat in the ...

  7. Oral benign fibrous histiocytoma: two case reports

    OpenAIRE

    Menditti, Dardo; Laino, Luigi; Mezzogiorno, Antonio; Sava, Sara; Bianchi, Alexander; Caruso, Giovanni; Di Maio, Luigi; Baldi, Alfonso

    2009-01-01

    Fibrous histiocytoma is a benign soft tissue tumour arising as a fibrous mass everywhere in the human body. The involvement of the oral cavity is rare. We report two cases of benign fibrous histiocytoma that localized in the oral cavity. The clinical and histological features of the lesion are reported. Finally, a literature revision of this pathology at the level of the oral cavity is reported.

  8. Benign fibrous histiocytoma: A rare case involving jaw bone

    Directory of Open Access Journals (Sweden)

    Hitesh Shoor

    2015-01-01

    Full Text Available Benign fibrous histiocytoma (BFH is a soft tissue neoplasm which occurs mostly on the skin of extremities. BFH rarely occurs in bone and may affect femur, tibia, and pelvic bone. Jaw bone involvement is very unusual with only 11 cases reported till date. This report describes a case of BFH occurring in a 30-year-old female patient affecting left mandibular posterior region. Computed tomography revealed a well-defined expansile lytic lesion in the posterior mandible. Gross examination of the tumor revealed an admixture of fibroblasts and histiocytes in a fascicular and storiform pattern. Immunohistochemical staining was positive for CD68.

  9. Benign fibrous histiocytoma: A rare case involving jaw bone.

    Science.gov (United States)

    Shoor, Hitesh; Pai, Keerthilatha M; Shergill, Ankur Kaur; Kamath, Abhay Taranath

    2015-09-01

    Benign fibrous histiocytoma (BFH) is a soft tissue neoplasm which occurs mostly on the skin of extremities. BFH rarely occurs in bone and may affect femur, tibia, and pelvic bone. Jaw bone involvement is very unusual with only 11 cases reported till date. This report describes a case of BFH occurring in a 30-year-old female patient affecting left mandibular posterior region. Computed tomography revealed a well-defined expansile lytic lesion in the posterior mandible. Gross examination of the tumor revealed an admixture of fibroblasts and histiocytes in a fascicular and storiform pattern. Immunohistochemical staining was positive for CD68.

  10. Computer assisted interpretation of the human EEG: improving diagnostic efficiency and consistency in clinical reviews

    NARCIS (Netherlands)

    Lodder, Shaun Sandy

    2014-01-01

    Scalp electroencephalography (EEG) measures brain activity non-invasively by using electrodes on the scalp and capturing small electrical fluctuations caused by the firing of neurons. From these recordings, a clinical neurophysiologist can study the captured patterns and waveforms and determine if a

  11. Probabilistic M/EEG source imaging from sparse spatio-temporal event structure

    DEFF Research Database (Denmark)

    Stahlhut, Carsten; Attias, Hagai T.; Wipf, David

    While MEG and EEG source imaging methods have to tackle a severely ill-posed problem their success can be stated as their ability to constrain the solutions using appropriate priors. In this paper we propose a hierarchical Bayesian model facilitating spatio-temporal patterns through the use of bo...

  12. A Hierarchical Bayesian M/EEG Imaging Method Correcting for Incomplete Spatio-Temporal Priors

    DEFF Research Database (Denmark)

    Stahlhut, Carsten; Attias, Hagai T.; Sekihara, Kensuke;

    2013-01-01

    In this paper we present a hierarchical Bayesian model, to tackle the highly ill-posed problem that follows with MEG and EEG source imaging. Our model promotes spatiotemporal patterns through the use of both spatial and temporal basis functions. While in contrast to most previous spatio-temporal ...

  13. EEG based Autism Diagnosis Using Regularized Fisher Linear Discriminant Analysis

    Directory of Open Access Journals (Sweden)

    Mahmoud I. Kamel

    2012-04-01

    Full Text Available Diagnosis of autism is one of the difficult problems facing researchers. To reveal the discriminative pattern between autistic and normal children via electroencephalogram (EEG analysis is a big challenge. The feature extraction is averaged Fast Fourier Transform (FFT with the Regulated Fisher Linear Discriminant (RFLD classifier. Gaussinaty condition for the optimality of Regulated Fisher Linear Discriminant (RFLD has been achieved by a well-conditioned appropriate preprocessing of the data, as well as optimal shrinkage technique for the Lambda parameter. Winsorised Filtered Data gave the best result.

  14. Neural correlates of emotional responses to music: an EEG study.

    Science.gov (United States)

    Daly, Ian; Malik, Asad; Hwang, Faustina; Roesch, Etienne; Weaver, James; Kirke, Alexis; Williams, Duncan; Miranda, Eduardo; Nasuto, Slawomir J

    2014-06-24

    This paper presents an EEG study into the neural correlates of music-induced emotions. We presented participants with a large dataset containing musical pieces in different styles, and asked them to report on their induced emotional responses. We found neural correlates of music-induced emotion in a number of frequencies over the pre-frontal cortex. Additionally, we found a set of patterns of functional connectivity, defined by inter-channel coherence measures, to be significantly different between groups of music-induced emotional responses.

  15. Distribution entropy analysis of epileptic EEG signals.

    Science.gov (United States)

    Li, Peng; Yan, Chang; Karmakar, Chandan; Liu, Changchun

    2015-01-01

    It is an open-ended challenge to accurately detect the epileptic seizures through electroencephalogram (EEG) signals. Recently published studies have made elaborate attempts to distinguish between the normal and epileptic EEG signals by advanced nonlinear entropy methods, such as the approximate entropy, sample entropy, fuzzy entropy, and permutation entropy, etc. Most recently, a novel distribution entropy (DistEn) has been reported to have superior performance compared with the conventional entropy methods for especially short length data. We thus aimed, in the present study, to show the potential of DistEn in the analysis of epileptic EEG signals. The publicly-accessible Bonn database which consisted of normal, interictal, and ictal EEG signals was used in this study. Three different measurement protocols were set for better understanding the performance of DistEn, which are: i) calculate the DistEn of a specific EEG signal using the full recording; ii) calculate the DistEn by averaging the results for all its possible non-overlapped 5 second segments; and iii) calculate it by averaging the DistEn values for all the possible non-overlapped segments of 1 second length, respectively. Results for all three protocols indicated a statistically significantly increased DistEn for the ictal class compared with both the normal and interictal classes. Besides, the results obtained under the third protocol, which only used very short segments (1 s) of EEG recordings showed a significantly (p entropy algorithm. The capability of discriminating between the normal and interictal EEG signals is of great clinical relevance since it may provide helpful tools for the detection of a seizure onset. Therefore, our study suggests that the DistEn analysis of EEG signals is very promising for clinical and even portable EEG monitoring.

  16. The neurophysiological bases of EEG and EEG measurement: a review for the rest of us.

    Science.gov (United States)

    Jackson, Alice F; Bolger, Donald J

    2014-11-01

    A thorough understanding of the EEG signal and its measurement is necessary to produce high quality data and to draw accurate conclusions from those data. However, publications that discuss relevant topics are written for divergent audiences with specific levels of expertise: explanations are either at an abstract level that leaves readers with a fuzzy understanding of the electrophysiology involved, or are at a technical level that requires mastery of the relevant physics to understand. A clear, comprehensive review of the origin and measurement of EEG that bridges these high and low levels of explanation fills a critical gap in the literature and is necessary for promoting better research practices and peer review. The present paper addresses the neurophysiological source of EEG, propagation of the EEG signal, technical aspects of EEG measurement, and implications for interpretation of EEG data.

  17. EEG, alpha waves and coherence

    Science.gov (United States)

    Ascolani, Gianluca

    This thesis addresses some theoretical issues generated by the results of recent analysis of EEG time series proving the brain dynamics are driven by abrupt changes making them depart from the ordinary Poisson condition. These changes are renewal, unpredictable and non-ergodic. We refer to them as crucial events. How is it possible that this form of randomness be compatible with the generation of waves, for instance alpha waves, whose observation seems to suggest the opposite view the brain is characterized by surprisingly extended coherence? To shed light into this apparently irretrievable contradiction we propose a model based on a generalized form of Langevin equation under the influence of a periodic stimulus. We assume that there exist two different forms of time, a subjective form compatible with Poisson statistical physical and an objective form that is accessible to experimental observation. The transition from the former to the latter form is determined by the brain dynamics interpreted as emerging from the cooperative interaction among many units that, in the absence of cooperation would generate Poisson fluctuations. We call natural time the brain internal time and we make the assumption that in the natural time representation the time evolution of the EEG variable y(t) is determined by a Langevin equation perturbed by a periodic process that in this time representation is hardly distinguishable from an erratic process. We show that the representation of this random process in the experimental time scale is characterized by a surprisingly extended coherence. We show that this model generates a sequence of damped oscillations with a time behavior that is remarkably similar to that derived from the analysis of real EEG's. The main result of this research work is that the existence of crucial events is not incompatible with the alpha wave coherence. In addition to this important result, we find another result that may help our group, or any other research

  18. Changes in EEG pre and post awakening.

    Science.gov (United States)

    Voss, Ursula

    2010-01-01

    This chapter is concerned with behavioral and electrophysiologic evidence of awakenings. Awakenings are understood here as a state change from sleeping to waking. We will discuss the methodological issues and the problem of properly defining an awakening. With regard to phenomena preceding an awakening, we will look at arousals and compare background to event-related activity in the electroencephalography (EEG). As arousability varies between and within species, the relevant EEG correlates of this variability are described. Concerning EEG changes following an awakening, the discussion focuses on sleep inertia effects.

  19. Challenges in pediatric video-EEG monitoring.

    Science.gov (United States)

    Sullivan, Joseph E; Corcoran-Donnelly, Maureen; Dlugos, Dennis J

    2007-06-01

    Video-EEG (VEEG) monitoring is now commonly used in children. When designing a pediatric video-EEG monitoring unit, there are many issues that need to be considered to take full advantage of this technology. Topics such as the physical layout of the VEEG unit, VEEG equipment, networking, staffing, and lines of communication regarding referrals and VEEG interpretation must be considered. Only after careful consideration of these issues, can video-EEG monitoring be successful and provide safe, state of the art clinical care in an efficient manner.

  20. Prediction of Synchrostate Transitions in EEG Signals Using Markov Chain Models

    CERN Document Server

    Jamal, Wasifa; Oprescu, Ioana-Anastasia; Maharatna, Koushik

    2014-01-01

    This paper proposes a stochastic model using the concept of Markov chains for the inter-state transitions of the millisecond order quasi-stable phase synchronized patterns or synchrostates, found in multi-channel Electroencephalogram (EEG) signals. First and second order transition probability matrices are estimated for Markov chain modelling from 100 trials of 128-channel EEG signals during two different face perception tasks. Prediction accuracies with such finite Markov chain models for synchrostate transition are also compared, under a data-partitioning based cross-validation scheme.

  1. Biogas plants in EEG. 3. new rev. and enl. ed.; Biogasanlagen im EEG

    Energy Technology Data Exchange (ETDEWEB)

    Loibl, Helmut; Maslaton, Martin; Bredow, Hartwig von; Walter, Rene (eds.)

    2013-06-01

    EEG 2012 is a complete revision for new EEG plants whereby the previous requirements of the EEG 2009 can be maintained for the existing plants. The authors of the book under consideration fully focus on the splitting into two different legal systems and the implications. It describes possibilities of solution for problems from the daily practice. The book provides a complete commentation of the biomass ordinance as well as the statements on the connection to the gas grid of biomethane plants.

  2. Clinical utility of early amplitude integrated EEG in monitoring term newborns at risk of neurological injury

    Directory of Open Access Journals (Sweden)

    Paulina A. Toso

    2014-04-01

    Full Text Available OBJECTIVE: to test the clinical utility of an early amplitude-integrated electroencephalography (aEEG to predict short-term neurological outcome in term newborns at risk of neurology injury. METHODS: this was a prospective, descriptive study. The inclusion criteria were neonatal encephalopathy, neurologic disturbances, and severe respiratory distress syndrome. Sensitivity, specificity, positive and negative predictive values, and likelihood ratio (LR were calculated. Clinical and demographic data were analyzed. Neurological outcome was defined as the sum of clinical, electroimaging, and neuroimaging findings. RESULTS: ten of the 21 monitored infants (48% presented altered short-term neurologic outcome. The aEEG had 90% sensitivity, 82% specificity, 82% positive predictive value, and 90% negative predictive value. The positive LR was 4.95, and the negative LR was 0.12. In three of 12 (25% encephalopathic infants, the aEEG allowed for a better definition of the severity of their condition. Seizures were detected in eight infants (38%, all subclinical at baseline, and none had a normal aEEG background pattern. The status of three infants (43% evolved and required two or more drugs for treatment. CONCLUSIONS: in infants with encephalopathy or other severe illness, aEEG disturbances occur frequently. aEEG provided a better classification of the severity of encephalopathy, detected early subclinical seizures, and allowed for monitoring of the response to treatment. aEEG was a useful tool at the neonatal intensive care unit for predicting poor short-term neurological outcomes for all sick newborn.

  3. Stroboscopic findings in patients with benign laryngeal lesions: a brief report

    Directory of Open Access Journals (Sweden)

    S Azimian

    2012-11-01

    Full Text Available Background: Laryngeal videostroboscopy is an important noninvasive diagnostic tool in patients with dysphonia. More than 50% of patients with dysphonia have a benign laryngeal lesion on vocal fold examination. The aim of this study was to evaluate patients with benign laryngeal lesions by videostroboscopy.Methods: This cross-sectional study was done on 159 patients with dysphonia in Amiralam Hospital in Tehran, Iran during 2006-2007. All the patients underwent stroboscopic examination of the vocal folds, including their movement. We also evaluated the patients for mucosal status, mucosal wave and patterns of glottal closure.Results: Eighty-two patients participating in the study were female and 77 were male. Reflux laryngitis and muscle tension dysphonia were the most observed disorders in the patient population. Patients with sulcus vocalis and intracordal cysts had the worst mucosal wave patterns.Conclusion: Laryngeal videostroboscopy is a useful tool for the diagnosis and treatment planning in patients with benign laryngeal lesions.

  4. Elastography Evaluation of Benign Thyroid Nodules in Patients Affected by Hashimoto’s Thyroiditis

    Directory of Open Access Journals (Sweden)

    Carlo Cappelli

    2015-01-01

    Full Text Available The aim of the present prospective study was to evaluate the predictive value of elastography in benign thyroid nodules of patients affected by Hashimoto’s thyroiditis (HT. From January 2011 to January 2012, 242 nodules in patients affected by HT were submitted to fine needle aspiration cytology (FNAC. All of the patients underwent sonography and elastography performed before FNAC. 230 (95% nodules were benign, 8 papillary cancers, and 4 follicular lesions. Score 1 was found in 79.1% of benign lesions (sensitivity 79.1%; specificity 66.7%; PPV 97.8%; NPV 14.3%; accuracy 78.5%; p<0.05. In order to evaluate the outcome of thyroid ultrasound echogenicity in relation to elastography features of nodule(s, all the patients with benign nodules were stratified according to their hypoechoic pattern of thyroid (mild-moderate and severe. Following stratification score 1 was found in 84.2% of benign nodules (sensitivity 75.0%; specificity 88.9%; PPV 27.3%; NPV 98.4%; accuracy 88.2%; p<0.0001 of patients with a mild-moderate ultrasound thyroid hypoechogenicity, whereas it was found in 60% of benign nodules (p=0.715 of patients with a marked thyroid hypoechogenicity. Elastography appears to have limited value in detecting thyroid cancer in patients affected by Hashimoto’s thyroiditis with severe hypoechoic thyroid tissue.

  5. Clinical characteristics of patients with benign nonlesional temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Kim J

    2016-07-01

    Full Text Available Jiyeon Kim,1 Seong Hoon Kim,2 Sung Chul Lim,2 Woojun Kim,2 Young-Min Shon3 1Department of Neurology, Korea University Ansan Hospital, College of Medicine, Korea University, Ansan, 2Department of Neurology, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seocho-gu, 3Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea Purpose: To evaluate the evolution of nonlesional temporal lobe epilepsy (TLE-NL in patients treated exclusively with antiepileptic drugs and to elucidate clinical phenotypes related to the prognosis of these patients.Methods: Clinical, radiological, and electroencephalographic (EEG findings in 84 patients with TLE-NL were reviewed. A good response group (GRG and a poor response group (PRG were defined if the duration of their seizure-free period was >1 year, or <1 year, respectively.Results: There were 46 (54.8% patients in the GRG and 38 (45.2% patients in the PRG. The number of antiepileptic drugs administered was significantly lower in the GRG than that in the PRG (1.3±0.8 vs 2.8±1.0, respectively; P<0.05. The GRG had a significantly older age of onset than the PRG and a lower occurrence of initial precipitating events, such as febrile seizures, central nervous system infection, and head trauma (P<0.05. The prevalence of EEG abnormality, presence of aura, generalized seizures, and automatism was less frequently observed in the GRG (P<0.05. Multivariate analysis showed that the presence of automatism and initial precipitating events were significantly associated with a poor prognosis (P<0.05.Conclusion: In contrast to the commonly assumed intractability of TLE, we found that more than 54% of patients with TLE-NL achieved a long seizure-free period. Older age at onset of TLE-NL was associated with a better prognosis. However, the presence of automatism and initial precipitating events were related to a poor prognosis. Future prospective

  6. Generic Misalignment Aberration Patterns and the Subspace of Benign Misalignment

    CERN Document Server

    Schechter, Paul L

    2012-01-01

    Q1: Why deploy N wavefront sensors on a three mirror anastigmat (TMA) and not N + 1? Q2: Why measure M Zernike coefficients and not M + 1? Q3: Why control L rigid body degrees of freedom (total) on the secondary and tertiary and not L + 1? The usual answer: "We did a lot of ray tracing and N,M, and L seemed OK." We show how straightforward results from aberration theory may be used to address these questions. We consider, in particular, the case of a three mirror anastigmat.

  7. Reference layer adaptive filtering (RLAF) for EEG artifact reduction in simultaneous EEG-fMRI

    Science.gov (United States)

    Steyrl, David; Krausz, Gunther; Koschutnig, Karl; Edlinger, Günter; Müller-Putz, Gernot R.

    2017-04-01

    Objective. Simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) combines advantages of both methods, namely high temporal resolution of EEG and high spatial resolution of fMRI. However, EEG quality is limited due to severe artifacts caused by fMRI scanners. Approach. To improve EEG data quality substantially, we introduce methods that use a reusable reference layer EEG cap prototype in combination with adaptive filtering. The first method, reference layer adaptive filtering (RLAF), uses adaptive filtering with reference layer artifact data to optimize artifact subtraction from EEG. In the second method, multi band reference layer adaptive filtering (MBRLAF), adaptive filtering is performed on bandwidth limited sub-bands of the EEG and the reference channels. Main results. The results suggests that RLAF outperforms the baseline method, average artifact subtraction, in all settings and also its direct predecessor, reference layer artifact subtraction (RLAS), in lower (<35 Hz) frequency ranges. MBRLAF is computationally more demanding than RLAF, but highly effective in all EEG frequency ranges. Effectivity is determined by visual inspection, as well as root-mean-square voltage reduction and power reduction of EEG provided that physiological EEG components such as occipital EEG alpha power and visual evoked potentials (VEP) are preserved. We demonstrate that both, RLAF and MBRLAF, improve VEP quality. For that, we calculate the mean-squared-distance of single trial VEP to the mean VEP and estimate single trial VEP classification accuracies. We found that the average mean-squared-distance is lowest and the average classification accuracy is highest after MBLAF. RLAF was second best. Significance. In conclusion, the results suggests that RLAF and MBRLAF are potentially very effective in improving EEG quality of simultaneous EEG-fMRI. Highlights We present a new and reusable reference layer cap prototype for simultaneous EEG-fMRI We

  8. Contrast-enhanced ultrasound is helpful in the differentiation of malignant and benign breast lesions

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Hongjia; Xu Rong; Ouyang Qiufang [Department of Ultrasound, The Second Affiliated Hospital of Fujian University of Traditional Chinese Medicine, Fuzhou (China); Chen Lidian [Fujian University of Traditional Chinese Medicine, Fuzhou (China)], E-mail: lidianchen87@yahoo.com; Dong Baowei [Department of Ultrasound, PLA 301 General Hospital, Beijing (China); Huihua Ye [Department of Ultrasound, The Second Affiliated Hospital of Fujian University of Traditional Chinese Medicine, Fuzhou (China)

    2010-02-15

    Objective: To evaluate the significance of contrast-enhanced ultrasound (CEUS) examination in differential diagnosis of malignant and benign breast lesions. Methods: Seventy-one patients with seventy-six breast tumors are selected randomly. CEUS examinations were performed before and after bolus injection of the contrast agent SonoVue (Bracco, Milan, Italy). Specific sonographic quantification software, Qontrast, was adopted to determine the morphology of vessels. Wash-in and wash-out parameters of each lesion were assessed for both procedures. Results: The final histopathological findings distinguished 45 malignant and 31 benign from all of the lesions. Following SonoVue administration different perfusion phases could be identified: early (0-1 min), mid (1-4 min) and late (4-6 min) phases. In the early phase, CEUS identified 91.1% of malignant tumors characterized by a claw-shaped enhancement, while 83.9% of benign tumors had a homogeneous enhancement, with a statistically significant difference between the two enhancement patterns ({chi}{sup 2} = 43.16, P < 0.01). Moreover, contrast medium persistence in the late phase was helpful in the identification of benign and malignant tumors ({chi}{sup 2} = 46.88, P < 0.01): contrast medium was present in 88.9% of malignant tumors, while in only 9.7% of the benign tumors. The study showed that various parametric imaging color maps for peak intensity and time to peak were mostly suggestive of malignancy, while quite uniform peak intensity and time to peak of color maps were the characteristic of benign tumors. The study also found that malignant lesions presented with a higher maximum intensity signal than benign ones (P < 0.05) on the time-intensity curves. Conclusions: CEUS cooperating with conventional US shows improved accuracy in differentiating between malignant and benign breast tumors. It could be a reliable diagnostic method of breast lesions.

  9. EEG correlates of emotions in dream narratives from typical young adults and individuals with autistic spectrum disorders.

    Science.gov (United States)

    Daoust, Anne-Marie; Lusignan, Félix-Antoine; Braun, Claude M J; Mottron, Laurent; Godbout, Roger

    2008-03-01

    The relationship between emotional dream content and Alpha and Beta REM sleep EEG activity was investigated in typical individuals and in Autistic Spectrum Disorders (ASD). Dream narratives of persons with ASD contained fewer emotional elements. In both groups, emotions correlated positively with slow Alpha (8.0-10.0 Hz) spectral power over parieto-occipital and left central regions, as well as with a right occipital EEG asymmetry. Slow Alpha activity in ASD individuals was lower over midline and parasagittal areas and higher over lateral areas compared to controls. Both groups displayed a right-biased slow Alpha activity for midparietal and occipital (significantly higher in control) sites. Results indicate that Alpha EEG activity may represent a neurophysiological substrate associated with emotional dream content. Distinctive Alpha EEG patterns and asymmetries suggest that dream generation implies different brain connectivity in ASD.

  10. EEG alpha frequency correlates of burnout and depression: The role of gender.

    Science.gov (United States)

    Tement, Sara; Pahor, Anja; Jaušovec, Norbert

    2016-02-01

    EEG alpha frequency band biomarkers of depression are widely explored. Due to their trait-like features, they may help distinguish between depressive and burnout symptomatology, which is often referred to as "work-related depression". The present correlational study strived to examine whether individual alpha frequency (IAF), power, and coherence in the alpha band can provide evidence for establishing burnout as a separate diagnostic entity. Resting EEG (eyes closed) was recorded in 117 individuals (42 males). In addition, the participants filled-out questionnaires of burnout and depression. Regression analyses highlighted the differential value of IAF and power in predicting burnout and depression. IAF was significantly related to depressive symptomatology, whereas power was linked mostly to burnout. Moreover, seven out of twelve interactions between EEG indicators and gender were significant. Connectivity patterns were significant for depression displaying gender-related differences. The results offer tentative support for establishing burnout as a separate clinical syndrome.

  11. Resting State EEG-based biometrics for individual identification using convolutional neural networks.

    Science.gov (United States)

    Lan Ma; Minett, James W; Blu, Thierry; Wang, William S-Y

    2015-08-01

    Biometrics is a growing field, which permits identification of individuals by means of unique physical features. Electroencephalography (EEG)-based biometrics utilizes the small intra-personal differences and large inter-personal differences between individuals' brainwave patterns. In the past, such methods have used features derived from manually-designed procedures for this purpose. Another possibility is to use convolutional neural networks (CNN) to automatically extract an individual's best and most unique neural features and conduct classification, using EEG data derived from both Resting State with Open Eyes (REO) and Resting State with Closed Eyes (REC). Results indicate that this CNN-based joint-optimized EEG-based Biometric System yields a high degree of accuracy of identification (88%) for 10-class classification. Furthermore, rich inter-personal difference can be found using a very low frequency band (0-2Hz). Additionally, results suggest that the temporal portions over which subjects can be individualized is less than 200 ms.

  12. On the Existence of Synchrostates in Multichannel EEG Signals during Face-perception Tasks

    CERN Document Server

    Jamal, Wasifa; Maharatna, Koushik; Apicella, Fabio; Chronaki, Georgia; Sicca, Federico; Cohen, David; Muratori, Filippo

    2016-01-01

    Phase synchronisation in multichannel EEG is known as the manifestation of functional brain connectivity. Traditional phase synchronisation studies are mostly based on time average synchrony measures hence do not preserve the temporal evolution of the phase difference. Here we propose a new method to show the existence of a small set of unique phase synchronised patterns or "states" in multi-channel EEG recordings, each "state" being stable of the order of ms, from typical and pathological subjects during face perception tasks. The proposed methodology bridges the concepts of EEG microstates and phase synchronisation in time and frequency domain respectively. The analysis is reported for four groups of children including typical, Autism Spectrum Disorder (ASD), low and high anxiety subjects - a total of 44 subjects. In all cases, we observe consistent existence of these states - termed as synchrostates - within specific cognition related frequency bands (beta and gamma bands), though the topographies of these...

  13. Robot-Aided Upper-Limb Rehabilitation Based on Motor Imagery EEG

    Directory of Open Access Journals (Sweden)

    Baoguo Xu

    2011-09-01

    Full Text Available Stroke is a leading cause of disability worldwide. In this paper, a novel robot‐assisted rehabilitation system based on motor imagery electroencephalography (EEG is developed for regular training of neurological rehabilitation for upper limb stroke patients. Firstly, three‐dimensional animation was used to guide the patient image the upper limb movement and EEG signals were acquired by EEG amplifier. Secondly, eigenvectors were extracted by harmonic wavelet transform (HWT and linear discriminant analysis (LDA classifier was utilized to classify the pattern of the left and right upper limb motor imagery EEG signals. Finally, PC triggered the upper limb rehabilitation robot to perform motor therapy and gave the virtual feedback. Using this robot‐assisted upper limb rehabilitation system, the patientʹs EEG of upper limb movement imagination is translated to control rehabilitation robot directly. Consequently, the proposed rehabilitation system can fully explore the patientʹs motivation and attention and directly facilitate upper limb post‐stroke rehabilitation therapy. Experimental results on unimpaired participants were presented to demonstrate the feasibility of the rehabilitation system. Combining robot‐assisted training with motor imagery‐ based BCI will make future rehabilitation therapy more effective. Clinical testing is still required for further proving this assumption.

  14. Recognition of Words from the EEG Laplacian

    CERN Document Server

    de Barros, J Acacio; de Mendonça, J P R F; Suppes, P

    2012-01-01

    Recent works on the relationship between the electro-encephalogram (EEG) data and psychological stimuli show that EEG recordings can be used to recognize an auditory stimulus presented to a subject. The recognition rate is, however, strongly affected by technical and physiological artifacts. In this work, subjects were presented seven auditory simuli in the form of English words (first, second, third, left, right, yes, and no), and the time-locked electric field was recorded with a 64 channel Neuroscan EEG system. We used the surface Laplacian operator to eliminate artifacts due to sources located at regions far from the electrode. Our intent with the Laplacian was to improve the recognition rates of auditory stimuli from the electric field. To compute the Laplacian, we used a spline interpolation from spherical harmonics. The EEG Laplacian of the electric field were average over trials for the same auditory stimulus, and with those averages we constructed prototypes and test samples. In addition to the Lapla...

  15. Vigilance Degree Computing Based on EEG

    Directory of Open Access Journals (Sweden)

    Zhenzhong Zhan

    2013-09-01

    Full Text Available In daily life, lots of work need people maintain higher attention or vigilance. In the early study of vigilance, blink frequency, the impedance of skin, body temperature and blood pressure and other physiological signals was used to estimate the vigilance. EEG signal can more directly reflect the brain's activity than other physiological signals, and EEG signal have a higher time resolution. In this paper, ERP component and different frequencies of EEG were used to analyze the alert state, according to this study, in the ERP components, N170 can be a good representation of the degree of fatigue of the subject; Through the 10 subjects EEG frequency distribution analysis, and according to the formula defined in this paper, the vigilance degree of this ten subjects was calculated.  

  16. Bone tumors with an associated pathologic fracture: Differentiation between benign and malignant status using radiologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Ji Hyun; Lee, In Sook; Song, You Seon [Pusan National University School of Medicine, Pusan National University Hospital, Busan (Korea, Republic of); Kim, Jeung Il [Dept. of Radiology, Yeungnam University College of Medicine, Yeungnam University Medical Center, Daegu (Korea, Republic of); Lee, Moon Sung [Dept. of Radiology, Keimyung University College of Medicine, Dongsan Medical Center, Daegu (Korea, Republic of); Lee, Young Hwan [Dept. of Radiology, Catholic University of Daegu College of Medicine, Daegu Catholic University Hospital, Daegu (Korea, Republic of); Song, Jong Woon [Dept. of Radiology, Inje University College of Medicine, Haeundae Paik Hospital, Busan (Korea, Republic of)

    2015-10-15

    To determine whether benign and malignant bone tumors with associated pathologic fractures can be differentiated using radiologic findings. Seventy-eight patients (47 men and 31 women, age range: 1-93 years) with a bone tumor and an associated pathologic fracture from 2004 to 2013 constituted the retrospective study cohort. The tumor size, margin, and enhancement patterns; the presence of sclerotic margin, the peritumoral bone marrow, soft tissue edema, extra-osseous soft tissue mass, intratumoral cystic/hemorrhagic/necrotic regions, mineralization/sclerotic regions, periosteal reaction and its appearance; and cortical change and its appearance were evaluated on all images. Differences between the imaging characteristics of malignant and benign pathologic fractures were compared using Pearson's chi-square test and the 2-sample t-test. There were 22 benign and 56 malignant bone tumors. Some factors were found to significantly differentiate between benign and malignant tumors; specifically, ill-defined tumor margin, the presence of sclerotic tumor margin and an extra-osseous soft tissue mass, the absence of cystic/necrotic/hemorrhagic portions in a mass, the homogeneous enhancement pattern, and the presence of a displaced fracture and of underlying cortical change were suggestive of malignant pathologic fractures. Some imaging findings were helpful for differentiating between benign and malignant pathologic fractures.

  17. Scaling Property in the Alpha Predominant EEG

    CERN Document Server

    Lin, D C; Kwan, H; Lin, Der Chyan; Sharif, Asif; Kwan, Hon

    2004-01-01

    The $\\alpha$ predominant electroencephalographic (EEG) recording of the human brain during eyes open and closed is studied using the zero-crossing time statistics. A model is presented to demonstrate and compare the key characteristics of the brain state. We found the zero-crossing time statistic is more accurate than the power spectral analysis and the detrend fluctuation analysis. Our results indicate different EEG fractal scaling in eyes closed and open for individuals capable of strong $\\alpha$ rhythm.

  18. Resting State EEG in Children With Learning Disabilities: An Independent Component Analysis Approach.

    Science.gov (United States)

    Jäncke, Lutz; Alahmadi, Nsreen

    2016-01-01

    In this study, the neurophysiological underpinnings of learning disabilities (LD) in children are examined using resting state EEG. We were particularly interested in the neurophysiological differences between children with learning disabilities not otherwise specified (LD-NOS), learning disabilities with verbal disabilities (LD-Verbal), and healthy control (HC) children. We applied 2 different approaches to examine the differences between the different groups. First, we calculated theta/beta and theta/alpha ratios in order to quantify the relationship between slow and fast EEG oscillations. Second, we used a recently developed method for analyzing spectral EEG, namely the group independent component analysis (gICA) model. Using these measures, we identified substantial differences between LD and HC children and between LD-NOS and LD-Verbal children in terms of their spectral EEG profiles. We obtained the following findings: (a) theta/beta and theta/alpha ratios were substantially larger in LD than in HC children, with no difference between LD-NOS and LD-Verbal children; (b) there was substantial slowing of EEG oscillations, especially for gICs located in frontal scalp positions, with LD-NOS children demonstrating the strongest slowing; (c) the estimated intracortical sources of these gICs were mostly located in brain areas involved in the control of executive functions, attention, planning, and language; and (d) the LD-Verbal children demonstrated substantial differences in EEG oscillations compared with LD-NOS children, and these differences were localized in language-related brain areas. The general pattern of atypical neurophysiological activation found in LD children suggests that they suffer from neurophysiological dysfunction in brain areas involved with the control of attention, executive functions, planning, and language functions. LD-Verbal children also demonstrate atypical activation, especially in language-related brain areas. These atypical

  19. Prognostic value of electroencephalography (EEG) after out-of-hospital cardiac arrest in successfully resuscitated patients used in daily clinical practice

    DEFF Research Database (Denmark)

    Søholm, Helle; Kjær, Troels Wesenberg; Kjaergaard, Jesper;

    2014-01-01

    were used. EEG reports were analysed according to the 2012 American Clinical Neurophysiology Society's guidelines. RESULTS: A total of 1076 patients were included, and EEG was performed in 20% (n=219) with a median of 3(IQR 2-4) days after OHCA. Rhythmic Delta Activity (RDA) was found in 71 patients......-suppression in 17 (8%) patients. A favourable EEG pattern (reactivity, favourable background frequency and RDA) was independently associated with reduced mortality with hazard ratio (HR) 0.43 (95%CI: 0.24-0.76), p=0.004 (false positive rate: 31%) and a non-favourable EEG pattern (no reactivity, unfavourable...... such as Rhythmic Delta Activity (RDA) seem to be associated with a better prognosis, whereas suppressed voltage and burst-suppression patterns were associated with poor prognosis....

