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Reichert C, Sweeney-Reed CM, Hinrichs H, Dürschmid S. A toolbox for decoding BCI commands based on event-related potentials. Front Hum Neurosci 2024; 18:1358809. [PMID: 38505100 PMCID: PMC10949531 DOI: 10.3389/fnhum.2024.1358809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 02/14/2024] [Indexed: 03/21/2024] Open
Abstract
Commands in brain-computer interface (BCI) applications often rely on the decoding of event-related potentials (ERP). For instance, the P300 potential is frequently used as a marker of attention to an oddball event. Error-related potentials and the N2pc signal are further examples of ERPs used for BCI control. One challenge in decoding brain activity from the electroencephalogram (EEG) is the selection of the most suitable channels and appropriate features for a particular classification approach. Here we introduce a toolbox that enables ERP-based decoding using the full set of channels, while automatically extracting informative components from relevant channels. The strength of our approach is that it handles sequences of stimuli that encode multiple items using binary classification, such as target vs. nontarget events typically used in ERP-based spellers. We demonstrate examples of application scenarios and evaluate the performance of four openly available datasets: a P300-based matrix speller, a P300-based rapid serial visual presentation (RSVP) speller, a binary BCI based on the N2pc, and a dataset capturing error potentials. We show that our approach achieves performances comparable to those in the original papers, with the advantage that only conventional preprocessing is required by the user, while channel weighting and decoding algorithms are internally performed. Thus, we provide a tool to reliably decode ERPs for BCI use with minimal programming requirements.
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Affiliation(s)
- Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Catherine M. Sweeney-Reed
- Neurocybernetics and Rehabilitation, Department of Neurology, Otto von Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany
| | - Hermann Hinrichs
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany
- Department of Neurology, Otto von Guericke University, Magdeburg, Germany
| | - Stefan Dürschmid
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States
- Department of Cellular Neuroscience, Leibniz Institute for Neurobiology, Magdeburg, Germany
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2
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Kalyani A, Contier O, Klemm L, Azañon E, Schreiber S, Speck O, Reichert C, Kuehn E. Reduced dimension stimulus decoding and column-based modeling reveal architectural differences of primary somatosensory finger maps between younger and older adults. Neuroimage 2023; 283:120430. [PMID: 37923281 DOI: 10.1016/j.neuroimage.2023.120430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 09/28/2023] [Accepted: 10/25/2023] [Indexed: 11/07/2023] Open
Abstract
The primary somatosensory cortex (SI) contains fine-grained tactile representations of the body, arranged in an orderly fashion. The use of ultra-high resolution fMRI data to detect group differences, for example between younger and older adults' SI maps, is challenging, because group alignment often does not preserve the high spatial detail of the data. Here, we use robust-shared response modeling (rSRM) that allows group analyses by mapping individual stimulus-driven responses to a lower dimensional shared feature space, to detect age-related differences in tactile representations between younger and older adults using 7T-fMRI data. Using this method, we show that finger representations are more precise in Brodmann-Area (BA) 3b and BA1 compared to BA2 and motor areas, and that this hierarchical processing is preserved across age groups. By combining rSRM with column-based decoding (C-SRM), we further show that the number of columns that optimally describes finger maps in SI is higher in younger compared to older adults in BA1, indicating a greater columnar size in older adults' SI. Taken together, we conclude that rSRM is suitable for finding fine-grained group differences in ultra-high resolution fMRI data, and we provide first evidence that the columnar architecture in SI changes with increasing age.
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Affiliation(s)
- Avinash Kalyani
- Institute for Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, 39120, Germany; German Center for Neurodegenerative Diseases (DZNE), Magdeburg, 39120, Germany.
| | - Oliver Contier
- Vision and Computational Cognition Group, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, 04103, Germany; Max Planck School of Cognition, Stephanstrasse 1a, Leipzig, 04103, Germany
| | - Lisa Klemm
- Leibniz Institute for Neurobiology (LIN), Otto-von-Guericke University Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS) Magdeburg, Magdeburg, 39120, Germany; Clinic for Neurology, Otto-von-Guericke University Magdeburg, 39120, Germany
| | - Elena Azañon
- Leibniz Institute for Neurobiology (LIN), Otto-von-Guericke University Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS) Magdeburg, Magdeburg, 39120, Germany; Clinic for Neurology, Otto-von-Guericke University Magdeburg, 39120, Germany
| | - Stefanie Schreiber
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, 39120, Germany; Clinic for Neurology, Otto-von-Guericke University Magdeburg, 39120, Germany
| | - Oliver Speck
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, 39120, Germany; Leibniz Institute for Neurobiology (LIN), Otto-von-Guericke University Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS) Magdeburg, Magdeburg, 39120, Germany; Department Biomedical Magnetic Resonance (BMMR), Otto-von-Guericke University Magdeburg, Germany; Research Campus STIMULATE, Otto von Guericke University, Magdeburg, Germany
| | - Christoph Reichert
- Leibniz Institute for Neurobiology (LIN), Otto-von-Guericke University Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS) Magdeburg, Magdeburg, 39120, Germany; Research Campus STIMULATE, Otto von Guericke University, Magdeburg, Germany
| | - Esther Kuehn
- Institute for Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, 39120, Germany; German Center for Neurodegenerative Diseases (DZNE), Magdeburg, 39120, Germany; Center for Behavioral Brain Sciences (CBBS) Magdeburg, Magdeburg, 39120, Germany; Hertie Institute for Clinical Brain Research, 72076 Tübingen, Germany
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3
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Villafane Barraza V, Voegtle A, de Matos Mansur B, Reichert C, Nasuto SJ, Sweeney-Reed CM. Parietal cortical alpha/beta suppression during prospective memory retrieval. Cereb Cortex 2023; 33:11235-11246. [PMID: 37804246 DOI: 10.1093/cercor/bhad359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/07/2023] [Accepted: 09/08/2023] [Indexed: 10/09/2023] Open
Abstract
Prospective memory (PM) impairment is among the most frequent memory complaints, yet little is known about the underlying neural mechanisms. PM for a planned intention may be achieved through strategic monitoring of the environment for cues, involving ongoing attentional processes, or through spontaneous retrieval. We hypothesized that parietal spectral power modulation accompanies prospectively encoded intention retrieval, irrespective of PM retrieval approach. A cognitively engaging arithmetic-based ongoing task (OGT) was employed to encourage spontaneous retrieval, with a focal, internally generated PM cue to eliminate OGT/PM trial differentiation based on perceptual or conceptual PM cue features. Two PM repetition frequencies were used to vary the extent of strategic monitoring. We observed a transient parietal alpha/beta spectral power reduction directly preceding the response, which was distinguishable on a single trial basis, as revealed by an OGT/PM trial classification rate exceeding 70% using linear discriminant analysis. The alpha/beta idling rhythm reflects cortical inhibition. A disengagement of task-relevant neural assemblies from this rhythm, reflected in alpha/beta power reduction, is deemed to increase information content, facilitate information integration, and enable engagement of neural assemblies in task-related cortical networks. The observed power reduction is consistent with the Dual Pathways model, where PM strategies converge at the PM retrieval stage.
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Affiliation(s)
- Viviana Villafane Barraza
- Neurocybernetics and Rehabilitation, Department of Neurology, Otto von Guericke University, Magdeburg, Germany
| | - Angela Voegtle
- Neurocybernetics and Rehabilitation, Department of Neurology, Otto von Guericke University, Magdeburg, Germany
| | - Bruno de Matos Mansur
- Neurocybernetics and Rehabilitation, Department of Neurology, Otto von Guericke University, Magdeburg, Germany
| | - Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Slawomir J Nasuto
- Biomedical Sciences and Biomedical Engineering Division, School of Biological Sciences, University of Reading, Reading, United Kingdom
| | - Catherine M Sweeney-Reed
- Neurocybernetics and Rehabilitation, Department of Neurology, Otto von Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany
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4
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Voegtle A, Reichert C, Hinrichs H, Sweeney-Reed CM. Repetitive Anodal TDCS to the Frontal Cortex Increases the P300 during Working Memory Processing. Brain Sci 2022; 12:1545. [PMID: 36421869 PMCID: PMC9688092 DOI: 10.3390/brainsci12111545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/05/2022] [Accepted: 11/07/2022] [Indexed: 10/17/2023] Open
Abstract
Transcranial direct current stimulation (TDCS) is a technique with which neuronal activity, and therefore potentially behavior, is modulated by applying weak electrical currents to the scalp. Application of TDCS to enhance working memory (WM) has shown promising but also contradictory results, and little emphasis has been placed on repeated stimulation protocols, in which effects are expected to be increased. We aimed to characterize potential behavioral and electrophysiological changes induced by TDCS during WM training and evaluate whether repetitive anodal TDCS has a greater modulatory impact on the processes underpinning WM than single-session stimulation. We examined the effects of single-session and repetitive anodal TDCS to the dorsolateral prefrontal cortex (DLPFC), targeting the frontal-parietal network, during a WM task in 20 healthy participants. TDCS had no significant impact on behavioral measures, including reaction time and accuracy. Analyzing the electrophysiological response, the P300 amplitude significantly increased following repetitive anodal TDCS, however, positively correlating with task performance. P300 changes were identified over the parietal cortex, which is known to engage with the frontal cortex during WM processing. These findings support the hypothesis that repetitive anodal TDCS modulates electrophysiological processes underlying WM.
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Affiliation(s)
- Angela Voegtle
- Neurocybernetics and Rehabilitation, Department of Neurology, Otto von Guericke University, 39120 Magdeburg, Germany
| | - Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, 39118 Magdeburg, Germany
- Center for Behavioral Brain Sciences—CBBS, Otto von Guericke University, 39106 Magdeburg, Germany
| | - Hermann Hinrichs
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, 39118 Magdeburg, Germany
- Center for Behavioral Brain Sciences—CBBS, Otto von Guericke University, 39106 Magdeburg, Germany
- Department of Neurology, Otto von Guericke University, 39120 Magdeburg, Germany
| | - Catherine M. Sweeney-Reed
- Neurocybernetics and Rehabilitation, Department of Neurology, Otto von Guericke University, 39120 Magdeburg, Germany
- Center for Behavioral Brain Sciences—CBBS, Otto von Guericke University, 39106 Magdeburg, Germany
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5
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Eckert D, Reichert C, Bien CG, Heinze HJ, Knight RT, Deouell LY, Dürschmid S. Distinct interacting cortical networks for stimulus-response and repetition-suppression. Commun Biol 2022; 5:909. [PMID: 36064744 PMCID: PMC9445181 DOI: 10.1038/s42003-022-03861-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 08/19/2022] [Indexed: 11/29/2022] Open
Abstract
Non-invasive studies consider the initial neural stimulus response (SR) and repetition suppression (RS) - the decreased response to repeated sensory stimuli - as engaging the same neurons. That is, RS is a suppression of the SR. We challenge this conjecture using electrocorticographic (ECoG) recordings with high spatial resolution in ten patients listening to task-irrelevant trains of auditory stimuli. SR and RS were indexed by high-frequency activity (HFA) across temporal, parietal, and frontal cortices. HFASR and HFARS were temporally and spatially distinct, with HFARS emerging later than HFASR and showing only a limited spatial intersection with HFASR: most HFASR sites did not demonstrate HFARS, and HFARS was found where no HFASR could be recorded. β activity was enhanced in HFARS compared to HFASR cortical sites. θ activity was enhanced in HFASR compared to HFARS sites. Furthermore, HFASR sites propagated information to HFARS sites via transient θ:β phase-phase coupling. In contrast to predictive coding (PC) accounts our results indicate that HFASR and HFARS are functionally linked but have minimal spatial overlap. HFASR might enable stable and rapid perception of environmental stimuli across extended temporal intervals. In contrast HFARS might support efficient generation of an internal model based on stimulus history.
