1
|
Aquino G, Benz F, Dressle RJ, Gemignani A, Alfì G, Palagini L, Spiegelhalder K, Riemann D, Feige B. Towards the neurobiology of insomnia: A systematic review of neuroimaging studies. Sleep Med Rev 2024; 73:101878. [PMID: 38056381 DOI: 10.1016/j.smrv.2023.101878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 11/03/2023] [Accepted: 11/10/2023] [Indexed: 12/08/2023]
Abstract
Insomnia disorder signifies a major public health concern. The development of neuroimaging techniques has permitted to investigate brain mechanisms at a structural and functional level. The present systematic review aims at shedding light on functional, structural, and metabolic substrates of insomnia disorder by integrating the available published neuroimaging data. The databases PubMed, PsycARTICLES, PsycINFO, CINAHL and Web of Science were searched for case-control studies comparing neuroimaging data from insomnia patients and healthy controls. 85 articles were judged as eligible. For every observed finding of each study, the effect size was calculated from standardised mean differences, statistic parameters and figures, showing a marked heterogeneity that precluded a comprehensive quantitative analysis. From a qualitative point of view, considering the findings of significant group differences in the reported regions across the articles, this review highlights the major involvement of the anterior cingulate cortex, thalamus, insula, precuneus and middle frontal gyrus, thus supporting some central themes in the debate on the neurobiology of and offering interesting insights into the psychophysiology of sleep in this disorder.
Collapse
Affiliation(s)
- Giulia Aquino
- Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine - University of Pisa, Pisa, Italy.
| | - Fee Benz
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Raphael J Dressle
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Angelo Gemignani
- Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine - University of Pisa, Pisa, Italy
| | - Gaspare Alfì
- Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine - University of Pisa, Pisa, Italy
| | - Laura Palagini
- Department of Experimental and Clinic Medicine, Section of Psychiatry, University of Pisa, Pisa, Italy
| | - Kai Spiegelhalder
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Dieter Riemann
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Bernd Feige
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany; Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| |
Collapse
|
2
|
Menicucci D, Lunghi C, Zaccaro A, Morrone MC, Gemignani A. Mutual interaction between visual homeostatic plasticity and sleep in adult humans. eLife 2022; 11:70633. [PMID: 35972073 PMCID: PMC9417418 DOI: 10.7554/elife.70633] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 08/15/2022] [Indexed: 11/13/2022] Open
Abstract
Sleep and plasticity are highly interrelated, as sleep slow oscillations and sleep spindles are associated with consolidation of Hebbian-based processes. However, in adult humans, visual cortical plasticity is mainly sustained by homeostatic mechanisms, for which the role of sleep is still largely unknown. Here, we demonstrate that non-REM sleep stabilizes homeostatic plasticity of ocular dominance induced in adult humans by short-term monocular deprivation: the counterintuitive and otherwise transient boost of the deprived eye was preserved at the morning awakening (>6 hr after deprivation). Subjects exhibiting a stronger boost of the deprived eye after sleep had increased sleep spindle density in frontopolar electrodes, suggesting the involvement of distributed processes. Crucially, the individual susceptibility to visual homeostatic plasticity soon after deprivation correlated with the changes in sleep slow oscillations and spindle power in occipital sites, consistent with a modulation in early occipital visual cortex.
Collapse
Affiliation(s)
- Danilo Menicucci
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
| | - Claudia Lunghi
- Département d'études Cognitives, École Normale Supérieure, UMR 8248 CNRS, Paris, France
| | - Andrea Zaccaro
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
| | - Maria Concetta Morrone
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Angelo Gemignani
- Department of Surgical, Medical and Molecular and Critical Area Pathology, University of Pisa, Pisa, Italy
| |
Collapse
|
3
|
Sarasso S, D'Ambrosio S, Fecchio M, Casarotto S, Viganò A, Landi C, Mattavelli G, Gosseries O, Quarenghi M, Laureys S, Devalle G, Rosanova M, Massimini M. Local sleep-like cortical reactivity in the awake brain after focal injury. Brain 2021; 143:3672-3684. [PMID: 33188680 PMCID: PMC7805800 DOI: 10.1093/brain/awaa338] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 07/08/2020] [Accepted: 08/10/2020] [Indexed: 12/23/2022] Open
Abstract
The functional consequences of focal brain injury are thought to be contingent on neuronal alterations extending beyond the area of structural damage. This phenomenon, also known as diaschisis, has clinical and metabolic correlates but lacks a clear electrophysiological counterpart, except for the long-standing evidence of a relative EEG slowing over the injured hemisphere. Here, we aim at testing whether this EEG slowing is linked to the pathological intrusion of sleep-like cortical dynamics within an awake brain. We used a combination of transcranial magnetic stimulation and electroencephalography (TMS/EEG) to study cortical reactivity in a cohort of 30 conscious awake patients with chronic focal and multifocal brain injuries of ischaemic, haemorrhagic and traumatic aetiology. We found that different patterns of cortical reactivity typically associated with different brain states (coma, sleep, wakefulness) can coexist within the same brain. Specifically, we detected the occurrence of prominent sleep-like TMS-evoked slow waves and off-periods—reflecting transient suppressions of neuronal activity—in the area surrounding focal cortical injuries. These perilesional sleep-like responses were associated with a local disruption of signal complexity whereas complex responses typical of the awake brain were present when stimulating the contralesional hemisphere. These results shed light on the electrophysiological properties of the tissue surrounding focal brain injuries in humans. Perilesional sleep-like off-periods can disrupt network activity but are potentially reversible, thus representing a principled read-out for the neurophysiological assessment of stroke patients, as well as an interesting target for rehabilitation.
