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  1. Book ; Online ; E-Book: Dynamics of neural networks

    Putten, Michel J. A. M. van

    a mathematical and clinical approach

    2021  

    Author's details Michel J. A. M. van Putten
    Keywords Electronic books
    Language English
    Size 1 Online-Ressource (xvii, 259 Seiten), Illustrationen, Diagramme
    Publisher Springer
    Publishing place Berlin
    Publishing country Germany
    Document type Book ; Online ; E-Book
    Remark Zugriff für angemeldete ZB MED-Nutzerinnen und -Nutzer
    HBZ-ID HT021211762
    ISBN 978-3-662-61184-5 ; 9783662611821 ; 3-662-61184-8 ; 3662611821
    DOI 10.1007/978-3-662-61184-5
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  2. Article ; Online: Prediction in cultured cortical neural networks.

    Lamberti, Martina / Tripathi, Shiven / van Putten, Michel J A M / Marzen, Sarah / le Feber, Joost

    PNAS nexus

    2023  Volume 2, Issue 6, Page(s) pgad188

    Abstract: Theory suggest that networks of neurons may predict their input. Prediction may underlie most aspects of information processing and is believed to be involved in motor and cognitive control and decision-making. Retinal cells have been shown to be capable ...

    Abstract Theory suggest that networks of neurons may predict their input. Prediction may underlie most aspects of information processing and is believed to be involved in motor and cognitive control and decision-making. Retinal cells have been shown to be capable of predicting visual stimuli, and there is some evidence for prediction of input in the visual cortex and hippocampus. However, there is no proof that the ability to predict is a generic feature of neural networks. We investigated whether random in vitro neuronal networks can predict stimulation, and how prediction is related to short- and long-term memory. To answer these questions, we applied two different stimulation modalities. Focal electrical stimulation has been shown to induce long-term memory traces, whereas global optogenetic stimulation did not. We used mutual information to quantify how much activity recorded from these networks reduces the uncertainty of upcoming stimuli (prediction) or recent past stimuli (short-term memory). Cortical neural networks did predict future stimuli, with the majority of all predictive information provided by the immediate network response to the stimulus. Interestingly, prediction strongly depended on short-term memory of recent sensory inputs during focal as well as global stimulation. However, prediction required less short-term memory during focal stimulation. Furthermore, the dependency on short-term memory decreased during 20 h of focal stimulation, when long-term connectivity changes were induced. These changes are fundamental for long-term memory formation, suggesting that besides short-term memory the formation of long-term memory traces may play a role in efficient prediction.
    Language English
    Publishing date 2023-06-27
    Publishing country England
    Document type Journal Article
    ISSN 2752-6542
    ISSN (online) 2752-6542
    DOI 10.1093/pnasnexus/pgad188
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Feasibility and repeatability of ultrasound-guided surface electroenterography to measure colonic slow wave motility in healthy adults.

    Rolleman, Nick H / Visser, Iris M / Klein, Willemijn M / Van Putten, Michel J A M / De Blaauw, Ivo / Botden, Sanne M B I

    BMC gastroenterology

    2024  Volume 24, Issue 1, Page(s) 114

    Abstract: Surface electroenterography is a potential non-invasive alternative to current diagnostics of colonic motility disorders. However, electrode positioning in electroenterography is often based on general anatomy and may lack generalizability. Furthermore, ... ...