  20. Analysis of EEG activity during sleep - brain hemisphere symmetry of two classes of sleep spindles

    Science.gov (United States)

    Smolen, Magdalena M.

    2009-01-01

    This paper presents automatic analysis of some selected human electroencephalographic patterns during deep sleep using the Matching Pursuit (MP) algorithm. The periodicity of deep sleep EEG patterns was observed by calculating autocorrelation functions of their percentage contributions. The study confirmed the increasing trend of amplitude-weighted average frequency of sleep spindles from frontal to posterior derivations. The dominant frequencies from the left and the right brain hemisphere were strongly correlated.

  1. EEG in Sarcoidosis Patients Without Neurological Findings.

    Science.gov (United States)

    Bilgin Topçuoğlu, Özgür; Kavas, Murat; Öztaş, Selahattin; Arınç, Sibel; Afşar, Gülgün; Saraç, Sema; Midi, İpek

    2017-01-01

    Sarcoidosis is a multisystem granulomatous disease affecting nervous system in 5% to 10% of patients. Magnetic resonance imaging (MRI) is accepted as the most sensitive method for detecting neurosarcoidosis. However, the most common findings in MRI are the nonspecific white matter lesions, which may be unrelated to sarcoidosis and can occur because of hypertension, diabetes mellitus, smoking, and other inflammatory or infectious disorders, as well. Autopsy studies report more frequent neurological involvement than the ante mortem studies. The aim of this study is to assess electroencephalography (EEG) in sarcoidosis patients without neurological findings in order to display asymptomatic neurological dysfunction. We performed EEG on 30 sarcoidosis patients without diagnosis of neurosarcoidosis or prior neurological comorbidities. Fourteen patients (46.7%) showed intermittant focal and/or generalized slowings while awake and not mentally activated. Seven (50%) of these 14 patients with EEG slowings had nonspecific white matter changes while the other half showed EEG slowings in the absence of MRI changes. We conclude that EEG slowings, when normal variants (psychomotor variant, temporal theta of elderly, frontal theta waves) are eliminated, may be an indicator of dysfunction in brain activity even in the absence of MRI findings. Hence, EEG may contribute toward detecting asymptomatic neurological dysfunction or probable future neurological involvement in sarcoidosis patients.

  2. Cognitive neuroscience of creativity: EEG based approaches.

    Science.gov (United States)

    Srinivasan, Narayanan

    2007-05-01

    Cognitive neuroscience of creativity has been extensively studied using non-invasive electrical recordings from the scalp called electroencephalograms (EEGs) and event related potentials (ERPs). The paper discusses major aspects of performing research using EEG/ERP based experiments including the recording of the signals, removing noise, estimating ERP signals, and signal analysis for better understanding of the neural correlates of processes involved in creativity. Important factors to be kept in mind to record clean EEG signal in creativity research are discussed. The recorded EEG signal can be corrupted by various sources of noise and methodologies to handle the presence of unwanted artifacts and filtering noise are presented followed by methods to estimate ERPs from the EEG signals from multiple trials. The EEG and ERP signals are further analyzed using various techniques including spectral analysis, coherence analysis, and non-linear signal analysis. These analysis techniques provide a way to understand the spatial activations and temporal development of large scale electrical activity in the brain during creative tasks. The use of this methodology will further enhance our understanding the processes neural and cognitive processes involved in creativity.

  3. Benign multicystic peritoneal mesothelioma: a case report

    Directory of Open Access Journals (Sweden)

    Papapaulou Leonidas

    2010-11-01

    Full Text Available Abstract Introduction We report the case of a patient with a benign multicystic peritoneal mesothelioma and describe its appearance on computed tomography scans and ultrasonography, in correlation with gross clinical and pathological findings. Case presentation A 72-year-old Caucasian woman presented to our emergency department with acute abdomen signs and symptoms. A clinical examination revealed a painful palpable mass in her left abdomen. Abdominal ultrasonography and computed tomography demonstrated the presence of a large cystic mass in her left upper abdomen, adjacent to her left hemidiaphragm. The lower border of the mass extended to the upper margin of her pelvis. A complete resection of the lesion was performed. Pathological analysis showed a benign multicystic peritoneal mesothelioma. Conclusions Benign multicystic peritoneal mesothelioma is a rare lesion with a non-specific appearance on imaging. Its diagnosis always requires pathological analysis.

  4. Recursive approach of EEG-segment-based principal component analysis substantially reduces cryogenic pump artifacts in simultaneous EEG-fMRI data.

    Science.gov (United States)

    Kim, Hyun-Chul; Yoo, Seung-Schik; Lee, Jong-Hwan

    2015-01-01

    Electroencephalography (EEG) data simultaneously acquired with functional magnetic resonance imaging (fMRI) data are preprocessed to remove gradient artifacts (GAs) and ballistocardiographic artifacts (BCAs). Nonetheless, these data, especially in the gamma frequency range, can be contaminated by residual artifacts produced by mechanical vibrations in the MRI system, in particular the cryogenic pump that compresses and transports the helium that chills the magnet (the helium-pump). However, few options are available for the removal of helium-pump artifacts. In this study, we propose a recursive approach of EEG-segment-based principal component analysis (rsPCA) that enables the removal of these helium-pump artifacts. Using the rsPCA method, feature vectors representing helium-pump artifacts were successfully extracted as eigenvectors, and the reconstructed signals of the feature vectors were subsequently removed. A test using simultaneous EEG-fMRI data acquired from left-hand (LH) and right-hand (RH) clenching tasks performed by volunteers found that the proposed rsPCA method substantially reduced helium-pump artifacts in the EEG data and significantly enhanced task-related gamma band activity levels (p=0.0038 and 0.0363 for LH and RH tasks, respectively) in EEG data that have had GAs and BCAs removed. The spatial patterns of the fMRI data were estimated using a hemodynamic response function (HRF) modeled from the estimated gamma band activity in a general linear model (GLM) framework. Active voxel clusters were identified in the post-/pre-central gyri of motor area, only from the rsPCA method (uncorrected p<0.001 for both LH/RH tasks). In addition, the superior temporal pole areas were consistently observed (uncorrected p<0.001 for the LH task and uncorrected p<0.05 for the RH task) in the spatial patterns of the HRF model for gamma band activity when the task paradigm and movement were also included in the GLM.

  5. BENIGN BREAST DISEASE: OUR INSTITUTIONAL EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Harish Kumar

    2014-11-01

    Full Text Available BACKGROUND AND OBJECTIVES: In this modern era of change in dietary habits, life style and increased awareness about the self-breast examination, the rate of detection of breast lump is on increasing trend. Due to its enormous anatomical and physiological changes during different phases of life, breast diseases are not uncommon. The benign conditions however are also associated with morbidity and are of great concern to the patient. This study was carried out to compare the age distribution and proportion of various benign breast tumors, taking into account the various factors associated with them. A correlation of clinical and histopathological diagnosis was drawn and thus the specificity of clinical diagnosis. METHODS: Prospective review of 50 patients from General Surgery department, who are found to have benign breast tumors on clinico-pathological examination, Bowring and Lady Curzon Hospitals, attached to Bangalore Medical College & Research Institute, Bangalore selected during the period from October 2011 to April 2014 on random basis. Post-operative follow up done to note the complications both in hospital and after discharge. RESULTS: Patients predominantly presented with lump in breast were fibroadenoma and fibrocystic disease. Ductal papilloma, phyllodes tumor and lipoma were also encountered. All patients underwent FNAC. Treatment was mostly surgical in the form of excision, simple mastectomy, microdochotomy and wide local excision. All the specimens were subjected to histopathological examination. Using clinical diagnosis, FNAC and histopathology increased the accuracy of diagnosis. Cases followed up and no recurrence was found. CONCLUSIONS: Commonest benign breast tumor found was Fibroadenoma (78%. Majority of the patients were in the active reproductive age group. Fibroadenoma was more common in 2nd decade of life, whereas fibrocystic disease found in 3rd decade. Majority of benign breast lesions presented with painless lump. FNAC

  6. Hippocampal EEG and behaviour in dog. II. Hippocampal EEG correlates with elementary motor acts

    NARCIS (Netherlands)

    Arnolds, D.E.A.T.; Lopes da Silva, F.H.; Aitink, J.W.; Kamp, A.

    1979-01-01

    A positive correlation has been shown between the speed of forced stepping on a conveyor belt and the amplitude and frequency of the concomitant hippocampal EEG. Significant modulation in the spectral properties of the dog's hippocampal EEG has been found in relation to 3 elementary motor acts: ste

  7. Radiofrequency ablation for benign thyroid nodules.

    Science.gov (United States)

    Bernardi, S; Stacul, F; Zecchin, M; Dobrinja, C; Zanconati, F; Fabris, B

    2016-09-01

    Benign thyroid nodules are an extremely common occurrence. Radiofrequency ablation (RFA) is gaining ground as an effective technique for their treatment, in case they become symptomatic. Here we review what are the current indications to RFA, its outcomes in terms of efficacy, tolerability, and cost, and also how it compares to the other conventional and experimental treatment modalities for benign thyroid nodules. Moreover, we will also address the issue of treating with this technique patients with cardiac pacemakers (PM) or implantable cardioverter-defibrillators (ICD), as it is a rather frequent occurrence that has never been addressed in detail in the literature.

  8. The decline of hysterectomy for benign disease.

    LENUS (Irish Health Repository)

    Horgan, R P

    2012-01-31

    Hysterectomy is one of the most common gynaecological surgical procedures performed but there appears to be a decline in the performance of this procedure in Ireland in recent times. We set out to establish the extent of the decline of hysterectomy and to explore possible explanations. Data for hysterectomy for benign disease from Ireland was obtained from the Hospital In-Patient Enquiry Scheme (HIPE) section of the Economic and Social Research Institute for the years 1999 to 2006. The total number of hysterectomies performed for benign disease showed a consistent decline during this time. There was a 36% reduction in the number of abdominal hysterectomy procedures performed.

  9. Benign cephalic histiocytosis: report of four cases.

    Science.gov (United States)

    de Luna, M L; Glikin, I; Golberg, J; Stringa, S; Schroh, R; Casas, J

    1989-09-01

    We cared for four patients with benign cephalic histiocytosis, a self-healing non-X, nonlipid cutaneous histiocytosis of children. The age of onset of the disease was 5 to 9 months, with papules and erythematous macules involving the head (mainly the cheeks), and posterior spread to the trunk and limbs in three patients. Microscopic examination of skin biopsies revealed a histiocytic infiltrate in the superficial dermis that was S100 protein-negative by immunoperoxidase (PAP method). One patient showed comma-shaped bodies and desmosomelike junctions on electron microscopy. No Birbeck's granules were present. Benign cephalic histiocytosis is a self-limiting condition that requires no treatment.

  10. Standardized EEG interpretation accurately predicts prognosis after cardiac arrest

    DEFF Research Database (Denmark)

    Westhall, Erik; Rossetti, Andrea O; van Rootselaar, Anne-Fleur;

    2016-01-01

    OBJECTIVE: To identify reliable predictors of outcome in comatose patients after cardiac arrest using a single routine EEG and standardized interpretation according to the terminology proposed by the American Clinical Neurophysiology Society. METHODS: In this cohort study, 4 EEG specialists...... patients. EEGs were recorded in 103 patients at a median 77 hours after cardiac arrest; 37% had a highly malignant EEG and all had a poor outcome (specificity 100%, sensitivity 50%). Any malignant EEG feature had a low specificity to predict poor prognosis (48%) but if 2 malignant EEG features were present...

  11. EEG II. Annexes and regulations. Comment; EEG II. Anlagen und Verordnungen. Kommentar

    Energy Technology Data Exchange (ETDEWEB)

    Frenz, Walter (ed.) [Rheinisch-Westfaelische Technische Hochschule Aachen (Germany). Berg-, Umwelt- und Europarecht

    2016-11-01

    Berlin commentary EEG II: safe through the paraphernalia Like hardly any other law, the Renewable Energies Act (EEG) is subject to constant changes. With the 2014 amendment, the EEG was fundamentally redesigned. This makes the application of the complex rules a challenge even for experts. In addition, the sub-rules contain important statements in the form of numerous annexes and regulations - with the EEG amendment 2014, this has become even more detailed. In it, many calculations are only defined in detail and the legal provisions of the EEG are made more definite and supplemented. The Berlin commentary EEG II accompanies you expertly through this complex matter. Experts explain the widely divergent rules in practice. If necessary for a better understanding, the provisions of the EEG 2014 are also explained. Consistently designed for your practice As a buyer of the work, you also benefit from access to an extensive, regularly updated database. This contains important legal energy regulations of the EU, the federal government and the countries. Even earlier legal positions remain searchable and can be conveniently compared with current versions. So you can see at a glance what has changed. [German] Berliner Kommentar EEG II: sicher durch den Paragrafengeflecht Wie kaum ein anderes Gesetz ist das Erneuerbare-Energien-Gesetz (EEG) staendigen Aenderungen unterworfen. Mit der Novelle 2014 wurde das EEG grundlegend umgestaltet. Dies macht die Anwendung der komplexen Regeln selbst fuer Experten zu einer Herausforderung. Zudem enthaelt auch das untergesetzliche Regelwerk wichtige Aussagen in Form zahlreicher Anlagen und Verordnungen - mit der EEG-Novelle 2014 ist dieses noch ausfuehrlicher geworden. In ihm werden viele Berechnungen erst naeher festgelegt und gesetzliche Bestimmungen des EEG entscheidend konkretisiert und ergaenzt. Der Berliner Kommentar EEG II begleitet Sie fachkundig durch diese komplexe Materie. Experten erlaeutern Ihnen praxisorientiert die

  12. Review of Prostate Anatomy and Embryology and the Etiology of Benign Prostatic Hyperplasia.

    Science.gov (United States)

    Aaron, LaTayia; Franco, Omar E; Hayward, Simon W

    2016-08-01

    Prostate development follows a common pattern between species and depends on the actions of androgens to induce and support ductal branching morphogenesis of buds emerging from the urogenital sinus. The human prostate has a compact zonal anatomy immediately surrounding the urethra and below the urinary bladder. Rodents have a lobular prostate with lobes radiating away from the urethra. The human prostate is the site of benign hyperplasia, prostate cancer, and prostatitis. The rodent prostate has little naturally occurring disease. Rodents can be used to model aspects of human benign hyperplasia, but care should be taken in data interpretation and extrapolation to the human condition.

  13. Pleasant/Unpleasant Filtering for Affective Image Retrieval Based on Cross-Correlation of EEG Features

    Directory of Open Access Journals (Sweden)

    Keranmu Xielifuguli

    2014-01-01

    Full Text Available People often make decisions based on sensitivity rather than rationality. In the field of biological information processing, methods are available for analyzing biological information directly based on electroencephalogram: EEG to determine the pleasant/unpleasant reactions of users. In this study, we propose a sensitivity filtering technique for discriminating preferences (pleasant/unpleasant for images using a sensitivity image filtering system based on EEG. Using a set of images retrieved by similarity retrieval, we perform the sensitivity-based pleasant/unpleasant classification of images based on the affective features extracted from images with the maximum entropy method: MEM. In the present study, the affective features comprised cross-correlation features obtained from EEGs produced when an individual observed an image. However, it is difficult to measure the EEG when a subject visualizes an unknown image. Thus, we propose a solution where a linear regression method based on canonical correlation is used to estimate the cross-correlation features from image features. Experiments were conducted to evaluate the validity of sensitivity filtering compared with image similarity retrieval methods based on image features. We found that sensitivity filtering using color correlograms was suitable for the classification of preferred images, while sensitivity filtering using local binary patterns was suitable for the classification of unpleasant images. Moreover, sensitivity filtering using local binary patterns for unpleasant images had a 90% success rate. Thus, we conclude that the proposed method is efficient for filtering unpleasant images.

  14. Personalized Medicine: Review and Perspectives of Promising Baseline EEG Biomarkers in Major Depressive Disorder and Attention Deficit Hyperactivity Disorder.

    Science.gov (United States)

    Olbrich, Sebastian; van Dinteren, Rik; Arns, Martijn

    2015-01-01

    Personalized medicine in psychiatry is in need of biomarkers that resemble central nervous system function at the level of neuronal activity. Electroencephalography (EEG) during sleep or resting-state conditions and event-related potentials (ERPs) have not only been used to discriminate patients from healthy subjects, but also for the prediction of treatment outcome in various psychiatric diseases, yielding information about tailored therapy approaches for an individual. This review focuses on baseline EEG markers for two psychiatric conditions, namely major depressive disorder and attention deficit hyperactivity disorder. It covers potential biomarkers from EEG sleep research and vigilance regulation, paroxysmal EEG patterns and epileptiform discharges, quantitative EEG features within the EEG main frequency bands, connectivity markers and ERP components that might help to identify favourable treatment outcome. Further, the various markers are discussed in the context of their potential clinical value and as research domain criteria, before giving an outline for future studies that are needed to pave the way to an electrophysiological biomarker-based personalized medicine.

  15. Anatomical substrate and scalp EEG markers are correlated in subjects with cognitive impairment and Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    davide v Moretti

    2011-01-01

    Full Text Available Dementia is a syndromic diagnosis, encompassing various stage of severity and different anatomo-physiological substrates. The hippocampus is one of the first and most affected brain regions affected by both Alzheimer’s disease (AD and mild cognitive impairment (MCI. Morevoer, cronic cerebrovascular disease (CVD is one of the major risk factor for developing dementia. Recent studies have demonstrated different relationship between the anatomical substrate and scalp electroencephalography (EEG markers. Indeed, modifications of EEG rhythmicity is not proportional to the hippocampal atrophy, whereas changes in EEG activity are directly proportional to the load of subcortical CVD.Quantitative EEG have been demonstrated a reliable tool in identifying specific patterns in dementia research (Coburn et al., 2006; John and Prichep, 2006. The computation of the spectral power and the analysis of the functional coupling of brain areas, through linear coherence, are two of the most known processing methods in EEG research. Two specific EEG markers, theta/gamma and alpha3/alpha2 frequency ratio have been reliable associated to the atrophy of amygdalo-hippocampal complex. Moreover, theta/gamma ratio has been related to MCI conversion i

  16. Urodynamic implications of benign prostatic hyperplasia

    DEFF Research Database (Denmark)

    Jensen, K M; Andersen, J T

    1990-01-01

    By the age of 60, about 70% of men have developed benign prostatic hyperplasia (BPH), and 85%-95% of these have symptomatic dysfunction of the lower urinary tract, 10%-20% undergoing prostatectomy. Although transurethral resection of the prostate is generally considered to be a safe and effective...

  17. Laparoscopic Management of Benign Ovarian Masses

    Directory of Open Access Journals (Sweden)

    Rachana Saha

    2013-12-01

    Full Text Available Introduction: Laparoscopic surgery is one of the most common procedures performed for benign ovarian masses. The aim of the study was to analyze all benign ovarian masses treated laparoscopically to assess safety, feasibility and outcome. Methods: A prospective study was carried out at Kathmandu Medical College Teaching Hospital, Sinamangal, Nepal. All the patients undergoing laparoscopic surgery for benign ovarian masses from 1st January 2012 to 31st December 2012 were included in the study. The pre-operative findings, intra-operative findings, operative techniques and post-operative complications were analyzed. Results: Thirty-six patients were taken for the study. Two cases were excluded since intra-operatively they were tubo-ovarian masses. The most common tumor was dermoid cyst (n=13; 38.23% and endometriotic cyst (n=14; 41.17%. Out of 34 cases, five cases of endometriotic cyst (14.70% were converted to laparotomy due to severe adhesions and four cases of endometriotic cyst underwent deroofing surgery. Two cases underwent laparoscopic assisted vaginal hysterectomy with bilateral salphingo-oopherectomy. Successful cystectomies were carried out in 22 cases. None were malignant. Major complications were not noted while minor complications like port-site infection (n=3; 8.82% and subcutaneous emphysema (n=1; 2.9% were present. Conclusions: Laproscopic management of benign ovarian masses is safe and feasible.

  18. Imaging features of benign adrenal cysts

    Energy Technology Data Exchange (ETDEWEB)

    Sanal, Hatice Tuba [Department of Radiology, Gulhane Military Medical Academy, Ankara (Turkey)]. E-mail: tubasanal@yahoo.com; Kocaoglu, Murat [Department of Radiology, Gulhane Military Medical Academy, Ankara (Turkey); Yildirim, Duzgun [Department of Radiology, Gulhane Military Medical Academy, Ankara (Turkey); Bulakbasi, Nail [Department of Radiology, Gulhane Military Medical Academy, Ankara (Turkey); Guvenc, Inanc [Department of Radiology, Gulhane Military Medical Academy, Ankara (Turkey); Tayfun, Cem [Department of Radiology, Gulhane Military Medical Academy, Ankara (Turkey); Ucoz, Taner [Department of Radiology, Gulhane Military Medical Academy, Ankara (Turkey)

    2006-12-15

    Benign adrenal gland cysts (BACs) are rare lesions with a variable histological spectrum and may mimic not only each other but also malignant ones. We aimed to review imaging features of BACs which can be helpful in distinguishing each entity and determining the subsequent appropriate management.

  19. Benign prostatic hyperplasia: symptoms and objective interpretation

    DEFF Research Database (Denmark)

    Andersen, J T

    1991-01-01

    Considerable new knowledge about benign prostatic hyperplasia has been gained over the past two decades, particularly with regard to its natural history, hydrodynamic changes in the lower urinary tract, and the symptomatic and urodynamic results of treatment. A survey of the literature has been u...

  20. Differentiating benign from malignant bone tumors using fluid-fluid level features on magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hong; Cui, Jian Ling; Cui, Sheng Jie; Sun, Ying Cal; Cui, Feng Zhen [Dept. of Radiology, The Third Hospital of Hebei Medical University, Hebei Province Biomechanical Key Laborary of Orthopedics, Shijiazhuang, Hebei (China)

    2014-12-15

    To analyze different fluid-fluid level features between benign and malignant bone tumors on magnetic resonance imaging (MRI). This study was approved by the hospital ethics committee. We retrospectively analyzed 47 patients diagnosed with benign (n = 29) or malignant (n = 18) bone tumors demonstrated by biopsy/surgical resection and who showed the intratumoral fluid-fluid level on pre-surgical MRI. The maximum length of the largest fluid-fluid level and the ratio of the maximum length of the largest fluid-fluid level to the maximum length of a bone tumor in the sagittal plane were investigated for use in distinguishing benign from malignant tumors using the Mann-Whitney U-test and a receiver operating characteristic (ROC) analysis. Fluid-fluid level was categorized by quantity (multiple vs. single fluid-fluid level) and by T1-weighted image signal pattern (high/low, low/high, and undifferentiated), and the findings were compared between the benign and malignant groups using the chi2 test. The ratio of the maximum length of the largest fluid-fluid level to the maximum length of bone tumors in the sagittal plane that allowed statistically significant differentiation between benign and malignant bone tumors had an area under the ROC curve of 0.758 (95% confidence interval, 0.616-0.899). A cutoff value of 41.5% (higher value suggests a benign tumor) had sensitivity of 73% and specificity of 83%. The ratio of the maximum length of the largest fluid-fluid level to the maximum length of a bone tumor in the sagittal plane may be useful to differentiate benign from malignant bone tumors.

  1. Mahalanobis Distance-Based Classifiers are Able to Recognize EEG Patterns by Using Few EEG Electrodes

    Science.gov (United States)

    2007-11-02

    Mouriño 3 , Angela Cattini 4 , Serenella Salinari 4 , Maria Grazia Marciani 2,5 and Febo Cincotti 5 1 Dip. Fisiologia umana e Farmacologia...Performing Organization Name(s) and Address(es) Dip. Fisiologia umana e Farmacologia, Università "La Sapienza", Rome, ITALY Performing Organization

  2. Dynamic EEG-informed fMRI modeling of the pain matrix using 20-ms root mean square segments.

    Science.gov (United States)

    Brinkmeyer, Juergen; Mobascher, Arian; Warbrick, Tracy; Musso, Francesco; Wittsack, Hans-Jörg; Saleh, Andreas; Schnitzler, Alfons; Winterer, Georg

    2010-11-01

    Previous studies on the spatio-temporal dynamics of cortical pain processing using electroencephalography (EEG), magnetoencephalography (MEG), or intracranial recordings point towards a high degree of parallelism, e.g. parallel instead of sequential activation of primary and secondary somatosensory areas or simultaneous activation of somatosensory areas and the mid-cingulate cortex. However, because of the inverse problem, EEG and MEG provide only limited spatial resolution and certainty about the generators of cortical pain-induced electromagnetic activity, especially when multiple sources are simultaneously active. On the other hand, intracranial recordings are invasive and do not provide whole-brain coverage. In this study, we thought to investigate the spatio-temporal dynamics of cortical pain processing in 10 healthy subjects using simultaneous EEG/functional magnetic resonance imaging (fMRI). Voltages of 20 ms segments of the EEG root mean square (a global, largely reference-free measure of event-related EEG activity) in a time window 0-400 ms poststimulus were used to model trial-to-trial fluctuations in the fMRI blood oxygen level dependent (BOLD) signal. EEG-derived regressors explained additional variance in the BOLD signal from 140 ms poststimulus onward. According to this analysis, the contralateral parietal operculum was the first cortical area to become activated upon painful laser stimulation. The activation pattern in BOLD analyses informed by subsequent EEG-time windows suggests largely parallel signal processing in the bilateral operculo-insular and mid-cingulate cortices. In that regard, our data are in line with previous reports. However, the approach presented here is noninvasive and bypasses the inverse problem using only temporal information from the EEG.

  3. EEG Findings May Serve as a Potential Biomarker for Anti-NMDA Receptor Encephalitis.

    Science.gov (United States)

    Foff, Erin Pennock; Taplinger, David; Suski, Joanna; Lopes, M Beatriz S; Quigg, Mark

    2017-01-01

    Objective To determine if an electroencephalographic (EEG) characteristic, beta:delta power ratio (BDPR), is significantly higher for N-methyl-d-aspartate receptor encephalitis (NMDARE) patients than for non-NMDARE patients on presenting EEG. Identification of an additional EEG biomarker with significant specificity for NMDARE (in the absence of frank delta brush) could potentially allow for early identification of at-risk patients. Methods Single center retrospective comparison of NMDARE and non-NMDARE consecutive cases of encephalitis, collated over a 6-year period (from 2008 to 2014). Results None of the 10 NMDARE patients displayed the extreme delta brush pattern on EEG previously described, but the ratio of BDPR was significantly higher for NMDARE patients (P < .005). There was no significant relationship between BDPR and the time of recording from symptom onset. Additional analysis of clinical characteristics also indicated that the patients with NMDARE (median age 19.5 years) were younger than the 5 patients with non-NMDARE (median age 36 years). Encephalopathy, seizure, and psychiatric complaints were the most common diagnoses at time of first health care presentation and did not favor a single etiology, though the latter was present only in the NMDARE population (50% at T0). Prodromal illness featuring headache was more common in the non-NMDARE population. Outcomes, as measured by the Modified Rankin Scale, were globally better in the NMDARE group. Conclusions Patients with NMDARE had a significantly higher BDPR on EEG when compared with non-NMDARE patients even in the absence of extreme delta brush. This suggests that early EEG characteristics may be helpful in distinguishing NMDARE from non-NMDARE.

  4. Natural history of benign prostate hyperplasia

    Institute of Scientific and Technical Information of China (English)

    WU Shi-liang; LI Ning-chen; XIAO Yun-xiang; JIN Jie; QIU Shao-peng; YE Zhang-qun; KONG Chui-ze; SUN Guang; NA Yan-qun

    2006-01-01

    Background Benign prostate hyperplasia is one of the most common diseases affecting the health of the aging males. Watchful waiting is an acceptable management strategy for benign prostate hyperplasia in which the patient is monitored by the physician but receives no active intervention. The epidemiological data on this are lacking in China. Our study was designed to evaluate the changes of signs and symptoms of patients with benign prostate hyperplasia during management by watchful waiting in China.Methods One hundred and forty-five patients with benign prostate hyperplasia aged > 50 years were enrolled in management by watchful waiting. All the patients were visited every 6 months and were given an International Prostate Symptom Score and Quality of Life questionnaire to complete. They also had uroflowmetry and were assessed using ultrasonography to get the volume of prostate, transition zone and amount of residual urine. The Student's t test, the Chi-square test, and variance analysis were used in the statistical analysis.Results All patients were visited after 6 months, the mean volume of transitional zone was found to haveincreased by 1.6 ml (P<0.01), International Prostate Symptom Score was increased by 0.8 (P<0.01) and Quality of Life was increased by 0.2 (P<0.01), and there was no statistical change in other data. Among these patients,17.9% (26/145) visited again after 12 months when the data failed to show a statistically significant difference among the three groups (0, 6, and 12 months).Conclusions After one year's follow-up, the progression of benign prostate hyperplasia was slow and the clinical data did not undergo much change.

  5. Comparison of ictal and interictal EEG signals using fractal features.

    Science.gov (United States)

    Wang, Yu; Zhou, Weidong; Yuan, Qi; Li, Xueli; Meng, Qingfang; Zhao, Xiuhe; Wang, Jiwen

    2013-12-01

    The feature analysis of epileptic EEG is very significant in diagnosis of epilepsy. This paper introduces two nonlinear features derived from fractal geometry for epileptic EEG analysis. The features of blanket dimension and fractal intercept are extracted to characterize behavior of EEG activities, and then their discriminatory power for ictal and interictal EEGs are compared by means of statistical methods. It is found that there is significant difference of the blanket dimension and fractal intercept between interictal and ictal EEGs, and the difference of the fractal intercept feature between interictal and ictal EEGs is more noticeable than the blanket dimension feature. Furthermore, these two fractal features at multi-scales are combined with support vector machine (SVM) to achieve accuracies of 97.58% for ictal and interictal EEG classification and 97.13% for normal, ictal and interictal EEG classification.

  6. Removal of ocular artifacts from the REM sleep EEG

    NARCIS (Netherlands)

    D. Waterman; J.C. Woestenburg; M. Elton; W. Hofman; A. Kok

    1992-01-01

    The present report concerns the first study in which electrooculographic (EOG) contamination of electroencephalographic (EEG) recordings in rapid eye movement (REM) sleep is systematically investigated. Contamination of REM sleep EEG recordings in six subjects was evaluated in the frequency domain.

  7. A dry electrode for EEG recording.

    Science.gov (United States)

    Taheri, B A; Knight, R T; Smith, R L

    1994-05-01

    This paper describes the design, fabrication and testing of a prototype dry surface electrode for EEG signal recording. The new dry electrode has the advantages of no need for skin preparation or conductive paste, potential for reduced sensitivity to motion artifacts and an enhanced signal-to-noise ratio. The electrode's sensing element is a 3 mm stainless steel disk which has a 2000 A (200 nm) thick nitride coating deposited onto one side. The back side of the disk is attached to an impedance converting amplifier. The prototype electrode was mounted on a copper plate attached to the scalp by a Velcro strap. The performance of this prototype dry electrode was compared to commercially available wet electrodes in 3 areas of electroencephalogram (EEG) recording: (1) spontaneous EEG, (2) sensory evoked potentials, and (3) cognitive evoked potentials. In addition to the raw EEG, the power spectra of the signals from both types of electrodes were also recorded. The results suggest that the dry electrode performs comparably to conventional electrodes for all types of EEG signal analysis. This new electrode may be useful for the production of high resolution surface maps of brain activity where a large number of electrodes or prolonged recording times are required.

  8. Endo-biliary stents for benign disease: not always benign after all!

    Directory of Open Access Journals (Sweden)

    Jo-Etienne Abela

    2011-11-01

    Full Text Available This case report describes the presentation, management and treatment of a patient who suffered small bowel perforation due to the migration of his biliary stent which had been inserted for benign disease.