Collapse
Affiliation(s)
- Simone Sarasso
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, Milan, Italy
| | - Sasha D'Ambrosio
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, Milan, Italy.,Chalfont Centre for Epilepsy, Chalfont St. Peter, UK.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, UK
| | - Matteo Fecchio
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, Milan, Italy
| | - Silvia Casarotto
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, Milan, Italy
| | - Alessandro Viganò
- Istituto Di Ricovero e Cura a Carattere Scientifico, Fondazione Don Carlo Gnocchi, Milan, Italy
| | - Cristina Landi
- Fondazione Europea per la Ricerca Biomedica Onlus, Milan, Italy
| | | | - Olivia Gosseries
- Coma Science Group, University and University Hospital of Liege, GIGA-Consciousness, 4000 Liege, Belgium
| | - Matteo Quarenghi
- Unità Operativa Radiologia, Azienda Ospedaliera Vizzolo P -Risonanza Magnetica- ASST Melegnano e Martesana, Vizzolo Predabissi, Italy
| | - Steven Laureys
- Coma Science Group, University and University Hospital of Liege, GIGA-Consciousness, 4000 Liege, Belgium
| | - Guya Devalle
- Istituto Di Ricovero e Cura a Carattere Scientifico, Fondazione Don Carlo Gnocchi, Milan, Italy
| | - Mario Rosanova
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, Milan, Italy.,Fondazione Europea per la Ricerca Biomedica Onlus, Milan, Italy
| | - Marcello Massimini
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, Milan, Italy.,Istituto Di Ricovero e Cura a Carattere Scientifico, Fondazione Don Carlo Gnocchi, Milan, Italy
| |
Collapse
|
4
|
Menicucci D, Piarulli A, Laurino M, Zaccaro A, Agrimi J, Gemignani A. Sleep slow oscillations favour local cortical plasticity underlying the consolidation of reinforced procedural learning in human sleep. J Sleep Res 2020; 29:e13117. [PMID: 32592318 DOI: 10.1111/jsr.13117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 05/14/2020] [Accepted: 05/18/2020] [Indexed: 11/29/2022]
Abstract
We investigated changes of slow-wave activity and sleep slow oscillations in the night following procedural learning boosted by reinforcement learning, and how these changes correlate with behavioural output. In the Task session, participants had to reach a visual target adapting cursor's movements to compensate an angular deviation introduced experimentally, while in the Control session no deviation was applied. The task was repeated at 13:00 hours, 17:00 hours and 23:00 hours before sleep, and at 08:00 hours after sleep. The deviation angle was set at 15° (13:00 hours and 17:00 hours) and increased to 45° (reinforcement) at 23:00 hours and 08:00 hours. Both for Task and Control nights, high-density electroencephalogram sleep recordings were carried out (23:30-19:30 hours). The Task night as compared with the Control night showed increases of: (a) slow-wave activity (absolute power) over the whole scalp; (b) slow-wave activity (relative power) in left centro-parietal areas; (c) sleep slow oscillations rate in sensorimotor and premotor areas; (d) amplitude of pre-down and up states in premotor regions, left sensorimotor and right parietal regions; (e) sigma crowning the up state in right parietal regions. After Task night, we found an improvement of task performance showing correlations with sleep slow oscillations rate in right premotor, sensorimotor and parietal regions. These findings suggest a key role of sleep slow oscillations in procedural memories consolidation. The diverse components of sleep slow oscillations selectively reflect the network activations related to the reinforced learning of a procedural visuomotor task. Indeed, areas specifically involved in the task stand out as those with a significant association between sleep slow oscillations rate and overnight improvement in task performance.