    Abstract Surface electroenterography is a potential non-invasive alternative to current diagnostics of colonic motility disorders. However, electrode positioning in electroenterography is often based on general anatomy and may lack generalizability. Furthermore, the repeatability of electroenterography measurements is unknown. This study aimed to evaluate ultrasound-guided electrode positioning for electroenterography measurements and to determine the repeatability of those measurements. In ten healthy adults, two electroenterography procedures were performed, consisting of fasting, ultrasound-guided electrode localization and two 20-minute electroenterography recordings separated by a meal. The dominant frequency, the mean power density (magnitude of colonic motility) and the power percent difference (relative pre- to postprandial increase in magnitude) were determined. Repeatability was determined by Lin's concordance correlation coefficient. The results demonstrated that the dominant frequency did not differ between pre- and postprandial recordings and was 3 cpm, characteristic of colonic motility. The mean power density increased between the pre- and postprandial measurements, with an average difference of over 200%. The repeatability of both the dominant frequency and power density was poor to moderate, whereas the correlation coefficient of the power percent difference was poor. Concluding, ultrasound-guided surface electroenterography seems able to measure the gastrocolic reflex, but the dissatisfactory repeatability necessitates optimization of the measurement protocol.
    MeSH term(s) Adult ; Humans ; Feasibility Studies ; Colon/diagnostic imaging ; Fasting ; Ultrasonography, Interventional ; Gastrointestinal Motility
    Language English
    Publishing date 2024-03-18
    Publishing country England
    Document type Journal Article
    ZDB-ID 2041351-8
    ISSN 1471-230X ; 1471-230X
    ISSN (online) 1471-230X
    ISSN 1471-230X
    DOI 10.1186/s12876-024-03196-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Ultrafast review of ambulatory EEGs with deep learning.

    da Silva Lourenço, Catarina / Tjepkema-Cloostermans, Marleen C / van Putten, Michel J A M

    Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology

    2023  Volume 154, Page(s) 43–48

    Abstract: Objective: Interictal epileptiform discharges (IED) are hallmark biomarkers of epilepsy which are typically detected through visual analysis. Deep learning has shown potential in automating IED detection, which could reduce the burden of visual analysis ...

    Abstract Objective: Interictal epileptiform discharges (IED) are hallmark biomarkers of epilepsy which are typically detected through visual analysis. Deep learning has shown potential in automating IED detection, which could reduce the burden of visual analysis in clinical practice. This is particularly relevant for ambulatory electroencephalograms (EEGs), as these entail longer review times.
    Methods: We applied a previously trained neural network to an independent dataset of 100 ambulatory EEGs (average duration 20.6 h). From these, 42 EEGs contained IEDs, 25 were abnormal without IEDs and 33 were normal. The algorithm flagged 2 second epochs that it considered IEDs. The EEGs were provided to an expert, who used NeuroCenter EEG to review the recordings. The expert concluded if each recording contained IEDs, and was timed during the process.
    Results: The conclusion of the reviewer was the same as the EEG report in 97% of the recordings. Three EEGs contained IEDs that were not detected based on the flagged epochs. Review time for the 100 EEGs was approximately 4 h, with half of the recordings taking <2 minutes to review.
    Conclusions: Our network can be used to reduce time spent on visual analysis in the clinic by 50-75 times with high reliability.
    Significance: Given the large time reduction potential and high success rate, this algorithm can be used in the clinic to aid in visual analysis.
    MeSH term(s) Humans ; Deep Learning ; Reproducibility of Results ; Epilepsy/diagnosis ; Electroencephalography ; Neural Networks, Computer
    Language English
    Publishing date 2023-07-27
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1463630-x
    ISSN 1872-8952 ; 0921-884X ; 1388-2457
    ISSN (online) 1872-8952
    ISSN 0921-884X ; 1388-2457
    DOI 10.1016/j.clinph.2023.07.005
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Preservation of thalamocortical circuitry is essential for good recovery after cardiac arrest.

    Tewarie, Prejaas K B / Tjepkema-Cloostermans, Marleen C / Abeysuriya, Romesh G / Hofmeijer, Jeannette / van Putten, Michel J A M

    PNAS nexus

    2023  Volume 2, Issue 5, Page(s) pgad119

    Abstract: Continuous electroencephalographam (EEG) monitoring contributes to prediction of neurological outcome in comatose cardiac arrest survivors. While the phenomenology of EEG abnormalities in postanoxic encephalopathy is well known, the pathophysiology, ... ...