  9. Role of Duplex Power Doppler Ultrasound in Differentiation between Malignant and Benign Thyroid Nodules

    Energy Technology Data Exchange (ETDEWEB)

    Algin, Oktay [Ataturk Training and Research Hospital Bilkent, Ankara (Turkmenistan); Algin, Efnan [Gazi University Medical Faculty, Ankara (Turkmenistan); Gokalp, Gokhan; Ocakog, Gokhan; Erdog an, Cuneyt; Saraydaroglu, Ozlem; Ercan Tuncel, Prof [Uludag University Medical Faculty, Bursa (Turkmenistan)

    2010-12-15

    To evaluate the usage of duplex power Doppler ultrasound (PDUS) for the differentiation of benign and malignant thyroid nodules. We prospectively examined 77 thyroid nodules in 60 patients undergoing ultrasound-guided fine needle aspiration biopsy (FNAB). Each nodule was described according to size, inner structure, borders, parenchymal echogenicity, peripheral halo formation, and the presence of calcification (Bmode ultrasound findings). Vascularity as determined by PDUS imaging was defined as non-vascular, peripheral, central, or of mixed type. For each nodule, the pulsatility index (PI) and resistive index (RI) values were obtained. Results of FNAB and surgical pathological examination (if available) were used as a proof of final diagnosis to categorize all nodules as benign or malignant. A receiver operating characteristic (ROC) curve analysis was performed to establish cut-off, sensitivity, and specificity values associated with RI-PI values. A significant relationship was observed between malignancy and irregular margins, microcalcifications, and hypoechogenicity on ultrasound examination (p < 0.05). The pattern of vascularity as determined by PDUS analysis was not a statistically significant criterion to suggest benign or malignant disease in this study (p > 0.05). The central, peripheral, and mean RI-PI values were higher in malignant nodules when compared to the other cytologies (p < 0.05). Vascularity is not a useful parameter for distinguishing malignant from benign thyroid nodules. However, RI and PI values are useful in distinguishing malignant from benign thyroid nodules

  10. The Important Morphological Parameters Used to Differentiate Benign/Malignant Phyllodes Tumors of the Breast

    Directory of Open Access Journals (Sweden)

    Ülkü KÜÇÜK

    2012-09-01

    Full Text Available Objective: Phyllodes tumor is a rare fibroepithelial neoplasia of the breast. Tumors are classified according to the histological criteria as benign, borderline, malignant groups. Criteria used to discriminate benign/malignant cases are stromal cytological atypia, stromal hypercellularity, mitotic rate, stromal overgrowth, and tumor margins. We designed this study retrospectively to see the validity of these criteria for our case group and investigate whether we could add any new criteria.Material and Method: We included 22 cases diagnosed as phyllodes tumor from our archives. Pathology records were used for age, tumor site, macroscopic size. The Hematoxylin-Eosin stained slides were reviewed according to the defined criteria. Additionally leaf like growth pattern, stromal hyalinization, calcification, stromal giant cells, stromal neutrophil leukocyte, and mononuclear lymphocytic infiltrate were recorded qualitatively (present/absent and numerically (mild, moderate, severe. We examined the differences between benign and malignant groups with the Mann-Whitney U and chi-square tests.Results: The previously defined criteria were statistically significant but stromal giant cells, stromal hyalinization, calcification, stromal neutrophil and mononuclear lymphocytic infiltrate intensity were not statistically significant in determining the benign-borderlinemalignant cases.Conclusion: Stromal hypercellularity, moderate/severe stromal cytological atypia, increased mitotic rate, stromal overgrowth and infiltrative tumor margins were observed in malignant phyllodes tumors. Malignant cases were also older and tumor size was bigger than benign ones.

  11. Benign multicystic mesothelioma: a case report of three sisters

    Directory of Open Access Journals (Sweden)

    Thomas Rutherford

    2009-12-01

    Full Text Available Benign multicystic mesothelioma (BMCM is a rare tumor of the abdomen-peritoneum of unknown etiology. This benign tumor was initially described by Plaut in 1928 when he observed loose cysts in the pelvis during a surgery for a uterine leiomyoma.2 The mesothelial origin was later confirmed by electron micro-scopy by Mennemeyer and Smith in 1979.3 To date, there are approximately 140 cases of BMCM reported in the literature.4 This disease primarily occurs in pre-menopausal women and is associated with a history of pelvic inflammatory disease, prior abdominal surgery, and endometriosis.4,5 The pathogenesis of this disease remains controversial, with possible etiologies including a neoplastic versus a reactive process.5 In the literature, a few case reports discuss a possible genetic or familial association with BMCM.6 Specifically, one report describes a man with familial Mediterranean fever who developed BMCM. Although familial Mediter-ranean fever is associated with malignant mesothelioma, he had only BMCM, and did not suffer from malignant mesothelioma.6 A genetic evaluation and chromosomal analysis were not able to identify a specific genetic cause of the family’s pattern of disease. This case report describes two female siblings diagnosed with BMCM. In addition, a third sister also had findings consistent with BMCM, however, the discrete histological diagnosis was never confirmed.

  12. Sertoliform cystadenoma: a rare benign tumour of the rete testis

    Directory of Open Access Journals (Sweden)

    Bremmer Felix

    2013-02-01

    Full Text Available Abstract Sertoliform cystadenoma of the rete testis represents an uncommon benign tumour. They appear in patients from 26 to 62 years of age. We describe a case of a 66-year-old man with a tumour in the area of the epididymal head. The tumour markers were not increased. Under the assumption of a malignant testicular tumour an inguinal orchiectomy was performed. The cut surface of this tumour was of grey/white color and showed small cysts. The tumour consisted of two compartments. The epithelial like tumour cells showed a sertoliform growth pattern and cystic dilatations. In between the tumour cells repeatedly actin expressing sclerotic areas could be recognized as the second tumour component. Proliferative activity was not increased. Immunohistochemically the tumour cells were positiv for inhibin, S-100, and CD 99. Alpha feto protein (AFP, human chorionic gonadotropin (ß-HCG and placental alkaline phosphatase (PLAP as well as synaptophysin, epithelial membrane antigene (EMA, and BCL-2 were not expressed. As far as we know this is the sixth reported case of this tumour. Because of the benign nature of this tumour the correct diagnosis is important for the intra- and postoperative management. Here we present a case of this rare tumour and discuss potential differential diagnosis. Virtual Slides The virtual slide(s for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1956026143857335

  13. Nonlinear Analysis of Clinical Epileptic EEG by Approximate Entropy

    Institute of Scientific and Technical Information of China (English)

    LIU Yan-su; XIA Yang; XU Hong-ru; ZHOU Dong; YAO De-zhong

    2005-01-01

    By the means of computing approximate entropy (ApEn) of video-EEG from some clinical epileptic, ApEn of EEG with epileptiform discharges is found significantly different from that of EEG without epileptiform discharges, (p=0. 002). Meanwhile, dynamic ApEn shows consistent change of EEG signal withdischarges of epileptic waves inside. These results suggest that ApEn may be a useful tool for automatic recognition and detection of epileptic activity and for understanding epileptogenic mechanism.

  14. Dynamics of EEG Entropy: beyond signal plus noise

    CERN Document Server

    Ignaccolo, M; Jernajczyk, W; Grigolini, P; West, B J

    2009-01-01

    EEG time series are analyzed using the diffusion entropy method. The resulting EEG entropy manifests short-time scaling, asymptotic saturation and an attenuated alpha-rhythm modulation. These properties are faithfully modeled by a phenomenological Langevin equation interpreted within a neural network context. Detrended fluctuation analysis of the EEG data is compared with diffusion entropy analysis and is found to suppress certain important properties of the EEG time series.

  15. Emotional responses as independent components in EEG

    DEFF Research Database (Denmark)

    Jensen, Camilla Birgitte Falk; Petersen, Michael Kai; Larsen, Jakob Eg

    2014-01-01

    Combine wireless neuroheadsets with smartphones that enable mobile brain imaging can potentially allow us to design cognitive interfaces which adapt to our affective responses. Neuroimaging experiments using electroencephalography (EEG) initially identified two components elicited by pleasant...... susceptible to noise if captured in a mobile context. Hypothesizing that retrieval of emotional responses in mobile usage scenarios could be enhanced through spatial filtering, we compare a standard EEG electrode based analysis against an approach based on independent component analysis (ICA). By clustering...... scalp maps and time series responses we identify neural signatures that are differentially modulated when passively viewing neutral, pleasant and unpleasant images. While early responses can be detected from the raw EEG signal we identify multiple early and late ICA components that are modulated...

  16. Implanted electrodes for multi-month EEG.

    Science.gov (United States)

    Jochum, Thomas; Engdahl, Susannah; Kolls, Brad J; Wolf, Patrick

    2014-01-01

    An implanted electroencephalogram (EEG) recorder would help diagnose infrequent seizure-like events. A proof-of-concept study quantified the electrical characteristics of the electrodes planned for the proposed recorder. The electrodes were implanted in an ovine model for eight weeks. Electrode impedance was less than 800 Ohms throughout the study. A frequency-domain determination of sedation performed similarly for surface versus implanted electrodes throughout the study. The time-domain correlation between an implanted electrode and a surface electrode was almost as high as between two surface electrodes (0.86 versus 0.92). EEG-certified clinicians judged that the implanted electrode quality was adequate to excellent and that the implanted electrodes provided the same clinical information as surface electrodes except for a noticeable amplitude difference. No significant issues were found that would stop development of the EEG recorder.

  17. Insights from intermittent binocular rivalry and EEG

    Directory of Open Access Journals (Sweden)

    Michael A Pitts

    2011-09-01

    Full Text Available Novel stimulation and analytical approaches employed in EEG studies of ambiguous figures have recently been applied to binocular rivalry. The combination of intermittent stimulus presentation and EEG source imaging has begun to shed new light on the neural underpinnings of binocular rivalry. Here, we review the basics of the intermittent paradigm and highlight methodological issues important for interpreting previous results and designing future experiments. We then outline current analytical approaches, including EEG microstates, event-related potentials, and statistically-based source estimation, and propose a spatio-temporal model that integrates findings from several studies. Finally, we discuss the advantages and limitations of using binocular rivalry as a tool to investigate the neural basis of perceptual awareness.

  18. A Study on Melody Tempo with EEG

    Institute of Scientific and Technical Information of China (English)

    Yuan Yuan; Yong-Xiu Lai; Dan Wu; De-Zhong Yao

    2009-01-01

    In this paper,tempo perception is investi-gated by recording spontaneous electroencephalograph (EEG).Ten normal male non-musician college students are selected according to questionnaire results after listening absorbedly to four different tempos of an excerpt from a Mozart sonata.EEGs data are recorded when the subjects are listening to the music.The EEG spectral power (SP) is analyzed for alpha band.The varying trend of power spectrum during exposure to music excerpts of different tempos is studied and shows the consistence with the previous tempo-specific hypo-thesis:a tempo-transformed performance will sound less natural than an original performance does.The results presented in this paper suggest that tempo is an important factor that could influence the alpha rhythm.

  19. Modular, bluetooth enabled, wireless electroencephalograph (EEG) platform.

    Science.gov (United States)

    Lovelace, Joseph A; Witt, Tyler S; Beyette, Fred R

    2013-01-01

    A design for a modular, compact, and accurate wireless electroencephalograph (EEG) system is proposed. EEG is the only non-invasive measure for neuronal function of the brain. Using a number of digital signal processing (DSP) techniques, this neuronal function can be acquired and processed into meaningful representations of brain activity. The system described here utilizes Bluetooth to wirelessly transmit the digitized brain signal for an end application use. In this way, the system is portable, and modular in terms of the device to which it can interface. Brain Computer Interface (BCI) has become a popular extension of EEG systems in modern research. This design serves as a platform for applications using BCI capability.

  20. Low power wireless EEG headset for BCI applications

    NARCIS (Netherlands)

    Patki, S.; Grundlehner, B.; Nakada, T.; Penders, J.

    2011-01-01

    Miniaturized, low power and low noise circuits and systems are instrumental in bringing EEG monitoring to the home environment. In this paper, we present a miniaturized, low noise and low-power EEG wireless platform integrated into a wearable headset. The wireless EEG headset achieves remote and wea

  1. 21 CFR 882.1855 - Electroencephalogram (EEG) telemetry system.

    Science.gov (United States)

    2010-04-01

    ... signals by means of radio or telephone transmission systems. (b) Classification. Class II (performance... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Electroencephalogram (EEG) telemetry system. 882... Electroencephalogram (EEG) telemetry system. (a) Identification. An electroencephalogram (EEG) telemetry...

  2. Improving the Specificity of EEG for Diagnosing Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    François-B. Vialatte

    2011-01-01

    Full Text Available Objective. EEG has great potential as a cost-effective screening tool for Alzheimer's disease (AD. However, the specificity of EEG is not yet sufficient to be used in clinical practice. In an earlier study, we presented preliminary results suggesting improved specificity of EEG to early stages of Alzheimer's disease. The key to this improvement is a new method for extracting sparse oscillatory events from EEG signals in the time-frequency domain. Here we provide a more detailed analysis, demonstrating improved EEG specificity for clinical screening of MCI (mild cognitive impairment patients. Methods. EEG data was recorded of MCI patients and age-matched control subjects, in rest condition with eyes closed. EEG frequency bands of interest were θ (3.5–7.5 Hz, α1 (7.5–9.5 Hz, α2 (9.5–12.5 Hz, and β (12.5–25 Hz. The EEG signals were transformed in the time-frequency domain using complex Morlet wavelets; the resulting time-frequency maps are represented by sparse bump models. Results. Enhanced EEG power in the θ range is more easily detected through sparse bump modeling; this phenomenon explains the improved EEG specificity obtained in our previous studies. Conclusions. Sparse bump modeling yields informative features in EEG signal. These features increase the specificity of EEG for diagnosing AD.

  3. Analysis of routine EEG usage in a general adult ICU.

    LENUS (Irish Health Repository)

    McHugh, J C

    2009-09-01

    Non-convulsive seizures and status epilepticus are common in brain-injured patients in intensive care units. Continuous electroencephalography (cEEG) monitoring is the most sensitive means of their detection. In centres where cEEG is unavailable, routine EEG is often utilized for diagnosis although its sensitivity is lower.

  4. EEG. Renewables Act. Comment. 3. new rev. and enl. ed.; EEG. Erneuerbare-Energien-Gesetz. Kommentar

    Energy Technology Data Exchange (ETDEWEB)

    Frenz, Walter [Rheinisch-Westfaelische Technische Hochschule (RWTH), Aachen (Germany). Lehr- und Forschungsgebiet Berg-, Umwelt- und Europarecht; Mueggenborg, Hans-Juergen (eds.) [Kassel Univ. (Germany)

    2013-05-01

    Like hardly any other law, the Renewable Energy Sources Law (EEG) is a subject to continuing modifications. This makes the application of the already complicated regulations even for experts to a special challenge. With the proven Berliner comment EEG, now a reliable companion through the bureaucratic jungle is available. All regulations of the EEG are commented precisely and easily to understand by profound experts. An extensive selection of terminology enables a rapid orientation within this book. In addition to the excursions to renewable energy technologies, this book also describes the structural aspects in the establishment of a photovoltaic system.

  5. Intracranial EEG potentials estimated from MEG sources: A new approach to correlate MEG and iEEG data in epilepsy.

    Science.gov (United States)

    Grova, Christophe; Aiguabella, Maria; Zelmann, Rina; Lina, Jean-Marc; Hall, Jeffery A; Kobayashi, Eliane

    2016-05-01

    Detection of epileptic spikes in MagnetoEncephaloGraphy (MEG) requires synchronized neuronal activity over a minimum of 4cm2. We previously validated the Maximum Entropy on the Mean (MEM) as a source localization able to recover the spatial extent of the epileptic spike generators. The purpose of this study was to evaluate quantitatively, using intracranial EEG (iEEG), the spatial extent recovered from MEG sources by estimating iEEG potentials generated by these MEG sources. We evaluated five patients with focal epilepsy who had a pre-operative MEG acquisition and iEEG with MRI-compatible electrodes. Individual MEG epileptic spikes were localized along the cortical surface segmented from a pre-operative MRI, which was co-registered with the MRI obtained with iEEG electrodes in place for identification of iEEG contacts. An iEEG forward model estimated the influence of every dipolar source of the cortical surface on each iEEG contact. This iEEG forward model was applied to MEG sources to estimate iEEG potentials that would have been generated by these sources. MEG-estimated iEEG potentials were compared with measured iEEG potentials using four source localization methods: two variants of MEM and two standard methods equivalent to minimum norm and LORETA estimates. Our results demonstrated an excellent MEG/iEEG correspondence in the presumed focus for four out of five patients. In one patient, the deep generator identified in iEEG could not be localized in MEG. MEG-estimated iEEG potentials is a promising method to evaluate which MEG sources could be retrieved and validated with iEEG data, providing accurate results especially when applied to MEM localizations. Hum Brain Mapp 37:1661-1683, 2016. © 2016 Wiley Periodicals, Inc.

  6. Benign Multicystic Mesothelioma in the Left Round Ligament: Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Bae, So Young; Yi, Boem Ha; Lee, Hae Kyung; Park, Seong Jin; Cho, Gyu Seok; Kwak, Jeong Ja [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2010-02-15

    Benign multicystic mesothelioma is a rare mesothelial lesion that forms multicystic masses in the upper abdomen, pelvis, and retroperitoneum. Most cases have a benign course. We present the ultrasound and MR findings of benign multicystic mesothelioma in the left round ligament, which caused a left inguinal hernia in a 46-year-old woman.

  7. BENIGN PAROTID TUMORS : AN EXPERIENCE IN A GENERAL SURGICAL UNIT

    Directory of Open Access Journals (Sweden)

    Vijaya

    2015-04-01

    Full Text Available Parotid tumors are mostly benign, but their evaluation and treatment require a thorough knowledge of the relevant anatomy and pathology. Surgical treatment of benign tumors is aimed at complete removal of the mass with facial nerve preservation. The aim of this study was to evaluate the post - operative complications of superficial parotidectomy in benign parotid tumors.

  8. Topographic quantitative EEG amplitude in recovered alcoholics.

    Science.gov (United States)

    Pollock, V E; Schneider, L S; Zemansky, M F; Gleason, R P; Pawluczyk, S

    1992-05-01

    Topographic measures of electroencephalographic (EEG) amplitude were used to compare recovered alcoholics (n = 14) with sex- and age-matched control subjects. Delta, alpha, and beta activity did not distinguish the groups, but regional differences in theta distribution did. Recovered alcoholics showed more uniform distributions of theta amplitudes in bilateral anterior and posterior regions compared with controls. Because a minimum of 5 years had elapsed since the recovered alcoholic subjects fulfilled DSM-III-R criteria for alcohol abuse or dependence, it is unlikely these EEG theta differences reflect the effects of withdrawal.

  9. Fractal Dimension in Epileptic EEG Signal Analysis

    Science.gov (United States)

    Uthayakumar, R.

    Fractal Analysis is the well developed theory in the data analysis of non-linear time series. Especially Fractal Dimension is a powerful mathematical tool for modeling many physical and biological time signals with high complexity and irregularity. Fractal dimension is a suitable tool for analyzing the nonlinear behaviour and state of the many chaotic systems. Particularly in analysis of chaotic time series such as electroencephalograms (EEG), this feature has been used to identify and distinguish specific states of physiological function.Epilepsy is the main fatal neurological disorder in our brain, which is analyzed by the biomedical signal called Electroencephalogram (EEG). The detection of Epileptic seizures in the EEG Signals is an important tool in the diagnosis of epilepsy. So we made an attempt to analyze the EEG in depth for knowing the mystery of human consciousness. EEG has more fluctuations recorded from the human brain due to the spontaneous electrical activity. Hence EEG Signals are represented as Fractal Time Series.The algorithms of fractal dimension methods have weak ability to the estimation of complexity in the irregular graphs. Divider method is widely used to obtain the fractal dimension of curves embedded into a 2-dimensional space. The major problem is choosing initial and final step length of dividers. We propose a new algorithm based on the size measure relationship (SMR) method, quantifying the dimensional behaviour of irregular rectifiable graphs with minimum time complexity. The evidence for the suitability (equality with the nature of dimension) of the algorithm is illustrated graphically.We would like to demonstrate the criterion for the selection of dividers (minimum and maximum value) in the calculation of fractal dimension of the irregular curves with minimum time complexity. For that we design a new method of computing fractal dimension (FD) of biomedical waveforms. Compared to Higuchi's algorithm, advantages of this method include

  10. Development of the EEG apportionment and the EEG differential costs through 2020; Die Entwicklung der EEG-Umlage und der EEG-Differenzkosten bis 2020

    Energy Technology Data Exchange (ETDEWEB)

    Kroll, Annette [Electrabel - GDF SUEZ S.A., Brussels (Belgium); Langrock, Thomas [GDF SUEZ Energie Deutschland AG, Berlin (Germany)

    2011-12-15

    Denial on the one hand and worst case scenarios on the other hand make it difficult for the observer to achieve a rational assessment of current energy policy, especially when it comes to the promotion of renewable energy sources and the German Renewables Act (EEG). This contribution attempts to help: It focuses on the direct cost of the EEG funding system. The scenarios are based on the National Renewable Energy Action Plan and the newly decided package of actions to help along the intended energy turnaround.

  11. WEBspike: A New Proposition of Deterministic Finite Automata and Parallel Algorithm Based Web Application for EEG Spike Recognition

    Directory of Open Access Journals (Sweden)

    Anup Kumar Keshri

    2013-10-01

    Full Text Available The brain signal or Electroencephalogram (EEG has been proved as one of the most important bio-signal that deals with a number of problems and disorders related to the human being. Epilepsy is one of the most commonly known disorders found in humans. The application of EEG in epilepsy related research and treatment is now a very common practice. Variety of smart tools and algorithms exist to assist the experts in taking decision related to the treatment to be provided to an epileptic patient. However, web based applications or tools are still needed that can assist those doctors and experts, who are not having such existing smart tools for EEG analysis with them. In the current work, a web based system named WEBspike has been proposed that breaks the geographical boundary in assisting doctors in taking proper and fast decision regarding the treatment of epileptic patient. The proposed system receives the EEG data from various users through internet and processes it for Epileptic Spike (ES patterns present in it. It sends back a report to the user regarding the appearance of ES pattern present in the submitted EEG data. The average spike recognition rate obtained by the system with the test files, was 99.09% on an average.

  12. Benign paroxysmal positional vertigo following septorhinoplasty.

    Science.gov (United States)

    Koc, Eltaf Ayca Ozbal; Koc, Bulent; Eryaman, Esra; Ozluoglu, Levent N

    2013-01-01

    We present 2 cases of benign paroxysmal positional vertigo (BPPV) following septorhinoplasty. Benign paroxysmal positional vertigo following septorhinoplasty is an unusual entity. Two young women who had difficulty in breathing and nasal deformity underwent septorhinoplasty. On the second and the third postoperative days, the patients experienced vertigo that was induced by position changes. Both patients had neither preexisting ear disease nor vertigo before the surgery. All the examinations were normal. With Dix-Hallpike maneuver, which is the criterion-standard test, the characteristic nystagmus was observed. Right posterior canal BPPV was diagnosed, and they were both treated with Epley canalith repositioning maneuver. Publications related to postsurgical vertigo are available in literature, but it is still an underdiagnosed disorder. We would like to mention about this rare entity and inform the surgeons that they must keep in mind that a patient who is complaining about vertigo or dizziness after the surgery should be observed and investigated for BPPV.

  13. Benign solitary solid cold thyroid nodules

    DEFF Research Database (Denmark)

    Døssing, Helle; Bennedbaek, Finn Noe; Karstrup, Steen;

    2002-01-01

    PURPOSE: To evaluate the effects of ultrasonography (US)-guided interstitial laser photocoagulation (ILP) on the volume of benign solitary solid cold thyroid nodules and any nodule-related symptoms. MATERIALS AND METHODS: ILP was performed in 16 patients with normal thyroid function and a solid...... to evaluate the size of the untreated thyroid nodule. RESULTS: In the 16 patients treated with ILP, the mean thyroid nodule volume decreased from 10 to 5.4 mL (P .... Pressure symptoms were significantly reduced (P =.0002) after 6 months. The treatment was well-tolerated in all patients. No significant change in thyroid nodule volume was seen in the control group. CONCLUSION: US-guided ILP could become a useful nonsurgical alternative in the treatment of the benign...

  14. Characteristics of benign lymphoadenosis of oral mucosa

    Institute of Scientific and Technical Information of China (English)

    Shu-Xia Li; Shi-Feng Yu; Kai-Hua Sun

    2005-01-01

    AIM: To investigate the pathological characteristics and carcinogenesis mechanism of benign lymphoadenosis of oral mucosa (BLOM).METHODS: The expressions of Ki-67, CD34 and apoptosis were evaluated by immunohistochemical SP staining in 64 paraffin-embedded tissue samples. Of them, 9 were from BLOM with dysplasia, 15 from BLOM without dysplasia,15 from oral squamous cell carcinoma (OSCC), 15 from oral precancerosis, and 10 from normal tissues. Cell proliferation, apoptosis and angiogenesis of tissue samples were also analyzed.RESULTS: The expression of Ki-67 in BLOM with dysplasia,oral precancerosis and OSCC was significantly higher than in BLOM without dysplasia and normal mucosa. The microvascular density (MVD) in BLOM with and without dysplasia, oral precancerosis, and OSCC was significantly higher than in normal mucosa. Apoptosis in BLOM and oral precancerosis was significantly higher than in OSCC and normal mucosa.CONCLUSION: Benign lymphoadenosis of oral mucosa has potentialities of cancerization.

  15. Endoscopic therapy of benign biliary strictures

    Institute of Scientific and Technical Information of China (English)

    Joel R Judah; Peter V Draganov

    2007-01-01

    Benign biliary strictures are being increasingly treated with endoscopic techniques. The benign nature of the stricture should be first confirmed in order to ensure appropriate therapy. Surgery has been the traditional treatment, but there is increasing desire for minimally invasive endoscopic therapy. At present, endoscopy has become the first line approach for the therapy of postliver transplant anastomotic strictures and distal (Bismuth Ⅰ and Ⅱ) post-operative strictures. Strictures related to chronic pancreatitis have proven more difficult to treat,and endoscopic therapy is reserved for patients who are not surgical candidates. The preferred endoscopic approach is aggressive treatment with gradual dilation of the stricture and insertion of multiple plastic stents. The use of uncovered self expandable metal stents should be discouraged due to poor long-term results. Treatment with covered metal stents or bioabsorbable stents warrants further evaluation. This area of therapeutic endoscopy provides an ongoing opportunity for fresh research and innovation.

  16. Wicket spikes: clinical correlates of a previously undescribed EEG pattern.

    Science.gov (United States)

    Reiher, J; Lebel, M

    1977-02-01

    From an analysis of the electroencephalograms of 4,458 patients who underwent recording during both wakefulness ans sleep, through the years 1969 to 1975, wicket spikes-- recorded in 39 patients-- may be described as follows: They were found during both wakefulness ans sleep, almost exclusively in adults. Their cardinal feature is a changing mode of occurrence through any single recording: from intermittent trains of more or less sustained, arciform, discharges resembling mu rhythm, to sporadic, urinary, single spikes. When occurring singly, wicket spikes can be mistaken for anterior or middle temporal spikes, since they predominate in eith er area, and since they share with them other characteristics such as amplitude (60 to 210 microvolts), polarity (surface negative) duration, and configuration. Wicket spikes should not be considered interictal abnormalities; they do nor correlate with epilepsy or with any particular symptom complex.

  17. Percutaneous treatment of benign bile duct strictures

    Energy Technology Data Exchange (ETDEWEB)

    Koecher, Martin [Department of Radiology, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic)]. E-mail: martin.kocher@seznam.cz; Cerna, Marie [Department of Radiology, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic); Havlik, Roman [Department of Surgery, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic); Kral, Vladimir [Department of Surgery, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic); Gryga, Adolf [Department of Surgery, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic); Duda, Miloslav [Department of Surgery, University Hospital, I.P.Pavlova 6, 775 20 Olomouc (Czech Republic)

    2007-05-15

    Purpose: To evaluate long-term results of treatment of benign bile duct strictures. Materials and methods: From February 1994 to November 2005, 21 patients (9 men, 12 women) with median age of 50.6 years (range 27-77 years) were indicated to percutaneous treatment of benign bile duct stricture. Stricture of hepatic ducts junction resulting from thermic injury during laparoscopic cholecystectomy was indication for treatment in one patient, stricture of hepaticojejunostomy was indication for treatment in all other patients. Clinical symptoms (obstructive jaundice, anicteric cholestasis, cholangitis or biliary cirrhosis) have appeared from 3 months to 12 years after surgery. Results: Initial internal/external biliary drainage was successful in 20 patients out of 21. These 20 patients after successful initial drainage were treated by balloon dilatation and long-term internal/external drainage. Sixteen patients were symptoms free during the follow-up. The relapse of clinical symptoms has appeared in four patients 9, 12, 14 and 24 months after treatment. One year primary clinical success rate of treatment for benign bile duct stricture was 94%. Additional two patients are symptoms free after redilatation (15 and 45 months). One patient is still in treatment, one patient died during secondary treatment period without interrelation with biliary intervention. The secondary clinical success rate is 100%. Conclusion: Benign bile duct strictures of hepatic ducts junction or biliary-enteric anastomosis are difficult to treat surgically and endoscopically inaccessible. Percutaneous treatment by balloon dilatation and long-term internal/external drainage is feasible in the majority of these patients. It is minimally invasive, safe and effective.

  18. Benign paroxysmal positional vertigo recurrence and persistence

    OpenAIRE

    Ricardo S. Dorigueto; Mazzetti,Karen R; Gabilan,Yeda Pereira L; Ganança, Fernando Freitas [UNIFESP

    2009-01-01

    Benign paroxysmal positional vertigo (BPPV) is one of the most common vestibular disorders. AIM: To study the recurrence and persistence of BPPV in patients treated with canalith repositioning maneuvers (CRM) during the period of one year. STUDY DESIGN: longitudinal contemporary cohort series. MATERIALS AND METHODS: One hundred patients with BPPV were followed up during 12 months after a treatment with CRM. Patients were classified according to disease evolution. Aquatic physiotherapy for ves...

  19. [Surgical treatment of benign paroxysmal positional vertigo].

    Science.gov (United States)

    Zaugg, Y; Grosjean, P; Maire, R

    2012-10-03

    Benign paroxysmal positional vertigo (BPPV) is a common disorder that presents to the general practitioner. This condition represents one of the most common causes of peripheral vertigo. The diagnosis is made on clinical grounds. The treatment relies on repositioning maneuvers with relief of symptoms that occur in a few weeks in the majority of the cases. Rarely, patients are incapacitated by persistent or recurrent BPPV despite multiple repositioning maneuvers. In these cases, surgical therapies are available which provide excellent results.

  20. Large Penile Mass With Unusual Benign Histopathology

    Directory of Open Access Journals (Sweden)

    Nate Johnson

    2015-09-01

    Full Text Available Pseudoepitheliomatous hyperplasia is an extremely rare condition presenting as a lesion on the glans penis in older men. Physical exam without biopsy cannot differentiate malignant from nonmalignant growth. We report a case of large penile mass in an elderly male with a history of lichen sclerosis, highly suspicious for malignancy. Subsequent surgical removal and biopsy demonstrated pseudoepitheliomatous hyperplasia, an unusual benign histopathologic diagnosis with unclear prognosis. We review the literature and discuss options for treatment and surveillance.

  1. [Benign prostatic hypertrophy and prostate cancer].

    Science.gov (United States)

    Mourey, Loïc; Doumerc, Nicolas; Gaudin, Clément; Gérard, Stéphane; Balardy, Laurent

    2014-01-01

    Prostatic diseases are extremely common, especially in older men. Amongst them, benign prostatic hypertrophy may affect significantly the quality of life of patients by the symptoms it causes. It requires appropriate care. Prostate cancer is the second most common cancer in men after lung cancer and the fifth leading cause of cancer deaths in the world. It affects preferentially older men. An oncogeriatric approach is required for personalised care.

  2. Approaches to verbal, visual and musical creativity by EEG coherence analysis.

    Science.gov (United States)

    Petsche, H

    1996-11-01

    Our approach to coherence analysis of the on-going EEG yields data on the cooperation between all possible electrode sites of the 10/20 system. This procedure compares epochs during mental activity with epochs of EEG at rest and takes into account only significant differences which are represented as lines between the respective electrodes on maps of the brain surface. The patterns thus obtained reflect the temporal average of the changes of the overall coherence pattern caused by any mental task. They are interpreted as reflecting differential attention required for the achievement of the mental task in question. Acts of creative thinking, be it verbally, visually or musically, are characterized by more coherence increases between occipital and frontopolar electrode sites than any other mental tasks. The results are interpreted by a stronger involvement of long cortico-cortical fibre systems in creative tasks.

  3. Laparoscopic resection of retroperitoneal benign neurilemmoma

    Science.gov (United States)

    Park, Joon Seong; Kang, Chang Moo; Yoon, Dong Sup; Lee, Woo Jung

    2017-01-01

    Purpose The aim of this study was to verify that laparoscopic resection for treating retroperitoneal benign neurilemmoma (NL) is expected to be favorable for complete resection of tumor with technical feasibility and safety. Methods We retrospectively analyzed 47 operations for retroperitoneal neurogenic tumor at Yonsei University College of Medicine, Severance Hospital and Gangnam Severance Hospital between January 2005 and September 2015. After excluding 21 patients, the remaining 26 were divided into 2 groups: those who underwent open surgery (OS) and those who underwent laparoscopic surgery (LS). We compared clinicopathological features between the 2 groups. Results There was no significant difference in operation time, estimated blood loss, transfusion, complication, recurrence, or follow-up period between 2 groups. Postoperative hospital stay was significantly shorter in the LS group versus the OS group (OS vs. LS, 7.00 ± 3.43 days vs. 4.50 ± 2.16 days; P = 0.031). Conclusion We suggest that laparoscopic resection of retroperitoneal benign NL is feasible and safe by obtaining complete resection of the tumor. LS for treating retroperitoneal benign NL could be useful with appropriate laparoscopic technique and proper patient selection.

  4. [Acute benign cerebral angiopathy. 6 cases].