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Affiliation(s)
- David Eckert
- Department of Neurology, Otto-von-Guericke University of Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39120, Magdeburg, Germany
| | - Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39120, Magdeburg, Germany
| | - Christian G Bien
- Department. of Epileptology, Krankenhaus Mara, Bielefeld University, Maraweg 21, 33617, Bielefeld, Germany
| | - Hans-Jochen Heinze
- Department of Neurology, Otto-von-Guericke University of Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39120, Magdeburg, Germany
- Forschungscampus STIMULATE, Otto-von-Guericke University of Magdeburg, Universitätsplatz 2, 39106, Magdeburg, Germany
- CBBS - center of behavioral brain sciences, Otto-von-Guericke University of Magdeburg, Universitätsplatz 2, 39106, Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE), Leipziger Str. 44, 39120, Magdeburg, Germany
| | - Robert T Knight
- Department of Psychology, University of California Berkeley, 130 Barker Hall, Berkeley, 94720, CA, USA
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, 94720, CA, USA
| | - Leon Y Deouell
- Department of Psychology and Edmond and Lily Safra Center for brain sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Stefan Dürschmid
- Department of Neurology, Otto-von-Guericke University of Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany.
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39120, Magdeburg, Germany.
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Porschewski IS, Körner M, Reichert C, Roßberg U, Seyfang B, Krum S, Baier-Welt C, Mitra A. Teaching Digitalization in Chemical Engineering at a Small‐Sized UAS. CHEM-ING-TECH 2022. [DOI: 10.1002/cite.202255135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- I.-S. Porschewski
- University of Applied Sciences Bingen Life Sciences and Engineering Berlinstr. 109 55411 Bingen Germany
| | - M. Körner
- University of Applied Sciences Bingen Technik, Informatik und Wirtschaft Berlinstr. 109 55411 Bingen Germany
| | - C. Reichert
- University of Applied Sciences Bingen Life Sciences and Engineering Berlinstr. 109 55411 Bingen Germany
| | - U. Roßberg
- University of Applied Sciences Bingen Life Sciences and Engineering Berlinstr. 109 55411 Bingen Germany
| | - B. Seyfang
- University of Applied Sciences Bingen Life Sciences and Engineering Berlinstr. 109 55411 Bingen Germany
| | - S. Krum
- University of Applied Sciences Bingen Life Sciences and Engineering Berlinstr. 109 55411 Bingen Germany
| | - C. Baier-Welt
- University of Applied Sciences Bingen Technik, Informatik und Wirtschaft Berlinstr. 109 55411 Bingen Germany
| | - A. Mitra
- University of Applied Sciences Bingen Technik, Informatik und Wirtschaft Berlinstr. 109 55411 Bingen Germany
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7
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Reichert C, Klemm L, Mushunuri RV, Kalyani A, Schreiber S, Kuehn E, Azañón E. Discriminating Free Hand Movements Using Support Vector Machine and Recurrent Neural Network Algorithms. Sensors (Basel) 2022; 22:6101. [PMID: 36015862 PMCID: PMC9412700 DOI: 10.3390/s22166101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/29/2022] [Accepted: 08/08/2022] [Indexed: 06/15/2023]
Abstract
Decoding natural hand movements is of interest for human-computer interaction and may constitute a helpful tool in the diagnosis of motor diseases and rehabilitation monitoring. However, the accurate measurement of complex hand movements and the decoding of dynamic movement data remains challenging. Here, we introduce two algorithms, one based on support vector machine (SVM) classification combined with dynamic time warping, and the other based on a long short-term memory (LSTM) neural network, which were designed to discriminate small differences in defined sequences of hand movements. We recorded hand movement data from 17 younger and 17 older adults using an exoskeletal data glove while they were performing six different movement tasks. Accuracy rates in decoding the different movement types were similarly high for SVM and LSTM in across-subject classification, but, for within-subject classification, SVM outperformed LSTM. The SVM-based approach, therefore, appears particularly promising for the development of movement decoding tools, in particular if the goal is to generalize across age groups, for example for detecting specific motor disorders or tracking their progress over time.
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Affiliation(s)
- Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Universitaetsplatz 2, 39106 Magdeburg, Germany
- Forschungscampus STIMULATE, Otto-Hahn-Str. 2, 39106 Magdeburg, Germany
| | - Lisa Klemm
- Department of Neurology, University Medical Center, Leipziger Str. 44, 39120 Magdeburg, Germany
| | | | - Avinash Kalyani
- Institute for Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE), Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Stefanie Schreiber
- Center for Behavioral Brain Sciences (CBBS), Universitaetsplatz 2, 39106 Magdeburg, Germany
- Department of Neurology, University Medical Center, Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Esther Kuehn
- Center for Behavioral Brain Sciences (CBBS), Universitaetsplatz 2, 39106 Magdeburg, Germany
- Institute for Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE), Leipziger Str. 44, 39120 Magdeburg, Germany
- Hertie Institute for Clinical Brain Research (HIH), Otfried Mueller-Str. 27, 72076 Tuebingen, Germany
| | - Elena Azañón
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Universitaetsplatz 2, 39106 Magdeburg, Germany
- Department of Neurology, University Medical Center, Leipziger Str. 44, 39120 Magdeburg, Germany
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Wienke C, Bartsch MV, Vogelgesang L, Reichert C, Hinrichs H, Heinze HJ, Dürschmid S. Mind-wandering Is Accompanied by Both Local Sleep and Enhanced Processes of Spatial Attention Allocation. Cereb Cortex Commun 2021; 2:tgab001. [PMID: 34296151 PMCID: PMC8153027 DOI: 10.1093/texcom/tgab001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 12/28/2020] [Accepted: 12/30/2020] [Indexed: 11/30/2022] Open
Abstract
Mind-wandering (MW) is a subjective, cognitive phenomenon, in which thoughts move away from the task toward an internal train of thoughts, possibly during phases of neuronal sleep-like activity (local sleep, LS). MW decreases cortical processing of external stimuli and is assumed to decouple attention from the external world. Here, we directly tested how indicators of LS, cortical processing, and attentional selection change in a pop-out visual search task during phases of MW. Participants’ brain activity was recorded using magnetoencephalography, MW was assessed via self-report using randomly interspersed probes. As expected, the performance decreased under MW. Consistent with the occurrence of LS, MW was accompanied by a decrease in high-frequency activity (HFA, 80–150 Hz) and an increase in slow wave activity (SWA, 1–6 Hz). In contrast, visual attentional selection as indexed by the N2pc component was enhanced during MW with the N2pc amplitude being directly linked to participants’ performance. This observation clearly contradicts accounts of attentional decoupling that would predict a decrease in attention-related responses to external stimuli during MW. Together, our results suggest that MW occurs during phases of LS with processes of attentional target selection being upregulated, potentially to compensate for the mental distraction during MW.
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Affiliation(s)
- Christian Wienke
- Department of Neurology, Otto-von-Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Mandy V Bartsch
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany
| | - Lena Vogelgesang
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany
| | - Christoph Reichert
- Forschungscampus STIMULATE, Otto-von-Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany.,Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany.,CBBS - center of behavioral brain sciences, Otto-von-Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany
| | - Hermann Hinrichs
- Department of Neurology, Otto-von-Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany.,Forschungscampus STIMULATE, Otto-von-Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany.,Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany.,CBBS - center of behavioral brain sciences, Otto-von-Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Hans-Jochen Heinze
- Department of Neurology, Otto-von-Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany.,Forschungscampus STIMULATE, Otto-von-Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany.,Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany.,CBBS - center of behavioral brain sciences, Otto-von-Guericke University, Universitätsplatz 2, 39106 Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Leipziger Str. 44, 39120 Magdeburg, Germany
| | - Stefan Dürschmid
- Department of Neurology, Otto-von-Guericke University, Leipziger Str. 44, 39120 Magdeburg, Germany.,Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118 Magdeburg, Germany
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9
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Frias Cortez MA, Bourauel C, Reichert C, Jäger A, Reimann S. Numerical and biomechanical analysis of orthodontic treatment of recovered periodontally compromised patients. J Orofac Orthop 2021; 83:255-268. [PMID: 34269825 DOI: 10.1007/s00056-021-00324-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 05/01/2021] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Generate a finite element (FE) model to simulate space closure and retraction mechanics for anterior maxillary teeth in periodontally compromised dentition, and compare the biomechanical effect of initial force systems with varying magnitude. MATERIALS AND METHODS The geometry of an idealized finite element model (FEM) of a maxilla was adapted such that the teeth showed reduced periodontal support together with extruded and flared incisors. In a first step, leveling and alignment of the front teeth were simulated. In a second step, force systems for orthodontic space closure of residual spaces on both sides distal to the lateral incisors were simulated. A combined intrusion and retraction cantilever was modeled, to simulate en masse retraction mechanics with segmented arches and elastic chains. A commercial FE system was used for all model generations and simulations. RESULTS Results of the simulations indicated that a force of 1.0 N is too high for space closure of flared front teeth in periodontally damaged dentition, as extreme strains may occur. En masse retraction using cantilever mechanics with lower forces showed a uniform intrusion and retraction movement and thus proved to be a better option for treating patients with a periodontally compromised dentition. CONCLUSION The outcome of this study indicates that increased periodontal stresses resulting from severe attachment loss should be seriously considered by careful planning of the orthodontic mechanics and reduction of the applied forces is suggested. The presented cantilever mechanics seems to be an appropriate means for en masse retraction of periodontally compromised extruded front teeth.
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Affiliation(s)
| | | | | | - Andreas Jäger
- Department of Orthodontics, University of Bonn, Bonn, Germany
| | - Susanne Reimann
- Oral Technology, University of Bonn, Bonn, Germany. .,Medical Engineering, University of Applied Sciences Bremerhaven, An der Karlstadt 8, 27568, Bremerhaven, Germany.