    Abstract Continuous electroencephalographam (EEG) monitoring contributes to prediction of neurological outcome in comatose cardiac arrest survivors. While the phenomenology of EEG abnormalities in postanoxic encephalopathy is well known, the pathophysiology, especially the presumed role of selective synaptic failure, is less understood. To further this understanding, we estimate biophysical model parameters from the EEG power spectra from individual patients with a good or poor recovery from a postanoxic encephalopathy. This biophysical model includes intracortical, intrathalamic, and corticothalamic synaptic strengths, as well as synaptic time constants and axonal conduction delays. We used continuous EEG measurements from hundred comatose patients recorded during the first 48 h postcardiac arrest, 50 with a poor neurological outcome [cerebral performance category
    Language English
    Publishing date 2023-04-06
    Publishing country England
    Document type Journal Article
    ISSN 2752-6542
    ISSN (online) 2752-6542
    DOI 10.1093/pnasnexus/pgad119
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Book: Essentials of neurophysiology

    Putten, Michel J. A. M. van

    basic concepts and clinical applications for scientists and engineers

    (Series in biomedical engineering)

    2009  

    Author's details Michel J. A. M. van Putten
    Series title Series in biomedical engineering
    Keywords Neurophysiology ; Neurophysiologie
    Subject Nervenphysiologie ; Nervensystem
    Language English
    Size XVII, 231 S. : Ill., graph. Darst.
    Publisher Springer
    Publishing place Berlin u.a.
    Publishing country Germany
    Document type Book
    HBZ-ID HT015598798
    ISBN 978-3-540-69889-0 ; 3-540-69889-2
    Database Catalogue ZB MED Medicine, Health

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  7. Article ; Online: Infraslow activity as a potential modulator of corticomotor excitability.

    de Goede, Annika A / van Putten, Michel J A M

    Journal of neurophysiology

    2019  Volume 122, Issue 1, Page(s) 325–335

    Abstract: Fluctuations in cortical excitability are a candidate mechanism involved in the trial-to-trial variation of motor evoked potentials (MEPs) to transcranial magnetic stimulation (TMS). We explore whether infraslow EEG activity (<0.1 Hz) modulates ... ...

    Abstract Fluctuations in cortical excitability are a candidate mechanism involved in the trial-to-trial variation of motor evoked potentials (MEPs) to transcranial magnetic stimulation (TMS). We explore whether infraslow EEG activity (<0.1 Hz) modulates corticomotor excitability by evaluating the presence of temporal and phase clustering of TMS-induced MEPs. In addition, we evaluate the dependence of MEP amplitude on the phase of the infraslow activity. Twenty-three subjects were stimulated at an intensity above the resting motor threshold (rMT) and ten at the rMT. We evaluated whether temporal and phase clustering of MEP size and MEP generation were present, using 1,000 surrogates with a similar amplitude or occurrence distribution. To evaluate the MEP amplitude dependence, we used the least-square method to approximate the linear circular data by fitting a sine function. We observed significant temporal clustering at a group level, in all individual subjects stimulated at rMT and in the majority of those stimulated above rMT, suggesting underlying determinism of corticomotor excitability instead of randomly generated fluctuations. The majority of subjects showed significant phase clustering for MEP size and for MEP occurrence, and significant phase clustering was found at the group level. Furthermore, in approximately one-quarter to one-half of the subjects we found a significant correlation and dependence of MEP amplitude on the phase of infraslow activity, respectively. Although other mechanisms very likely contribute as well, our findings seem to suggest that infraslow activity is involved in the variability of cortical excitability and TMS-induced responses.
    MeSH term(s) Adult ; Electroencephalography ; Evoked Potentials, Motor ; Female ; Humans ; Male ; Middle Aged ; Motor Cortex/physiology ; Reaction Time ; Transcranial Magnetic Stimulation
    Language English
    Publishing date 2019-05-22
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 80161-6
    ISSN 1522-1598 ; 0022-3077
    ISSN (online) 1522-1598
    ISSN 0022-3077
    DOI 10.1152/jn.00663.2018
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Restoration of postictal cortical activity after electroconvulsive therapy relates to recovery of orientation in person, place, and time.

    Stuiver, Sven / Pottkämper, Julia C M / Verdijk, Joey P A J / Ten Doesschate, Freek / van Putten, Michel J A M / Hofmeijer, Jeannette / van Waarde, Jeroen A

    European psychiatry : the journal of the Association of European Psychiatrists

    2024  Volume 67, Issue 1, Page(s) e16

    Abstract: Background: Most patients show temporary impairments in clinical orientation after electroconvulsive therapy (ECT)-induced seizures. It is unclear how postictal reorientation relates to electroencephalography (EEG) restoration. This relationship may ... ...