    Science.gov (United States)

    Rousseaux, P; Scherpereel, B; Bernard, M H; Guyot, J F

    1983-10-08

    The 6 cases reported here constitute, with 5 previously published cases, a special nosological entity tentatively called "acute benign cerebral angiopathy" by the authors. These 11 cases have in common certain radiological and clinical features. Arteriography shows segmental, multifocal and assymetrical stenoses involving the cerebral arteries between Willis' circle and the terminal arterioles and looking like "strings of sausages". The lesions disappear within one month and present the radiological characteristics of arteritis of medium caliber vessels. The clinical symptoms are suggestive of meningeal haemorrhage or acute cerebromeningeal oedema, with acute repetitive attacks of severe headache and agitation with obnubilation; epileptic seizures and transient neurological deficit may occur. True meningeal haemorrhage confirmed by lumbar puncture is seen in nearly one half of the cases; it seems to be due to alterations in the blood-brain barrier induced by the angiopathy. Intracerebral haematoma may develop, but the disease is usually benign and regresses spontaneously in a few days. None of the usual causes of cerebral arteritis (intra-cranial infection, collagen disease, allergic or toxic angitis) has been found. Pseudo-arteritis (notably spasm of ruptured arterial aneurysms) has been excluded. No aetiological factor common to the 11 cases reported has been elicited, although 6 of the patients had recently given birth and our 6 patients had benign virus infection before or during the clinical manifestations of the disease. In the authors' opinion, the most rewarding line of research would be the role of short acute attacks of arterial hypertension.

  5. Environmentally benign silicon solar cell manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Tsuo, Y.S. [National Renewable Energy Lab., Golden, CO (United States); Gee, J.M. [Sandia National Labs., Albuquerque, NM (United States); Menna, P. [National Agency for New Technologies Energy and Environment, Portici (Italy); Strebkov, D.S.; Pinov, A.; Zadde, V. [Intersolarcenter, Moscow (Russian Federation)

    1998-09-01

    The manufacturing of silicon devices--from polysilicon production, crystal growth, ingot slicing, wafer cleaning, device processing, to encapsulation--requires many steps that are energy intensive and use large amounts of water and toxic chemicals. In the past two years, the silicon integrated-circuit (IC) industry has initiated several programs to promote environmentally benign manufacturing, i.e., manufacturing practices that recover, recycle, and reuse materials resources with a minimal consumption of energy. Crystalline-silicon solar photovoltaic (PV) modules, which accounted for 87% of the worldwide module shipments in 1997, are large-area devices with many manufacturing steps similar to those used in the IC industry. Obviously, there are significant opportunities for the PV industry to implement more environmentally benign manufacturing approaches. Such approaches often have the potential for significant cost reduction by reducing energy use and/or the purchase volume of new chemicals and by cutting the amount of used chemicals that must be discarded. This paper will review recent accomplishments of the IC industry initiatives and discuss new processes for environmentally benign silicon solar-cell manufacturing.

  6. Inhibitory effects of jujuboside A on EEG and hippocampal glutamate in hyperactive rat

    Institute of Scientific and Technical Information of China (English)

    LU Ying-jun; ZHOU Jun; ZHANG Shao-min; ZHANG Heng-yi; ZHENG Xiao-xiang

    2005-01-01

    In this study, the inhibitory effect ofjujuboside A (JuA) on a penicillin sodium (Na-PCN) induced hyperactivity model was investigated. Cortical EEG (electroencephalogram) and the concentration of hippocampal Glutamate (Glu) were monitored simultaneously in vivo as indicators of rat's excitatory state. Power spectral density (PSD) and gravity frequency of PSD were calculated. JuA (0.05 g/L and 0.1 g/L) inhibited the EEG excitation effect caused by Na-PCN by increasing the power of δ1 and δ2bands (P<0.01 vs model) and lowering the gravity frequency of PSD (P<0.01 vs model). JuA also remarkably reduced the Glu elevation induced by Na-PCN (P<0.05 vs model). Diazepam also depressed Glu concentration and lowered the gravity frequency,but it showed a different EEG pattern in increased β2-activity (P<0.01 vs model). EEG excitation caused by Na-PCN correlated with Glu elevation during the first hour. Neurophysiological inhibitory effects of JuA and diazepam were more persistent than their Glu inhibitoty effects.

  7. On the use of EEG or MEG brain imaging tools in neuromarketing research.

    Science.gov (United States)

    Vecchiato, Giovanni; Astolfi, Laura; De Vico Fallani, Fabrizio; Toppi, Jlenia; Aloise, Fabio; Bez, Francesco; Wei, Daming; Kong, Wanzeng; Dai, Jounging; Cincotti, Febo; Mattia, Donatella; Babiloni, Fabio

    2011-01-01

    Here we present an overview of some published papers of interest for the marketing research employing electroencephalogram (EEG) and magnetoencephalogram (MEG) methods. The interest for these methodologies relies in their high-temporal resolution as opposed to the investigation of such problem with the functional Magnetic Resonance Imaging (fMRI) methodology, also largely used in the marketing research. In addition, EEG and MEG technologies have greatly improved their spatial resolution in the last decades with the introduction of advanced signal processing methodologies. By presenting data gathered through MEG and high resolution EEG we will show which kind of information it is possible to gather with these methodologies while the persons are watching marketing relevant stimuli. Such information will be related to the memorization and pleasantness related to such stimuli. We noted that temporal and frequency patterns of brain signals are able to provide possible descriptors conveying information about the cognitive and emotional processes in subjects observing commercial advertisements. These information could be unobtainable through common tools used in standard marketing research. We also show an example of how an EEG methodology could be used to analyze cultural differences between fruition of video commercials of carbonated beverages in Western and Eastern countries.

  8. On the Use of EEG or MEG Brain Imaging Tools in Neuromarketing Research

    Directory of Open Access Journals (Sweden)

    Giovanni Vecchiato

    2011-01-01

    Full Text Available Here we present an overview of some published papers of interest for the marketing research employing electroencephalogram (EEG and magnetoencephalogram (MEG methods. The interest for these methodologies relies in their high-temporal resolution as opposed to the investigation of such problem with the functional Magnetic Resonance Imaging (fMRI methodology, also largely used in the marketing research. In addition, EEG and MEG technologies have greatly improved their spatial resolution in the last decades with the introduction of advanced signal processing methodologies. By presenting data gathered through MEG and high resolution EEG we will show which kind of information it is possible to gather with these methodologies while the persons are watching marketing relevant stimuli. Such information will be related to the memorization and pleasantness related to such stimuli. We noted that temporal and frequency patterns of brain signals are able to provide possible descriptors conveying information about the cognitive and emotional processes in subjects observing commercial advertisements. These information could be unobtainable through common tools used in standard marketing research. We also show an example of how an EEG methodology could be used to analyze cultural differences between fruition of video commercials of carbonated beverages in Western and Eastern countries.

  9. A post-stroke rehabilitation system integrating robotics, VR and high-resolution EEG imaging.

    Science.gov (United States)

    Steinisch, Martin; Tana, Maria Gabriella; Comani, Silvia

    2013-09-01

    We propose a system for the neuro-motor rehabilitation of upper limbs in stroke survivors. The system is composed of a passive robotic device (Trackhold) for kinematic tracking and gravity compensation, five dedicated virtual reality (VR) applications for training of distinct movement patterns, and high-resolution EEG for synchronous monitoring of cortical activity. In contrast to active devices, the Trackhold omits actuators for increased patient safety and acceptance levels, and for reduced complexity and costs. VR applications present all relevant information for task execution as easy-to-understand graphics that do not need any written or verbal instructions. High-resolution electroencephalography (HR-EEG) is synchronized with kinematic data acquisition, allowing for the epoching of EEG signals on the basis of movement-related temporal events. Two healthy volunteers participated in a feasibility study and performed a protocol suggested for the rehabilitation of post-stroke patients. Kinematic data were analyzed by means of in-house code. Open source packages (EEGLAB, SPM, and GMAC) and in-house code were used to process the neurological data. Results from kinematic and EEG data analysis are in line with knowledge from currently available literature and theoretical predictions, and demonstrate the feasibility and potential usefulness of the proposed rehabilitation system to monitor neuro-motor recovery.

  10. Assessing severity of obstructive sleep apnea by fractal dimension sequence analysis of sleep EEG

    Science.gov (United States)

    Zhang, J.; Yang, X. C.; Luo, L.; Shao, J.; Zhang, C.; Ma, J.; Wang, G. F.; Liu, Y.; Peng, C.-K.; Fang, J.

    2009-10-01

    Different sleep stages are associated with distinct dynamical patterns in EEG signals. In this article, we explored the relationship between the sleep architecture and fractal dimension (FD) of sleep EEG. In particular, we applied the FD analysis to the sleep EEG of patients with obstructive sleep apnea-hypopnea syndrome (OSAHS), which is characterized by recurrent oxyhemoglobin desaturation and arousals from sleep, a disease which received increasing public attention due to its significant potential impact on health. We showed that the variation of FD reflects the macrostructure of sleep. Furthermore, the fast fluctuation of FD, as measured by the zero-crossing rate of detrended FD (zDFD), is a useful indicator of sleep disturbance, and therefore, correlates with apnea-hypopnea index (AHI), and hourly number of blood oxygen saturation (SpO 2) decreases greater than 4%, as obstructive apnea/hypopnea disturbs sleep architecture. For practical purpose, a modified index combining zDFD of EEG and body mass index (BMI) may be useful for evaluating the severity of OSAHS symptoms.

  11. Feature Selection and Blind Source Separation in an EEG-Based Brain-Computer Interface

    Directory of Open Access Journals (Sweden)

    Michael H. Thaut

    2005-11-01

    Full Text Available Most EEG-based BCI systems make use of well-studied patterns of brain activity. However, those systems involve tasks that indirectly map to simple binary commands such as “yes” or “no” or require many weeks of biofeedback training. We hypothesized that signal processing and machine learning methods can be used to discriminate EEG in a direct “yes”/“no” BCI from a single session. Blind source separation (BSS and spectral transformations of the EEG produced a 180-dimensional feature space. We used a modified genetic algorithm (GA wrapped around a support vector machine (SVM classifier to search the space of feature subsets. The GA-based search found feature subsets that outperform full feature sets and random feature subsets. Also, BSS transformations of the EEG outperformed the original time series, particularly in conjunction with a subset search of both spaces. The results suggest that BSS and feature selection can be used to improve the performance of even a “direct,” single-session BCI.

  12. EEG. Renewables Act. Comment. 4. new rev. and enl. ed.; EEG. Erneuerbare-Energien-Gesetz. Kommentar

    Energy Technology Data Exchange (ETDEWEB)

    Frenz, Walter [RWTH Aachen Univ. (Germany). Lehr- und Forschungsgebiet Berg-, Umwelt- und Europarecht; Mueggenborg, Hans-Juergen [Technische Hochschule Aachen (Germany); Kassel Univ. (Germany); Cosack, Tilman [Hochschule Trier, Umwelt-Campus Birkenfeld (Germany). IREK - Inst. fuer das Recht der Erneuerbaren Energien, Energieeffizienzrecht und Klimaschutzrecht; Ekardt, Felix (ed.) [Forschungsstelle Nachhaltigkeit und Klimapolitik, Leipzig (Germany)

    2015-07-01

    Unlike any other Act, the Renewable Energy Sources Act (EEG) changes continuously. Recently it has been fundamentally transformed with the amendment 2014. Comprehensive, readable and practice-oriented. The proven Berliner comment EEG is your reliable companion through the new regulatory regime. All provisions of the EEG 2014 thorough and easy to understand commented by experts of the matter. 2. The EEG Amending Act of 29.6.2015 has already been considered. A detailed introduction and contributions to the relevant European law and the antitrust aspects of the renewable energy sources to guarantee you a broad understanding of the rules. Valuable background information you provide, the digressions of the most important renewable energy technologies, will explain the pictures thanks to numerous the scientific and technical foundations. Moreover you the construction law aspects in the construction of photovoltaic and wind turbines are explained clearly. [German] Wie kaum ein anderes Gesetz veraendert sich das Erneuerbare-Energien-Gesetz (EEG) laufend. Zuletzt wurde es mit der Novelle 2014 grundlegend umgestaltet. Umfassend, verstaendlich und praxisgerecht Der bewaehrte Berliner Kommentar EEG ist Ihr verlaesslicher Begleiter durch das neue Regelungsregime. Alle Vorschriften des EEG 2014 werden gruendlich und leicht verstaendlich von Kennern der Materie kommentiert. Das 2. EEG-Aenderungsgesetz vom 29.06.2015 ist bereits beruecksichtigt. Eine ausfuehrliche Einleitung sowie Beitraege zum einschlaegigen europaeischen Recht und zu den kartellrechtlichen Aspekten der erneuerbaren Energien verhelfen Ihnen zu einem breiten Verstaendnis der Vorschriften. Wertvolles Hintergrundwissen liefern Ihnen auch die Exkurse zu den wichtigsten Erneuerbare-Energien-Technologien, die Ihnen dank zahlreicher Abbildungen die naturwissenschaftlich-technischen Grundlagen erlaeutern. Zudem werden Ihnen die baurechtlichen Aspekte bei der Errichtung von Photovoltaik- und Windenergieanlagen

  13. Modification of EEG power spectra and EEG connectivity in autobiographical memory: a sLORETA study.

    Science.gov (United States)

    Imperatori, Claudio; Brunetti, Riccardo; Farina, Benedetto; Speranza, Anna Maria; Losurdo, Anna; Testani, Elisa; Contardi, Anna; Della Marca, Giacomo

    2014-08-01

    The aim of the present study was to explore the modifications of scalp EEG power spectra and EEG connectivity during the autobiographical memory test (AM-T) and during the retrieval of an autobiographical event (the high school final examination, Task 2). Seventeen healthy volunteers were enrolled (9 women and 8 men, mean age 23.4 ± 2.8 years, range 19-30). EEG was recorded at baseline and while performing the autobiographical memory (AM) tasks, by means of 19 surface electrodes and a nasopharyngeal electrode. EEG analysis was conducted by means of the standardized LOw Resolution Electric Tomography (sLORETA) software. Power spectra and lagged EEG coherence were compared between EEG acquired during the memory tasks and baseline recording. The frequency bands considered were as follows: delta (0.5-4 Hz); theta (4.5-7.5 Hz); alpha (8-12.5 Hz); beta1 (13-17.5 Hz); beta2 (18-30 Hz); gamma (30.5-60 Hz). During AM-T, we observed a significant delta power increase in left frontal and midline cortices (T = 3.554; p < 0.05) and increased EEG connectivity in delta band in prefrontal, temporal, parietal, and occipital areas, and for gamma bands in the left temporo-parietal regions (T = 4.154; p < 0.05). In Task 2, we measured an increased power in the gamma band located in the left posterior midline areas (T = 3.960; p < 0.05) and a significant increase in delta band connectivity in the prefrontal, temporal, parietal, and occipital areas, and in the gamma band involving right temporo-parietal areas (T = 4.579; p < 0.05). These results indicate that AM retrieval engages in a complex network which is mediated by both low- (delta) and high-frequency (gamma) EEG bands.

  14. Target Speaker Detection with Concealed EEG Around the Ear

    Science.gov (United States)

    Mirkovic, Bojana; Bleichner, Martin G.; De Vos, Maarten; Debener, Stefan

    2016-01-01

    Target speaker identification is essential for speech enhancement algorithms in assistive devices aimed toward helping the hearing impaired. Several recent studies have reported that target speaker identification is possible through electroencephalography (EEG) recordings. If the EEG system could be reduced to acceptable size while retaining the signal quality, hearing aids could benefit from the integration with concealed EEG. To compare the performance of a multichannel around-the-ear EEG system with high-density cap EEG recordings an envelope tracking algorithm was applied in a competitive speaker paradigm. The data from 20 normal hearing listeners were concurrently collected from the traditional state-of-the-art laboratory wired EEG system and a wireless mobile EEG system with two bilaterally-placed around-the-ear electrode arrays (cEEGrids). The results show that the cEEGrid ear-EEG technology captured neural signals that allowed the identification of the attended speaker above chance-level, with 69.3% accuracy, while cap-EEG signals resulted in the accuracy of 84.8%. Further analyses investigated the influence of ear-EEG signal quality and revealed that the envelope tracking procedure was unaffected by variability in channel impedances. We conclude that the quality of concealed ear-EEG recordings as acquired with the cEEGrid array has potential to be used in the brain-computer interface steering of hearing aids. PMID:27512364

  15. The Role of Imitation in the Observed Heterogeneity in EEG Mu Rhythm in Autism and Typical Development

    Science.gov (United States)

    Bernier, Raphael; Aaronson, Benjamin; McPartland, James

    2013-01-01

    Dysfunction in an execution/observation matching system, or mirror neuron system, has been proposed to contribute to the social deficits observed in Autism Spectrum Disorder (ASD). Atypical activity in this system, as reflected in attenuation of the EEG mu rhythm, has been demonstrated in several studies; however, normative patterns of activity…

  16. EEG Based Inference of Spatio-Temporal Brain Dynamics

    DEFF Research Database (Denmark)

    Hansen, Sofie Therese

    recovery ability. The forward problem describes the propagation of neuronal activity in the brain to the EEG electrodes on the scalp. The geometry and conductivity of the head layers are normally required to model this path. We propose a framework for inferring forward models which is based on the EEG......Electroencephalography (EEG) provides a measure of brain activity and has improved our understanding of the brain immensely. However, there is still much to be learned and the full potential of EEG is yet to be realized. In this thesis we suggest to improve the information gain of EEG using three....... The main topic of this thesis is the localization of the EEG generators. This entails solving both a forward and an inverse problem. The inverse problem maps the EEG signal recorded on the scalp to its origin in the brain. It is a highly ill-posed problem which we tackle by employing a sparsity promoting...

  17. Resting and reactive frontal brain electrical activity (EEG among a non-clinical sample of socially anxious adults: Does concurrent depressive mood matter?

    Directory of Open Access Journals (Sweden)

    Elliott A Beaton

    2008-03-01

    Full Text Available Elliott A Beaton1, Louis A Schmidt2, Andrea R Ashbaugh2,5, Diane L Santesso2, Martin M Antony1,3,4, Randi E McCabe1,31Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario, Canada; 2Department of Psychology, Neuroscience and Behaviour, McMaster University, Hamilton, Ontario, Canada; 3Anxiety Treatment and Research Centre, St. Joseph’s Healthcare, Hamilton, Ontario, Canada; 4Department of Psychology, Ryerson University, Toronto, Ontario, Canada; 5Concordia University, Montreal, Quebec, CanadaAbstract: A number of studies have noted that the pattern of resting frontal brain electrical activity (EEG is related to individual differences in affective style in healthy infants, children, and adults and some clinical populations when symptoms are reduced or in remission. We measured self-reported trait shyness and sociability, concurrent depressive mood, and frontal brain electrical activity (EEG at rest and in anticipation of a speech task in a non-clinical sample of healthy young adults selected for high and low social anxiety. Although the patterns of resting and reactive frontal EEG asymmetry did not distinguish among individual differences in social anxiety, the pattern of resting frontal EEG asymmetry was related to trait shyness after controlling for concurrent depressive mood. Individuals who reported a higher degree of shyness were likely to exhibit greater relative right frontal EEG activity at rest. However, trait shyness was not related to frontal EEG asymmetry measured during the speech-preparation task, even after controlling for concurrent depressive mood. These findings replicate and extend prior work on resting frontal EEG asymmetry and individual differences in affective style in adults. Findings also highlight the importance of considering concurrent emotional states of participants when examining psychophysiological correlates of personality.Keywords: social anxiety, shyness, sociability

  18. Reliability of quantitative EEG (qEEG) measures and LORETA current source density at 30 days.

    Science.gov (United States)

    Cannon, Rex L; Baldwin, Debora R; Shaw, Tiffany L; Diloreto, Dominic J; Phillips, Sherman M; Scruggs, Annie M; Riehl, Timothy C

    2012-06-14

    There is a growing interest for using quantitative EEG and LORETA current source density in clinical and research settings. Importantly, if these indices are to be employed in clinical settings then the reliability of these measures is of great concern. Neuroguide (Applied Neurosciences) is sophisticated software developed for the analyses of power, and connectivity measures of the EEG as well as LORETA current source density. To date there are relatively few data evaluating topographical EEG reliability contrasts for all 19 channels and no studies have evaluated reliability for LORETA calculations. We obtained 4 min eyes-closed and eyes-opened EEG recordings at 30-day intervals. The EEG was analyzed in Neuroguide and FFT power, coherence and phase was computed for traditional frequency bands (delta, theta, alpha and beta) and LORETA current source density was calculated in 1 Hz increments and summed for total power in eight regions of interest (ROI). In order to obtain a robust measure of reliability we utilized a random effects model with an absolute agreement definition. The results show very good reproducibility for total absolute power and coherence. Phase shows lower reliability coefficients. LORETA current source density shows very good reliability with an average 0.81 for ECB and 0.82 for EOB. Similarly, the eight regions of interest show good to very good agreement across time. Implications for future directions and use of qEEG and LORETA in clinical populations are discussed.

  19. Discriminant Multitaper Component Analysis of EEG

    DEFF Research Database (Denmark)

    Dyrholm, Mads; Sajda, Paul

    the method for predicting the handedness of a subject’s button press given multivariate EEG data. We show that our method learns multitapers sensitive to oscillatory activity in the 8–12 Hz range with spatial filters selective for lateralized motor cortex. This finding is consistent with the well-known mu...

  20. EEG source imaging during two Qigong meditations.

    Science.gov (United States)

    Faber, Pascal L; Lehmann, Dietrich; Tei, Shisei; Tsujiuchi, Takuya; Kumano, Hiroaki; Pascual-Marqui, Roberto D; Kochi, Kieko

    2012-08-01

    Experienced Qigong meditators who regularly perform the exercises "Thinking of Nothing" and "Qigong" were studied with multichannel EEG source imaging during their meditations. The intracerebral localization of brain electric activity during the two meditation conditions was compared using sLORETA functional EEG tomography. Differences between conditions were assessed using t statistics (corrected for multiple testing) on the normalized and log-transformed current density values of the sLORETA images. In the EEG alpha-2 frequency, 125 voxels differed significantly; all were more active during "Qigong" than "Thinking of Nothing," forming a single cluster in parietal Brodmann areas 5, 7, 31, and 40, all in the right hemisphere. In the EEG beta-1 frequency, 37 voxels differed significantly; all were more active during "Thinking of Nothing" than "Qigong," forming a single cluster in prefrontal Brodmann areas 6, 8, and 9, all in the left hemisphere. Compared to combined initial-final no-task resting, "Qigong" showed activation in posterior areas whereas "Thinking of Nothing" showed activation in anterior areas. The stronger activity of posterior (right) parietal areas during "Qigong" and anterior (left) prefrontal areas during "Thinking of Nothing" may reflect a predominance of self-reference, attention and input-centered processing in the "Qigong" meditation, and of control-centered processing in the "Thinking of Nothing" meditation.

  1. Music Shifts Frontal EEG in Depressed Adolescents.

    Science.gov (United States)

    Field, Tiffany; Martinez, Alex; Nawrocki, Thomas; Pickens, Jeffrey; Fox, Nathan A.; Schanberg, Saul

    1998-01-01

    Fourteen chronically depressed female adolescents listened to rock music for a 23-minute session. EEG was recorded and saliva samples were collected to determine the effects of the music on stress hormone cortisol levels. No differences were reported for mood state; however, cortisol levels decreased and relative right-frontal activation was…

  2. Correlation between intra- and extracranial background EEG

    DEFF Research Database (Denmark)

    Duun-Henriksen, Jonas; Kjaer, Troels W.; Madsen, Rasmus E.;

    2012-01-01

    Scalp EEG is the most widely used modality to record the electrical signals of the brain. It is well known that the volume conduction of these brain waves through the brain, cerebrospinal fluid, skull and scalp reduces the spatial resolution and the signal amplitude. So far the volume conduction ...

  3. EEG-based characterization of flicker perception

    NARCIS (Netherlands)

    Lazo, M.; Tsoneva, T.; Garcia Molina, G.

    2013-01-01

    Steady-State Visual Evoked Potential (SSVEP) is an oscillatory electrical response appearing in the electroencephalogram (EEG) in response to flicker stimulation. The SSVEP manifests more prominently in electrodes located near the visual cortex and has oscillatory components at the stimulation frequ

  4. Objective Audiometry using Ear-EEG

    DEFF Research Database (Denmark)

    Christensen, Christian Bech; Kidmose, Preben

    therefore be an enabling technology for objective audiometry out of the clinic, allowing regularly fitting of the hearing aids to be made by the users in their everyday life environment. The objective of this study is to investigate the application of ear-EEG in objective audiometry....

  5. Source localization of rhythmic ictal EEG activity

    DEFF Research Database (Denmark)

    Beniczky, Sándor; Lantz, Göran; Rosenzweig, Ivana

    2013-01-01

    Although precise identification of the seizure-onset zone is an essential element of presurgical evaluation, source localization of ictal electroencephalography (EEG) signals has received little attention. The aim of our study was to estimate the accuracy of source localization of rhythmic ictal ...

  6. Assessment of the EEG complexity during activations from sleep.

    Science.gov (United States)

    Chouvarda, I; Rosso, V; Mendez, M O; Bianchi, A M; Parrino, L; Grassi, A; Terzano, M; Cerutti, S

    2011-12-01

    The present study quantitatively analyzes the EEG characteristics during activations (Act) that occur during NREM sleep, and constitute elements of sleep microstructure (i.e. the Cyclic Alternating Pattern). The fractal dimension (FD) and the sample entropy (SampEn) measures were used to study the different sleep stages and the Act that build up the sleep structure. Polysomnographic recordings from 10 good sleepers were analyzed. The complexity indexes of the Act were compared with the non-activation (NAct) periods during non-REM sleep. In addition, complexity measures among the different Act subtypes (A1, A2 and A3) were analyzed. A3 presented a quite similar complexity independently of the sleep stage, while A1 and A2 showed higher complexity in light sleep than during deep sleep. The current results suggest that Act present a hierarchic complexity between subtypes A3 (higher), A2 (intermediate) and A1 (lower) in all sleep stages.

  7. Binge Drinking Effects on EEG in Young Adult Humans

    Directory of Open Access Journals (Sweden)

    Kelly E. Courtney

    2010-05-01

    Full Text Available Young adult (N = 96 university students who varied in their binge drinking history were assessed by electroencephalography (EEG recording during passive viewing. Groups consisted of male and female non-binge drinkers (>1 to 5/4 drinks/ounces in under two hours, low-binge drinkers (5/4–7/6 drinks/ounces in under two hours, and high-binge drinkers (≥ 10 drinks/ounces in under two hours, who had been drinking alcohol at their respective levels for an average of 3 years. The non- and low-binge drinkers exhibited less spectral power than the high-binge drinkers in the delta (0–4 Hz and fast-beta (20–35 Hz bands. Binge drinking appears to be associated with a specific pattern of brain electrical activity in young adults that may reflect the future development of alcoholism.

  8. Investigating social cognition in infants and adults using dense array electroencephalography ((d)EEG).

    Science.gov (United States)

    Akano, Adekemi J; Haley, David W; Dudek, Joanna

    2011-06-27

    Dense array electroencephalography ((d)EEG), which provides a non-invasive window for measuring brain activity and a temporal resolution unsurpassed by any other current brain imaging technology¹, ² is being used increasingly in the study of social cognitive functioning in infants and adults. While (d)EEG is enabling researchers to examine brain activity patterns with unprecedented levels of sensitivity, conventional EEG recording systems continue to face certain limitations, including 1) poor spatial resolution and source localization³,⁴2) the physical discomfort for test subjects of enduring the individual application of numerous electrodes to the surface of the scalp, and 3) the complexity for researchers of learning to use multiple software packages to collect and process data. Here we present an overview of an established methodology that represents a significant improvement on conventional methodologies for studying EEG in infants and adults. Although several analytical software techniques can be used to establish indirect indices of source localization to improve the spatial resolution of (d)EEG, the HydroCel Geodesic Sensor Net (HCGSN) by Electrical Geodesics, Inc. (EGI), a dense sensory array that maintains equal distances among adjacent recording electrodes on all surfaces of the scalp, further enhances spatial resolution⁴,⁵(,)⁶ compared to standard (d)EEG systems. The sponge-based HCGSN can be applied rapidly and without scalp abrasion, making it ideal for use with adults⁷,⁸ children⁹,¹⁰, ¹¹,¹² and infants¹², in both research and clinical ⁴,⁵,⁶,¹³,¹⁴,¹⁵settings. This feature allows for considerable cost and time savings by decreasing the average net application time compared to other (d)EEG systems. Moreover, the HCGSN includes unified, seamless software applications for all phases of data, greatly simplifying the collection, processing, and analysis of (d)EEG data. The HCGSN features a low-profile electrode

  9. EEG differences as a function of creativity, stage of the creative process, and effort to be original.

    Science.gov (United States)

    Martindale, C; Hasenfus, N

    1978-04-01

    Results of two experiments examining the relationship between creativity and EEG alpha wave presence are reported. In Experiment 1, it was found that more creative subjects exhibited higher alpha indices during an analogue of creative inspiration than during an analogue of creative elaboration. This pattern was not found in less creative subjects. In Experiment 2 a similar effect was found in a more controlled setting and shown to be specific to creative subjects when they are instructed to be original but not when they are given no such instructions. No consistent relationship between creativity and basal EEG alpha activity was found.

  10. Predictive value of the amplitude integrated EEG in infants with hypoxic ischaemic encephalopathy: data from a randomised trial of therapeutic hypothermia.

    Science.gov (United States)

    Azzopardi, Denis

    2014-01-01

    The amplitude integrated EEG (aEEG) is reputed to be one of the best predictors of neurological outcome following hypoxic ischaemic encephalopathy in term newborns and was used to select infants into trials of neuroprotection with hypothermia, but its predictive value and the effect of moderate hypothermia on the aEEG have not previously been examined in a randomised study. The positive predictive value (PPV) of the aEEG recorded within 6 h of birth for death or disability at 18 months of age was determined in 314 infants born after 35 weeks gestation who were randomised to receive standard care with or without cooling for 72 h. The aEEG was classified according to voltage and by pattern. The PPV of a severely abnormal aEEG assessed by the voltage and pattern methods was 0.63 and 0.59 respectively in non-cooled infants and 0.55 and 0.51 in cooled infants (p>0.05). Although the differences in PPV between cooled and non-cooled groups were not significant, they are consistent with observational studies showing a lower PPV in infants treated with hypothermia, probably due to a neuroprotective effect of cooling.

  11. Brain Network Analysis from High-Resolution EEG Signals

    Science.gov (United States)

    de Vico Fallani, Fabrizio; Babiloni, Fabio

    Over the last decade, there has been a growing interest in the detection of the functional connectivity in the brain from different neuroelectromagnetic and hemodynamic signals recorded by several neuro-imaging devices such as the functional Magnetic Resonance Imaging (fMRI) scanner, electroencephalography (EEG) and magnetoencephalography (MEG) apparatus. Many methods have been proposed and discussed in the literature with the aim of estimating the functional relationships among different cerebral structures. However, the necessity of an objective comprehension of the network composed by the functional links of different brain regions is assuming an essential role in the Neuroscience. Consequently, there is a wide interest in the development and validation of mathematical tools that are appropriate to spot significant features that could describe concisely the structure of the estimated cerebral networks. The extraction of salient characteristics from brain connectivity patterns is an open challenging topic, since often the estimated cerebral networks have a relative large size and complex structure. Recently, it was realized that the functional connectivity networks estimated from actual brain-imaging technologies (MEG, fMRI and EEG) can be analyzed by means of the graph theory. Since a graph is a mathematical representation of a network, which is essentially reduced to nodes and connections between them, the use of a theoretical graph approach seems relevant and useful as firstly demonstrated on a set of anatomical brain networks. In those studies, the authors have employed two characteristic measures, the average shortest path L and the clustering index C, to extract respectively the global and local properties of the network structure. They have found that anatomical brain networks exhibit many local connections (i.e. a high C) and few random long distance connections (i.e. a low L). These values identify a particular model that interpolate between a regular

  12. Sparse Bayesian Learning for Obtaining Sparsity of EEG Frequency Bands Based Feature Vectors in Motor Imagery Classification.

    Science.gov (United States)

    Zhang, Yu; Wang, Yu; Jin, Jing; Wang, Xingyu

    2017-03-01

    Effective common spatial pattern (CSP) feature extraction for motor imagery (MI) electroencephalogram (EEG) recordings usually depends on the filter band selection to a large extent. Subband optimization has been suggested to enhance classification accuracy of MI. Accordingly, this study introduces a new method that implements sparse Bayesian learning of frequency bands (named SBLFB) from EEG for MI classification. CSP features are extracted on a set of signals that are generated by a filter bank with multiple overlapping subbands from raw EEG data. Sparse Bayesian learning is then exploited to implement selection of significant features with a linear discriminant criterion for classification. The effectiveness of SBLFB is demonstrated on the BCI Competition IV IIb dataset, in comparison with several other competing methods. Experimental results indicate that the SBLFB method is promising for development of an effective classifier to improve MI classification.

  13. EEG indices in patients with high risk of ischemic stroke as predictors of initial disturbed cerebral circulation

    Directory of Open Access Journals (Sweden)

    N. A. Isaeva

    2014-01-01

    Full Text Available Abnormal changes were detected in EEG in patients with high risk of ischemic stroke (higher level than in the population. These changes show the disturbances in forming mechanisms of functional condition of cerebrum during the calm wakeful period. Changes were represented by: the registration of EEG IV- type (the E.A. Zhirmunsky type which was characterized by disorganization of alpha activity and of slow waves; the instability of pattern during the record of background activity; the paroxysmal activity in form of flashes of the bilateral synchronized waves; the strengthening of low-frequency and high-amplitude β-activity. Revealed changes in EEG show the presence of initial disturbed cerebral circulation and can be recommended as predictors of these disturbances.