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Reichert C, Tellez Ceja IF, Sweeney-Reed CM, Heinze HJ, Hinrichs H, Dürschmid S. Impact of Stimulus Features on the Performance of a Gaze-Independent Brain-Computer Interface Based on Covert Spatial Attention Shifts. Front Neurosci 2020; 14:591777. [PMID: 33335470 PMCID: PMC7736242 DOI: 10.3389/fnins.2020.591777] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 11/10/2020] [Indexed: 11/18/2022] Open
Abstract
Regaining communication abilities in patients who are unable to speak or move is one of the main goals in decoding brain waves for brain-computer interface (BCI) control. Many BCI approaches designed for communication rely on attention to visual stimuli, commonly applying an oddball paradigm, and require both eye movements and adequate visual acuity. These abilities may, however, be absent in patients who depend on BCI communication. We have therefore developed a response-based communication BCI, which is independent of gaze shifts but utilizes covert shifts of attention to the left or right visual field. We recorded the electroencephalogram (EEG) from 29 channels and coregistered the vertical and horizontal electrooculogram. Data-driven decoding of small attention-based differences between the hemispheres, also known as N2pc, was performed using 14 posterior channels, which are expected to reflect correlates of visual spatial attention. Eighteen healthy participants responded to 120 statements by covertly directing attention to one of two colored symbols (green and red crosses for "yes" and "no," respectively), presented in the user's left and right visual field, respectively, while maintaining central gaze fixation. On average across participants, 88.5% (std: 7.8%) of responses were correctly decoded online. In order to investigate the potential influence of stimulus features on accuracy, we presented the symbols with different visual angles, by altering symbol size and eccentricity. The offline analysis revealed that stimulus features have a minimal impact on the controllability of the BCI. Hence, we show with our novel approach that spatial attention to a colored symbol is a robust method with which to control a BCI, which has the potential to support severely paralyzed people with impaired eye movements and low visual acuity in communicating with their environment.
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Affiliation(s)
- Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Magdeburg, Germany
- Research Campus STIMULATE, Magdeburg, Germany
| | | | - Catherine M. Sweeney-Reed
- Center for Behavioral Brain Sciences, Magdeburg, Germany
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
| | - Hans-Jochen Heinze
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Magdeburg, Germany
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
| | - Hermann Hinrichs
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Magdeburg, Germany
- Research Campus STIMULATE, Magdeburg, Germany
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
| | - Stefan Dürschmid
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
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11
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Dürschmid S, Reichert C, Hinrichs H, Heinze HJ, Kirsch HE, Knight RT, Deouell LY. Direct Evidence for Prediction Signals in Frontal Cortex Independent of Prediction Error. Cereb Cortex 2020; 29:4530-4538. [PMID: 30590422 DOI: 10.1093/cercor/bhy331] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/27/2018] [Accepted: 11/29/2018] [Indexed: 12/13/2022] Open
Abstract
Predictive coding (PC) has been suggested as one of the main mechanisms used by brains to interact with complex environments. PC theories posit top-down prediction signals, which are compared with actual outcomes, yielding in turn prediction error (PE) signals, which are used, bottom-up, to modify the ensuing predictions. However, disentangling prediction from PE signals has been challenging. Critically, while many studies found indirect evidence for PC in the form of PE signals, direct evidence for the prediction signal is mostly lacking. Here, we provide clear evidence, obtained from intracranial cortical recordings in human surgical patients, that the human lateral prefrontal cortex evinces prediction signals while anticipating an event. Patients listened to task-irrelevant sequences of repetitive tones including infrequent predictable or unpredictable pitch deviants. The broadband high-frequency amplitude (HFA) was decreased prior to the onset of expected relative to unexpected deviants in the frontal cortex only, and its amplitude was sensitive to the increasing likelihood of deviants following longer trains of standards in the unpredictable condition. Single-trial HFA predicted deviations and correlated with poststimulus response to deviations. These results provide direct evidence for frontal cortex prediction signals independent of PE signals.
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Affiliation(s)
- Stefan Dürschmid
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg, Germany
| | - Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, Magdeburg, Germany.,CBBS-Center of Behavioral Brain Sciences, Otto-von-Guericke University, Universitätsplatz 2, Magdeburg, Germany
| | - Hermann Hinrichs
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg, Germany.,Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Leipziger Str. 44, Magdeburg, Germany.,Forschungscampus STIMULATE, Otto-von-Guericke University, Universitätsplatz 2, Magdeburg, Germany.,CBBS-Center of Behavioral Brain Sciences, Otto-von-Guericke University, Universitätsplatz 2, Magdeburg, Germany
| | - Hans-Jochen Heinze
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg, Germany.,Stereotactic Neurosurgery, Otto-von-Guericke University, Leipziger Str. 44, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Leipziger Str. 44, Magdeburg, Germany.,Forschungscampus STIMULATE, Otto-von-Guericke University, Universitätsplatz 2, Magdeburg, Germany.,CBBS-Center of Behavioral Brain Sciences, Otto-von-Guericke University, Universitätsplatz 2, Magdeburg, Germany
| | - Heidi E Kirsch
- Department of Neurology, University of California, 400 Parnassus Avenue, San Francisco, CA, USA
| | - Robert T Knight
- Helen Wills Neuroscience Institute and Department of Psychology, University of California, Berkeley, CA, USA
| | - Leon Y Deouell
- Edmond and Lily Safra Center for Brain Sciences and Department of Psychology, The Hebrew University of Jerusalem, Mount Scopus, Jerusalem, Israel
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12
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Reichert C, Dürschmid S, Bartsch MV, Hopf JM, Heinze HJ, Hinrichs H. Decoding the covert shift of spatial attention from electroencephalographic signals permits reliable control of a brain-computer interface. J Neural Eng 2020; 17:056012. [PMID: 32906103 DOI: 10.1088/1741-2552/abb692] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE One of the main goals of brain-computer interfaces (BCI) is to restore communication abilities in patients. BCIs often use event-related potentials (ERPs) like the P300 which signals the presence of a target in a stream of stimuli. The P300 and related approaches, however, are inherently limited, as they require many stimulus presentations to obtain a usable control signal. Many approaches depend on gaze direction to focus the target, which is also not a viable approach in many cases, because eye movements might be impaired in potential users. Here we report on a BCI that avoids both shortcomings by decoding spatial target information, independent of gaze shifts. APPROACH We present a new method to decode from the electroencephalogram (EEG) covert shifts of attention to one out of four targets simultaneously presented in the left and right visual field. The task is designed to evoke the N2pc component-a hemisphere lateralized response, elicited over the occipital scalp contralateral to the attended target. The decoding approach involves decoding of the N2pc based on data-driven estimation of spatial filters and a correlation measure. MAIN RESULTS Despite variability of decoding performance across subjects, 22 out of 24 subjects performed well above chance level. Six subjects even exceeded 80% (cross-validated: 89%) correct predictions in a four-class discrimination task. Hence, the single-trial N2pc proves to be a component that allows for reliable BCI control. An offline analysis of the EEG data with respect to their dependence on stimulation time and number of classes demonstrates that the present method is also a workable approach for two-class tasks. SIGNIFICANCE Our method extends the range of strategies for gaze-independent BCI control. The proposed decoding approach has the potential to be efficient in similar applications intended to decode ERPs.
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Affiliation(s)
- Christoph Reichert
- Leibniz Institute for Neurobiology, Magdeburg, Germany. Forschungscampus STIMULATE, Magdeburg, Germany. Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
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13
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Vogelgesang L, Reichert C, Hinrichs H, Heinze HJ, Dürschmid S. Early Shift of Attention Is Not Regulated by Mind Wandering in Visual Search. Front Neurosci 2020; 14:552637. [PMID: 33117116 PMCID: PMC7561678 DOI: 10.3389/fnins.2020.552637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 09/07/2020] [Indexed: 11/13/2022] Open
Abstract
Unique to humans is the ability to report subjective awareness of a broad repertoire of external and internal events. Even when asked to focus on external information, the human’s mind repeatedly wanders to task-unrelated thoughts, which limits reading comprehension or the ability to withhold automated manual responses. This led to the attentional decoupling account of mind wandering (MW). However, manual responses are not an ideal parameter to study attentional decoupling, given that during MW, the online adjustment of manual motor responses is impaired. Hence, whether early attentional mechanisms are indeed downregulated during MW or only motor responses being slowed is not clear. In contrast to manual motor responses, eye movements are considered a sensitive proxy of attentional shifts. Using a simple target detection task, we asked subjects to indicate whether a target was presented within a visual search display by pressing a button while we recorded eye movements and unpredictably asked the subjects to rate their actual level of MW. Generally, manual reaction times increased with MW, both in target absent and present trials. But importantly, even in trials with MW, subjects detected earlier a presented than an absent target. The decoupling account would predict more fixations of the target before pressing the button during MW. However, our results did not corroborate this assumption. Most importantly, subject’s time to direct gaze at the target was equally fast in trials with and without MW. Our results corroborate our hypothesis that during MW early, bottom–up driven attentional processes are not decoupled but selectively manual motor responses are slowed.
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Affiliation(s)
- Lena Vogelgesang
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Forschungscampus STIMULATE, Otto-von-Guericke University, Magdeburg, Germany
- CBBS – Center of Behavioral Brain Sciences, Otto-von-Guericke University, Magdeburg, Germany
| | - Hermann Hinrichs
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Forschungscampus STIMULATE, Otto-von-Guericke University, Magdeburg, Germany
- CBBS – Center of Behavioral Brain Sciences, Otto-von-Guericke University, Magdeburg, Germany
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Hans-Jochen Heinze
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Forschungscampus STIMULATE, Otto-von-Guericke University, Magdeburg, Germany
- CBBS – Center of Behavioral Brain Sciences, Otto-von-Guericke University, Magdeburg, Germany
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Stefan Dürschmid
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
- *Correspondence: Stefan Dürschmid, ;
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14
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Krueger J, Reichert C, Dürschmid S, Krauth R, Vogt S, Huchtemann T, Lindquist S, Lamprecht J, Sailer M, Heinze HJ, Hinrichs H, Sweeney-Reed CM. Rehabilitation nach Schlaganfall: Durch Gehirn-Computer-Schnittstelle
vermittelte funktionelle Elektrostimulation. KLIN NEUROPHYSIOL 2020. [DOI: 10.1055/a-1205-7467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
ZusammenfassungEine Gehirn-Computer-Schnittstelle (BCI) in der Rehabilitation von
Schlaganfallpatienten ermöglicht die Steuerung einer funktionellen
Elektrostimulation (FES), um eine Muskelkontraktion in der gelähmten
Extremität zum Zeitpunkt der Bewegungsintention durch Erkennung
entsprechender Hirnsignale auszulösen. Es wird angenommen, dass eine
genaue zeitliche Kohärenz zwischen Bewegungsintention und visuellem
sowie propriozeptivem Feedback, ausgelöst durch eine reale Bewegung,
neuroplastische Prozesse begünstigen und eine funktionelle
Verbesserung der Parese bewirken kann. In dieser systematischen
Übersichtsarbeit zu randomisierten kontrollierten Studien wurden die
Datenbanken Pubmed, Scopus und Web of Science durchsucht und von 516
berücksichtigten Publikationen 13 ausgewählt, die auf 7
Studienpopulationen basierten. Ein direkter Vergleich der Studien ist durch
Unterschiede im Studiendesign erschwert. Fünf Studien berichten von
einer verbesserten motorischen Funktion in der BCI-FES-Gruppe, davon zeigen
3 signifikante Unterschiede zwischen der BCI-FES- und der
Kontrollgruppe.