    Abstract Background: Most patients show temporary impairments in clinical orientation after electroconvulsive therapy (ECT)-induced seizures. It is unclear how postictal reorientation relates to electroencephalography (EEG) restoration. This relationship may provide additional measures to quantify postictal recovery and shed light on neurophysiological aspects of reorientation after ECT.
    Methods: We analyzed prospectively collected clinical and continuous ictal and postictal EEG data from ECT patients. Postictal EEG restoration up to 1 h was estimated by the evolution of the normalized alpha-delta ratio (ADR). Times to reorientation in the cognitive domains of person, place, and time were assessed postictally. In each cognitive domain, a linear mixed model was fitted to investigate the relationships between time to reorientation and postictal EEG restoration.
    Results: In total, 272 pairs of ictal-postictal EEG and reorientation times of 32 patients were included. In all domains, longer time to reorientation was associated with slower postictal EEG recovery. Longer seizure duration and postictal administration of midazolam were related to longer time to reorientation in all domains. At 1-hour post-seizure, most patients were clinically reoriented, while their EEG had only partly restored.
    Conclusions: We show a relationship between postictal EEG restoration and clinical reorientation after ECT-induced seizures. EEG was more sensitive than reorientation time in all domains to detect postictal recovery beyond 1-hour post-seizure. Our findings indicate that clinical reorientation probably depends on gradual cortical synaptic recovery, with longer seizure duration leading to longer postsynaptic suppression after ECT seizures.
    MeSH term(s) Humans ; Electroconvulsive Therapy ; Seizures/therapy ; Time Factors ; Electroencephalography
    Language English
    Publishing date 2024-02-14
    Publishing country England
    Document type Journal Article
    ZDB-ID 1074337-6
    ISSN 1778-3585 ; 0767-399X ; 0924-9338
    ISSN (online) 1778-3585
    ISSN 0767-399X ; 0924-9338
    DOI 10.1192/j.eurpsy.2024.10
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Ghrelin for Neuroprotection in Post-Cardiac Arrest Coma: A Randomized Clinical Trial.

    Nutma, Sjoukje / Beishuizen, Albertus / van den Bergh, Walter M / Foudraine, Norbert A / le Feber, Joost / Filius, P Margreet G / Cornet, Alexander D / van der Palen, Job / van Putten, Michel J A M / Hofmeijer, Jeannette

    JAMA neurology

    2024  

    Abstract: Importance: Out-of-hospital cardiac arrest survival rates have markedly risen in the last decades, but neurological outcome only improved marginally. Despite research on more than 20 neuroprotective strategies involving patients in comas after cardiac ... ...