  14. Guiding transcranial brain stimulation by EEG/MEG to interact with ongoing brain activity and associated functions

    DEFF Research Database (Denmark)

    Thut, Gregor; Bergmann, Til Ole; Fröhlich, Flavio

    2017-01-01

    Non-invasive transcranial brain stimulation (NTBS) techniques have a wide range of applications but also suffer from a number of limitations mainly related to poor specificity of intervention and variable effect size. These limitations motivated recent efforts to focus on the temporal dimension...... of NTBS with respect to the ongoing brain activity. Temporal patterns of ongoing neuronal activity, in particular brain oscillations and their fluctuations, can be traced with electro- or magnetoencephalography (EEG/MEG), to guide the timing as well as the stimulation settings of NTBS. These novel, online...... and offline EEG/MEG-guided NTBS-approaches are tailored to specifically interact with the underlying brain activity. Online EEG/MEG has been used to guide the timing of NTBS (i.e., when to stimulate): by taking into account instantaneous phase or power of oscillatory brain activity, NTBS can be aligned...

  15. Neonatal epilepsy and underlying aetiology: to what extent do seizures and EEG abnormalities influence outcome?

    Science.gov (United States)

    Ramantani, Georgia

    2013-12-01

    Neonatal seizures constitute the most common and distinctive sign of neurological dysfunction in the first weeks of life and reflect a wide variety of underlying central nervous system disorders. Acute symptomatic seizures occur more often during the neonatal period than at any period of life and are associated with adverse long-term neurodevelopmental sequelae and an increased risk of post-neonatal epilepsy. The improvements of neonatal care in the last decades have changed the spectrum of insults to which the immature brain is exposed and facilitated a decrease in mortality of newborns with seizures. However, the prevalence of long-term morbidity in survivors remains unchanged. Whereas aetiology is presumed to be the main predictor of long-term outcome in neonates with seizures, there is converging evidence that specific electroencephalographic (EEG) abnormalities are related to unfavourable outcomes. Interictal EEG abnormalities, especially concerning background activity patterns, thus constitute a major indicator of disease severity and predictor of outcome, while the added value of sequential EEG assessments is so far controversial. Moreover, experimental as well as clinical studies of hypoxic-ischaemic encephalopathy support the notion that recurrent seizures may amplify injury to the developing brain beyond that associated with the underlying aetiology, thus justifying antiepileptic drug treatment. To date, unresolved issues in seizure detection and classification, in addition to the significant variation in gestational ages and brain insults of neonates, still impede clinical research of neonatal seizures. The wider use of long-term EEG or amplitude integrated EEG monitoring may prove crucial for timely neonatal seizure identification and treatment initiation, and thus ultimately improve outcome.

  16. Decoding sequence learning from single-trial intracranial EEG in humans.

    Directory of Open Access Journals (Sweden)

    Marzia De Lucia

    Full Text Available We propose and validate a multivariate classification algorithm for characterizing changes in human intracranial electroencephalographic data (iEEG after learning motor sequences. The algorithm is based on a Hidden Markov Model (HMM that captures spatio-temporal properties of the iEEG at the level of single trials. Continuous intracranial iEEG was acquired during two sessions (one before and one after a night of sleep in two patients with depth electrodes implanted in several brain areas. They performed a visuomotor sequence (serial reaction time task, SRTT using the fingers of their non-dominant hand. Our results show that the decoding algorithm correctly classified single iEEG trials from the trained sequence as belonging to either the initial training phase (day 1, before sleep or a later consolidated phase (day 2, after sleep, whereas it failed to do so for trials belonging to a control condition (pseudo-random sequence. Accurate single-trial classification was achieved by taking advantage of the distributed pattern of neural activity. However, across all the contacts the hippocampus contributed most significantly to the classification accuracy for both patients, and one fronto-striatal contact for one patient. Together, these human intracranial findings demonstrate that a multivariate decoding approach can detect learning-related changes at the level of single-trial iEEG. Because it allows an unbiased identification of brain sites contributing to a behavioral effect (or experimental condition at the level of single subject, this approach could be usefully applied to assess the neural correlates of other complex cognitive functions in patients implanted with multiple electrodes.

  17. Interictal functional connectivity of human epileptic networks assessed by intracerebral EEG and BOLD signal fluctuations.

    Directory of Open Access Journals (Sweden)

    Gaelle Bettus

    Full Text Available In this study, we aimed to demonstrate whether spontaneous fluctuations in the blood oxygen level dependent (BOLD signal derived from resting state functional magnetic resonance imaging (fMRI reflect spontaneous neuronal activity in pathological brain regions as well as in regions spared by epileptiform discharges. This is a crucial issue as coherent fluctuations of fMRI signals between remote brain areas are now widely used to define functional connectivity in physiology and in pathophysiology. We quantified functional connectivity using non-linear measures of cross-correlation between signals obtained from intracerebral EEG (iEEG and resting-state functional MRI (fMRI in 5 patients suffering from intractable temporal lobe epilepsy (TLE. Functional connectivity was quantified with both modalities in areas exhibiting different electrophysiological states (epileptic and non affected regions during the interictal period. Functional connectivity as measured from the iEEG signal was higher in regions affected by electrical epileptiform abnormalities relative to non-affected areas, whereas an opposite pattern was found for functional connectivity measured from the BOLD signal. Significant negative correlations were found between the functional connectivities of iEEG and BOLD signal when considering all pairs of signals (theta, alpha, beta and broadband and when considering pairs of signals in regions spared by epileptiform discharges (in broadband signal. This suggests differential effects of epileptic phenomena on electrophysiological and hemodynamic signals and/or an alteration of the neurovascular coupling secondary to pathological plasticity in TLE even in regions spared by epileptiform discharges. In addition, indices of directionality calculated from both modalities were consistent showing that the epileptogenic regions exert a significant influence onto the non epileptic areas during the interictal period. This study shows that functional

  18. The role of the standard EEG in clinical psychiatry.

    LENUS (Irish Health Repository)

    O'Sullivan, S S

    2012-02-03

    BACKGROUND: The EEG is a commonly requested test on patients attending psychiatric services, predominantly to investigate for a possible organic brain syndrome causing behavioural changes. AIMS: To assess referrals for EEG from psychiatric services in comparison with those from other sources. We determine which clinical factors were associated with an abnormal EEG in patients referred from psychiatric sources. METHODS: A retrospective review of EEG requests in a 1-year period was performed. Analysis of referral reasons for psychiatric patients was undertaken, and outcome of patients referred from psychiatric services post-EEG was reviewed. RESULTS: One thousand four hundred and seventy EEGs were reviewed, of which 91 (6.2%) were referred from psychiatry. Neurology service referrals had detection rates of abnormal EEGs of 27%, with psychiatric referrals having the lowest abnormality detection rate of 17.6% (p < 0.1). In psychiatric-referred patients the only significant predictors found of an abnormal EEG were a known history of epilepsy (p < 0.001), being on clozapine (p < 0.05), and a possible convulsive seizure (RR = 6.51). Follow-up data of 53 patients did not reveal a significant clinical impact of EEG results on patient management. CONCLUSIONS: Many patients are referred for EEG from psychiatric sources despite a relatively low index of suspicion of an organic brain disorders, based on reasons for referral documented, with an unsurprising low clinical yield.

  19. A personalized history of EEG-fMRI integration.

    Science.gov (United States)

    Laufs, Helmut

    2012-08-15

    In this personalized review, the history of EEG recorded simultaneously with functional MRI (EEG-fMRI) is summarized. A brief overview is given of the hardware development followed by a discussion of EEG-fMRI applications. The technique's development was clinically motivated in the context of epilepsy. Accordingly, the evolution of studies trying to identify with EEG-fMRI the origin of individual epileptiform discharges up to those revealing general mechanisms of epilepsy syndromes is sketched. In epilepsy centers experienced with the methodology, EEG-fMRI has found its place in the presurgical evaluation of patients. In cognitive neuroscience, the multimodal technique has significantly contributed to the understanding of phenomena of the resting state and neuronal oscillations. While most of the studies discussed relate EEG to fMRI by means of prediction, the development of forward models facilitating the symmetrical 'fusion' of EEG and fMRI data is the subject of current neuro-computational research. Recently, intracranial EEG has been safely recorded during (functional) MRI broadly extending the perspectives for epilepsy and research into neurovascular coupling. EEG-fMRI has evolved into a mature, generally accessible and in principle easily applicable technique, which is a great achievement. Because this at the same time bears the risk of unreflected use, EEG-fMRI safety issues are also highlighted.

  20. A Bayes optimal matrix-variate LDA for extraction of spatio-spectral features from EEG signals.

    Science.gov (United States)

    Mahanta, Mohammad Shahin; Aghaei, Amirhossein S; Plataniotis, Konstantinos N

    2012-01-01

    Classification of mental states from electroencephalogram (EEG) signals is used for many applications in areas such as brain-computer interfacing (BCI). When represented in the frequency domain, the multichannel EEG signal can be considered as a two-directional spatio-spectral data of high dimensionality. Extraction of salient features using feature extractors such as the commonly used linear discriminant analysis (LDA) is an essential step for the classification of these signals. However, multichannel EEG is naturally in matrix-variate format, while LDA and other traditional feature extractors are designed for vector-variate input. Consequently, these methods require a prior vectorization of the EEG signals, which ignores the inherent matrix-variate structure in the data and leads to high computational complexity. A matrix-variate formulation of LDA have previously been proposed. However, this heuristic formulation does not provide the Bayes optimality benefits of LDA. The current paper proposes a Bayes optimal matrix-variate formulation of LDA based on a matrix-variate model for the spatio-spectral EEG patterns. The proposed formulation also provides a strategy to select the most significant features among the different rows and columns.

  1. Spatial contrast sensitivity in benign intracranial hypertension.

    Science.gov (United States)

    Bulens, C; Meerwaldt, J D; Koudstaal, P J; Van der Wildt, G J

    1988-01-01

    Spatial Contrast Sensitivity (CS) was studied in 20 patients with benign intracranial hypertension (BIH). At presentation CS loss was found in 43% of the eyes, and impairment of visual acuity attributed to BIH in only 16%. Nine patients had blurred vision or visual obscurations, all of whom had abnormal CS. The clinical application of CS measurement in BIH for monitoring the progression or regression of the disease is illustrated by serial measurements in 11 patients. Progressive visual loss in longstanding papilloedema and improvement of visual function in subsiding papilloedema can occur without any change in Snellen acuity or visual field charting. PMID:3225588

  2. Spatial contrast sensitivity in benign intracranial hypertension.

    Science.gov (United States)

    Bulens, C; Meerwaldt, J D; Koudstaal, P J; Van der Wildt, G J

    1988-10-01

    Spatial Contrast Sensitivity (CS) was studied in 20 patients with benign intracranial hypertension (BIH). At presentation CS loss was found in 43% of the eyes, and impairment of visual acuity attributed to BIH in only 16%. Nine patients had blurred vision or visual obscurations, all of whom had abnormal CS. The clinical application of CS measurement in BIH for monitoring the progression or regression of the disease is illustrated by serial measurements in 11 patients. Progressive visual loss in longstanding papilloedema and improvement of visual function in subsiding papilloedema can occur without any change in Snellen acuity or visual field charting.

  3. Benign symmetric lipomatosis of the knees

    Institute of Scientific and Technical Information of China (English)

    Zhiqiang Yin; Di Wu; Yixin Ge; Meihua Zhang; Zhigang Bi; Dan Luo

    2008-01-01

    Benign symmetric lipomatosis(BSL) is a rare disease characterized by the presence of multiple, symmetric and nonencapsulated fat masses in the face, neck and other areas. It is commonly seen in middle-aged Caucasian Mediterranean males, while its etiology is still not clear. The majority of the patients with BSL have a history of alcohol abuse and hepatopathy. BSL of the limbs is very rare. This article reports a unique case of a 60-year-old Chinese woman with involvement of the knees confirmed by the results of magnetic resonance imaging(MRI) and histopathology, which was not described previously in published literatures.

  4. Clarithromycin Culprit of Benign Intracranial Hypertension

    Directory of Open Access Journals (Sweden)

    Habib Rehman Khan

    2015-01-01

    Full Text Available Benign intracranial hypertension is characterized with increase in CSF opening pressure with no specific etiology. It is predominantly found in women of child bearing age and particularly in individuals with obesity. Visual disturbances or loss and associated headaches are common and can lead to blindness if left untreated. Diagnosis can be achieved once other causes of visual loss, headaches and high opening pressures are excluded. Management consists of serial optic disc assessments although no specific treatment is available despite recent trials using carbonic anhydrase inhibitors. Diet modification and weight management can help in therapy.

  5. Incidence of epileptiform EEG activity in children during mask induction of anaesthesia with brief administration of 8% sevoflurane.

    Directory of Open Access Journals (Sweden)

    Barbara Schultz

    Full Text Available BACKGROUND: A high incidence of epileptiform activity in the electroencephalogram (EEG was reported in children undergoing mask induction of anaesthesia with administration of high doses of sevoflurane for 5 minutes and longer. This study was performed to investigate whether reducing the time of exposure to a high inhaled sevoflurane concentration would affect the incidence of epileptiform EEG activity. It was hypothesized that no epileptiform activity would occur, when the inhaled sevoflurane concentration would be reduced from 8% to 4% immediately after the loss of consciousness. METHODOLOGY/PRINCIPAL FINDINGS: 70 children (age 7-96 months, ASA I-II, premedication with midazolam were anaesthetized with 8% sevoflurane in 100% oxygen via face mask. Immediately after loss of consciousness, the sevoflurane concentration was reduced to 4%. EEGs were recorded continuously and were later analyzed visually with regard to epileptiform EEG patterns. Sevoflurane at a concentration of 8% was given for 1.2 ± 0.4 min (mean ± SD. In 14 children (20% epileptiform EEG patterns without motor manifestations were observed (delta with spikes (DSP, rhythmic polyspikes (PSR, epileptiform discharges (PED in 10, 10, 4 children (14%, 14%, 6%. 38 children (54% had slow, rhythmic delta waves with high amplitudes (DS appearing on average before DSP. CONCLUSIONS/SIGNIFICANCE: The hypothesis that no epileptiform potentials would occur during induction of anaesthesia with a reduction of the inspired sevoflurane concentration from 8% to 4% directly after LOC was not proved. Even if 8% sevoflurane is administered only briefly for induction of anaesthesia, epileptiform EEG activity may be observed in children despite premedication with midazolam.

  6. Ultrasonographic Findings of the Prostatic Disease : Comparative Analysis of the Benign and Malignant Nodules

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yun Gyu; Kim, Ji Yang; Lee, Su Han; Kong, Su Jin; Sung, Young Soon; Kwon, Jae Soo [Masan Samsung General Hospital, Masan (Korea, Republic of)

    1996-06-15

    We evaluated the characteristics of the benign and malignant nodules on transrectal ultrasound in diagnosis of prostatic disease. Histologic examination of the trans perineal prostatic biopsy of the total 47 cases resulted in 19 cases of BPH, 8 cases of prostatic cancer, and 20 cases of normal prostatic tissue group. The hypoechoic mass in peripheral zone on TRUS had high possibility of prostatic carcinoma and the isoechoic or mixed echogenic mass in central gland had high possibility of benign lesion. Hypoechoic haloes around nodules and cysts were noted in BPH and normal prostatic tissue group, that were compatible with benign lesion. The mean value of PSA was 12.0 ng/ ml in BPH, 8.5 ng / ml in normal prostatic tissue group, and 65.6 ng / ml in prostatic cancer, which was very high in prostatic cancer. Between BPH and normal prostatic tissue group, there was no demonstrable difference in location of nodule, pattern of calcification, and echogenicity of the nodules on TRUS. The size of prostatic gland was relatively smaller and mean value of PSA was lower in normal prostatic tissue group, compared with in BPH. In conclusion, the location of the nodules and PSA value are considered to be important in differentiation of the benign and malignant prostatic nodules

  7. Clinical Value of Contrast-enhanced Ultrasound in Differentiating Benign and Malignant Focal Liver Lesions

    Institute of Scientific and Technical Information of China (English)

    XU Jinfeng; WU Ying; DONG Fajin; XIONG Yi; PENG Qihui; XIE Mingxing

    2007-01-01

    To explore the clinical value of contrast-enhanced ultrasound (CEUS) in differentiating benign and malignant focal liver lesions (FLLs) with SonoVue, CEUS was used to examine 113 pa- tients with focal liver lesions (FLLs) in our hospital during July 2005 to December 2006. All the pa- tients underwent contrast-enhanced CT (CECT) or contrast-enhanced MRI(CEMRI). Except for pa- tients with focal fatty sparings (n=18) and with hemangiomas (n=8), all the patients were confirmed by operation or ultrasonic-guided liver puncture biopsy. A sulfur hexafluoride gas-based contrast agent was used with a MI of 0.15 to 0.17. Forty-eight cases of malignant FLLs, including 30 hepato- cellular carcinomas (HCCs), 2 cholangiocarcinomas and 16 metastatic tumors, were detected. Sev- enty-eight cases of benign FLLs, including 33 hemangiomas, 9 focal nodular hyperplasias (FNHs), 19 focal fatty sparings, 5 abscesses, 7 regenerative nodules and 2 inflammatory pseudo-tumor, were in- volved. The contrast pattern of benign and malignant FLLs was quite different. CEUS has higher specificity and sensitivity than conventional ultrasound in differentiating benign and malignant FLLs.

  8. Family history of cancer in benign brain tumor subtypes versus gliomas

    Directory of Open Access Journals (Sweden)

    Quinn eOstrom

    2012-02-01

    Full Text Available Purpose: Family history is associated with gliomas, but this association has not ben established for benign brain tumors. Using information from newly diagnosed primary brain tumor patients, we describe patterns of family cancer histories in patients with benign brain tumors and compare those to patients with gliomas. Methods: Newly diagnosed primary brain tumor patients were identified as part of the Ohio Brain Tumor Study (OBTS. Each patient was asked to participate in a telephone interview about personal medical history, family history of cancer, and other exposures. Information was available from 33 acoustic neuroma (65%, 78 meningioma (65%, 49 pituitary adenoma (73.1% and 152 glioma patients (58.2%. The association between family history of cancer and each subtype was compared with gliomas using unconditional logistic regression models generating odds ratios (ORs and 95% confidence intervals (95% CI. Results: There was no significant difference in family history of cancer between patients with glioma and benign subtypes. Conclusions: The results suggest that benign brain tumor may have an association with family history of cancer. More studies are warranted to disentangle the potential genetic and/or environmental causes for these diseases.

  9. Donepezil impairs memory in healthy older subjects: behavioural, EEG and simultaneous EEG/fMRI biomarkers.

    Directory of Open Access Journals (Sweden)

    Joshua H Balsters

    Full Text Available Rising life expectancies coupled with an increasing awareness of age-related cognitive decline have led to the unwarranted use of psychopharmaceuticals, including acetylcholinesterase inhibitors (AChEIs, by significant numbers of healthy older individuals. This trend has developed despite very limited data regarding the effectiveness of such drugs on non-clinical groups and recent work indicates that AChEIs can have negative cognitive effects in healthy populations. For the first time, we use a combination of EEG and simultaneous EEG/fMRI to examine the effects of a commonly prescribed AChEI (donepezil on cognition in healthy older participants. The short- and long-term impact of donepezil was assessed using two double-blind, placebo-controlled trials. In both cases, we utilised cognitive (paired associates learning (CPAL and electrophysiological measures (resting EEG power that have demonstrated high-sensitivity to age-related cognitive decline. Experiment 1 tested the effects of 5 mg/per day dosage on cognitive and EEG markers at 6-hour, 2-week and 4-week follow-ups. In experiment 2, the same markers were further scrutinised using simultaneous EEG/fMRI after a single 5 mg dose. Experiment 1 found significant negative effects of donepezil on CPAL and resting Alpha and Beta band power. Experiment 2 replicated these results and found additional drug-related increases in the Delta band. EEG/fMRI analyses revealed that these oscillatory differences were associated with activity differences in the left hippocampus (Delta, right frontal-parietal network (Alpha, and default-mode network (Beta. We demonstrate the utility of simple cognitive and EEG measures in evaluating drug responses after acute and chronic donepezil administration. The presentation of previously established markers of age-related cognitive decline indicates that AChEIs can impair cognitive function in healthy older individuals. To our knowledge this is the first study to identify

  10. Biogas plants in EEG. 4. new rev. and enl. ed.; Biogasanlagen im EEG

    Energy Technology Data Exchange (ETDEWEB)

    Loibl, Helmut; Maslaton, Martin; Bredow, Hartwig von; Walter, Rene (eds.)

    2016-08-01

    With the EEG 2014, the legislature has created a complete revision of all the RES plants. Specifically for biogas plants fundamental changes have been made with the maximum rated power or a new landscape conservation concept. For new biogas plants the legislator arranges not only a much lower remuneration, but also the direct marketing as a rule, which entails fundamental changes in the overall compensation system by itself. The new edition of this highly regarded standard work revives the extensive practical experience to EEG 2009, 2012 and 2014 in detail and in particular and takes into account the large number of newly issued clearinghouses decisions and judgments. All current legal issues and challenges of biogas plants can be found comprehensively presented here. [German] Mit dem EEG 2014 hat der Gesetzgeber eine komplette Neuregelung fuer alle EEG-Anlagen geschaffen. Speziell fuer Biogasanlagen wurden mit der Hoechstbemessungsleistung oder einem neuen Landschaftspflegebegriff grundlegende Aenderungen vorgenommen. Fuer neue Biogasanlagen ordnet der Gesetzgeber nicht nur eine deutlich geringere Verguetung, sondern zudem die Direktvermarktung als Regelfall an, was grundlegende Veraenderungen des gesamten Verguetungssystems nach sich zieht. Die Neuauflage dieses vielbeachteten Standardwerks greift die umfangreichen Praxiserfahrungen zum EEG 2009, 2012 und 2014 detailliert auf und beruecksichtigt insbesondere auch die Vielzahl der neu ergangenen Clearingstellenentscheidungen und Urteile. Alle aktuellen rechtlichen Themen und Herausforderungen bei Biogasanlagen finden Sie hier umfassend dargestellt.

  11. Benign cementoblastoma (true cementoma in a cat

    Directory of Open Access Journals (Sweden)

    Lenin A Villamizar-Martinez

    2016-01-01

    Full Text Available Case summary A 10-year-old castrated male domestic shorthair cat was presented for assessment of a gingival mass surrounding the left maxillary third and fourth premolar teeth. The mass was surgically removed by means of a marginal rim excision, and the tissue was submitted for histological assessment. It was identified as a benign cementoblastoma (true cementoma. There was proliferation of mineralized eosinophilic material with multiple irregularly placed lacunae and reversal lines, reminiscent of cementum. The cat recovered uneventfully from the anesthesia, and there was no evidence of tumor recurrence 6 months after surgery. Relevance and novel information Cementoblastomas (true cementomas in domestic animals are rare, with just a few reports in ruminants, monogastric herbivores and rodents. Cementoblastoma is considered a benign tumor that arises from the tooth root. The slow, expansive and constant growth that characterizes these masses may be accompanied by signs of oral discomfort and dysphagia. This case report is intended to increase knowledge regarding this tumor in cats and also highlights the importance of complete excision of the neoplasm. To our knowledge, there are no previous reports in the literature of cementoblastoma in the cat.

  12. Extended seizure detection algorithm for intracranial EEG recordings

    DEFF Research Database (Denmark)

    Kjaer, T. W.; Remvig, L. S.; Henriksen, J.

    2010-01-01

    Objective: We implemented and tested an existing seizure detection algorithm for scalp EEG (sEEG) with the purpose of improving it to intracranial EEG (iEEG) recordings. Method: iEEG was obtained from 16 patients with focal epilepsy undergoing work up for resective epilepsy surgery. Each patient...... had 4 or 5 recorded seizures and 24 hours of non-ictal data were used for evaluation. Data from three electrodes placed at the ictal focus were used for the analysis. A wavelet based feature extraction algorithm delivered input to a support vector machine (SVM) classifier for distinction between ictal...... the original implementation a sensitivity of 92.8% and a false positive ratio (FPR) of 0.93/h were obtained. Our extension of the algorithm rendered a 95.9% sensitivity and only 0.65 false detections per hour. Conclusion: Better seizure detection can be performed when the higher frequencies in the iEEG were...

  13. Data-driven forward model inference for EEG brain imaging

    DEFF Research Database (Denmark)

    Hansen, Sofie Therese; Hauberg, Søren; Hansen, Lars Kai

    2016-01-01

    Electroencephalography (EEG) is a flexible and accessible tool with excellent temporal resolution but with a spatial resolution hampered by volume conduction. Reconstruction of the cortical sources of measured EEG activity partly alleviates this problem and effectively turns EEG into a brain......-of-concept study, we show that, even when anatomical knowledge is unavailable, a suitable forward model can be estimated directly from the EEG. We propose a data-driven approach that provides a low-dimensional parametrization of head geometry and compartment conductivities, built using a corpus of forward models....... Combined with only a recorded EEG signal, we are able to estimate both the brain sources and a person-specific forward model by optimizing this parametrization. We thus not only solve an inverse problem, but also optimize over its specification. Our work demonstrates that personalized EEG brain imaging...

  14. Visualization of EEG using time-frequency distributions.

    Science.gov (United States)

    Stiber, B Z; Sato, S

    1997-12-01

    The EEG is a time-varying or nonstationary signal. Frequency and amplitude are two of its significant characteristics, and are valuable clues to different states of brain activity. Detection of these temporal features is important in understanding EEGs. Commonly, spectrograms and AR models are used for EEG analysis. However, their accuracy is limited by their inherent assumption of stationarity and their trade-off between time and frequency resolution. We investigate EEG signal processing using existing compound kernel time-frequency distributions (TFDs). By providing a joint distribution of signal intensity at any frequency along time, TFDs preserve details of the temporal structure of the EEG waveform, and can extract its time-varying frequency and amplitude features. We expect that this will have significant implications for EEG analysis and medical diagnosis.

  15. EEG activity during estral cycle in the rat.

    Science.gov (United States)

    Corsi-Cabrera, M; Juárez, J; Ponce-de-León, M; Ramos, J; Velázquez, P N

    1992-10-01

    EEG activity was recorded from right and left parietal cortex in adult female rats daily during 6 days. Immediately after EEG recording vaginal smears were taken and were microscopically analyzed to determine the estral stage. Absolute and relative powers and interhemispheric correlation of EEG activity were calculated and compared between estral stages. Interhemispheric correlation was significantly lower during diestrous as compared to proestrous and estrous. Absolute and relative powers did not show significant differences between estral stages. Absolute powers of alpha1, alpha2, beta1 and beta2 bands were significantly higher at the right parietal cortex. Comparisons of the same EEG records with estral stages randomly grouped showed no significant differences for any of the EEG parameters. EEG activity is a sensitive tool to study functional changes related to the estral cycle.

  16. Memories of attachment hamper EEG cortical connectivity in dissociative patients.

    Science.gov (United States)

    Farina, Benedetto; Speranza, Anna Maria; Dittoni, Serena; Gnoni, Valentina; Trentini, Cristina; Vergano, Carola Maggiora; Liotti, Giovanni; Brunetti, Riccardo; Testani, Elisa; Della Marca, Giacomo

    2014-08-01

    In this study, we evaluated cortical connectivity modifications by electroencephalography (EEG) lagged coherence analysis, in subjects with dissociative disorders and in controls, after retrieval of attachment memories. We asked thirteen patients with dissociative disorders and thirteen age- and sex-matched healthy controls to retrieve personal attachment-related autobiographical memories through adult attachment interviews (AAI). EEG was recorded in the closed eyes resting state before and after the AAI. EEG lagged coherence before and after AAI was compared in all subjects. In the control group, memories of attachment promoted a widespread increase in EEG connectivity, in particular in the high-frequency EEG bands. Compared to controls, dissociative patients did not show an increase in EEG connectivity after the AAI. Conclusions: These results shed light on the neurophysiology of the disintegrative effect of retrieval of traumatic attachment memories in dissociative patients.

  17. A Study of the effect of sound on EEG

    Directory of Open Access Journals (Sweden)

    Renu Bhoria,

    2013-01-01

    Full Text Available This paper presents a brief study of various effects of sound on the human brain activity. This can be shown through the study of EEG signal recorded. The effect is in the form of variation in either frequency or in the power of different EEG bands. A biomedical signal electroencephalography (EEG reflects the state of mind and is often used to verify the influence of music on human brain activity. In fact EEG signals are related to the characteristic parameters of brain electrical activity. Moreover as our mind state changes EEG changes accordingly. The raw EEG cannot be observed or used efficiently. Hence various techniques like time frequency analysis has been employed to read the effects.

  18. Classification of EEG with structural feature dictionaries in a brain computer interface.

    Science.gov (United States)

    Göksu, Fikri; Ince, Nuri Firat; Tadipatri, Vijay Aditya; Tewfik, Ahmed H

    2008-01-01

    We present a new method for the classification of EEG in a brain computer interface by adapting subject specific features in spectral, temporal and spatial domain. For this particular purpose we extend our previous work on ECoG classification based on structural feature dictionary and apply it to extract the spectro-temporal patterns of multichannel EEG recordings related to a motor imagery task. The construction of the feature dictionary based on undecimated wavelet packet transform is extended to block FFT. We evaluate several subset selection algorithms to select a small number of features for final classification. We tested our proposed approach on five subjects of BCI Competition 2005 dataset- IVa. By adapting the wavelet filter for each subject, the algorithm achieved an average classification accuracy of 91.4% The classification results and characteristic of selected features indicate that the proposed algorithm can jointly adapt to EEG patterns in spectro-spatio-temporal domain and provide classification accuracies as good as existing methods used in the literature.

  19. Spatiotemporal Analysis of Multichannel EEG: CARTOOL

    OpenAIRE

    Denis Brunet; Murray, Micah M; Michel, Christoph M.

    2011-01-01

    This paper describes methods to analyze the brain's electric fields recorded with multichannel Electroencephalogram (EEG) and demonstrates their implementation in the software CARTOOL. It focuses on the analysis of the spatial properties of these fields and on quantitative assessment of changes of field topographies across time, experimental conditions, or populations. Topographic analyses are advantageous because they are reference independents and thus render statistically unambiguous resul...

  20. EEG alpha power and creative ideation ☆

    OpenAIRE

    2014-01-01

    Neuroscientific studies revealed first insights into neural mechanisms underlying creativity, but existing findings are highly variegated and often inconsistent. Despite the disappointing picture on the neuroscience of creativity drawn in recent reviews, there appears to be robust evidence that EEG alpha power is particularly sensitive to various creativity-related demands involved in creative ideation. Alpha power varies as a function of creativity-related task demands and the originality of...

  1. Qualitative and quantitative EEG in psychotic children.

    Science.gov (United States)

    Itil, T M; Simeon, J; Coffin, C

    1976-05-01

    The EEGs of hospitalized psychotic boys were analyzed quantitatively by means of visual evaluation, analog frequency analysis, and digital computer period analysis and were compared with those of age- and sex-matched normals. Visual evaluation of the records demonstrated that psychotic children have significantly more beta activity as well as fewer alpha bursts than normal controls. EEG analog frequency analysis showed that psychotic children have a greater percentage of total voltage in the 3-5 cps and 13-33 cps bands, while they show less voltage in the 6-12 cps bands as compared with normal controls. Digital computer period analysis demonstrated more slow, less alpha, and more fast activity, as well as a greater average frequency and frequency deviation in both the primary wave and first derivative measurements in psychotic children than normals, while normals showed a trend towards higher amplitude and amplitude variability. The similarity of the EEG differences between psychotic and normal children to those differences observed between adult chronic schizophrenics and normals, as well as to those between children of "high risk" for becoming schizophrenic and controls, suggests that the above described findings are characteristic for the pathophysiology of schizophrenia.

  2. EEG workload prediction in a closed-loop learning environment

    OpenAIRE

    2015-01-01

    The issues of developing an online EEG-based adaptive learning environment are examined in this thesis. The aim is to adapt instructional learning material in real-time, to support learners in their individual learning process and keep them in their optimal workload capacity range during learning. First, suitable learning material is designed, which does not cause artifacts and induces confounds in the EEG data. Second, the most suitable features for an online workload detection in EEG data a...

  3. Use of EEG to Track Visual Attention in Two Dimensions

    Science.gov (United States)

    2014-05-01

    ABSTRACT 16. SECURITY CLASSIFICATION OF: This thesis investigates the use of EEG to track the spatial locus of covert, visual attention. Three experiments...UU UU UU UU 15-04-2015 Approved for public release; distribution is unlimited. Use of EEG to track visual attention in two dimensions The views...P.O. Box 12211 Research Triangle Park, NC 27709-2211 EEG attention vision REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 10

  4. Scale-invariance of human EEG signals in sleep

    CERN Document Server

    Cai, S M; Wang, B H; Yang, H J; Zhou, P L; Zhou, T; Cai, Shi-Min; Jiang, Zhao-Hui; Wang, Bing-Hong; Yang, Hui-Jie; Zhou, Pei-Ling; Zhou, Tao

    2007-01-01

    We investigate the dynamical properties of electroencephalogram (EEG) signals of human in sleep. By using a modified random walk method, We demonstrate that the scale-invariance is embedded in EEG signals after a detrending procedure. Further more, we study the dynamical evolution of probability density function (PDF) of the detrended EEG signals by nonextensive statistical modeling. It displays scale-independent property, which is markedly different from the turbulent-like scale-dependent PDF evolution.