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Affiliation(s)
- Johanna Krueger
- Neurokybernetik und Rehabilitation, Klinik für Neurologie,
Otto-von-Guericke Universität, Magdeburg
- Krankenhaus Barmherziger Brüder Regensburg
| | - Christoph Reichert
- Abteilung Verhaltensneurologie, Leibniz Institut für
Neurobiologie (LIN), Magdeburg
| | - Stefan Dürschmid
- Abteilung Verhaltensneurologie, Leibniz Institut für
Neurobiologie (LIN), Magdeburg
| | - Richard Krauth
- Neurokybernetik und Rehabilitation, Klinik für Neurologie,
Otto-von-Guericke Universität, Magdeburg
| | - Susanne Vogt
- Klinik für Neurologie, Otto-von-Guericke Universität,
Magdeburg
| | | | | | - Juliane Lamprecht
- MEDIAN Klinik NRZ Magdeburg, MEDIAN Klinik Flechtingen
- An-Institut für Neurorehabilitation, Otto-von-Guericke
Universität, Magdeburg
| | - Michael Sailer
- MEDIAN Klinik NRZ Magdeburg, MEDIAN Klinik Flechtingen
- An-Institut für Neurorehabilitation, Otto-von-Guericke
Universität, Magdeburg
| | - Hans-Jochen Heinze
- Abteilung Verhaltensneurologie, Leibniz Institut für
Neurobiologie (LIN), Magdeburg
- Klinik für Neurologie, Otto-von-Guericke Universität,
Magdeburg
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE),
Magdeburg
| | - Hermann Hinrichs
- Abteilung Verhaltensneurologie, Leibniz Institut für
Neurobiologie (LIN), Magdeburg
- Klinik für Neurologie, Otto-von-Guericke Universität,
Magdeburg
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE),
Magdeburg
- Center for Behavioral Brain Sciences (CBBS), Magdeburg
- Forschungscampus STIMULATE, Magdeburg
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15
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Widmer N, Abbet C, Brunner J, Faro Barros J, Ullmann S, Beeler C, Hug B, Reichert C, Bättig VAD, Caglioti G, Flück M, Moll H, Herklotz R. Swiss Armed Forces deployment during the COVID-19 pandemic: militia pharmacy officers' roles and duties. BMJ Mil Health 2020; 167:141. [PMID: 32948664 DOI: 10.1136/bmjmilitary-2020-001605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/19/2020] [Accepted: 08/28/2020] [Indexed: 11/04/2022]
Affiliation(s)
- Nicolas Widmer
- Logistics Training Unit, Swiss Armed Forces, Thun, Switzerland .,Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva, Switzerland
| | - C Abbet
- 1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
| | - J Brunner
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva, Switzerland.,1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
| | - J Faro Barros
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, Geneva, Switzerland.,1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
| | - S Ullmann
- 1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
| | - C Beeler
- 1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
| | - B Hug
- 1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
| | - C Reichert
- 1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
| | - V A D Bättig
- 1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
| | - G Caglioti
- 1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
| | - M Flück
- Swiss Armed Forces Pharmacy, Swiss Armed Forces, Ittigen b. Bern, Switzerland.,Staff of the Surgeon General, Swiss Armed Forces, Ittigen b. Bern, Switzerland
| | - H Moll
- Staff of the Surgeon General, Swiss Armed Forces, Ittigen b. Bern, Switzerland
| | - R Herklotz
- 1st Logistic Brigade, Swiss Armed Forces, Bern, Switzerland
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16
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Reichert C, Dürschmid S, Hinrichs H. EEG als Steuersignal: Gehirnaktivität entschlüsseln
und effizient als Kommunikationsmittel für Patienten mit motorischen
Defiziten nutzen. KLIN NEUROPHYSIOL 2020. [DOI: 10.1055/a-1135-3782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Zusammenfassung
Ziel der Studie Ereignis-korrelierte Potenziale werden in der Regel in
einzelnen EEG-Kanälen ermittelt. Mit einem einzelnen Kanal wird jedoch
nur ein Teil des gesamten Hirnprozesses erfasst. Für eine
Gehirn-Computer Schnittstelle, die in kurzer Zeit eine Entscheidung treffen
muss, ist diese singuläre Gehirnantwort häufig unzureichend
wogegen die Information aus mehreren Kanälen häufig redundant
ist. Beide Vorgehensweisen sind nicht optimal. Daher ist es unser Ziel, die
Kanäle zu wenigen Komponenten zu kombinieren, die die relevantesten
Modulationen eines Hirnprozesses erfassen.
Methodik Wir nutzen die kanonische Korrelationsanalyse, um datengetrieben
räumliche Filter aus dem EEG zu bestimmen. Mit der Produkt-Moment
Korrelation ermitteln wir, auf welche von 12 verschiedenen Stimulussequenzen die
Studienteilnehmer geachtet haben.
Ergebnisse Die verdeckte Aufmerksamkeit der Studienteilnehmer konnte mit
hoher Genauigkeit (89,3±9,2%) aus dem räumlich
gefilterten EEG und signifikant besser als aus einzelnen Kanälen
dekodiert werden.
Schlussfolgerung Die aus dem EEG erlernten räumlichen Filter
ermöglichen die Extraktion von Komponenten, die einen event-korrelierten
Gehirnprozess charakterisieren und eine Gehirn-Computer Schnittstelle effektiv
steuern können, was von hoher Relevanz für Patienten ist, die
nicht mehr anderweitig kommunizieren können.
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Affiliation(s)
- Christoph Reichert
- Abteilung Verhaltensneurologie, Leibniz-Institut für
Neurobiologie, Magdeburg
- Center for Behavioral Brain Sciences (CBBS), Magdeburg
- Forschungscampus STIMULATE, Magdeburg
| | - Stefan Dürschmid
- Abteilung Verhaltensneurologie, Leibniz-Institut für
Neurobiologie, Magdeburg
- Klinik für Neurologie, Universitätsklinikum
Magdeburg
| | - Hermann Hinrichs
- Abteilung Verhaltensneurologie, Leibniz-Institut für
Neurobiologie, Magdeburg
- Center for Behavioral Brain Sciences (CBBS), Magdeburg
- Forschungscampus STIMULATE, Magdeburg
- Klinik für Neurologie, Universitätsklinikum
Magdeburg
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17
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Dürschmid S, Reichert C, Walter N, Hinrichs H, Heinze HJ, Ohl FW, Tononi G, Deliano M. Self-regulated critical brain dynamics originate from high frequency-band activity in the MEG. PLoS One 2020; 15:e0233589. [PMID: 32525940 PMCID: PMC7289413 DOI: 10.1371/journal.pone.0233589] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 05/08/2020] [Indexed: 11/18/2022] Open
Abstract
Brain function requires the flexible coordination of billions of neurons across multiple scales. This could be achieved by scale-free, critical dynamics balanced at the edge of order and disorder. Criticality has been demonstrated in several, often reduced neurophysiological model systems. In the intact human brain criticality has yet been only verified for the resting state. A more direct link between the concept of criticality and oscillatory brain physiology, which is strongly related to cognition, is yet missing. In the present study we therefore carried out a frequency-specific analysis of criticality in the MEG, recorded while subjects were in a defined cognitive state through mindfulness meditation. In a two-step approach we assessed whether the macroscopic neural avalanche dynamics is scale-free by evaluating the goodness of a power-law fits of cascade size and duration distributions of MEG deflections in different frequency bands. In a second step we determined the closeness of the power-law exponents to a critical value of -1.5. Power-law fitting was evaluated by permutation testing, fitting of alternative distributions, and cascade shape analysis. Criticality was verified by defined relationships of exponents of cascade size and duration distributions. Behavioral relevance of criticality was tested by correlation of indices of criticality with individual scores of the Mindful Attention Awareness Scale. We found that relevant scale-free near-critical dynamics originated only from broad-band high-frequency (> 100 Hz) MEG activity, which has been associated with action potential firing, and therefore links criticality on the macroscopic level of MEG to critical spike avalanches on a microscopic level. Whereas a scale-free dynamics was found under mindfulness meditation and rest, avalanche dynamics shifted towards a critical point during meditation by reduction of neural noise. Together with our finding that during mindfulness meditation avalanches show differences in topography relative to rest, our results show that self-regulated attention as required during meditation can serve as a control parameter of criticality in scale-free brain dynamics.