    Abstract Importance: Out-of-hospital cardiac arrest survival rates have markedly risen in the last decades, but neurological outcome only improved marginally. Despite research on more than 20 neuroprotective strategies involving patients in comas after cardiac arrest, none have demonstrated unequivocal evidence of efficacy; however, treatment with acyl-ghrelin has shown improved functional and histological brain recovery in experimental models of cardiac arrest and was safe in a wide variety of human study populations.
    Objective: To determine safety and potential efficacy of intravenous acyl-ghrelin to improve neurological outcome in patients in a coma after cardiac arrest.
    Design, setting, and participants: A phase 2, double-blind, placebo-controlled, multicenter, randomized clinical trial, Ghrelin Treatment of Comatose Patients After Cardiac Arrest: A Clinical Trial to Promote Cerebral Recovery (GRECO), was conducted between January 18, 2019, and October 17, 2022. Adult patients 18 years or older who were in a comatose state after cardiac arrest were assessed for eligibility; patients were from 3 intensive care units in the Netherlands. Expected death within 48 hours or unfeasibility of treatment initiation within 12 hours were exclusion criteria.
    Interventions: Patients were randomized to receive intravenous acyl-ghrelin, 600 μg (intervention group), or placebo (control group) within 12 hours after cardiac arrest, continued for 7 days, twice daily, in addition to standard care.
    Main outcomes and measures: Primary outcome was the score on the Cerebral Performance Categories (CPC) scale at 6 months. Safety outcomes included any serious adverse events. Secondary outcomes were mortality and neuron-specific enolase (NSE) levels on days 1 and 3.
    Results: A total of 783 adult patients in a coma after cardiac arrest were assessed for eligibility, and 160 patients (median [IQR] age, 68 [57-75] years; 120 male [75%]) were enrolled. A total of 81 patients (51%) were assigned to the intervention group, and 79 (49%) were assigned to the control group. The common odds ratio (OR) for any CPC improvement in the intervention group was 1.78 (95% CI, 0.98-3.22; P = .06). This was consistent over all CPC categories. Mean (SD) NSE levels on day 1 after cardiac arrest were significantly lower in the intervention group (34 [6] μg/L vs 56 [13] μg/L; P = .04) and on day 3 (28 [6] μg/L vs 52 [14] μg/L; P = .08). Serious adverse events were comparable in incidence and type between the groups. Mortality was 37% (30 of 81) in the intervention group vs 51% (40 of 79) in the control group (absolute risk reduction, 14%; 95% CI, -2% to 29%; P = .08).
    Conclusions and relevance: In patients in a coma after cardiac arrest, intravenous treatment with acyl-ghrelin was safe and potentially effective to improve neurological outcome. Phase 3 trials are needed for conclusive evidence.
    Trial registration: Clinicaltrialsregister.eu: EUCTR2018-000005-23-NL.
    Language English
    Publishing date 2024-05-06
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2702023-X
    ISSN 2168-6157 ; 2168-6149
    ISSN (online) 2168-6157
    ISSN 2168-6149
    DOI 10.1001/jamaneurol.2024.1088
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Neurophysiological signatures of mild traumatic brain injury in the acute and subacute phase.

    Barone, Valentina / de Koning, Myrthe E / van der Horn, Harm J / van der Naalt, Joukje / Eertman-Meyer, Carin J / van Putten, Michel J A M

    Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology

    2024  

    Abstract: Background: Mild traumatic brain injury (mTBI) affects 48 million people annually, with up to 30% experiencing long-term complaints such as fatigue, blurred vision, and poor concentration. Assessing neurophysiological features related to visual ... ...

    Abstract Background: Mild traumatic brain injury (mTBI) affects 48 million people annually, with up to 30% experiencing long-term complaints such as fatigue, blurred vision, and poor concentration. Assessing neurophysiological features related to visual attention and outcome measures aids in understanding clinical symptoms and prognostication.
    Methods: We recorded EEG and eye movements in mTBI patients during a computerized task performed in the acute (< 24 h, TBI-A) and subacute phase (4-6 weeks thereafter). We estimated the posterior dominant rhythm, reaction times (RTs), fixation duration, and event-related potentials (ERPs). Clinical outcome measures were assessed using the Head Injury Symptom Checklist (HISC) and the Extended Glasgow Outcome Scale (GOSE) at 6 months post-injury. Similar analyses were performed in an age-matched control group (measured once). Linear mixed effect modeling was used to examine group differences and temporal changes within the mTBI group.
    Results: Twenty-nine patients were included in the acute phase, 30 in the subacute phase, and 19 controls. RTs and fixation duration were longer in mTBI patients compared to controls (p < 0.05), but not between TBI-A and TBI-S (p < 0.05). The frequency of the posterior dominant rhythm was significantly slower in TBI-A (0.6 Hz, p < 0.05) than TBI-S. ERP mean amplitude was significantly lower in mTBI patients than in controls. Neurophysiological features did not significantly relate to clinical outcome measures.
    Conclusion: mTBI patients demonstrate impaired processing speed and stimulus evaluation compared to controls, persisting up to 6 weeks after injury. Neurophysiological features in mTBI can assist in determining the extent and temporal progression of recovery.
    Language English
    Publishing date 2024-02-17
    Publishing country Italy
    Document type Journal Article
    ZDB-ID 2016546-8
    ISSN 1590-3478 ; 1590-1874
    ISSN (online) 1590-3478
    ISSN 1590-1874
    DOI 10.1007/s10072-024-07364-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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