  5. Transfer function between EEG and BOLD signals of epileptic activity

    Directory of Open Access Journals (Sweden)

    Marco eLeite

    2013-01-01

    Full Text Available Simultaneous EEG-fMRI recordings have seen growing application in the evaluation of epilepsy, namely in the characterization of brain networks related to epileptic activity. In EEG-correlated fMRI studies, epileptic events are usually described as boxcar signals based on the timing information retrieved from the EEG, and subsequently convolved with a heamodynamic response function to model the associated BOLD changes. Although more flexible approaches may allow a higher degree of complexity for the haemodynamics, the issue of how to model these dynamics based on the EEG remains an open question. In this work, a new methodology for the integration of simultaneous EEG-fMRI data in epilepsy is proposed, which incorporates a transfer function from the EEG to the BOLD signal. Independent component analysis (ICA of the EEG is performed, and a number of metrics expressing different models of the EEG-BOLD transfer function are extracted from the resulting time courses. These metrics are then used to predict the fMRI data and to identify brain areas associated with the EEG epileptic activity. The methodology was tested on both ictal and interictal EEG-fMRI recordings from one patient with a hypothalamic hamartoma. When compared to the conventional analysis approach, plausible, consistent and more significant activations were obtained. Importantly, frequency-weighted EEG metrics yielded superior results than those weighted solely on the EEG power, which comes in agreement with previous literature. Reproducibility, specificity and sensitivity should be addressed in an extended group of patients in order to further validate the proposed methodology and generalize the presented proof of concept.

  6. Detection the Character Wave in Epileptic EEG by Wavelet

    Institute of Scientific and Technical Information of China (English)

    CHEN Huafu; NIU Hai

    2004-01-01

    Human epilepsy is an intrinsic brain pathology,which can be characterized by repetitive high-amplitude electroencephalograph (EEG) activity.The wavelet transform provides an important tool in signal analysis and feature extraction.In this paper,the modulus maximum pair of a wavelet transform is used to detect the singularity value of the sharps and the spikes embedded in the background activities of the epilepsy EEG.The efficacy of the proposed method has been tested with clinical EEG.

  7. Benign and malignant tumors of the foot and ankle

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Adam D.; Datir, Abhijit; Langley, Travis [Emory University Hospital, Department of Radiology, Section of Musculoskeletal Imaging, Atlanta, GA (United States); Tresley, Jonathan [University of Wisconsin, Department of Radiology, Madison, WI (United States); Clifford, Paul D.; Jose, Jean; Subhawong, Ty K. [University of Miami, Department of Radiology, Miami, FL (United States)

    2016-03-15

    Pain and focal masses in the foot and ankle are frequently encountered and often initiate a workup including imaging. It is important to differentiate benign lesions from aggressive benign or malignant lesions. In this review, multiple examples of osseous and soft tissue tumors of the foot and ankle will be presented. Additionally, the compartmental anatomy of the foot and ankle will be discussed in terms of its relevance for percutaneous biopsy planning and eventual surgery. Finally, a general overview of the surgical management of benign, benign aggressive and malignant tumors of the foot and ankle will be discussed. (orig.)

  8. The appendix: a spectrum of benign and malignant disease.

    Science.gov (United States)

    Lord, Christopher; Broadhurst, Jack; Sleight, Simon; McGee, Shaun; Wills, Mark

    2017-02-02

    This article discusses the radiological appearances and subsequent management of a diverse spectrum of benign and malignant appendiceal pathologies, including those masquerading as acute appendicitis.

  9. Clustered microcalcifications without mass on mammography : benignancy vs. malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Han, Yoon Hee; Do, Young Soo; Oh, Hoon Il; Kim, Ki Hwan; Chin, Soo Yil [Korean Cancer Center Hostpital, Seoul (Korea, Republic of); Cho, Byung Jae [Chung Dam Radiologic Clinics, Seoul (Korea, Republic of); Han, Heon [Chungang Gil Hospital, Seoul (Korea, Republic of); Choi, Yeun Hyeun; Han, Boo Kyung [Sam Sung Medical Center, Seoul (Korea, Republic of); Park, Jung Mi [Asan Medical Center, Seoul (Korea, Republic of)

    1996-11-01

    The purpose of this study is to evaluate the accuracy of differentiation between benign and malignant clustered microcalcifications without mass on mammogram. Fourty six mammograms of 44 patients showing clustered microcalcifications without mass were interpreted blindly by five independent observers majoring in breast imaging from different institutions. Twenty two were malignant (10 infiltrating ductal carcinomas, 12 intraductal carcinomas) and 24 were benign (all fibrocystic disease). The observers judge benignancy or malignancy of microcalcifications. The authors assess the accuracy of differential diagnosis of clustered microcalcifications. Of 24 cases proved benign microcalcifications, five radiologists correctly interpreted 20 on average as benign and of malignant 22 cases, 16 on average were correctly interpreted as malignant. The diagnostic accuracy of malignant microcalcifications was 71.8% on average(63.6%{approx}81.8%) and the diagnostic accuracy for benign microcalcifications was 83% on average(71%{approx}92%). It was 9 among total 46 cases that were misinterpreted by more than three radiologists. Among these 9 cases, malignant microcalcifications that had been misinterpreted as benign were seven, benign microcalcifications misinterpreted as malignant were two. The diagnostic accuracy of clustered malignant microcalcifications(71.8%) without mass on mammogram was lower than that of benign microcalcifications(83.3%). So, in case of suspected malignant microcalcification on mammogram, it is preferable that along with magnification view, histopathologic confirmation by core biopsy must be obtained.

  10. EEG sensorimotor correlates of translating sounds into actions

    Directory of Open Access Journals (Sweden)

    Jaime A. Pineda

    2013-12-01

    Full Text Available Understanding the actions of others is a necessary foundational cornerstone for effective and affective social interactions. Such understanding may result from a mapping of observed actions as well as heard sounds onto one’s own motor representations of those events. To examine the electrophysiological basis of action-related sounds, EEG data were collected in two studies from adults who were exposed to auditory events in one of three categories: action (either hand- or mouth-based sounds, non-action (environmental sounds, and control sounds (scrambled versions of action sounds. In both studies, triplets of sounds of the same category were typically presented, although occasionally, to insure an attentive state, trials containing a sound from a different category were presented within the triplet and participants were asked to respond to this oddball event either covertly in one study or overtly in another. Additionally, participants in both studies were asked to mimic hand- and mouth-based motor actions associated with the sounds (motor task. Action sounds elicited larger EEG mu rhythm (8-13 Hz suppression, relative to control sounds, primarily over left hemisphere, while non-action sounds showed larger mu suppression primarily over right hemisphere. Furthermore, hand-based sounds elicited greater mu suppression over the hand area in sensorimotor cortex compared to mouth-based sounds. These patterns of mu suppression across cortical regions to different categories of sounds and to effector-specific sounds suggest differential engagement of a mirroring system in the human brain when processing sounds.

  11. Preliminary Study on Quantitative Sleep EEG Characteristics in Patients with Schizophrenia

    Science.gov (United States)

    Oh, Seong Min; Kim, Jong Won; Choi, Jae Won; Jeong, Do-Un

    2017-01-01

    We used quantitative electroencephalography (EEG) spectral analysis to compare activity in the bilateral frontal, central, and occipital areas in nine patients with schizophrenia and ten healthy control subjects during standard nocturnal polysomnography. Patients with schizophrenia had longer sleep latency than controls. In N2 sleep, the patients had significantly lower 0.5–1 Hz power and higher theta power in the left frontal region, and higher beta power in the left occipital region than did control subjects. In N3 sleep, the patients with schizophrenia had significantly higher alpha power in the left occipital region than did controls. These findings show distinctive EEG sleep patterns in patients with schizophrenia, which may reflect brain dysfunction or medication effects.

  12. Time sparsification of EEG signals in motor-imagery based brain computer interfaces.

    Science.gov (United States)

    Higashi, Hiroshi; Tanaka, Toshihisa

    2012-01-01

    We propose a method of sparsifying EEG signals in the time domain for common spatial patterns (CSP) which are often used for feature extraction in brain computer interfaces (BCI). For accurate classification, it is important to analyze the period of time when a BCI user performs a mental task. We address this problem by optimizing the CSP cost with a time sparsification that removes unnecessary samples from the classification. We design a cost function that has CSP spatial weights and time window as optimization parameters. To find these parameters, we use alternating optimization. In an experiment on classification of motor-imagery EEG signals, the proposed method increased classification accuracy by 6% averaged over five subjects.

  13. Focal epilepsies: HM-PAO SPECT compared with CT, MR, and EEG.

    Science.gov (United States)

    Cordes, M; Christe, W; Henkes, H; Delavier, U; Eichstädt, H; Schörner, W; Langer, R; Felix, R

    1990-01-01

    Regional cerebral blood flow (rCBF) was evaluated quantitatively by 99mTc hexamethyl propyleneamine oxime and single photon emission CT (SPECT) during the interictal phase in 52 patients with focal epilepsy. The results were compared with those obtained by electroencephalography (EEG), CT, and magnetic resonance (MR) imaging. Twenty-four of the 52 patients had one area of local hypoperfusion whereas 7 patients showed an area of local hyperperfusion. In 20 of the 52 patients, both reduced and elevated rCBF values were found. One patient had a normal perfusion pattern. The SPECT findings correlated well with the foci shown by EEG, both with regard to the sides affected and the locations of the regions of altered perfusion. The MR images showed focal lesions in only approximately one-half of the patients examined, and CT in even fewer.

  14. Automatic detection of EEG artefacts arising from head movements using EEG and gyroscope signals.

    Science.gov (United States)

    O'Regan, Simon; Faul, Stephen; Marnane, William

    2013-07-01

    Contamination of EEG signals by artefacts arising from head movements has been a serious obstacle in the deployment of automatic neurological event detection systems in ambulatory EEG. In this paper, we present work on categorizing these head-movement artefacts as one distinct class and on using support vector machines to automatically detect their presence. The use of additional physical signals in detecting head-movement artefacts is also investigated by means of support vector machines classifiers implemented with gyroscope waveforms. Finally, the combination of features extracted from EEG and gyroscope signals is explored in order to design an algorithm which incorporates both physical and physiological signals in accurately detecting artefacts arising from head-movements.

  15. Memory performance on the California Verbal Learning Test of children with benign childhood epilepsy with centrotemporal spikes.

    Science.gov (United States)

    Vago, Chiara; Bulgheroni, Sara; Franceschetti, Silvana; Usilla, Arianna; Riva, Daria

    2008-11-01

    Verbal learning and retrieval, as well as the use of learning strategies, were assessed in 24 children with benign epilepsy with centrotemporal spikes (BECTS) and 16 controls, using the California Verbal Learning Test-Children's Version. Neuropsychological data were correlated with EEG features. Compared with age-matched controls, the children with BECTS younger than 10 exhibited significant learning difficulties and were less efficient in using a semantic clustering strategy, whereas no such difference emerged for subjects older than 10. This suggests that the capacity for spontaneous use of a more efficient strategy matures later in children with BECTS. Moreover, the majority of those younger than 10 had multifocal anomalies, suggesting that the difficulties encountered might be caused by the presence of additional foci.

  16. EEG simulation by 2D interconnected chaotic oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Kubany, Adam, E-mail: adamku@bgu.ac.i [Department of Industrial Engineering and Management, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105 (Israel); Mhabary, Ziv; Gontar, Vladimir [Department of Industrial Engineering and Management, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105 (Israel)

    2011-01-15

    Research highlights: ANN of 2D interconnected chaotic oscillators is explored for EEG simulation. An inverse problem solution (PRCGA) is proposed. Good matching between the simulated and experimental EEG signals has been achieved. - Abstract: An artificial neuronal network composed by 2D interconnected chaotic oscillators is explored for brain waves (EEG) simulation. For the inverse problem solution a parallel real-coded genetic algorithm (PRCGA) is proposed. In order to conduct thorough comparison between the simulated and target signal characteristics, a spectrum analysis of the signals is undertaken. A good matching between the theoretical and experimental EEG signals has been achieved. Numerical results of calculations are presented and discussed.

  17. EEG signal features extraction based on fractal dimension.

    Science.gov (United States)

    Finotello, Francesca; Scarpa, Fabio; Zanon, Mattia

    2015-01-01

    The spread of electroencephalography (EEG) in countless applications has fostered the development of new techniques for extracting synthetic and informative features from EEG signals. However, the definition of an effective feature set depends on the specific problem to be addressed and is currently an active field of research. In this work, we investigated the application of features based on fractal dimension to a problem of sleep identification from EEG data. We demonstrated that features based on fractal dimension, including two novel indices defined in this work, add valuable information to standard EEG features and significantly improve sleep identification performance.

  18. Persistent positional nystagmus: a case of superior semicircular canal benign paroxysmal positional vertigo?

    Science.gov (United States)

    Heidenreich, Katherine D; Kerber, Kevin A; Carender, Wendy J; Basura, Gregory J; Telian, Steven A

    2011-08-01

    Involvement of the superior semicircular canal (SSC) in benign paroxysmal positional vertigo (BPPV) is rare. SSC BPPV is distinguished from the more common posterior semicircular canal (PSC) variant by the pattern of nystagmus triggered by the Dix-Hallpike position: down-beating torsional nystagmus in SSC BPPV versus up-beating torsional nystagmus in PSC BPPV. SSC BPPV may be readily treated at the bedside, which is a key component in excluding central causes of down-beating nystagmus. We present an unusual video case report believed to represent refractory SSC BPPV based on the pattern of nystagmus and the absence of any other central signs.

  19. Evaluation of partial epilepsy in Iran: role of video-EEG, EEG, and MRI with epilepsy protocol

    OpenAIRE

    Parastoo Faraji; Mahsa Mousavi; Mohammad Hossein Harirchian; Hossein Ali Ghelichnia Omrani; Majid Ghaffarpour; Amir Hossein Modabbernia; Vajiheh Aghamollaii; Abbas Tafakhori

    2011-01-01

    Background We evaluated the diagnostic value of Electroencephalography (EEG), video-EEG monitoring (VEM) and Magnetic resonance imaging (MRI) of the brain with epilepsy protocol in patients with complex partial epilepsy. Methods Forty-two consecutive patients underwent complete neurological examination, EEG, and MRI with a modified epilepsy protocol. A subset of these patients (n = 29) also underwent VEM. Data were presented using descriptive statistics and were analyzed using Chi square and ...

  20. Mean-field modeling of thalamocortical dynamics and a model-driven approach to EEG analysis.

    Science.gov (United States)

    Victor, Jonathan D; Drover, Jonathan D; Conte, Mary M; Schiff, Nicholas D

    2011-09-13

    Higher brain function depends on task-dependent information flow between cortical regions. Converging lines of evidence suggest that interactions between cortical regions and the central thalamus play a key role in establishing the dynamic patterns of functional connectivity that normally support these processes. In patients with chronic disturbances of cognitive function due to severe brain injury, dysfunction of this circuitry likely plays a crucial role in pathogenesis. However, assaying thalamocortical interactions is challenging even in healthy subjects and more so in severely impaired patients. To approach this problem, we apply a dynamical-systems approach to motivate an analysis of the electroencephalogram (EEG). We begin with a model for a single thalamocortical module [Robinson PA, Rennie CJ, Rowe DL (2002) Phys Rev E Stat Nonlin Soft Matter Phys 65:041924; Robinson PA, Rennie CJ, Wright JJ, Bourke PD (1998) Phys Rev E Stat Nonlin Soft Matter Phys 58:3557-3571]. When two such modules interact via shared thalamic inhibition, multistable behavior emerges; each mode is characterized by a different pattern of coherence between cortical regions. This observation suggests that changing patterns of cortical coherence are a hallmark of normal thalamocortical dynamics. In a preliminary study, we test this idea by analyzing the EEG of a patient with chronic brain injury, who has a marked improvement in behavior and frontal brain metabolism in response to zolpidem. The analysis shows that following zolpidem administration, changing patterns of coherence are identified between the frontal lobes and between frontal and distant brain regions. These observations support the role of the central thalamus in the organization of patterns of cortical interactions and suggest how indexes of thalamocortical dynamics can be extracted from the EEG.

  1. Radioiodine therapy in benign thyroid diseases

    DEFF Research Database (Denmark)

    Bonnema, Steen Joop; Hegedüs, Laszlo

    2012-01-01

    from (131)I therapy. The individual radiosensitivity, still poorly defined and impossible to quantify, may be a major determinant of the outcome from (131)I therapy. Above all, the impact of (131)I therapy relies on the iodine-concentrating ability of the thyroid gland. The thyroid (131)I uptake (or......Radioiodine ((131)I) therapy of benign thyroid diseases was introduced 70 yr ago, and the patients treated since then are probably numbered in the millions. Fifty to 90% of hyperthyroid patients are cured within 1 yr after (131)I therapy. With longer follow-up, permanent hypothyroidism seems...... of an exact thyroid dose is error-prone due to imprecise measurement of the (131)I biokinetics, and the importance of internal dosimetric factors, such as the thyroid follicle size, is probably underestimated. Besides these obstacles, several potential confounders interfere with the efficacy of (131)I therapy...

  2. [Endoscopic surgery for benign esophageal diseases].

    Science.gov (United States)

    Ozawa, Soji

    2006-07-01

    Gastroesophageal reflux disease (GERD) and esophageal achalasia are common benign esophageal diseases. Today minimally invasive surgery is recommended to treat these diseases. Surgical indications for GERD are failure of medical management, medical complications attributable to a large hiatal hernia, 'atypical' symptoms (asthma, hoarseness, cough, chest pain, aspiration), etc. according to the Society of American Gastrointestinal Endoscopic Surgeons (SAGES) guidelines. Laparoscopic Nissen fundoplication has emerged as the most widely accepted procedure for GERD patients with normal esophageal motility. Partial fundoplication (e.g., Toupet fundoplication) is also considered to decrease the possibility of postoperative dysphagia. Although pneumatic dilatation has been the first line treatment for esophageal achalasia, laparoscopic Heller myotomy and partial fundoplication (e.g., Dor fundoplication) to prevent reflux is preferred by most gastroenterologists and surgeons as the primary treatment modality. Laparoscopic surgery for GERD and esophageal achalasia are effective in most patients and safe in all patients. Finally, laparoscopic surgery should be performed only by skilled surgeons.

  3. A rare case of benign omentum teratoma

    Directory of Open Access Journals (Sweden)

    Sforza Marcos

    2012-01-01

    Full Text Available Introduction. Mature teratomas (benign cystic teratomas or dermoid cysts are among the most common ovarian tumours; however, teratomas of the omentum and mesentery are extremely rare. Teratoma in the intraperitoneal cavity is uncommon and atypical, and it is even more uncommon in adulthood. Case Outline. An 82-year-old female was admitted to our department with clinical signs of abdominal tumour. The ultrasound scan and preoperative laboratory tests were done. Explorative laparotomy revealed tumour with torsion on its pedicle at the greater omentum. After removal of the mass and the incision a tooth and hair were found, characteristics of teratoma. Conclusion. The excision was very effective and also definitive treatment for this case. The patient recovered well and was discharged 3 days later. The patient probably carried the tumour all her life asymptomatically until admission.

  4. Palladium-Catalyzed Environmentally Benign Acylation.

    Science.gov (United States)

    Suchand, Basuli; Satyanarayana, Gedu

    2016-08-05

    Recent trends in research have gained an orientation toward developing efficient strategies using innocuous reagents. The earlier reported transition-metal-catalyzed carbonylations involved either toxic carbon monoxide (CO) gas as carbonylating agent or functional-group-assisted ortho sp(2) C-H activation (i.e., ortho acylation) or carbonylation by activation of the carbonyl group (i.e., via the formation of enamines). Contradicting these methods, here we describe an environmentally benign process, [Pd]-catalyzed direct carbonylation starting from simple and commercially available iodo arenes and aldehydes, for the synthesis of a wide variety of ketones. Moreover, this method comprises direct coupling of iodoarenes with aldehydes without activation of the carbonyl and also without directing group assistance. Significantly, the strategy was successfully applied to the synthesis n-butylphthalide and pitofenone.

  5. The debate over robotics in benign gynecology.

    Science.gov (United States)

    Rardin, Charles R

    2014-05-01

    The debate over the role of the da Vinci surgical robotic platform in benign gynecology is raging with increasing fervor and, as product liability issues arise, greater financial stakes. Although the best currently available science suggests that, in the hands of experts, robotics offers little in surgical advantage over laparoscopy, at increased expense, the observed decrease in laparotomy for hysterectomy is almost certainly, at least in part, attributable to the availability of the robot. In this author's opinion, the issue is not whether the robot has any role but rather to define the role in an institutional environment that also supports the safe use of vaginal and laparoscopic approaches in an integrated minimally invasive surgery program. Programs engaging robotic surgery should have a clear and self-determined regulatory process and should resist pressures in place that may preferentially support robotics over other forms of minimally invasive surgery.

  6. Benign familial polycythaemia in a young male

    Directory of Open Access Journals (Sweden)

    Somanth Maitra

    2012-01-01

    Full Text Available Polycythaemia has been reported rarely as a familial condition. There is evidence to suggest transmission as a Mendelian dominant trait, but recessive inheritance has also been described. We present here a case of benign familial polycythaemia in a 25-year-old male with similar presentation in his family members. Our patient presented with reddish discolouration of eyes, early satiety , weight loss and itching at intervals for four years. An additional examination revealed red beefy tongue and Grade III clubbing. The importance of presenting this case lies in the fact that the prognosis appears to be good in these patients, but regular observation is necessary as Kiladjian and colleagues have mentioned that there is a risk of leukaemia, thrombosis and myelofibrosis in these patients later on, as the idiopathic erythrocytosis group contains a certain number of polycythaemia patients.

  7. Risk stratification for benign prostatic hyperplasia.

    Science.gov (United States)

    Zattoni, Fabio; Ficarra, Vincenzo; Novara, Giacomo

    2017-03-18

    Benign prostatic hyperplasia (BPH) represents an important public health problem in ageing men due to frequently associated lower urinary tract symptoms (LUTS), which may impair quality of life. BPH is also a progressive disease, mainly characterized by a worsening of LUTS over time, and in some patients by the occurrence of serious outcomes such as acute urinary retention and need for BPH-related surgery. The management of BPH and LUTS in men should move forward its focus on symptom control only. Indeed, the goals of therapy for BPH are not only to improve bothersome LUTS but also to identify those patients at risk of unfavourable outcomes in order to optimize their management and reduce complications. Risk stratification and tailored treatment should improve the reductions in both symptoms and the long-term consequences of BPH and BPH treatments. To do this, clinicians need to know possible factors that may support the develop of PBH and possible risks due to the BPH itself.

  8. Levodopa-Responsive Benign Tremulous Parkinsonism

    Directory of Open Access Journals (Sweden)

    Osamu Kano

    2013-08-01

    Full Text Available Background: Benign tremulous parkinsonism (BTP is a tremor dominant syndrome characterized by mild, levodopa-resistant parkinsonism with limited disability or progression. Case Presentation: A 56-year-old woman presented with a 2-year history of tremor. Neurological examination revealed right-hand rest tremor and slow finger tapping with decreased amplitude; however, we did not observe posture tremor, rigidity, bradykinesia, or posture disability. She was diagnosed with Parkinson's disease (PD and received levodopa/carbidopa, effectively treating her rest tremor. At the age of 61 years, reoccurrence of the rest tremor was successfully treated again with levodopa/carbidopa and selegiline. Approximately 11 years have passed since symptom onset and the patient shows no further disease progression. Conclusion: This case broadens the characterization of BTP to include levodopa-responsive PD.

  9. Climatic variations and benign paroxysmal positional vertigo

    Institute of Scientific and Technical Information of China (English)

    Basil M.N. Saeed; Alyaa Farouk Omari

    2016-01-01

    Benign paroxysmal positional vertigo (BPPV) is probably the most common diagnosis at vertigo clinics. Seasonal cycles of several human illnesses could be attributed variously to changes in atmospheric or weather conditions. In this retrospective study, patients with BPPV from January 2010 to December 2012 were studied, and their charts were reviewed. Statistical analysis revealed a statistically significant difference in patients' numbers among different months of the year. Also there is a significant statistical correlation between the numbers of patients with climatic variations especially the temperature. The present paper discusses the possible explanations for these results which confirms the seasonal variations in BPPV, together with a review of literature to view the possible associations with other disorders that causes such sea-sonality.

  10. Endoscopic management of benign biliary strictures.

    Science.gov (United States)

    Rustagi, Tarun; Jamidar, Priya A

    2015-01-01

    Benign biliary strictures are a common indication for endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic management has evolved over the last 2 decades as the current standard of care. The most common etiologies of strictures encountered are following surgery and those related to chronic pancreatitis. High-quality cross-sectional imaging provides a road map for endoscopic management. Currently, sequential placement of multiple plastic biliary stents represents the preferred approach. There is an increasing role for the treatment of these strictures using covered metal stents, but due to conflicting reports of efficacies as well as cost and complications, this approach should only be entertained following careful consideration. Optimal management of strictures is best achieved using a team approach with the surgeon and interventional radiologist playing an important role.

  11. Estimation of neural dynamics from MEG/EEG cortical current density maps: application to the reconstruction of large-scale cortical synchrony.

    Science.gov (United States)

    David, Olivier; Garnero, Line; Cosmelli, Diego; Varela, Francisco J

    2002-09-01

    There is a growing interest in elucidating the role of specific patterns of neural dynamics--such as transient synchronization between distant cell assemblies--in brain functions. Magnetoencephalography (MEG)/electroencephalography (EEG) recordings consist in the spatial integration of the activity from large and multiple remotely located populations of neurons. Massive diffusive effects and poor signal-to-noise ratio (SNR) preclude the proper estimation of indices related to cortical dynamics from nonaveraged MEG/EEG surface recordings. Source localization from MEG/EEG surface recordings with its excellent time resolution could contribute to a better understanding of the working brain. We propose a robust and original approach to the MEG/EEG distributed inverse problem to better estimate neural dynamics of cortical sources. For this, the surrogate data method is introduced in the MEG/EEG inverse problem framework. We apply this approach on nonaveraged data with poor SNR using the minimum norm estimator and find source localization results weakly sensitive to noise. Surrogates allow the reduction of the source space in order to reconstruct MEG/EEG data with reduced biases in both source localization and time-series dynamics. Monte Carlo simulations and results obtained from real MEG data indicate it is possible to estimate non invasively an important part of cortical source locations and dynamic and, therefore, to reveal brain functional networks.

  12. The Quantification of EEG Continuity by 24-hour Recordings in Intraventricular Hemorrhaging and Periventricular Leukomalacia : Its Prognostic Value in Comparison with Conventional EEG Recordings

    OpenAIRE

    Goto, Kazuya; Ogawa, Teruyuki; Sonoda, Hirotomi

    1995-01-01

    Investigation was made of the prognostic value of quantified 24-hour electroencephalogram (EEG) continuity by 24-hour EEG recordings early in the postnatal period as compared follow-up, conventional EEG recordings up to fullterm was evaluated for low-birth weight infants with intraventricular hemorrhage (IVH) and periventricular leukomalacia (PVL). Of twelve infants, 24-hour EEG recordings were performed on eight, and a total of 58 follow-up EEG recordings were obtained from the twelve. The 2...

  13. HOW BENIGN IS BPPV IN THE ELDERLY?

    Directory of Open Access Journals (Sweden)

    Rama Krishna

    2015-01-01

    Full Text Available Geriatric population in India is rapidly increasing. According to one estimate the number of persons above the age of 60 years is 76.6 million in India. India as the second most populous country in the world, with elderly people constituting 7.7% of total population. The morbidity in this age group is often due to increased incidence of falls. It is often preceded with spells of dizziness and often associated with vestibular disorders. Peripheral vestibular disorders often difficult to evaluate at the time of fall and only realized after the fall. Peripheral vestibular disorders like Benign Paroxysmal Positional Vertigo (BPPV, Vestibulopathy, Vestibular Neuritis are some of the disorders that affect geriatric population that affect the functional ability in ‘activities of daily living (ADL. BPPV has been frequently found to be more common with advancing age. One simple test to assess ADL (Activities of Daily Living is TUG test (Timed Up and Go. A score of 11.1 seconds or more on TUG test was correlated with 80% chance of a fall in the elderly. Hence a study is undertaken to evaluate peripheral vestibular disorders in elderly with special reference to BPPV along with their performance on TUG (Timed Up and Go test. Benign Paroxysmal Positional Vertigo (BPPV has been found to be most common vestibular disorder in the elderly . One out of four elderly with Peripheral vestibular disorder has a risk of ‘fall’. BPPV is the most common peripheral vestibular disorder leading to ‘risk of fall’ three times more among the elderly after 75years .

  14. Investigating Cooperative Behavior in Ecological Settings: An EEG Hyperscanning Study.

    Science.gov (United States)

    Toppi, Jlenia; Borghini, Gianluca; Petti, Manuela; He, Eric J; De Giusti, Vittorio; He, Bin; Astolfi, Laura; Babiloni, Fabio

    2016-01-01

    The coordinated interactions between individuals are fundamental for the success of the activities in some professional categories. We reported on brain-to-brain cooperative interactions between civil pilots during a simulated flight. We demonstrated for the first time how the combination of neuroelectrical hyperscanning and intersubject connectivity could provide indicators sensitive to the humans' degree of synchronization under a highly demanding task performed in an ecological environment. Our results showed how intersubject connectivity was able to i) characterize the degree of cooperation between pilots in different phases of the flight, and ii) to highlight the role of specific brain macro areas in cooperative behavior. During the most cooperative flight phases pilots showed, in fact, dense patterns of interbrain connectivity, mainly linking frontal and parietal brain areas. On the contrary, the amount of interbrain connections went close to zero in the non-cooperative phase. The reliability of the interbrain connectivity patterns was verified by means of a baseline condition represented by formal couples, i.e. pilots paired offline for the connectivity analysis but not simultaneously recorded during the flight. Interbrain density was, in fact, significantly higher in real couples with respect to formal couples in the cooperative flight phases. All the achieved results demonstrated how the description of brain networks at the basis of cooperation could effectively benefit from a hyperscanning approach. Interbrain connectivity was, in fact, more informative in the investigation of cooperative behavior with respect to established EEG signal processing methodologies applied at a single subject level.

  15. Investigating Cooperative Behavior in Ecological Settings: An EEG Hyperscanning Study.

    Directory of Open Access Journals (Sweden)

    Jlenia Toppi

    Full Text Available The coordinated interactions between individuals are fundamental for the success of the activities in some professional categories. We reported on brain-to-brain cooperative interactions between civil pilots during a simulated flight. We demonstrated for the first time how the combination of neuroelectrical hyperscanning and intersubject connectivity could provide indicators sensitive to the humans' degree of synchronization under a highly demanding task performed in an ecological environment. Our results showed how intersubject connectivity was able to i characterize the degree of cooperation between pilots in different phases of the flight, and ii to highlight the role of specific brain macro areas in cooperative behavior. During the most cooperative flight phases pilots showed, in fact, dense patterns of interbrain connectivity, mainly linking frontal and parietal brain areas. On the contrary, the amount of interbrain connections went close to zero in the non-cooperative phase. The reliability of the interbrain connectivity patterns was verified by means of a baseline condition represented by formal couples, i.e. pilots paired offline for the connectivity analysis but not simultaneously recorded during the flight. Interbrain density was, in fact, significantly higher in real couples with respect to formal couples in the cooperative flight phases. All the achieved results demonstrated how the description of brain networks at the basis of cooperation could effectively benefit from a hyperscanning approach. Interbrain connectivity was, in fact, more informative in the investigation of cooperative behavior with respect to established EEG signal processing methodologies applied at a single subject level.

  16. Investigating Cooperative Behavior in Ecological Settings: An EEG Hyperscanning Study

    Science.gov (United States)

    Petti, Manuela; He, Eric J.; De Giusti, Vittorio; He, Bin; Astolfi, Laura; Babiloni, Fabio

    2016-01-01

    The coordinated interactions between individuals are fundamental for the success of the activities in some professional categories. We reported on brain-to-brain cooperative interactions between civil pilots during a simulated flight. We demonstrated for the first time how the combination of neuroelectrical hyperscanning and intersubject connectivity could provide indicators sensitive to the humans’ degree of synchronization under a highly demanding task performed in an ecological environment. Our results showed how intersubject connectivity was able to i) characterize the degree of cooperation between pilots in different phases of the flight, and ii) to highlight the role of specific brain macro areas in cooperative behavior. During the most cooperative flight phases pilots showed, in fact, dense patterns of interbrain connectivity, mainly linking frontal and parietal brain areas. On the contrary, the amount of interbrain connections went close to zero in the non-cooperative phase. The reliability of the interbrain connectivity patterns was verified by means of a baseline condition represented by formal couples, i.e. pilots paired offline for the connectivity analysis but not simultaneously recorded during the flight. Interbrain density was, in fact, significantly higher in real couples with respect to formal couples in the cooperative flight phases. All the achieved results demonstrated how the description of brain networks at the basis of cooperation could effectively benefit from a hyperscanning approach. Interbrain connectivity was, in fact, more informative in the investigation of cooperative behavior with respect to established EEG signal processing methodologies applied at a single subject level. PMID:27124558

  17. Large mid-esophageal granular cell tumor: benign versus malignant

    Directory of Open Access Journals (Sweden)

    Prarthana Roselil Christopher

    2015-06-01

    Full Text Available Granular cell tumors are rare soft tissue neoplasms, among which only 2% are malignant, arising from nervous tissue. Here we present a case of a large esophageal granular cell tumor with benign histopathological features which metastasized to the liver, but showing on positron emission tomography-computerized tomography standardized uptake value suggestive of a benign lesion.