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Affiliation(s)
- Stefan Dürschmid
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
| | - Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Forschungscampus STIMULATE, Otto-von-Guericke University, Magdeburg, Germany.,CBBS-center of behavioral brain sciences, Otto-von-Guericke University, Magdeburg, Germany
| | - Nike Walter
- Research Section Applied Consciousness Science, Department of Psychosomatic Medicine, University Medical Center, Regensburg, Germany
| | - Hermann Hinrichs
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,Forschungscampus STIMULATE, Otto-von-Guericke University, Magdeburg, Germany.,CBBS-center of behavioral brain sciences, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Hans-Jochen Heinze
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,Forschungscampus STIMULATE, Otto-von-Guericke University, Magdeburg, Germany.,CBBS-center of behavioral brain sciences, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Frank W Ohl
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany.,Dept. Systems Physiology of Learning (SPL), Leibniz Institute for Neurobiology (LIN), Magdeburg, Germany.,Institute of Biology (IBIO), Otto-von-Guericke University, Magdeburg, Germany
| | - Giulio Tononi
- Department of Psychiatry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America.,Center for sleep and consciousness, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Matthias Deliano
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
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18
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Grossmann L, Moll P, Reichert C, Weiss J. Influence of Energy Density on Foamability: Comparison of Three Foaming Methods. Food Res Int 2020; 129:108794. [DOI: 10.1016/j.foodres.2019.108794] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 10/22/2019] [Accepted: 10/30/2019] [Indexed: 10/25/2022]
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19
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Farahat A, Reichert C, Sweeney-Reed CM, Hinrichs H. Convolutional neural networks for decoding of covert attention focus and saliency maps for EEG feature visualization. J Neural Eng 2019; 16:066010. [PMID: 31416059 DOI: 10.1088/1741-2552/ab3bb4] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Convolutional neural networks (CNNs) have proven successful as function approximators and have therefore been used for classification problems including electroencephalography (EEG) signal decoding for brain-computer interfaces (BCI). Artificial neural networks, however, are considered black boxes, because they usually have thousands of parameters, making interpretation of their internal processes challenging. Here we systematically evaluate the use of CNNs for EEG signal decoding and investigate a method for visualizing the CNN model decision process. APPROACH We developed a CNN model to decode the covert focus of attention from EEG event-related potentials during object selection. We compared the CNN and the commonly used linear discriminant analysis (LDA) classifier performance, applied to datasets with different dimensionality, and analyzed transfer learning capacity. Moreover, we validated the impact of single model components by systematically altering the model. Furthermore, we investigated the use of saliency maps as a tool for visualizing the spatial and temporal features driving the model output. MAIN RESULTS The CNN model and the LDA classifier achieved comparable accuracy on the lower-dimensional dataset, but CNN exceeded LDA performance significantly on the higher-dimensional dataset (without hypothesis-driven preprocessing), achieving an average decoding accuracy of 90.7% (chance level = 8.3%). Parallel convolutions, tanh or ELU activation functions, and dropout regularization proved valuable for model performance, whereas the sequential convolutions, ReLU activation function, and batch normalization components reduced accuracy or yielded no significant difference. Saliency maps revealed meaningful features, displaying the typical spatial distribution and latency of the P300 component expected during this task. SIGNIFICANCE Following systematic evaluation, we provide recommendations for when and how to use CNN models in EEG decoding. Moreover, we propose a new approach for investigating the neural correlates of a cognitive task by training CNN models on raw high-dimensional EEG data and utilizing saliency maps for relevant feature extraction.
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Affiliation(s)
- Amr Farahat
- Neurocybernetics and Rehabiliation Research Group, Department of Neurology, Otto-von-Guericke University Hospital, Leipziger Str. 44, 39120 Magdeburg, Germany
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Grossmann L, Beicht M, Reichert C, Weiss J. Foaming properties of heat-aggregated microparticles from whey proteins. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.06.037] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Kasaj A, Willershausen B, Reichert C, Gortan-Kasaj A, Zafiropoulos GG, Schmidt M. Corrigendum to “Human periodontal fibroblast response to a nanostructured hydroxyapatite bone replacement graft in vitro” [Arch. Oral Biol. 53 July (7) (2008) 683–689]. Arch Oral Biol 2019; 105:88. [DOI: 10.1016/j.archoralbio.2018.11.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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Stoppenbrink D, Daratsianos N, Kutschera E, Scharf S, Braumann B, Götz W, Jäger A, Reichert C. Dimensional changes of the alveolar ridge contour of the premolar extraction site in adolescents. J Orofac Orthop 2019; 80:205-215. [PMID: 31161227 DOI: 10.1007/s00056-019-00182-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 04/29/2019] [Indexed: 11/26/2022]
Abstract
PURPOSE Premolar extraction in orthodontic therapy is common in adolescent patients. Knowledge of the tissue reaction in an extraction site is mainly based on studies with animal and adults. Thus, we aim to describe the time-dependent dimensional changes of the alveolar ridge contour of the premolar extraction site in adolescents. METHODS Clinical data were obtained from a randomized controlled clinical trial (Universal Trial Number U1111-1132-6655), comparing treatment modalities with orthodontic space closure was initiated after 2-4 weeks (group A) and ≥ 12 weeks after tooth extraction (group B). Dental casts taken before the tooth extraction (T1) and before initiation of the space closure (T2) were digitalized with a 3D scanner and superimposed to analyze the dimensional changes of the alveolar ridge in early and later stage of wound healing. Linear mixed models were used for statistical analysis. RESULTS Plaster models of 25 patients (mean age 15.2 years, 11 male and 14 female) with 66 extraction sites were enrolled. The average atrophic changes from tooth extraction to the early stage of wound healing (group A, n = 41) were in total 27.5% ± 11.8; labially 31.3% ± 15.1 and orally 23.6% ± 13.4. In group B (n = 25) the average atrophic changes were in total 38.6% ± 12.1; labially 46.2% ± 16.7; orally 31.3% ± 18.9. The atrophic changes between the groups in total (p = 0.031) and at the labial side (p = 0.012) were significant. The jaw affiliation was a significant parameter for all examined areas in regard to all cases (labial p = 0.019; oral p = 0.020; total p = 0.001). Atrophic changes between genders were not statistically different. CONCLUSIONS Alveolar atrophy increased over time after extraction primarily in the lower jaw at the labial side. The main atrophy occurred in the first healing phase of the extraction socket. Thus, timely coordination is important to preserve sufficient bone levels. The atrophic changes of the alveolar ridge in adolescents parallel those reported for adults.
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Affiliation(s)
- David Stoppenbrink
- Department of Prosthodontics, University of Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany
| | - Nikolaos Daratsianos
- Department of Orthodontics, University of Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany
| | - Eric Kutschera
- Department of Orthodontics, University of Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany
| | - Sven Scharf
- Department of Orthodontics, University of Cologne, Kerpener Straße 32, 50931, Cologne, Germany
| | - Bert Braumann
- Department of Orthodontics, University of Cologne, Kerpener Straße 32, 50931, Cologne, Germany
| | - Werner Götz
- Department of Orthodontics, University of Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany
| | - Andreas Jäger
- Department of Orthodontics, University of Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany
| | - Christoph Reichert
- Department of Orthodontics, University of Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany.
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Baghdadi D, Reimann S, Keilig L, Reichert C, Jäger A, Bourauel C. Biomechanical analysis of initial incisor crowding alignment in the periodontally reduced mandible using the finite element method. J Orofac Orthop 2019; 80:184-193. [PMID: 31139844 DOI: 10.1007/s00056-019-00179-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 04/11/2019] [Indexed: 12/20/2022]
Abstract
AIMS To reduce remaining plaque niches due to dental malocclusion after periodontal treatment and to avoid reinflammation of periodontitis, severe anterior crowding can be treated orthodontically. The treatment indication is motivated by aesthetic and functional needs. In this study the biomechanical behaviour of crowded lower front teeth in reduced periodontium is analysed. METHODS Using the finite element (FE) method, a model of the mandible was constructed with an anterior crowding of 4 mm and a vertical bone loss of 4 mm in the front tooth area. A 0.3 mm (0.012″) round superelastic nickel titanium (NiTi) arch wire was fitted to an ideal positioned teeth set-up and was inserted into the brackets of teeth 34 to 44 in the crowded model. The premolars were used as the anchorage unit. Material parameters were adopted from previous investigations, including bone (homogenous, isotropic, E = 2 GPa), teeth (E = 20 GPa) and healthy periodontal ligament (PDL, bilinear elastic; E1 = 0.05 MPa; E2 = 0.2 MPa; ε12 = 7%). All simulations were compared to simulations with a physiological periodontal model to assess the effect of bone loss at teeth 42 to 32. Additionally, the influence of three arch wire materials (nonsuperelastic NiTi, superelastic NiTi and stainless steel) were analysed in a reduced model, including only brackets in position of the crowded front teeth, wire and ligatures. Wire force levels and stresses were determined to assess the influence of material variation. RESULTS Initial tooth mobility is increased by a factor of 2.5 in case of a moderate periodontal defect. Front teeth with reduced attachment display increased strains in the periodontal ligament up to a factor of 2. Forces in the model with reduced periodontium were decreased by a factor of 2. Comparing different aligning arch wires, stainless steel appears to have the highest force and stress levels. Force levels of this alloy were 7.5 times higher than with the superelastic NiTi wire. Force levels of nonsuperelastic NiTi appeared to be 1.8 times higher than superelastic NiTi. Calculated stresses with stainless steel were 5 times higher than with the nonsuperelastic NiTi and 10 times higher than with superelastic NiTi. CONCLUSION Periodontally reduced incisors 42 to 32 are associated with an increased load on periodontal tissue and increased level of tooth mobility during fixed orthodontic treatment. This has to be considered by reducing orthodontic force levels and by selecting mechanics that reduce the load to the tissue.
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Affiliation(s)
- Dorna Baghdadi
- Oralmedizinische Technologie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany.
| | - Susanne Reimann
- Oralmedizinische Technologie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany.,Hochschule Bremerhaven, Bremerhaven, Germany
| | - Ludger Keilig
- Oralmedizinische Technologie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany.,Abteilung für Zahnärztliche Prothetik, Propädeutik und Werkstoffwissenschaften, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Christoph Reichert
- Poliklinik für Kieferorthopädie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Andreas Jäger
- Poliklinik für Kieferorthopädie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Christoph Bourauel
- Oralmedizinische Technologie, Universitätsklinikum Bonn, Rheinische Friedrich-Wilhelms-Universität Bonn, Welschnonnenstraße 17, 53111, Bonn, Germany
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Reichert C, Heinze N, Pfeiffer T, Dürschmid S, Hinrichs H. P63. Detection of error potentials from EEG and MEG recordings and its value for BMI control. Clin Neurophysiol 2018. [DOI: 10.1016/j.clinph.2018.04.698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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25
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Weibel J, Lin YS, Landolt HP, Garbazza C, Meyer M, Slawik H, Borgwardt S, Reichert C, Cajochen C. 0180 Influence of Long-Term Caffeine Consumption and Its Withdrawal on Subjective Sleepiness, Vigilance, and Melatonin. Sleep 2018. [DOI: 10.1093/sleep/zsy061.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- J Weibel
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, SWITZERL
| | - Y S Lin
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, SWITZERL
- Neuropsychiatry and Brain Imaging, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
| | - H P Landolt
- Institute of Pharmacology and Toxicology, University of Zürich, Zürich, SWITZERL
- Zürich Center for Interdisciplinary Sleep Research, University of Zürich, Zürich, SWITZERL
| | - C Garbazza
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, SWITZERL
| | - M Meyer
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, SWITZERL
- Clinical Sleep Laboratory, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
| | - H Slawik
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, SWITZERL
- Clinical Sleep Laboratory, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
| | - S Borgwardt
- Neuropsychiatry and Brain Imaging, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
| | - C Reichert
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, SWITZERL
| | - C Cajochen
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, SWITZERL
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, SWITZERL
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Dürschmid S, Reichert C, Kuhn J, Freund HJ, Hinrichs H, Heinze HJ. Deep brain stimulation of the nucleus basalis of Meynert attenuates early EEG components associated with defective sensory gating in patients with Alzheimer disease - a two-case study. Eur J Neurosci 2017; 51:1201-1209. [PMID: 29055119 DOI: 10.1111/ejn.13749] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 09/22/2017] [Accepted: 10/03/2017] [Indexed: 12/17/2022]
Abstract
Alzheimer's disease (AD) is associated with deterioration of memory and cognitive function and a degeneration of neurons of the nucleus basalis of Meynert (NBM). The NBM is the major input source of acetylcholine (ACh) to the cortex. The decreasing cholinergic innervation of the cortex due to degeneration of the NBM might be the cause of loss of memory function. NBM-Deep brain stimulation (NBM-DBS) is considered to serve as a potential therapeutic option for patients with AD by supporting residual cholinergic transmission to stabilize oscillatory activity in memory-relevant circuits. However, whether DBS could improve sensory memory functions in patients with AD is not clear. Here, in a passive auditory oddball paradigm, patients with AD (N = 2) listened to repetitive background tones (standard tones) randomly interrupted by frequency deviants in two blocks with NBM-DBS OFF and then NBM-DBS ON, while age-matched healthy controls (N = 6) repeated the experiment twice. The mismatch negativity in NBM-DBS OFF significantly differed from controls in both blocks, but not under NBM-DBS, which was likely due to a pronounced P50 increase overlapping with the N1 in NBM-DBS OFF. This early complex of EEG components recovered under stimulation to a normal level as defined by responses in controls. In this temporal interval, we found in patients with NBM-DBS ON (but not with NBM-DBS OFF) and in controls a strong repetition suppression effect to standard tones - with more attenuated responses to frequently repeated standard tones. This highlights the role of NBM-DBS for sensory gating of familiar auditory information into sensory memory.