  18. Perfusion MR imaging for differentiation of benign and malignant meningiomas

    NARCIS (Netherlands)

    Zhang, Hao; Rodiger, Lars A.; Shen, Tianzhen; Miao, Jingtao; Oudkerk, Matthijs

    2008-01-01

    Introduction Our purpose was to determine whether perfusion MR imaging can be used to differentiate benign and malignant meningiomas on the basis of the differences in perfusion of tumor parenchyma and/or peritumoral edema. Methods A total of 33 patients with preoperative meningiomas (25 benign and

  19. Single benign metastasising leiomyoma of an inguinal lymph node.

    NARCIS (Netherlands)

    Laban, KG; Tobon-Morales, Roberto; Hodge, Janice; Schreuder, HWR

    2016-01-01

    Benign metastasising leiomyoma (BML) is a rare benign disease associated with uterine leiomyoma and history of uterine surgery. It most frequently occurs in premenopausal woman, with a pulmonary localisation, and consisting of multiple nodules. We present an uncommon case of a 69-year-old woman with

  20. Ultrasound Image Discrimination between Benign and Malignant Adnexal Masses Based on a Neural Network Approach.

    Science.gov (United States)

    Aramendía-Vidaurreta, Verónica; Cabeza, Rafael; Villanueva, Arantxa; Navallas, Javier; Alcázar, Juan Luis

    2016-03-01

    The discrimination between benign and malignant adnexal masses in ultrasound images represents one of the most challenging problems in gynecologic practice. In the study described here, a new method for automatic discrimination of adnexal masses based on a neural networks approach was tested. The proposed method first calculates seven different types of characteristics (local binary pattern, fractal dimension, entropy, invariant moments, gray level co-occurrence matrix, law texture energy and Gabor wavelet) from ultrasound images of the ovary, from which several features are extracted and collected together with the clinical patient age. The proposed technique was validated using 106 benign and 39 malignant images obtained from 145 patients, corresponding to its probability of appearance in general population. On evaluation of the classifier, an accuracy of 98.78%, sensitivity of 98.50%, specificity of 98.90% and area under the curve of 0.997 were calculated.

  1. Establishing the diagnosis of benign familial hematuria: the importance of examining the urine sediment of family members

    Energy Technology Data Exchange (ETDEWEB)

    Blumenthal, S.S.; Fritsche, C.; Lemann, J. Jr

    1988-04-15

    Patients with microscopic hematuria are generally referred for urologic investigation. The authors describe 30 patients with normal renal function referred to our clinic during the years 1970 through 1987 for evaluation of hematuria, usually microscopic, in whom prior urologic and radiological studies had failed to determine the cause of bleeding. Urinary sediment from the patients and first-degree relatives revealed hemoglobin and red blood cell casts; the inheritance pattern was consistent with autosomal dominant transmission. During follow-up for up to 18 years, renal function remained normal, thus confirming the diagnosis of benign familial hematuria. Immunoglobulin A nephropathy and Alport's syndrome were less common than benign familial hematuria and could be differentiated from it by history, physical examination, and routine laboratory testing. Since benign familial hematuria is a common disorder in adults with hematuria and normal renal function, urinary sediment from patients and family members should be examined before extensive urologic and radiological procedures are performed.

  2. Expression of urokinase plasminogen activator, its receptor and type-1 inhibitor in malignant and benign prostate tissue

    DEFF Research Database (Denmark)

    Usher, Pernille Autzen; Thomsen, Ole Frøkjær; Iversen, Peter

    2005-01-01

    RNAs was predominantly seen in cells identified as macrophages, which in most of the carcinomas (approximately 90%) were located in the interstitial tissue between the tumor cell islands, while in most of the benign hyperplasias they were located in the lumen of the glands and were in only a few cases (approximately 30......%) found in the interstitial tissue. uPAR immunoreactivity correlated with the mRNA expression and was, in addition, found in neutrophils. PAI-1 mRNA was detected in 13 of the 16 carcinomas and in 8 of the 9 benign hyperplasias, located in scattered fibroblast-like cells in both groups, in some vascular...... structures and in a few macrophages located in the interstitial tissue of both malignant and benign lesions. A similar expression pattern was found for PAI-1 immunoreactivity. In 8 of the 16 carcinomas, all 3 components were present, and in several areas colocalization was observed in stromal cells in close...

  3. The effectiveness of EEG-feedback on attention, impulsivity and EEG: a sham feedback controlled study.

    NARCIS (Netherlands)

    Logemann, H.N.; Lansbergen, M.M.; Os, T.W. Van; Bocker, K.B.; Kenemans, J.L.

    2010-01-01

    EEG-feedback, also called neurofeedback, is a training procedure aimed at altering brain activity, and is used as a treatment for disorders like Attention Deficit/Hyperactivity Disorder (ADHD). Studies have reported positive effects of neurofeedback on attention and other dependent variables. Howeve

  4. The effectiveness of EEG-feedback on attention, impulsivity and EEG : A sham feedback controlled study

    NARCIS (Netherlands)

    Logemann, H. N. Alexander; Lansbergen, Marieke M.; Van Os, Titus W. D. P.; Bocker, Koen B. E.; Kenemans, J. Leon

    2010-01-01

    EEG-feedback, also called neurofeedback, is a training procedure aimed at altering brain activity, and is used as a treatment for disorders like Attention Deficit/Hyperactivity Disorder (ADHD). Studies have reported positive effects of neurofeedback on attention and other dependent variables. Howeve

  5. EEG. Actual developments for biogas; EEG. Aktuelle Entwicklungen fuer den Biogasbereich

    Energy Technology Data Exchange (ETDEWEB)

    Keymer, Ulrich [Bayerische Landesanstalt fuer Landwirtschaft, Muenchen (Germany). Inst. fuer Laendliche Strukturentwicklung, Betriebswirtschaft und Agrarinformatik

    2011-07-01

    The EEG 2009 provided positive incentives. Nevertheless, adjustments were needed in order to make power generation from biogas even more efficient in the light of resource protection and environmental protection and taking into account the requirements of sustainability. The legislature has decided to revamp the compensation structure. From this perspective, the author of the contribution under consideration reports on these innovations and their impact.

  6. Clinical and EEG features of ischemic stroke patients with abnormal discharges

    Directory of Open Access Journals (Sweden)

    Jia-lei YANG

    2016-05-01

    generalized seizure.  Conclusions Infract site has an influence on the abnormal EEG pattern, and the unmatched location of ischemic region and abnormal EEG may be indicative for the seizure type of post-ischemic epilepsy. DOI: 10.3969/j.issn.1672-6731.2016.05.008

  7. Using EEG to Study Cognitive Development: Issues and Practices

    Science.gov (United States)

    Bell, Martha Ann; Cuevas, Kimberly

    2012-01-01

    Developmental research is enhanced by use of multiple methodologies for examining psychological processes. The electroencephalogram (EEG) is an efficient and relatively inexpensive method for the study of developmental changes in brain-behavior relations. In this review, we highlight some of the challenges for using EEG in cognitive development…

  8. EOG Artifacts Removal in EEG Measurements for Affective Interaction

    NARCIS (Netherlands)

    Qi, Wen

    2014-01-01

    A brain-computer interface (BCI) is a direct link between the brain and a computer. Multi-modal input with BCI forms a promising solution for creating rich gaming experience. Electroencephalography (EEG) measurement is the sole necessary component for a BCI system. EEG signals have the characteristi

  9. Convolutive ICA for Spatio-Temporal Analysis of EEG

    DEFF Research Database (Denmark)

    Dyrholm, Mads; Makeig, Scott; Hansen, Lars Kai

    2007-01-01

    in the convolutive model can be correctly detected using Bayesian model selection. We demonstrate a framework for deconvolving an EEG ICA subspace. Initial results suggest that in some cases convolutive mixing may be a more realistic model for EEG signals than the instantaneous ICA model....

  10. 21 CFR 882.1420 - Electroencephalogram (EEG) signal spectrum analyzer.

    Science.gov (United States)

    2010-04-01

    ....1420 Electroencephalogram (EEG) signal spectrum analyzer. (a) Identification. An electroencephalogram (EEG) signal spectrum analyzer is a device used to display the frequency content or power spectral... analyzer. 882.1420 Section 882.1420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH...

  11. An empirical EEG analysis in brain death diagnosis for adults.

    Science.gov (United States)

    Chen, Zhe; Cao, Jianting; Cao, Yang; Zhang, Yue; Gu, Fanji; Zhu, Guoxian; Hong, Zhen; Wang, Bin; Cichocki, Andrzej

    2008-09-01

    Electroencephalogram (EEG) is often used in the confirmatory test for brain death diagnosis in clinical practice. Because EEG recording and monitoring is relatively safe for the patients in deep coma, it is believed to be valuable for either reducing the risk of brain death diagnosis (while comparing other tests such as the apnea) or preventing mistaken diagnosis. The objective of this paper is to study several statistical methods for quantitative EEG analysis in order to help bedside or ambulatory monitoring or diagnosis. We apply signal processing and quantitative statistical analysis for the EEG recordings of 32 adult patients. For EEG signal processing, independent component analysis (ICA) was applied to separate the independent source components, followed by Fourier and time-frequency analysis. For quantitative EEG analysis, we apply several statistical complexity measures to the EEG signals and evaluate the differences between two groups of patients: the subjects in deep coma, and the subjects who were categorized as brain death. We report statistically significant differences of quantitative statistics with real-life EEG recordings in such a clinical study, and we also present interpretation and discussions on the preliminary experimental results.

  12. [EEG recordings during episodes of palinacousis and palinopsia].

    Science.gov (United States)

    Auzou, P; Parain, D; Ozsancak, C; Weber, J; Hannequin, D

    1997-11-01

    Palinopsia (visual perseveration) and palinacousis (auditory perseveration) are reported in a 51-year-old woman with a left temporo parietal astrocytoma. EEG showed a left temporal delta-focus with sharp waves. EEG was not modified during neither palinacousis nor palinopsia. The relationship between the two hallucinatory phenomena and epilepsy is discussed.

  13. Standardized computer-based organized reporting of EEG

    DEFF Research Database (Denmark)

    Beniczky, Sándor; Aurlien, Harald; Brøgger, Jan C

    2013-01-01

    The electroencephalography (EEG) signal has a high complexity, and the process of extracting clinically relevant features is achieved by visual analysis of the recordings. The interobserver agreement in EEG interpretation is only moderate. This is partly due to the method of reporting the finding...

  14. Effects of Fipronil on the EEG of Long Evans Rats

    Science.gov (United States)

    We have reported that the non-stimulus driven EEG is differentially altered by deltamethrin or permethrin (Lyke and Herr, Toxicologist, 114(S-1):265, 2010). In the current study, we examined the ability to detect changes in EEG activity produced by fipronil, a phenylpyrazole pest...

  15. EEG Signal Decomposition and Improved Spectral Analysis Using Wavelet Transform

    Science.gov (United States)

    2001-10-25

    research and medical applications. Wavelet transform (WT) is a new multi-resolution time-frequency analysis method. WT possesses localization feature both... wavelet transform , the EEG signals are successfully decomposed and denoised. In this paper we also use a ’quasi-detrending’ method for classification of EEG

  16. Assessing cortical network properties using TMS-EEG.

    Science.gov (United States)

    Rogasch, Nigel C; Fitzgerald, Paul B

    2013-07-01

    The past decade has seen significant developments in the concurrent use of transcranial magnetic stimulation (TMS) and electroencephalography (EEG) to directly assess cortical network properties such as excitability and connectivity in humans. New hardware solutions, improved EEG amplifier technology, and advanced data processing techniques have allowed substantial reduction of the TMS-induced artifact, which had previously rendered concurrent TMS-EEG impossible. Various physiological artifacts resulting from TMS have also been identified, and methods are being developed to either minimize or remove these sources of artifact. With these developments, TMS-EEG has unlocked regions of the cortex to researchers that were previously inaccessible to TMS. By recording the TMS-evoked response directly from the cortex, TMS-EEG provides information on the excitability, effective connectivity, and oscillatory tuning of a given cortical area, removing the need to infer such measurements from indirect measures. In the following review, we investigate the different online and offline methods for reducing artifacts in TMS-EEG recordings and the physiological information contained within the TMS-evoked cortical response. We then address the use of TMS-EEG to assess different cortical mechanisms such as cortical inhibition and neural plasticity, before briefly reviewing studies that have utilized TMS-EEG to explore cortical network properties at rest and during different functional brain states.

  17. Modeling temporal sequences of cognitive state changes based on a combination of EEG-engagement, EEG-workload, and heart rate metrics.

    Science.gov (United States)

    Stikic, Maja; Berka, Chris; Levendowski, Daniel J; Rubio, Roberto F; Tan, Veasna; Korszen, Stephanie; Barba, Douglas; Wurzer, David

    2014-01-01

    The objective of this study was to investigate the feasibility of physiological metrics such as ECG-derived heart rate and EEG-derived cognitive workload and engagement as potential predictors of performance on different training tasks. An unsupervised approach based on self-organizing neural network (NN) was utilized to model cognitive state changes over time. The feature vector comprised EEG-engagement, EEG-workload, and heart rate metrics, all self-normalized to account for individual differences. During the competitive training process, a linear topology was developed where the feature vectors similar to each other activated the same NN nodes. The NN model was trained and auto-validated on combat marksmanship training data from 51 participants that were required to make "deadly force decisions" in challenging combat scenarios. The trained NN model was cross validated using 10-fold cross-validation. It was also validated on a golf study in which additional 22 participants were asked to complete 10 sessions of 10 putts each. Temporal sequences of the activated nodes for both studies followed the same pattern of changes, demonstrating the generalization capabilities of the approach. Most node transition changes were local, but important events typically caused significant changes in the physiological metrics, as evidenced by larger state changes. This was investigated by calculating a transition score as the sum of subsequent state transitions between the activated NN nodes. Correlation analysis demonstrated statistically significant correlations between the transition scores and subjects' performances in both studies. This paper explored the hypothesis that temporal sequences of physiological changes comprise the discriminative patterns for performance prediction. These physiological markers could be utilized in future training improvement systems (e.g., through neurofeedback), and applied across a variety of training environments.

  18. Modeling temporal sequences of cognitive state changes based on a combination of EEG-engagement, EEG-workload, and heart rate metrics

    Directory of Open Access Journals (Sweden)

    Maja eStikic

    2014-11-01

    Full Text Available The objective of this study was to investigate the feasibility of physiological metrics such as ECG-derived heart rate and EEG-derived cognitive workload and engagement as potential predictors of performance on different training tasks. An unsupervised approach based on self-organizing neural network (NN was utilized to model cognitive state changes over time. The feature vector comprised EEG-engagement, EEG-workload, and heart rate metrics, all self-normalized to account for individual differences. During the competitive training process, a linear topology was developed where the feature vectors similar to each other activated the same NN nodes. The NN model was trained and auto-validated on combat marksmanship training data from 51 participants that were required to make deadly force decisions in challenging combat scenarios. The trained NN model was cross validated using 10-fold cross-validation. It was also validated on a golf study in which additional 22 participants were asked to complete 10 sessions of 10 putts each. Temporal sequences of the activated nodes for both studies followed the same pattern of changes, demonstrating the generalization capabilities of the approach. Most node transition changes were local, but important events typically caused significant changes in the physiological metrics, as evidenced by larger state changes. This was investigated by calculating a transition score as the sum of subsequent state transitions between the activated NN nodes. Correlation analysis demonstrated statistically significant correlations between the transition scores and subjects’ performances in both studies. This paper explored the hypothesis that temporal sequences of physiological changes comprise the discriminative patterns for performance prediction. These physiological markers could be utilized in future training improvement systems (e.g., through neurofeedback, and applied across a variety of training environments.

  19. Relationships between hippocampal activity and breathing patterns

    DEFF Research Database (Denmark)

    Harper, R M; Poe, G R; Rector, D M;

    1998-01-01

    Single cell discharge, EEG activity, and optical changes accompanying alterations in breathing patterns, as well as the knowledge that respiratory musculature is heavily involved in movement and other behavioral acts, implicate hippocampal regions in some aspects of breathing control. The control...

  20. Use of amplitude integrated electroencephalography (aEEG) in patients with inborn errors of metabolism - a new tool for the metabolic geneticist.

    Science.gov (United States)

    Theda, Christiane

    2010-01-01

    Patients with metabolic disorders often, especially as newborns, present with encephalopathy and seizures, frequently requiring intensive care during metabolic crises. Cerebral function monitoring using amplitude integrated electroencephalography (aEEG) can be utilized to supplement clinical assessment and other monitoring already in use in the intensive care setting. In this technique, a one or two-channel EEG tracing is obtained, processed, compressed and displayed. Use of aEEG is well established in evaluation and treatment of newborns with hypoxic ischemic encephalopathy. The basis of aEEG interpretation is the recognition of patterns which have been defined for different degrees of encephalopathy. Seizures are identified on the compressed tracing in combination with analysis of the corresponding raw EEG tracing. This review discusses the experience, although limited at this time, with use of aEEG in infants with inborn errors of metabolism. Through an international collaborative, the International Registry for Cerebral Function Monitoring in Patients with Genetics Disorders and Brain Malformations, aEEG tracings of patients with inborn errors of metabolism were collected. The features of 25 traces are included in this review. This collection includes patients with hyperammonemia (HA, n=4), disorders of energy metabolism (DEM, n=9), disorders of amino and organic acid metabolism (DAOAM, n=7), and peroxisomal disorders (PD, n=5). Fifteen of 25 patients demonstrated encephalopathic changes, including patients with HA, DEM and DAOAM, but not PD. In 15 of 25 patients seizure potentials were identified. In HA, DEM, and DAOAM both encephalopathy and seizures may coincide, while in peroxisomal disorders seizures were seen without background patterns indicating encephalopathy, likely due to neuronal migration defects as the underlying cause. The current experience with the use of aEEG in these patients, while limited, indicates that cerebral function monitoring

  1. [Cytogenetic aberrations in histologically benign infiltratively growing sphenoid wing meningiomas].

    Science.gov (United States)

    Korshunov, A G; Cherekaev, V A; Bekiashev, A Kh; Sycheva, R V

    2007-01-01

    Meningiomas of the sphenoid wing (SW) frequently show an invasive pattern of growth and cause destruction of the adjacent structures. As a result, the rate of recurrent SW meningiomas is as high as 30%. Cytogenetic investigations showed no aberrations specific to invasively growing meningiomas. During this study, the authors evaluated 10 invasive and 5 non-invasive SW meningiomas via comparative genome hybridization (CGH) (matrix CGH), by using the gene chips of GenoSensor Array micromatrixes. The mean number of aberrations in the tumor cells was much greater in case of invasive meningiomas (67.4 versus 40.5 in case of non-invasive SW meningiomas. Furthermore, in invasive SW meningiomas, there were frequently losses in loci 1p, 6q, and 14q and gains in loci 15q and 10, which had been predetermined as molecular markers of stepwise progression of meningioma. Thus, the presence of a complex cytogenetic profile and progression-associated chromosome aberrations in benign SW meningiomas is linked with the increase of their invasive potential. Due to the fact that there are no well-defined adjuvant therapy regimens for recurring meningiomas at present, the revealed genomic aberrations may become potential targets for searching for drugs and a therapeutic intervention in future.

  2. The default mode network and EEG regional spectral power: a simultaneous fMRI-EEG study.

    Science.gov (United States)

    Neuner, Irene; Arrubla, Jorge; Werner, Cornelius J; Hitz, Konrad; Boers, Frank; Kawohl, Wolfram; Shah, N Jon

    2014-01-01

    Electroencephalography (EEG) frequencies have been linked to specific functions as an "electrophysiological signature" of a function. A combination of oscillatory rhythms has also been described for specific functions, with or without predominance of one specific frequency-band. In a simultaneous fMRI-EEG study at 3 T we studied the relationship between the default mode network (DMN) and the power of EEG frequency bands. As a methodological approach, we applied Multivariate Exploratory Linear Optimized Decomposition into Independent Components (MELODIC) and dual regression analysis for fMRI resting state data. EEG power for the alpha, beta, delta and theta-bands were extracted from the structures forming the DMN in a region-of-interest approach by applying Low Resolution Electromagnetic Tomography (LORETA). A strong link between the spontaneous BOLD response of the left parahippocampal gyrus and the delta-band extracted from the anterior cingulate cortex was found. A positive correlation between the beta-1 frequency power extracted from the posterior cingulate cortex (PCC) and the spontaneous BOLD response of the right supplementary motor cortex was also established. The beta-2 frequency power extracted from the PCC and the precuneus showed a positive correlation with the BOLD response of the right frontal cortex. Our results support the notion of beta-band activity governing the "status quo" in cognitive and motor setup. The highly significant correlation found between the delta power within the DMN and the parahippocampal gyrus is in line with the association of delta frequencies with memory processes. We assumed "ongoing activity" during "resting state" in bringing events from the past to the mind, in which the parahippocampal gyrus is a relevant structure. Our data demonstrate that spontaneous BOLD fluctuations within the DMN are associated with different EEG-bands and strengthen the conclusion that this network is characterized by a specific

  3. The default mode network and EEG regional spectral power: a simultaneous fMRI-EEG study.

    Directory of Open Access Journals (Sweden)

    Irene Neuner

    Full Text Available Electroencephalography (EEG frequencies have been linked to specific functions as an "electrophysiological signature" of a function. A combination of oscillatory rhythms has also been described for specific functions, with or without predominance of one specific frequency-band. In a simultaneous fMRI-EEG study at 3 T we studied the relationship between the default mode network (DMN and the power of EEG frequency bands. As a methodological approach, we applied Multivariate Exploratory Linear Optimized Decomposition into Independent Components (MELODIC and dual regression analysis for fMRI resting state data. EEG power for the alpha, beta, delta and theta-bands were extracted from the structures forming the DMN in a region-of-interest approach by applying Low Resolution Electromagnetic Tomography (LORETA. A strong link between the spontaneous BOLD response of the left parahippocampal gyrus and the delta-band extracted from the anterior cingulate cortex was found. A positive correlation between the beta-1 frequency power extracted from the posterior cingulate cortex (PCC and the spontaneous BOLD response of the right supplementary motor cortex was also established. The beta-2 frequency power extracted from the PCC and the precuneus showed a positive correlation with the BOLD response of the right frontal cortex. Our results support the notion of beta-band activity governing the "status quo" in cognitive and motor setup. The highly significant correlation found between the delta power within the DMN and the parahippocampal gyrus is in line with the association of delta frequencies with memory processes. We assumed "ongoing activity" during "resting state" in bringing events from the past to the mind, in which the parahippocampal gyrus is a relevant structure. Our data demonstrate that spontaneous BOLD fluctuations within the DMN are associated with different EEG-bands and strengthen the conclusion that this network is characterized by a specific

  4. Filter transient response to EEG waveforms.

    Science.gov (United States)

    Shirakawa, S; Smith, J R; Azumi, K

    1987-01-01

    The response of two types of linear filters to sinusoidal bursts was calculated to demonstrate how filters can distort EEG waveforms. Results show that the wider the filter bandwidth the less is the distortion, and for a given bandwidth, the higher the filter order the greater the distortion. The response of a linear phase filter was also calculated to demonstrate that this type of filter can also cause waveform distortion, although it is normally less than that caused by Butterworth, Tchebychev and elliptic filters.

  5. Resting state EEG oscillatory power differences in ADHD college students and their peers

    Directory of Open Access Journals (Sweden)

    Woltering Steven

    2012-12-01

    Full Text Available Abstract Background Among the most robust neural abnormalities differentiating individuals with Attention-Deficit/Hyperactivity Disorder (ADHD from typically developing controls are elevated levels of slow oscillatory activity (e.g., theta and reduced fast oscillatory activity (e.g., alpha and beta during resting-state electroencephalography (EEG. However, studies of resting state EEG in adults with ADHD are scarce and yield inconsistent findings. Methods EEG profiles, recorded during a resting-state with eyes-open and eyes-closed conditions, were compared for college students with ADHD (n = 18 and a nonclinical comparison group (n = 17. Results The ADHD group showed decreased power for fast frequencies, especially alpha. This group also showed increased power in the slow frequency bands, however, these effects were strongest using relative power computations. Furthermore, the theta/beta ratio measure was reliably higher for the ADHD group. All effects were more pronounced for the eyes-closed compared to the eyes-open condition. Measures of intra-individual variability suggested that brains of the ADHD group were less variable than those of controls. Conclusions The findings of this pilot study reveal that college students with ADHD show a distinct neural pattern during resting state, suggesting that oscillatory power, especially alpha, is a useful index for reflecting differences in neural communication of ADHD in early adulthood.

  6. Face, eye, and body selective responses in fusiform gyrus and adjacent cortex: an intracranial EEG study.

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    Andrew D Engell

    2014-08-01

    Full Text Available Functional MRI (fMRI studies have investigated the degree to which processing of whole faces, face-parts, and bodies are differentially localized within the fusiform gyrus and adjacent ventral occipitotemporal cortex. While some studies have emphasized the spatial differentiation of processing into discrete areas, others have emphasized the overlap of processing and the importance of distributed patterns of activity. Intracranial EEG (iEEG recorded from subdural electrodes provides excellent temporal and spatial resolution of local neural activity, and thus provides an alternative method to fMRI for studying differences and commonalities in face and body processing. In this study we recorded iEEG from 12 patients while they viewed images of novel faces, isolated eyes, headless bodies, and flowers. ERP analysis identified 69 occipitotemporal sites at which there was a face-, eye-, or body-selective response when contrasted to flowers. However, when comparing faces, eyes, and bodies to each other at these sites, we identified only 3 face-specific, 13 eye-specific, and 1 body-specific electrodes. Thus, at the majority of sites, faces, eyes, and bodies evoked similar responses. However, we identified ten locations at which the amplitude of the responses spatially varied across adjacent electrodes, indicating that the configuration of current sources and sinks were different for faces, eyes, and bodies. Our results also demonstrate that eye-sensitive regions are more abundant and more purely selective than face- or body-sensitive regions, particularly in lateral occipitotemporal cortex.

  7. Face, eye, and body selective responses in fusiform gyrus and adjacent cortex: an intracranial EEG study.

    Science.gov (United States)

    Engell, Andrew D; McCarthy, Gregory

    2014-01-01

    Functional MRI (fMRI) studies have investigated the degree to which processing of whole faces, face-parts, and bodies are differentially localized within the fusiform gyrus and adjacent ventral occipitotemporal cortex. While some studies have emphasized the spatial differentiation of processing into discrete areas, others have emphasized the overlap of processing and the importance of distributed patterns of activity. Intracranial EEG (iEEG) recorded from subdural electrodes provides excellent temporal and spatial resolution of local neural activity, and thus provides an alternative method to fMRI for studying differences and commonalities in face and body processing. In this study we recorded iEEG from 12 patients while they viewed images of novel faces, isolated eyes, headless bodies, and flowers. Event-related potential analysis identified 69 occipitotemporal sites at which there was a face-, eye-, or body-selective response when contrasted to flowers. However, when comparing faces, eyes, and bodies to each other at these sites, we identified only 3 face-specific, 13 eye-specific, and 1 body-specific electrodes. Thus, at the majority of sites, faces, eyes, and bodies evoked similar responses. However, we identified ten locations at which the amplitude of the responses spatially varied across adjacent electrodes, indicating that the configuration of current sources and sinks were different for faces, eyes, and bodies. Our results also demonstrate that eye-sensitive regions are more abundant and more purely selective than face- or body-sensitive regions, particularly in lateral occipitotemporal cortex.

  8. Hybrid EEG-fNIRS Asynchronous Brain-Computer Interface for Multiple Motor Tasks.

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    Alessio Paolo Buccino

    Full Text Available Non-invasive Brain-Computer Interfaces (BCI have demonstrated great promise for neuroprosthetics and assistive devices. Here we aim to investigate methods to combine Electroencephalography (EEG and functional Near-Infrared Spectroscopy (fNIRS in an asynchronous Sensory Motor rhythm (SMR-based BCI. We attempted to classify 4 different executed movements, namely, Right-Arm-Left-Arm-Right-Hand-Left-Hand tasks. Previous studies demonstrated the benefit of EEG-fNIRS combination. However, since normally fNIRS hemodynamic response shows a long delay, we investigated new features, involving slope indicators, in order to immediately detect changes in the signals. Moreover, Common Spatial Patterns (CSPs have been applied to both EEG and fNIRS signals. 15 healthy subjects took part in the experiments and since 25 trials per class were available, CSPs have been regularized with information from the entire population of participants and optimized using genetic algorithms. The different features have been compared in terms of performance and the dynamic accuracy over trials shows that the introduced methods diminish the fNIRS delay in the detection of changes.

  9. Brain activity underlying visual perception and attention as inferred from TMS-EEG: a review.

    Science.gov (United States)

    Taylor, Paul Christopher John; Thut, Gregor

    2012-04-01

    Probing brain functions by brain stimulation while simultaneously recording brain activity allows addressing major issues in cognitive neuroscience. We review recent studies where electroencephalography (EEG) has been combined with transcranial magnetic stimulation (TMS) in order to investigate possible neuronal substrates of visual perception and attention. TMS-EEG has been used to study both pre-stimulus brain activity patterns that affect upcoming perception, and also the stimulus-evoked and task-related inter-regional interactions within the extended visual-attentional network from which attention and perception emerge. Local processes in visual areas have been probed by directly stimulating occipital cortex while monitoring EEG activity and perception. Interactions within the attention network have been probed by concurrently stimulating frontal or parietal areas. The use of tasks manipulating implicit and explicit memory has revealed in addition a role for attentional processes in memory. Taken together, these studies helped to reveal that visual selection relies on spontaneous intrinsic activity in visual cortex prior to the incoming stimulus, their control by attention, and post-stimulus processes incorporating a re-entrant bias from frontal and parietal areas that depends on the task.

  10. Detection of mental imagery and attempted movements in patients with disorders of consciousness using EEG.

    Science.gov (United States)

    Horki, Petar; Bauernfeind, Günther; Klobassa, Daniela S; Pokorny, Christoph; Pichler, Gerald; Schippinger, Walter; Müller-Putz, Gernot R

    2014-01-01

    Further development of an EEG based communication device for patients with disorders of consciousness (DoC) could benefit from addressing the following gaps in knowledge-first, an evaluation of different types of motor imagery; second, an evaluation of passive feet movement as a mean of an initial classifier setup; and third, rapid delivery of biased feedback. To that end we investigated whether complex and/or familiar mental imagery, passive, and attempted feet movement can be reliably detected in patients with DoC using EEG recordings, aiming to provide them with a means of communication. Six patients in a minimally conscious state (MCS) took part in this study. The patients were verbally instructed to perform different mental imagery tasks (sport, navigation), as well as attempted feet movements, to induce distinctive event-related (de)synchronization (ERD/S) patterns in the EEG. Offline classification accuracies above chance level were reached in all three tasks (i.e., attempted feet, sport, and navigation), with motor tasks yielding significant (p art in similar studies, to which we contributed by comparing different types of mental tasks, notably complex motor imagery and attempted feet movements, within patients. Furthermore, we explored new venues, such as an evaluation of passive feet movement as a mean of an initial classifier setup, and rapid delivery of biased feedback.

  11. Optimizing rTMS treatment of a balance disorder with EEG neural synchrony and functional connectivity.

    Science.gov (United States)

    Guofa Shou; Han Yuan; Urbano, Diamond; Yoon-Hee Cha; Lei Ding

    2016-08-01

    Repetitive transcranial magnetic stimulation (rTMS) has been increasingly used for its potential treatment effects across diverse mental disorders. However, the treatment effect is elusive and the rate of positive responders is not high, which make it in great demand of optimizing rTMS protocols to improve the treatment effects and the rate. In this regard, neural activity guided optimization has indicated great potential in several neuroimaging studies. In this paper, we present our ongoing work on optimizing rTMS treatment of a balance disorder, i.e., Mal de Debarquement syndrome (MdDS), by investigating treatment-related EEG neural synchrony and functional connectivity changes. Motivated by our previous pilot study of rTMS on MdDS, we firstly applied a bilateral dorsolateral prefrontal cortex (DLPFC) rTMS protocol to evaluate its efficacy and the treatment-related neural responses via an independent component analysis (ICA)-based framework. Thereafter, guided by identified EEG neural synchrony and functional connectivity patterns, we proposed three potential stimulation targets covering posterior nodes of the default mode network (DMN), and implemented a new rTMS protocol by stimulating the target with the great symptoms relief. The preliminary clinical response data has indicated that the new rTMS protocol significantly increase the rate of positive responders and the degrees of the improvement. The present study demonstrates that it is promising to integrate EEG neural synchrony and functional connectivity into the optimization of rTMS protocols for different mental disorders.

  12. Disentangling Tinnitus Distress and Tinnitus Presence by Means of EEG Power Analysis

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    Martin Meyer

    2014-01-01

    Full Text Available The present study investigated 24 individuals suffering from chronic tinnitus (TI and 24 nonaffected controls (CO. We recorded resting-state EEG and collected psychometric data to obtain information about how chronic tinnitus experience affects the cognitive and emotional state of TI. The study was meant to disentangle TI with high distress from those who suffer less from persistent tinnitus based on both neurophysiological and behavioral data. A principal component analysis of psychometric data uncovers two distinct independent dimensions characterizing the individual tinnitus experience. These independent states are distress and presence, the latter is described as the perceived intensity of sound experience that increases with tinnitus duration devoid of any considerable emotional burden. Neuroplastic changes correlate with the two independent components. TI with high distress display increased EEG activity in the oscillatory range around 25 Hz (upper β-band that agglomerates over frontal recording sites. TI with high presence show enhanced EEG signal strength in the δ-, α-, and lower γ-bands (30–40 Hz over bilateral temporal and left perisylvian electrodes. Based on these differential patterns we suggest that the two dimensions, namely, distress and presence, should be considered as independent dimensions of chronic subjective tinnitus.

  13. Turner syndrome: review of clinical, neuropsychiatric, and EEG status: an experience of tertiary center.

    Science.gov (United States)

    Saad, Khaled; Abdelrahman, Ahmed A; Abdel-Raheem, Yasser F; Othman, Essam R; Badry, Reda; Othman, Hisham A K; Sobhy, Karema M

    2014-03-01

    We reviewed the clinical, neuropsychiatric, and EEG status of 53 turner syndrome (TS) females, aged 3-16 years, in Assiut university hospitals, Upper Egypt. The diagnosis and care of patients with TS in Egypt is still in the developing stage. Hence this study was undertaken to review the details of patients with TS with respect to the pattern of cognitive, psychiatric, and motor dysfunction. We aimed to provide a comprehensive data about the experience of our center comparable to previous studies, which have been published in this field. This will contribute to a better definition of the neuropsychiatric features that may be specific to TS that allows early and better detection and management of these cases. We found FSIQ and verbal IQ that seem to be at a nearly normal level and a decreased performance IQ. ADHD and autistic symptoms were found in 20.70 and 3.77 % of our cohort, respectively. The motor performance in TS was disturbed, with some neurological deficits present in 17 % (reduced muscle tone and reduced muscle power). In addition, females with TS in our study exhibit social and emotional problems, including anxiety (5.66 %) and depression (11.30 %). The EEG results revealed abnormalities in seven patients (13.20 %). One patient presenting with generalized tonic-clonic seizures showed generalized epileptiform activity, and six patients presenting with intellectual disabilities showed abnormal EEG background activity.

  14. Design of an EEG Preamplifier for Brain-Computer Interface

    Institute of Scientific and Technical Information of China (English)

    Xian-Jie Pu; Tie-Jun Liu; De-Zhong Yao

    2009-01-01

    As a non-invasive neurophysiological index for brain-computer interface (BCI),electro-encephalogram (EEG) attracts much attention at present.In order to have a portable BCI,a simple and efficient pre-amplifier is crucial in practice.In this work,a preamplifier based on the characteristics of EEG signals is designed,which consists of a highly symmetrical input stage,low-pass filter,50 Hz notch filter and a post amplifier.A prototype of this EEG module is fabricated and EEG data are obtained through an actual experiment.The results demonstrate that the EEG preamplifier will be a promising unit for BCI in the future.

  15. Quantitative EEG evaluation in patients with acute encephalopathy

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    Aline Souza Marques da Silva Braga

    2013-12-01

    Full Text Available Objective To investigate the use of quantitative EEG (qEEG in patients with acute encephalopathies (AEs and EEG background abnormalities. Method Patients were divided into favorable outcome (group A, 43 patients and an unfavorable outcome (group B, 5 patients. EEGLAB software was used for the qEEG analysis. A graphic of the spectral power from all channels was generated for each participant. Statistical comparisons between the groups were performed. Results In group A, spectral analysis revealed spectral peaks (theta and alpha frequency bands in 84% (38/45 of the patients. In group B, a spectral peak in the delta frequency range was detected in one patient. The remainder of the patients in both groups did not present spectral peaks. Statistical analysis showed lower frequencies recorded from the posterior electrodes in group B patients. Conclusion qEEG may be useful in the evaluations of patients with AEs by assisting with the prognostic determination.

  16. EEG Suppression Associated with Apneic Episodes in a Neonate

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    Evonne Low

    2012-01-01

    Full Text Available We describe the EEG findings from an ex-preterm neonate at term equivalent age who presented with intermittent but prolonged apneic episodes which were presumed to be seizures. A total of 8 apneic episodes were captured (duration 23–376 seconds during EEG monitoring. The baseline EEG activity was appropriate for corrected gestational age and no electrographic seizure activity was recorded. The average baseline heart rate was 168 beats per minute (bpm and the baseline oxygen saturation level was in the mid-nineties. Periods of complete EEG suppression lasting 68 and 179 seconds, respectively, were recorded during 2 of these 8 apneic episodes. Both episodes were accompanied by bradycardia less than 70 bpm and oxygen saturation levels of less than 20%. Short but severe episodes of apnea can cause complete EEG suppression in the neonate.

  17. EEG data compression to monitor DoA in telemedicine.

    Science.gov (United States)

    Palendeng, Mario E; Zhang, Qing; Pang, Chaoyi; Li, Yan

    2012-01-01

    Data compression techniques have been widely used to process and transmit huge amount of EEG data in real-time and remote EEG signal processing systems. In this paper we propose a lossy compression technique, F-shift, to compress EEG signals for remote depth of Anaesthesia (DoA) monitoring. Compared with traditional wavelet compression techniques, our method not only preserves valuable clinical information with high compression ratios, but also reduces high frequency noises in EEG signals. Moreover, our method has negligible compression overheads (less than 0.1 seconds), which can greatly benefit real-time EEG signal monitoring systems. Our extensive experiments demonstrate the efficiency and effectiveness of the proposed compression method.

  18. [Qualitative and quantitative EEG-findings in schizophrenia (author's transl)].

    Science.gov (United States)

    Itil, T M

    1978-03-01

    The results of the qualitative but particularly the quantitative EEG-studies indicate that 1. The EEG of adult schizophrenics is characterized by an appearance of excessive fast activity along with some slow waves and the lack of alpha-activity. 2. Excessive fast activity and lack of alpha-waves have also been found in the EEGs of psychotic children and most interestingly in children whose parents (particularly the mother) are schizophrenic (high risk children). 3. Based on the studies during sleep and investigations with neuroleptics, it was established that the origin of the excess fast activity in schizophrenia cannot be the muscle potential. Particularly the excess fast activity in high risk children for schizophrenia goes against the muscle potential hypothesis. 4. The quantitative EEG changes seen in schizophrenia show similarity to those seen after hallucinogenic compounds particularly after anticholinergic hallucinogenics. 5. All neuroleptics (major tranquilizers) produce quantitative EEG alterations which are almost diametrically opposite to those seen in schizoprenia.

  19. Recognition of Epileptic EEG Using Probabilistic Neural Network

    CERN Document Server

    Bao, Forrest Sheng; Lie, Donald Yu-Chun

    2008-01-01

    Epilepsy is one of the most common neurological disorders that greatly impair patients' daily lives. A classifier for automated epileptic EEG detection and patient monitoring can be very important for epilepsy diagnosis and patients' quality of life, especially for rural areas and developing countries where medical resources are limited. This paper describes our development of an accurate and fast EEG classifier that can differentiate the EEG data of healthy people from that of epileptic patients, and also detect patients' status (i.e., interictal vs. ictal). We deployed Probabilistic Neural Network (PNN) and fed it with 38 features extracted from the EEG data. The resulting PNN EEG classifier achieves an impressive accuracy greater than 96 as indicated by cross-validation. This prototype classifier is therefore suitable for automated epilepsy detection/diagnosis and seizure monitoring. It may even facilitate seizure prediction.

  20. Enhanced dynamic complexity in the human EEG during creative thinking.

    Science.gov (United States)

    Mölle, M; Marshall, L; Lutzenberger, W; Pietrowsky, R; Fehm, H L; Born, J

    1996-04-12

    This study shows that divergent thinking, considered the general process underlying creative production, can be distinguished from convergent, analytical thought based on the dimensional complexity of ongoing electroencephalographic (EEG) activity. EEG complexity over the central and posterior cortex was higher while subjects solved tasks of divergent than convergent thinking, and also higher than during mental relaxation. Over the frontal cortex, EEG complexity was comparable during divergent thinking and mental relaxation, but reduced during convergent thinking. Results indicate that the basic process underlying the generation of novel ideas expresses itself in a strong increase in the EEG's complexity, reflecting higher degrees of freedom in the competitive interactions among cortical neuron assemblies. Frontocortical EEG complexity being comparable with that during mental relaxation, speaks for a loosened attentional control during creative thinking.

  1. Detection of mental imagery and attempted movements in patients with disorders of consciousness using EEG

    Directory of Open Access Journals (Sweden)

    Petar eHorki

    2014-12-01

    Full Text Available Further development of an EEG based communication device for patients with disorders of consciousness (DoC could benefit from addressing the following gaps in knowledge – first, an evaluation of different types of motor imagery; second, an evaluation of passive feet movement as a mean of an initial classifier setup; and third, rapid delivery of biased feedback. To that end we investigated whether complex and / or familiar mental imagery, passive, and attempted feet movement can be reliably detected in patients with DoC using EEG recordings, aiming to provide them with a means of communication. Six patients in a minimally conscious state (MCS took part in this study. The patients were verbally instructed to perform different mental imagery tasks (sport, navigation, as well as attempted feet movements, to induce distinctive event-related (desynchronization (ERD/S patterns in the EEG. Offline classification accuracies above chance level were reached in all three tasks (i.e. attempted feet, sport, and navigation, with motor tasks yielding significant (p<0.05 results more often than navigation (sport: 10 out of 18 sessions; attempted feet: 7 out of 14 sessions; navigation: 4 out of 12 sessions. The passive feet movements, evaluated in one patient, yielded mixed results: whereas time-frequency analysis revealed task-related EEG changes over neurophysiological plausible cortical areas, the classification results were not significant enough (p<0.05 to setup an initial classifier for the detection of attempted movements. Concluding, the results presented in this study are consistent with the current state of the art in similar studies, to which we contributed by comparing different types of mental tasks, notably complex motor imagery and attempted feet movements, within patients. Furthermore, we explored new venues, such as an evaluation of passive feet movement as a mean of an initial classifier setup, and rapid delivery of biased feedback.

  2. The time-course of EEG Alpha Power Changes in Creative Ideation

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    Daniela eSchwab

    2014-05-01

    Full Text Available Increases in EEG alpha power during creative ideation are among the most consistent findings in the neuroscientific study of creativity, but existing studies did not focus on time-related changes of EEG alpha activity patterns during the process of creative ideation so far. Since several cognitive processes are involved in the generation of creative ideas, different EEG correlates may result as a function of time. In this study we addressed this crucial point. Forty-five participants worked on the Alternative Uses Task while the EEG was recorded and changes in task-related power (relative to rest in the upper-frequency band (10-12 Hz for three isochronous time intervals of the idea generation period were determined. Alpha power changes during idea generation followed a characteristic time course: We found a general increase of alpha power at the beginning of idea generation that was followed by a decrease and finally by a re-increase of alpha prior to responding that was most pronounced at parietal and temporal sites of the right hemisphere. Additionally, the production of more original ideas was accompanied by increasing hemispheric asymmetry (more alpha in the right than left hemisphere with increasing duration of the idea generation period. The observed time course of brain activity may reflect the progression of different but well-known stages in the idea generation process: That is the initial retrieval of common and old ideas followed by the actual generation of novel and more creative ideas by overcoming typical responses through processes of mental simulation and imagination.

  3. Abnormal Parietal Brain Function in ADHD: Replication and Extension of Previous EEG Beta Asymmetry Findings

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    T. Sigi eHale

    2014-07-01

    Full Text Available Background: Abundant work indicates ADHD abnormal posterior brain structure and function, including abnormal structural and functional asymmetries and reduced corpus callosum size. However, this literature has attracted considerably less research interest than fronto-striatal findings. Objective: To help address this imbalance, the current study replicates and extends our previous work showing abnormal parietal brain function in ADHD adults during the Conner’s continuous performance test (CPT. Method: Our previous study found that ADHD adults had increased rightward EEG beta (16-21 Hz asymmetry in inferior parietal brain regions during the CPT (p=.00001, and that this metric exhibited a lack of normal correlation (i.e., observed in controls with beta asymmetry at temporal-parietal regions. We re-tested these effects in a new ADHD sample, and with both new and old samples combined. We additionally examined: a EEG asymmetry in multiple frequency bands, b unilateral effects for all asymmetry findings, and c the association between EEG asymmetry and a battery of cognitive tests. Results: We replicated our original findings, again demonstrating abnormal rightward inferior parietal beta asymmetry in adults with ADHD during the CPT, and again this metric exhibited abnormal reduced correlation to temporal-parietal beta asymmetry. Novel analyses also demonstrated a broader pattern of rightward beta and theta asymmetry across inferior, superior, and temporal-parietal brain regions, and showed that rightward parietal asymmetry in ADHD was atypically associated with multiple cognitive tests. Conclusion: Abnormal increased rightward parietal EEG beta asymmetry is an important feature of ADHD. We speculate that this phenotype may occur with any form of impaired capacity for top-down task-directed control over sensory encoding functions, and that it may reflect associated increases of attentional shifting and compensatory sustained/selective attention.

  4. The time-course of EEG alpha power changes in creative ideation.

    Science.gov (United States)

    Schwab, Daniela; Benedek, Mathias; Papousek, Ilona; Weiss, Elisabeth M; Fink, Andreas

    2014-01-01

    Increases in EEG alpha power during creative ideation are among the most consistent findings in the neuroscientific study of creativity, but existing studies did not focus on time-related changes of EEG alpha activity patterns during the process of creative ideation so far. Since several cognitive processes are involved in the generation of creative ideas, different EEG correlates may result as a function of time. In this study we addressed this crucial point. Forty-five participants worked on the "Alternative Uses Task" while the EEG was recorded and changes in task-related power (relative to rest) in the upper-frequency band (10-12 Hz) for three isochronous time intervals of the idea generation period were determined. Alpha power changes during idea generation followed a characteristic time course: we found a general increase of alpha power at the beginning of idea generation that was followed by a decrease and finally by a re-increase of alpha prior to responding that was most pronounced at parietal and temporal sites of the right hemisphere. Additionally, the production of more original ideas was accompanied by increasing hemispheric asymmetry (more alpha in the right than left hemisphere) with increasing duration of the idea generation period. The observed time course of brain activity may reflect the progression of different but well-known stages in the idea generation process: that is the initial retrieval of common and old ideas followed by the actual generation of novel and more creative ideas by overcoming typical responses through processes of mental simulation and imagination.

  5. Benign-malignant mass classification in mammogram using edge weighted local texture features

    Science.gov (United States)

    Rabidas, Rinku; Midya, Abhishek; Sadhu, Anup; Chakraborty, Jayasree

    2016-03-01

    This paper introduces novel Discriminative Robust Local Binary Pattern (DRLBP) and Discriminative Robust Local Ternary Pattern (DRLTP) for the classification of mammographic masses as benign or malignant. Mass is one of the common, however, challenging evidence of breast cancer in mammography and diagnosis of masses is a difficult task. Since DRLBP and DRLTP overcome the drawbacks of Local Binary Pattern (LBP) and Local Ternary Pattern (LTP) by discriminating a brighter object against the dark background and vice-versa, in addition to the preservation of the edge information along with the texture information, several edge-preserving texture features are extracted, in this study, from DRLBP and DRLTP. Finally, a Fisher Linear Discriminant Analysis method is incorporated with discriminating features, selected by stepwise logistic regression method, for the classification of benign and malignant masses. The performance characteristics of DRLBP and DRLTP features are evaluated using a ten-fold cross-validation technique with 58 masses from the mini-MIAS database, and the best result is observed with DRLBP having an area under the receiver operating characteristic curve of 0.982.

  6. EEG decoding of spoken words in bilingual listeners: from words to language invariant semantic-conceptual representations

    Directory of Open Access Journals (Sweden)

    João Mendonça Correia

    2015-02-01

    Full Text Available Spoken word recognition and production require fast transformations between acoustic, phonological and conceptual neural representations. Bilinguals perform these transformations in native and non-native languages, deriving unified semantic concepts from equivalent, but acoustically different words. Here we exploit this capacity of bilinguals to investigate input invariant semantic representations in the brain. We acquired EEG data while Dutch subjects, highly proficient in English listened to four monosyllabic and acoustically distinct animal words in both languages (e.g. ‘paard’-‘horse’. Multivariate pattern analysis (MVPA was applied to identify EEG response patterns that discriminate between individual words within one language (within-language discrimination and generalize meaning across two languages (across-language generalization. Furthermore, employing two EEG feature selection approaches, we assessed the contribution of temporal and oscillatory EEG features to our classification results. MVPA revealed that within-language discrimination was possible in a broad time-window (~50-620 ms after word onset probably reflecting acoustic-phonetic and semantic-conceptual differences between the words. Most interestingly, significant across-language generalization was possible around 550-600 ms, suggesting the activation of common semantic-conceptual representations from the Dutch and English nouns. Both types of classification, showed a strong contribution of oscillations below 12 Hz, indicating the importance of low frequency oscillations in the neural representation of individual words and concepts. This study demonstrates the feasibility of MVPA to decode individual spoken words from EEG responses and to assess the spectro-temporal dynamics of their language invariant semantic-conceptual representations. We discuss how this method and results could be relevant to track the neural mechanisms underlying conceptual encoding in

  7. Searching for "environmentally-benign" antifouling biocides.

    Science.gov (United States)

    Cui, Yan Ting; Teo, Serena L M; Leong, Wai; Chai, Christina L L

    2014-05-26

    As the result of the ecological impacts from the use of tributyltins (TBT) in shipping, environmental legislation for the registration of chemicals for use in the environment has grown to a monumental challenge requiring product dossiers to include information on the environmental fate and behavior of any chemicals. Specifically, persistence, bioaccumulation and toxicity, collectively known as PBT, are properties of concern in the assessment of chemicals. However, existing measurements of PBT properties are a cumbersome and expensive process, and thus not applied in the early stages of the product discovery and development. Inexpensive methods for preliminary PBT screening would minimize risks arising with the subsequent registration of products. In this article, we evaluated the PBT properties of compounds reported to possess anti-fouling properties using QSAR (quantitative structure-activity relationship) prediction programs such as BIOWIN™ (a biodegradation probability program), KOWWIN™ (log octanol-water partition coefficient calculation program) and ECOSAR™ (Ecological Structure Activity Relationship Programme). The analyses identified some small (Mr < 400) synthetic and natural products as potential candidates for environmentally benign biocides. We aim to demonstrate that while these methods of estimation have limitations, when applied with discretion, they are powerful tools useful in the early stages of research for compound selection for further development as anti-foulants.

  8. Benign Paroxysmal Positional Vertigo: An Integrated Perspective

    Directory of Open Access Journals (Sweden)

    Kourosh Parham

    2014-01-01

    Full Text Available Benign paroxysmal positional vertigo (BPPV, the most common cause of dizziness, occurs in all age groups. It presents with vertigo on head movement, but in older patients presentation may be typical and thus accounting for a low recognition rate in the primary care setting. It may be recurrent in up to 50% of cases. BPPV is associated with displacement of fragments of utricular otoconia into the semicircular canals, most commonly the posterior semicircular canal. Otoconia are composed of otoconin and otolin forming the organic matrix on which calcium carbonate mineralizes. Otoconia may fragment with trauma, age, or changes in the physiology of endolymph (e.g., pH and calcium concentration. Presentation varied because otoconia fragments can be displaced into any of the semicircular canals on either (or both side and may be free floating (canalolithiasis or attached to the cupula (cupulolithiasis. Most cases of BPPV are idiopathic, but head trauma, otologic disorders, and systemic disease appear to be contributory in a subset. Positional maneuvers are used to diagnose and treat the majority of cases. In rare intractable cases surgical management may be considered. A strong association with osteoporosis suggests that idiopathic BPPV may have diagnostic and management implications beyond that of a purely otologic condition.

  9. Clinical Investigation of Benign Asbestos Pleural Effusion.

    Science.gov (United States)

    Fujimoto, Nobukazu; Gemba, Kenichi; Aoe, Keisuke; Kato, Katsuya; Yokoyama, Takako; Usami, Ikuji; Onishi, Kazuo; Mizuhashi, Keiichi; Yusa, Toshikazu; Kishimoto, Takumi

    2015-01-01

    There is no detailed information about benign asbestos pleural effusion (BAPE). The aim of the study was to clarify the clinical features of BAPE. The criteria of enrolled patients were as follows: (1) history of asbestos exposure; (2) presence of pleural effusion determined by chest X-ray, CT, and thoracentesis; and (3) the absence of other causes of effusion. Clinical information was retrospectively analysed and the radiological images were reviewed. There were 110 BAPE patients between 1991 and 2012. All were males and the median age at diagnosis was 74 years. The median duration of asbestos exposure and period of latency for disease onset of BAPE were 31 and 48 years, respectively. Mean values of hyaluronic acid, adenosine deaminase, and carcinoembryonic antigen in the pleural fluid were 39,840 ng/mL, 23.9 IU/L, and 1.8 ng/mL, respectively. Pleural plaques were detected in 98 cases (89.1%). Asbestosis was present in 6 (5.5%) cases, rounded atelectasis was detected in 41 (37.3%) cases, and diffuse pleural thickening (DPT) was detected in 30 (27.3%) cases. One case developed lung cancer (LC) before and after BAPE. None of the cases developed malignant pleural mesothelioma (MPM) during the follow-up.

  10. Clinical Investigation of Benign Asbestos Pleural Effusion

    Directory of Open Access Journals (Sweden)

    Nobukazu Fujimoto

    2015-01-01

    Full Text Available There is no detailed information about benign asbestos pleural effusion (BAPE. The aim of the study was to clarify the clinical features of BAPE. The criteria of enrolled patients were as follows: (1 history of asbestos exposure; (2 presence of pleural effusion determined by chest X-ray, CT, and thoracentesis; and (3 the absence of other causes of effusion. Clinical information was retrospectively analysed and the radiological images were reviewed. There were 110 BAPE patients between 1991 and 2012. All were males and the median age at diagnosis was 74 years. The median duration of asbestos exposure and period of latency for disease onset of BAPE were 31 and 48 years, respectively. Mean values of hyaluronic acid, adenosine deaminase, and carcinoembryonic antigen in the pleural fluid were 39,840 ng/mL, 23.9 IU/L, and 1.8 ng/mL, respectively. Pleural plaques were detected in 98 cases (89.1%. Asbestosis was present in 6 (5.5% cases, rounded atelectasis was detected in 41 (37.3% cases, and diffuse pleural thickening (DPT was detected in 30 (27.3% cases. One case developed lung cancer (LC before and after BAPE. None of the cases developed malignant pleural mesothelioma (MPM during the follow-up.

  11. Benign encephalopathy of pregnancy. Preliminary clinical observations.

    Science.gov (United States)

    Poser, C M; Kassirer, M R; Peyser, J M

    1986-01-01

    A survey of 67 pregnancies in 51 professional women (physicians, psychologists, nurses, administrators, etc.) revealed the occurrence of symptoms of cognitive dysfunction such as forgetfulness, disorientation, confusion and reading difficulties in 28 pregnancies occurring in 21 women. These were unrelated to such factors as age of delivery, percentage weight gain, the baby's sex or birth weight, alcohol consumption, smoking, a history of migraine or allergy or other symptoms occurring during pregnancy such as sleepiness and lack of concentration, irritability, loss of interest in job or nightmares. Nor was there any correlation with hypertension, proteinuria, glycosuria, ketonuria, anemia, or morning sickness. Furthermore, these cognitive disturbances were not related to depression or sleep deprivation. Despite these symptoms, none of the women suffering from them were forced to interrupt their professional activities during pregnancy. The syndrome of benign encephalopathy of pregnancy should be recognized so that simple precautions can be taken to prevent any interference with professional or other activities. The etiology of the syndrome is unknown.

  12. Treating benign prostatic hyperplasia with botulinum neurotoxin.

    Science.gov (United States)

    Brisinda, G; Vanella, S; Marniga, G; Crocco, A; Maria, G

    2011-01-01

    Botulinum toxin (BoNT) has been increasingly used in the interventional treatment of several disorders; the use of this agent has extended to a plethora of conditions including focal dystonia, spasticity, inappropriate contraction in most gastrointestinal sphincters, eye movement disorders, hyperhidrosis, genitourinary disorders and aesthetically undesirable hyperfunctional facial lines. In addition, BoNT is being investigated for the control of pain, and for the management of tension or migraine headaches and myofascial pain syndrome. Benign prostatic hyperplasia (BPH) is a common condition in ageing men; the goal of therapy is to reduce the lower urinary tract symptoms (LUTS) associated with BPH and to improve the quality of life. However, medical treatment, including drugs that relax smooth muscle within the prostate and drugs that shrink the gland are not totally effective or without complications. The standard surgical treatment for BPH is progressively changing to minimally invasive therapies, but none of them has provided clear results. The use of BoNT-A to inhibit the autonomic efferent effects on prostate growth and contraction, and inhibit the abnormal afferent effects on prostate sensation, might be an alternative treatment for BPH. BoNT injections have several advantages over drugs and surgical therapies in the management of intractable or chronic disease; systemic pharmacologic effects are rare, permanent destruction of tissue does not occur, and graded degrees of relaxation may be achieved by varying the dose injected. In this paper, clinical experience over the last years with BoNT in BPH impaired patients will be illustrated.

  13. [Minimally Invasive Treatment of Esophageal Benign Diseases].

    Science.gov (United States)

    Inoue, Haruhiro

    2016-07-01

    As a minimally invasive treatment of esophageal achalasia per-oral endoscopic myotomy( POEM) was developed in 2008. More than 1,100 cases of achalasia-related diseases received POEM. Success rate of the procedure was more than 95%(Eckerdt score improvement 3 points and more). No serious( Clavian-Dindo classification III b and more) complication was experienced. These results suggest that POEM becomes a standard minimally invasive treatment for achalasia-related diseases. As an off-shoot of POEM submucosal tumor removal through submucosal tunnel (per-oral endoscopic tumor resection:POET) was developed and safely performed. Best indication of POET is less than 5 cm esophageal leiomyoma. A novel endoscopic treatment of gastroesophageal reflux disease (GERD) was developed. Anti-reflux mucosectomy( ARMS) is nearly circumferential mucosal reduction of gastric cardia mucosa. ARMS is performed in 56 consecutive cases of refractory GERD. No major complications were encountered and excellent clinical results. Best indication of ARMS is a refractory GERD without long sliding hernia. Longest follow-up case is more than 10 years. Minimally invasive treatments for esophageal benign diseases are currently performed by therapeutic endoscopy.

  14. [Benign pleural effusion caused by asbestos exposure].

    Science.gov (United States)

    Vieira, J R; Alfarroba, E; Viegas, J; Freitas e Costa, M

    1992-05-01

    The Authors present the first case described among us of benign pleural effusion of an asbestotic origin. They stress the importance of thoracoscopy (pleuroscopy) in the diagnosis of this situation. Attention is drawn to the fact that asbestotic lesions and asbestotic bodies have been found in the lung and, in particular, in the parietal pleura as well. They emphasize the fact that exposure to asbestos was not realized by the patient, which made the clarification of the situation more difficult. It was a CT scan that showed the signs suggestive of exposure to asbestos which raised the diagnostic suspicion. They conclude that every patient with a pleural effusion must be thoroughly questioned about exposure to asbestos. Even if the exposure is accepted, they consider that one should proceed to a pleuro-pulmonar biopsy by thoracoscopy. This biopsy allows demonstration of the characteristic histopathological lesions and rule out other etiologies, namely malignancy and tuberculosis. They suggest that these patients must be highly motivated to stop any smoking and kept under periodic surveillance.

  15. Transurethral electrochemical treatment of benign prostatic hyperplasia

    Institute of Scientific and Technical Information of China (English)

    张民; 龚侃; 李宁; 曾荔; 那彦群

    2003-01-01

    Objective To study the mechanism and feasibility of transurethral electrochemical therapy for the treatment of benign prostatic hyperplasia (BPH). Methods Between March 1998 and March 2000, specifically designed devices and catheters for electrochemical therapy were applied to 6 prostate specimens obtained by suprapubic prostatectomy in order to treat BPH patients with urinary retention for whom surgery was contraindicated. Sixteen patients (with a mean age of 77.3 years old) underwent electrical treatment totaling 160-220 coulombs under topical urethral anesthesia for 68-132 min. The catheters remained inside the patient for 7-10 d. Results Irreversible destructive changes occurred within cathodal tissue, while carbonization occurred within anodic tissue. The radius of tissue change was 7-8 mm and 1-2 mm, respectively. In vivo trial: 11 (69%) patients could be weaned off the catheters with satisfactory urination. Three months after therapy, the mean international prostate symptom score (IPSS) was 14.5, mean peak flow rate was 10.5 ml/s, and mean residual urine was 39 ml. No serious complications were observed. Conclusion Transurethral electrochemical treatment is potentially a minimally invasive alternative for treatment of BPH, especially for elderly patients at high risk.

  16. Transurethral microwave thermotherapy for benign prostatic hyperplasia

    Directory of Open Access Journals (Sweden)

    Rubeinstein Jonathan N.

    2003-01-01

    Full Text Available Transurethral resection of the prostate (TURP remains the gold standard for treatment of benign prostatic hyperplasia (BPH. In general, while this procedure is safe, patients require a spinal, epidural, or general anesthesia and often several days of hospital stay; the potential morbidity and mortality limits the use of TURP in high-risk patients. Pharmacotherapy has been recommended as a first-line therapy for all patients with mild to moderate symptoms. Patients are oftentimes enthusiastic if they are offered a one-time method to treat lower urinary tract symptoms secondary to BPH, provided that the method offers reduced risk and allows an efficacy equal to that of medical therapy. One such method is transurethral microwave thermotherapy (TUMT. TUMT involves the insertion of a specially designed urinary catheter with a microwave antenna, which heats the prostate and destroys hyperplastic prostate tissue. TUMT allows the avoidance of general or regional anesthesia, and results in minimal blood loss and fluid absorption. In this review, the authors discussed the current indications and outcome of TUMT, including the history of the procedure, the mechanism of action, the indications for TUMT, the pre-operative considerations, the patient selection, the results in terms of efficacy, by comparing TUMT vs. Sham, TUMT vs. Alpha-blocker and TUMT vs. TURP. Finally, the complications are presented, as well as other uses and future directions of the procedure. The authors concluded that TUMT is a safe and effective minimally invasive alternative to treatment of symptomatic BPH.

  17. Nonlinear analysis of EEG for epileptic seizures

    Energy Technology Data Exchange (ETDEWEB)

    Hively, L.M.; Clapp, N.E.; Daw, C.S.; Lawkins, W.F. [Oak Ridge National Lab., TN (United States); Eisenstadt, M.L. [Knoxville Neurology Clinic, St. Mary`s Medical Center, Knoxville, TN (United States)

    1995-04-01

    We apply chaotic time series analysis (CTSA) to human electroencephalogram (EEG) data. Three epoches were examined: epileptic seizure, non-seizure, and transition from non-seizure to seizure. The CTSA tools were applied to four forms of these data: raw EEG data (e-data), artifact data (f-data) via application of a quadratic zero-phase filter of the raw data, artifact-filtered data (g- data) and that was the residual after subtracting f-data from e-data, and a low-pass-filtered version (h-data) of g-data. Two different seizures were analyzed for the same patient. Several nonlinear measures uniquely indicate an epileptic seizure in both cases, including an abrupt decrease in the time per wave cycle in f-data, an abrupt increase in the Kolmogorov entropy and in the correlation dimension for e-h data, and an abrupt increase in the correlation dimension for e-h data. The transition from normal to seizure state also is characterized by distinctly different trends in the nonlinear measures for each seizure and may be potential seizure predictors for this patient. Surrogate analysis of e-data shows that statistically significant nonlinear structure is present during the non-seizure, transition , and seizure epoches.

  18. Spatiotemporal Analysis of Multichannel EEG: CARTOOL

    Directory of Open Access Journals (Sweden)

    Denis Brunet

    2011-01-01

    Full Text Available This paper describes methods to analyze the brain's electric fields recorded with multichannel Electroencephalogram (EEG and demonstrates their implementation in the software CARTOOL. It focuses on the analysis of the spatial properties of these fields and on quantitative assessment of changes of field topographies across time, experimental conditions, or populations. Topographic analyses are advantageous because they are reference independents and thus render statistically unambiguous results. Neurophysiologically, differences in topography directly indicate changes in the configuration of the active neuronal sources in the brain. We describe global measures of field strength and field similarities, temporal segmentation based on topographic variations, topographic analysis in the frequency domain, topographic statistical analysis, and source imaging based on distributed inverse solutions. All analysis methods are implemented in a freely available academic software package called CARTOOL. Besides providing these analysis tools, CARTOOL is particularly designed to visualize the data and the analysis results using 3-dimensional display routines that allow rapid manipulation and animation of 3D images. CARTOOL therefore is a helpful tool for researchers as well as for clinicians to interpret multichannel EEG and evoked potentials in a global, comprehensive, and unambiguous way.

  19. Spatiotemporal analysis of multichannel EEG: CARTOOL.

    Science.gov (United States)

    Brunet, Denis; Murray, Micah M; Michel, Christoph M

    2011-01-01

    This paper describes methods to analyze the brain's electric fields recorded with multichannel Electroencephalogram (EEG) and demonstrates their implementation in the software CARTOOL. It focuses on the analysis of the spatial properties of these fields and on quantitative assessment of changes of field topographies across time, experimental conditions, or populations. Topographic analyses are advantageous because they are reference independents and thus render statistically unambiguous results. Neurophysiologically, differences in topography directly indicate changes in the configuration of the active neuronal sources in the brain. We describe global measures of field strength and field similarities, temporal segmentation based on topographic variations, topographic analysis in the frequency domain, topographic statistical analysis, and source imaging based on distributed inverse solutions. All analysis methods are implemented in a freely available academic software package called CARTOOL. Besides providing these analysis tools, CARTOOL is particularly designed to visualize the data and the analysis results using 3-dimensional display routines that allow rapid manipulation and animation of 3D images. CARTOOL therefore is a helpful tool for researchers as well as for clinicians to interpret multichannel EEG and evoked potentials in a global, comprehensive, and unambiguous way.

  20. Differences in resting EEG related to ability.

    Science.gov (United States)

    Jausovec, N; Jausovec, K

    2000-01-01

    The aim of the present study was to investigate the relationship between different EEG measures (mean power, mean frequency, approximated entropy and coherence), and ability (creativity and intelligence). For that purpose the EEG of 115 student-teachers (Intelligence: M= 115.17; SD = 12.78; IQ(min)= 82; IQ(max)= 136; Creativity - standardized scores: M = 55.97; SD = 10.67; C(min)= 38; C(max)= 84) was recorded while they were resting with eyes open and closed. The study showed only weak correlations between measures based on the level of activity in different areas (mean power, mean frequency and approximated entropy) and creativity. The correlations with IQ scores were even less pronounced. On the other hand, coherence measures showed a much more intense relationship both with creativity as well as with intelligence. In the eyes-open state these differences were mainly distributed over the right hemisphere. The results are discussed in the light of different theories relating brain functioning and ability.