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Affiliation(s)
- Stefan Dürschmid
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39120, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
| | - Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39120, Magdeburg, Germany
| | - Jens Kuhn
- Department of Psychiatry and Psychotherapy, Medical Faculty, University of Cologne, Cologne, Germany.,Johanniter Hospital Oberhausen, EVKLN, Oberhausen, Germany
| | | | - Hermann Hinrichs
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39120, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,Stereotactic Neurosurgery, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany.,CBBS - center of behavioral brain sciences, Otto-von-Guericke University, Magdeburg, Germany
| | - Hans-Jochen Heinze
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Brenneckestr. 6, 39120, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,Stereotactic Neurosurgery, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany.,CBBS - center of behavioral brain sciences, Otto-von-Guericke University, Magdeburg, Germany
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Reichert C, Dürschmid S, Heinze HJ, Hinrichs H. A Comparative Study on the Detection of Covert Attention in Event-Related EEG and MEG Signals to Control a BCI. Front Neurosci 2017; 11:575. [PMID: 29085279 PMCID: PMC5650628 DOI: 10.3389/fnins.2017.00575] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 10/02/2017] [Indexed: 11/25/2022] Open
Abstract
In brain-computer interface (BCI) applications the detection of neural processing as revealed by event-related potentials (ERPs) is a frequently used approach to regain communication for people unable to interact through any peripheral muscle control. However, the commonly used electroencephalography (EEG) provides signals of low signal-to-noise ratio, making the systems slow and inaccurate. As an alternative noninvasive recording technique, the magnetoencephalography (MEG) could provide more advantageous electrophysiological signals due to a higher number of sensors and the magnetic fields not being influenced by volume conduction. We investigated whether MEG provides higher accuracy in detecting event-related fields (ERFs) compared to detecting ERPs in simultaneously recorded EEG, both evoked by a covert attention task, and whether a combination of the modalities is advantageous. In our approach, a detection algorithm based on spatial filtering is used to identify ERP/ERF components in a data-driven manner. We found that MEG achieves higher decoding accuracy (DA) compared to EEG and that the combination of both further improves the performance significantly. However, MEG data showed poor performance in cross-subject classification, indicating that the algorithm's ability for transfer learning across subjects is better in EEG. Here we show that BCI control by covert attention is feasible with EEG and MEG using a data-driven spatial filter approach with a clear advantage of the MEG regarding DA but with a better transfer learning in EEG.
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Affiliation(s)
- Christoph Reichert
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Stefan Dürschmid
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
| | - Hans-Jochen Heinze
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany
| | - Hermann Hinrichs
- Department of Behavioral Neurology, Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany
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Reichert C, Kutschera E, Plötz C, Scharf S, Gölz L, Fimmers R, Fuhrmann C, Wahl G, Braumann B, Jäger A. Incidence and severity of gingival invaginations associated with early versus late initiation of orthodontic space closure after tooth extraction : A multicenter pilot and randomized controlled trial. J Orofac Orthop 2017; 78:415-425. [PMID: 28660421 DOI: 10.1007/s00056-017-0098-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 09/15/2016] [Indexed: 12/01/2022]
Abstract
OBJECTIVE Gingival invaginations are a common side effect of orthodontic extraction-space closure. The timing of initiating the closure of an extraction space varies greatly in clinical practice. In this multicenter pilot and randomized controlled trial, we prospectively investigated whether initiating space closure in the early stage of wound healing would benefit the incidence and severity of invaginations developing in the extraction sites. METHODS A total of 368 patients were screened for indications to extract at least one mandibular premolar. Those recruited were randomly assigned to one of two treatment arms: initiation of space closure either 2-4 weeks (arm A) or ≥12 weeks (arm B) after tooth extraction. Clinical data regarding treatment process and periodontal tissue response were recorded during and after space closure and analyzed by a specialized biometrics unit. The study was performed under continuous surveillance by an independent study control center. RESULTS A total of 74 extraction sites were analyzed. Regarding the incidence of gingival invaginations, there were no significant intergroup differences [p = 0.13; group A comprising 37/44 (84.1%) and group B 29/30 (96.7%) invaginated sites]. The same was true based on either maxillary (p = 0.52) or mandibular (p = 0.21) sites only, and the severity of the invaginations did not differ between the treatment arms. CONCLUSIONS As to the incidence and severity of gingival invaginations, we did not notice any statistically significant differences between the two timeframes. Our data do, however, provide a basis to identify additional confounders and to improve the accuracy of case-load estimations for future trials.
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Affiliation(s)
- Christoph Reichert
- Department of Orthodontics, Rheinische Friedrich-Wilhelms University of Bonn, Bonn, Germany. .,Department of Orthodontics, University Hospital Bonn, Welschnonnenstrasse 17, 53111, Bonn, Germany.
| | - Eric Kutschera
- Department of Orthodontics, Rheinische Friedrich-Wilhelms University of Bonn, Bonn, Germany
| | - Christina Plötz
- Department of Orthodontics, Rheinische Friedrich-Wilhelms University of Bonn, Bonn, Germany
| | - Sven Scharf
- Department of Orthodontics, University Hospital Cologne, Cologne, Germany
| | - Lina Gölz
- Department of Orthodontics, Rheinische Friedrich-Wilhelms University of Bonn, Bonn, Germany
| | - Rolf Fimmers
- Institute of Medical Biometry, Informatics and Epidemiology, University Hospital Bonn, Bonn, Germany
| | | | - Gerhard Wahl
- Department of Oral Surgery, Rheinische Friedrich-Wilhelms University of Bonn, Bonn, Germany
| | - Bert Braumann
- Department of Orthodontics, University Hospital Cologne, Cologne, Germany
| | - Andreas Jäger
- Department of Orthodontics, Rheinische Friedrich-Wilhelms University of Bonn, Bonn, Germany
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Bouma BJ, Riezenbos R, Voogel AJ, Veldhorst MH, Jaarsma W, Hrudova J, Cernohorsky B, Chamuleau S, van den Brink RBA, Breedveld R, Reichert C, Kamp O, Braam R, van Melle JP. Appropriate use criteria for echocardiography in the Netherlands. Neth Heart J 2017; 25:330-334. [PMID: 28247246 PMCID: PMC5405027 DOI: 10.1007/s12471-017-0960-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Introduction Appropriate use criteria (AUC) for echocardiography based on clinical scenarios were previously published by an American Task Force. We determined whether members of the Dutch Working Group on Echocardiography (WGE) would rate these scenarios in a similar way. Methods All 32 members of the WGE were invited to judge clinical scenarios independently using a blanked version of the previously published American version of AUC for echocardiography. During a face-to-face meeting, consensus about the final rating was reached by open discussion for each indication. For reasons of simplicity, the scores were reduced from a 9-point scale to a 3-point scale (indicating an appropriate, uncertain or inappropriate echo indication, respectively). Results Nine cardiologist members of the WGE reported their judgment on the echo cases (n = 153). Seventy-one indications were rated as appropriate, 35 were rated as uncertain, and 47 were rated as inappropriate. In 5% of the cases the rating was opposite to that in the original (appropriate compared with inappropriate and vice versa), whereas in 20% judgements differed by 1 level of appropriateness. After the consensus meeting, the appropriateness of 7 (5%) cases was judged differently compared with the original paper. Conclusions Echocardiography was rated appropriate when it is applied for an initial diagnosis, a change in clinical status or a change in patient management. However, in about 5% of the listed clinical scenarios, members of the Dutch WGE rated the AUC for echocardiography differently as compared with their American counterparts. Further research is warranted to analyse this decreased external validity. Electronic supplementary material The online version of this article (doi: 10.1007/s12471-017-0960-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- B J Bouma
- Department of Cardiology, AMC, Amsterdam, The Netherlands.
| | - R Riezenbos
- Department of Cardiology, OLVG, Amsterdam, The Netherlands
| | - A J Voogel
- Department of Cardiology, Spaarne Hospital, Hoofddorp, The Netherlands
| | - M H Veldhorst
- Department of Cardiology, Isala, Zwolle, The Netherlands
| | - W Jaarsma
- Department of Cardiology, St. Antonius Hospital, Nieuwegein, The Netherlands
| | - J Hrudova
- Department of Cardiology, St Antonius Hospital, Sneek, The Netherlands
| | - B Cernohorsky
- Department of Cardiology, St Antonius Hospital, Sneek, The Netherlands
| | - S Chamuleau
- Department of Cardiology, University Medical Center, Utrecht, The Netherlands
| | | | - R Breedveld
- Department of Cardiology, MCL, Leeuwarden, The Netherlands
| | - C Reichert
- Department of Cardiology, MCA, Alkmaar, The Netherlands
| | - O Kamp
- Department of Cardiology, VUmc and AMC, Amsterdam, The Netherlands
| | - R Braam
- Department of Cardiology, Gelre Hospitals, Apeldoorn, The Netherlands
| | - J P van Melle
- Department of Cardiology, University Medical Center Groningen, Groningen, The Netherlands
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Papageorgiou SN, Reichert C, Jäger A, Deschner J. Effect of overweight/obesity on response to periodontal treatment: systematic review and a meta-analysis. J Clin Periodontol 2015; 42:247-61. [DOI: 10.1111/jcpe.12365] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2014] [Indexed: 01/17/2023]
Affiliation(s)
- Spyridon N. Papageorgiou
- Department of Orthodontics; School of Dentistry; University of Bonn; Bonn Germany
- Department of Oral Technology; School of Dentistry; University of Bonn; Bonn Germany
- Clinical Research Unit 208; University of Bonn; Bonn Germany
| | - Christoph Reichert
- Department of Orthodontics; School of Dentistry; University of Bonn; Bonn Germany
| | - Andreas Jäger
- Department of Orthodontics; School of Dentistry; University of Bonn; Bonn Germany
- Clinical Research Unit 208; University of Bonn; Bonn Germany
| | - James Deschner
- Clinical Research Unit 208; University of Bonn; Bonn Germany
- Section of Experimental Dento-Maxillo-Facial Medicine; Center of Dento-Maxillo-Facial Medicine; University of Bonn; Bonn Germany
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Reichert C, Gölz L, Götz W, Wolf M, Deschner J, Jäger A. Dental and craniofacial characteristics in a patient with Hutchinson-Gilford progeria syndrome. J Orofac Orthop 2014; 75:251-63. [PMID: 25001855 DOI: 10.1007/s00056-014-0216-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Accepted: 01/31/2013] [Indexed: 11/28/2022]
Abstract
The Hutchinson-Gilford progeria syndrome (HGPS) is an exceptionally rare medical disorder caused by mutations in the lamin A/C gene. Affected patients display typical features of premature aging. Beside general medical disorders, these patients have several specific features related to the craniofacial phenotype and the oral cavity. In this article, the dental and craniofacial characteristics of a 9-year-old girl with HGPS are presented. It is the first report addressing orthodontic tooth movement and microbiological features in a HGPS patient. We describe and discuss pathologic findings and provide a detailed histology of the teeth which had to be extracted during initial treatment.
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Affiliation(s)
- Christoph Reichert
- Department of Orthodontics, Dental Hospital, University of Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany,
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Wolf M, Wurm A, Heinemann F, Gerber T, Reichert C, Jäger A, Götz W. The Effect of Patient Age on Bone Formation Using a Fully Synthetic Nanocrystalline Bone Augmentation Material in Maxillary Sinus Grafting. Int J Oral Maxillofac Implants 2014; 29:976-83. [DOI: 10.11607/jomi.3525] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Pires Gomes E, Reichert C, Lortholary O, Lecuit M, Charlier C. U-04: Prise en charge des femmes enceintes dans un service de maladies infectieuses : identification des difficultés et des axes d’amélioration. Med Mal Infect 2014. [DOI: 10.1016/s0399-077x(14)70353-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Reichert C, Fendrich R, Bernarding J, Tempelmann C, Hinrichs H, Rieger JW. Online tracking of the contents of conscious perception using real-time fMRI. Front Neurosci 2014; 8:116. [PMID: 24904260 PMCID: PMC4033165 DOI: 10.3389/fnins.2014.00116] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 05/02/2014] [Indexed: 11/13/2022] Open
Abstract
Perception is an active process that interprets and structures the stimulus input based on assumptions about its possible causes. We use real-time functional magnetic resonance imaging (rtfMRI) to investigate a particularly powerful demonstration of dynamic object integration in which the same physical stimulus intermittently elicits categorically different conscious object percepts. In this study, we simulated an outline object that is moving behind a narrow slit. With such displays, the physically identical stimulus can elicit categorically different percepts that either correspond closely to the physical stimulus (vertically moving line segments) or represent a hypothesis about the underlying cause of the physical stimulus (a horizontally moving object that is partly occluded). In the latter case, the brain must construct an object from the input sequence. Combining rtfMRI with machine learning techniques we show that it is possible to determine online the momentary state of a subject's conscious percept from time resolved BOLD-activity. In addition, we found that feedback about the currently decoded percept increased the decoding rates compared to prior fMRI recordings of the same stimulus without feedback presentation. The analysis of the trained classifier revealed a brain network that discriminates contents of conscious perception with antagonistic interactions between early sensory areas that represent physical stimulus properties and higher-tier brain areas. During integrated object percepts, brain activity decreases in early sensory areas and increases in higher-tier areas. We conclude that it is possible to use BOLD responses to reliably track the contents of conscious visual perception with a relatively high temporal resolution. We suggest that our approach can also be used to investigate the neural basis of auditory object formation and discuss the results in the context of predictive coding theory.
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Affiliation(s)
- Christoph Reichert
- Department of Neurology, University Medical Center A.ö.R. Magdeburg, Germany ; Department of Knowledge and Language Processing, Otto-von-Guericke University Magdeburg, Germany ; Forschungscampus STIMULATE Magdeburg, Germany
| | - Robert Fendrich
- Department of Neurology, University Medical Center A.ö.R. Magdeburg, Germany ; Department of Psychological and Brain Sciences, Dartmouth College Hanover, NH, USA
| | - Johannes Bernarding
- Institute for Biometry and Medical Informatics, Medical Faculty, Otto-von-Guericke University Magdeburg, Germany
| | - Claus Tempelmann
- Department of Neurology, University Medical Center A.ö.R. Magdeburg, Germany
| | - Hermann Hinrichs
- Department of Neurology, University Medical Center A.ö.R. Magdeburg, Germany ; Forschungscampus STIMULATE Magdeburg, Germany ; Department of Behavioral Neurology, Leibniz Institute for Neurobiology Magdeburg, Germany ; German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Germany ; Center for Behavioral Brain Sciences Magdeburg, Germany
| | - Jochem W Rieger
- Department of Applied Neurocognitive Psychology, Carl-von-Ossietzky University Oldenburg, Germany ; Research Center for Neurosensory Sciences, Carl-von-Ossietzky University Oldenburg, Germany
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Reichert C, Reichert P, Monnet-Tschudi F, Kupferschmidt H, Ceschi A, Rauber-Lüthy C. Seizures after single-agent overdose with pharmaceutical drugs: analysis of cases reported to a poison center. Clin Toxicol (Phila) 2014; 52:629-34. [PMID: 24844578 DOI: 10.3109/15563650.2014.918627] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
CONTEXT Seizures during intoxications with pharmaceuticals are a well-known complication. However, only a few studies report on drugs commonly involved and calculate the seizure potential of these drugs. OBJECTIVES To identify the pharmaceutical drugs most commonly associated with seizures after single-agent overdose, the seizure potential of these pharmaceuticals, the age-distribution of the cases with seizures and the ingested doses. METHODS A retrospective review of acute single-agent exposures to pharmaceuticals reported to the Swiss Toxicological Information Centre (STIC) between January 1997 and December 2010 was conducted. Exposures which resulted in at least one seizure were identified. The seizure potential of a pharmaceutical was calculated by dividing the number of cases with seizures by the number of all cases recorded with that pharmaceutical. Data were analyzed using descriptive statistics. RESULTS We identified 15,441 single-agent exposures. Seizures occurred in 313 cases. The most prevalent pharmaceuticals were mefenamic acid (51 of the 313 cases), citalopram (34), trimipramine (27), venlafaxine (23), tramadol (15), diphenhydramine (14), amitriptyline (12), carbamazepine (11), maprotiline (10), and quetiapine (10). Antidepressants were involved in 136 cases. Drugs with a high seizure potential were bupropion (31.6%, seizures in 6 of 19 cases, 95% CI: 15.4-50.0%), maprotiline (17.5%, 10/57, 95% CI: 9.8-29.4%), venlafaxine (13.7%, 23/168, 95% CI: 9.3-19.7%), citalopram (13.1%, 34/259, 95% CI: 9.5-17.8%), and mefenamic acid (10.9%, 51/470, 95% CI: 8.4-14.0%). In adolescents (15-19y/o) 23.9% (95% CI: 17.6-31.7%) of the cases involving mefenamic acid resulted in seizures, but only 5.7% (95% CI: 3.3-9.7%) in adults (≥ 20y/o; p < 0.001). For citalopram these numbers were 22.0% (95% CI: 12.8-35.2%) and 10.9% (95% CI: 7.1-16.4%), respectively (p = 0.058). The probability of seizures with mefenamic acid, citalopram, trimipramine, and venlafaxine increased as the ingested dose increased. CONCLUSIONS Antidepressants were frequently associated with seizures in overdose, but other pharmaceuticals, as mefenamic acid, were also associated with seizures in a considerable number of cases. Bupropion was the pharmaceutical with the highest seizure potential even if overdose with bupropion was uncommon in our sample. Adolescents might be more susceptible to seizures after mefenamic acid overdose than adults. "Part of this work is already published as a conference abstract for the XXXIV International Congress of the European Association of Poisons Centres and Clinical Toxicologists (EAPCCT) 27-30 May 2014, Brussels, Belgium." Abstract 8, Clin Toxicol 2014;52(4):298.
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Affiliation(s)
- C Reichert
- Swiss Toxicological Information Centre, Associated Institute of the University of Zürich , Zürich , Switzerland
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Affiliation(s)
- C Reichert
- Policlinic for Orthodontics, Welschnonnenstr. 17, 53119, Bonn, Germany,
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Reichert C. Autotransplantating of developing premolars. J Orofac Orthop 2014. [PMID: 24825835 DOI: 10.1007/s00056-014-0223-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Affiliation(s)
- C Reichert
- Policlinic for Orthodontics, Welschnonnenstr. 17, 53119, Bonn, Germany,
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Reichert C, Wenghoefer M, Kutschera E, Götz W, Jäger A. [Ridge preservation with synthetic nanocrystalline hydroxyapatite reduces the severity of gingival invaginations-a prospective clinical study]. J Orofac Orthop 2014; 75:7-15. [PMID: 24442552 DOI: 10.1007/s00056-013-0175-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 04/22/2013] [Indexed: 10/25/2022]
Abstract
BACKGROUND AND OBJECTIVE Gingival invaginations develop after tooth extraction and subsequent orthodontic space closure. Aetiological factors and long-term effects of gingival invaginations on oral health are nearly unknown. In addition, preventive or therapeutic strategies are rare. This prospective clinical study employing the split mouth technique was performed to investigate the effect of extraction socket augmentation with a synthetic nanocrystalline hydroxyapatite (NanoBone(®) Artoss, Rostock, Germany) on the incidence and degree of gingival invaginations. MATERIAL AND METHODS A total of 10 orthodontic patients with need for symmetric premolar extractions offering a total of 28 extractions were included in this trial. The study plan provided one extraction site to be augmented with synthetic nanocrystalline hydroxyapatite (NanoBone(®)), the other served as control. After primary wound healing, space closure was performed under defined biomechanical conditions. After space closure was accomplished, occurrence and degree of gingival invaginations as well as probing depths of the adjacent teeth mesial and distal to the extractions were determined and dental radiographs were taken. RESULTS The degree of gingival invaginations and probing depths mesial and distal of the extraction were significantly reduced on NanoBone(®) augmented extraction sites. In addition, 70% of the radiographs revealed translucent and hyperdense areas on the intervention side after space closure. Apical root resorption was found in 2 patients on both the NanoBone(®) side and the control side. CONCLUSION Ridge preservation with NanoBone(®) appeared to reduce the severity of gingival invaginations. Further investigation on long-term effects is mandatory to eliminate the appearance of adverse effects.
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Affiliation(s)
- Christoph Reichert
- Poliklinik für Kieferorthopädie, Universitätsklinikum, Rheinische Friedrich-Wilhelms-Universität Bonn, Welschnonnenstr. 17, 53111, Bonn, Deutschland,
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Reichert C, Bonze P, Rötung AK, Bienert-Zeit A. Approaches to cheek teeth removal after failed oral extraction in 23 horses. PFERDEHEILKUNDE 2014. [DOI: 10.21836/pem20140503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Braun U, Reichle SF, Reichert C, Hässig M, Stalder HP, Bachofen C, Peterhans E. Sheep persistently infected with Border disease readily transmit virus to calves seronegative to BVD virus. Vet Microbiol 2013; 168:98-104. [PMID: 24315041 DOI: 10.1016/j.vetmic.2013.11.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 09/04/2013] [Accepted: 11/04/2013] [Indexed: 11/27/2022]
Abstract
Bovine viral diarrhea- and Border disease viruses of sheep belong to the highly diverse genus pestivirus of the Flaviviridae. Ruminant pestiviruses may infect a wide range of domestic and wild cloven-hooved mammals (artiodactyla). Due to its economic importance, programs to eradicate bovine viral diarrhea are a high priority in the cattle industry. By contrast, Border disease is not a target of eradication, although the Border disease virus is known to be capable of also infecting cattle. In this work, we compared single dose experimental inoculation of calves with Border disease virus with co-mingling of calves with sheep persistently infected with this virus. As indicated by seroconversion, infection was achieved only in one out of seven calves with a dose of Border disease virus that was previously shown to be successful in calves inoculated with BVD virus. By contrast, all calves kept together with persistently infected sheep readily became infected with Border disease virus. The ease of viral transmission from sheep to cattle and the antigenic similarity of bovine and ovine pestiviruses may become a problem for demonstrating freedom of BVD by serology in the cattle population.
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Affiliation(s)
- U Braun
- Department of Farm Animals, University of Zurich, Winterthurer-strasse 260, CH-8057 Zurich, Switzerland
| | - S F Reichle
- Department of Farm Animals, University of Zurich, Winterthurer-strasse 260, CH-8057 Zurich, Switzerland
| | - C Reichert
- Department of Farm Animals, University of Zurich, Winterthurer-strasse 260, CH-8057 Zurich, Switzerland
| | - M Hässig
- Department of Farm Animals, University of Zurich, Winterthurer-strasse 260, CH-8057 Zurich, Switzerland
| | - H P Stalder
- Institute of Veterinary Virology, University of Bern, Länggass-Str. 122, P.O. Box 8644, CH-3001 Bern, Switzerland
| | - C Bachofen
- Institute of Veterinary Virology, University of Bern, Länggass-Str. 122, P.O. Box 8644, CH-3001 Bern, Switzerland
| | - E Peterhans
- Institute of Veterinary Virology, University of Bern, Länggass-Str. 122, P.O. Box 8644, CH-3001 Bern, Switzerland.
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Kettenbeil A, Reimann S, Reichert C, Keilig L, Jäger A, Bourauel C. Numerical simulation and biomechanical analysis of an orthodontically treated periodontally damaged dentition. J Orofac Orthop 2013; 74:480-93. [PMID: 24173364 DOI: 10.1007/s00056-013-0182-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 01/31/2013] [Indexed: 11/24/2022]
Abstract
BACKGROUND AND OBJECTIVE Once periodontitis has been completely resolved, one common follow-up method is to carry out orthodontic treatment to take advantage of the residual bone, i.e., via tooth intrusion. In this study, the biomechanical behavior of teeth in a reduced periodontium was studied by numerically simulating upper-incisor intrusion accomplished with various orthodontic mechanics. MATERIALS AND METHODS Using the finite element method, a patient-customized 3D model of a periodontally reduced dentition was generated in order to simulate tooth movement. The morphology of this upper-jaw model was derived from cone-beam computed tomography (CBCT) datasets of four patients. Material parameters were adopted from previous investigations, including teeth (E=20 GPa), periodontal ligament (PDL) (bilinear elastic; E1=0.05 MPa; E2=0.20 MPa; ε12=7%), and bone (homogeneous, isotropic; E=2 GPa). Two intrusion scenarios were used, the first drawing from Burstone's segmented-arch technique to intrude four splinted incisors at a time, and the second one using cantilevers to intrude single incisors. The aforementioned PDL material parameters were varied in several ways to simulate different biological and biomechanical states of PDL. All simulations were recalculated with an idealized, periodontally intact model to assess the effect of bone loss by way of comparison. RESULTS Single-tooth intrusion via cantilever mechanics was accompanied by less rotation than the segmented-arch approach. Both intrusion systems involved significantly greater degrees of tooth displacement and PDL load in the periodontally reduced model. CONCLUSION Periodontally reduced dentitions are associated with an increased load on periodontal tissue. This can be counteracted by reducing orthodontic force levels and by selecting mechanics that do not harm the tissue. In so doing, the use of numerical methods may greatly facilitate individualized computer-aided treatment-planning strategies.
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Affiliation(s)
- A Kettenbeil
- Endowed Chair of Oral Technology, Rheinische Friedrich-Wilhelms-Universität Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany
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Reichert C. Mandibular cortical shape index in non-standardised panoramic radiographs for identifying patients with osteoporosis as defined by the German Osteology Organization. J Orofac Orthop 2013. [PMID: 24158586 DOI: 10.1007/s00056-013-0184-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Affiliation(s)
- C Reichert
- Policlinic for Orthodontics, Rheinische Friedrich-Wilhelms Universität Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany,
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Reichert C. Dimensional alterations of extraction sites after different alveolar ridge preservation techniques-a volumetric study. J Orofac Orthop 2013. [PMID: 24158587 DOI: 10.1007/s00056-013-0185-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Affiliation(s)
- C Reichert
- Policlinic for Orthodontics, Rheinische Friedrich-Wilhelms Universität Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany,
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Affiliation(s)
- A. Bienert‐Zeit
- Clinic for HorsesUniversity of Veterinary Medicine Hannover, Foundation Germany
| | - A. Roetting
- Clinic for HorsesUniversity of Veterinary Medicine Hannover, Foundation Germany
| | - C. Reichert
- Clinic for HorsesUniversity of Veterinary Medicine Hannover, Foundation Germany
| | - B. Ohnesorge
- Clinic for HorsesUniversity of Veterinary Medicine Hannover, Foundation Germany
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Reichert C. Effectiveness of autofluorescence to identify suspicious oral lesions-a prospective, blinded clinical trial. J Orofac Orthop 2013. [PMID: 23649284 DOI: 10.1007/s00056-013-0148-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Affiliation(s)
- C Reichert
- Policlinic for Orthodontics, Rheinische Friedrich-Wilhelms Universität Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany,
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Reichert C. Randomized trial of partial vs. stepwise caries removal: 3-year follow-up. J Orofac Orthop 2013. [PMID: 23649283 DOI: 10.1007/s00056-013-0147-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Affiliation(s)
- C Reichert
- Policlinic for Orthodontics, Rheinische Friedrich-Wilhelms Universität Bonn, Welschnonnenstr. 17, 53111, Bonn, Germany,
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Reichert C, Kutschera E, Nienkemper M, Scharf S, Mengel M, Fimmers R, Fuhrmann C, Plötz C, Gölz L, Drescher D, Braumann B, Jäger A. Influence of time after extraction on the development of gingival invagination: study protocol for a multicenter pilot randomized controlled clinical trial. Trials 2013; 14:108. [PMID: 23782625 PMCID: PMC3748838 DOI: 10.1186/1745-6215-14-108] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 04/10/2013] [Indexed: 11/13/2022] Open
Abstract
Background Gingival invaginations are a common side effect of orthodontic therapy involving tooth extraction and subsequent space closure. Consequences of gingival invaginations are a jeopardized stability of the space closure and hampered oral hygiene. In a retrospective study, the factor time until initiation of orthodontic space closure after tooth extraction has been identified as a potential risk factor for the development of gingival invaginations. The aim of this pilot study is to proof this hypothesis and to enable a caseload calculation for further clinical trials. The referring question is: is it possible to reduce the number of developing gingival invaginations by initiation of orthodontic space closure after tooth extraction at an early point of time? Design The intended pilot study is designed as a multicenter randomized controlled clinical trial, comparing the impact of two different time intervals from tooth extraction to initiation of orthodontic space closure on the development of gingival invaginations. Forty participants, men and women in the age range of 11 to 30 years with orthodontically related indication for tooth extraction in the lower jaw, will be randomized 1:1 in one of two treatment groups. In group A the orthodontic tooth movement into the extraction area will be initiated in a time interval 2 to 4 weeks after tooth extraction. In group B the tooth movement will be initiated in a time interval >12 weeks after extraction. A possible effect of these treatment modalities on the development of gingival invaginations will be documented at the moment of space closure or 10 months +/- 14 days after initiation of space closure respectively, by clinical documentation of the primary (reduced number of gingival invagination) and the secondary endpoint (reduction of the severity of gingival invaginations). Trial registration Universal Trial Number U1111-1132-6655; German Clinical Trials Register DRKS00004248
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Affiliation(s)
- Christoph Reichert
- Department of Orthodontics, University Hospital Bonn, Welschnonnenstraße 17, 53111 Bonn, Germany.
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Reichert C, Götz W, Reimann S, Keilig L, Hagner M, Bourauel C, Jäger A. Resorption behavior of a nanostructured bone substitute: in vitro investigation and clinical application. J Orofac Orthop 2013; 74:165-74. [DOI: 10.1007/s00056-012-0136-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 11/02/2012] [Indexed: 11/30/2022]
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Reichert C, Ohnesorge B, Go L-M, Karlheim B, Rötting AK. Intermittent Rostral Displacement of the Palatopharyngeal Arch in a horse due to 4-BAD. PFERDEHEILKUNDE 2013. [DOI: 10.21836/pem20130605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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