Collapse
Affiliation(s)
- Danilo Menicucci
- Department of Surgical, Medical, Molecular Pathology and Critical Medicine, University of Pisa, Pisa, Italy
| | - Andrea Piarulli
- Department of Surgical, Medical, Molecular Pathology and Critical Medicine, University of Pisa, Pisa, Italy.,Coma Science Group, GIGA-Consciousness, University of Liège and University Hospital of Liège, Liège, Belgium
| | - Marco Laurino
- Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | - Andrea Zaccaro
- Department of Surgical, Medical, Molecular Pathology and Critical Medicine, University of Pisa, Pisa, Italy
| | - Jacopo Agrimi
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Angelo Gemignani
- Department of Surgical, Medical, Molecular Pathology and Critical Medicine, University of Pisa, Pisa, Italy.,Institute of Clinical Physiology, National Research Council, Pisa, Italy.,Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy
| |
Collapse
|
5
|
Hao X, Yang S, Wang J, Deng B, Wei X, Yi G. Efficient Implementation of Cerebellar Purkinje Cell With the CORDIC Algorithm on LaCSNN. Front Neurosci 2019; 13:1078. [PMID: 31680818 PMCID: PMC6803503 DOI: 10.3389/fnins.2019.01078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 09/24/2019] [Indexed: 01/10/2023] Open
Abstract
Purkinje cell is an important neuron for the cerebellar information processing. In this work, we present an efficient implementation of a cerebellar Purkinje model using the Coordinate Rotation Digital Computer (CORDIC) algorithm and implement it on a Large-Scale Conductance-Based Spiking Neural Networks (LaCSNN) system with cost-efficient multiplier-less methods, which are more suitable for large-scale neural networks. The CORDIC-based Purkinje model has been compared with the original model in terms of the voltage activities, dynamic mechanisms, precision, and hardware resource utilization. The results show that the CORDIC-based Purkinje model can reproduce the same biological activities and dynamical mechanisms as the original model with slight deviation. In the aspect of the hardware implementation, it can use only logic resources, so it provides an efficient way for maximizing the FPGA resource utilization, thereby expanding the scale of neural networks that can be implemented on FPGAs.
Collapse
Affiliation(s)
- Xinyu Hao
- School of Electrical and Information Engineering, Tianjin University, Tianjin, China
| | - Shuangming Yang
- School of Electrical and Information Engineering, Tianjin University, Tianjin, China
| | - Jiang Wang
- School of Electrical and Information Engineering, Tianjin University, Tianjin, China
| | - Bin Deng
- School of Electrical and Information Engineering, Tianjin University, Tianjin, China
| | - Xile Wei
- School of Electrical and Information Engineering, Tianjin University, Tianjin, China
| | - Guosheng Yi
- School of Electrical and Information Engineering, Tianjin University, Tianjin, China
| |
Collapse
|
6
|
Laurino M, Piarulli A, Menicucci D, Gemignani A. Local Gamma Activity During Non-REM Sleep in the Context of Sensory Evoked K-Complexes. Front Neurosci 2019; 13:1094. [PMID: 31680829 PMCID: PMC6803494 DOI: 10.3389/fnins.2019.01094] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Accepted: 09/30/2019] [Indexed: 11/13/2022] Open
Abstract
K-complexes (KCs) and Sleep Slow Oscillations (SSOs) are the EEG expression of neuronal bistability during deeper stages Non-REM sleep. They are characterized by a deep negative deflection lasting about half-a-second, sustained, at the cortical level, by a widespread and synchronized neuronal hyperpolarization (i.e., electrical silence). The phase of hyperpolarization is followed by a period of intense and synchronized neuronal firing (i.e., depolarization phase) resulting at the EEG level, in a large positive deflection (lasting about 0.5 s) and a concurrent high frequency activity (i.e., spindles). Both KCs and SSOs rather than being “local” phenomena, propagate over large sections of the cortex. These features suggest that bistability is a large-scale network phenomenon, possibly driven by a propagating excitatory activity and involving wide populations of synchronized neurons. We have recently shown that KCs and SSOs include a positive bump preceding the negative peak and that for sensory-evoked KCs this bump coincides with the P200 wave. We demonstrated that the P200 has a sensory-modality specific localization, as it is firstly elicited in the primary sensory areas related to the stimulus, which in turn receive projections from the thalamic core. We observed that the P200 acts as a propagating excitatory activity and hypothesized that it could play a key role in inducing the opening of K+ channels, and hence the cortical hyperpolarization. Here we demonstrate that the P200 is sustained by a high-frequency excitation bringing further support to its role in triggering bistability. We show that the P200 has a higher power density in gamma band as compared to the P900 coherently for all sensory modalities, and we confirm that the latter wave is crowned by higher activity in sigma-beta bands. Finally, we characterize the P200 gamma activity at the cortical level in terms of spatial localization and temporal dynamics, demonstrating that it emerges in sensory stimulus-specific primary areas and travels over the cortical mantle spreading toward fronto-central associative areas and fading concurrently with the N550 onset.
Collapse
Affiliation(s)
- Marco Laurino
- Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | - Andrea Piarulli
- Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy.,Coma Science Group, GIGA Consciousness, University of Liège, Liège, Belgium
| | - Danilo Menicucci
- Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
| | - Angelo Gemignani
- Institute of Clinical Physiology, National Research Council, Pisa, Italy.,Department of Surgical, Medical, Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
| |
Collapse
|
7
|
The neurophysiological basis of excessive daytime sleepiness: suggestions of an altered state of consciousness. Sleep Breath 2019; 24:15-23. [PMID: 31140116 DOI: 10.1007/s11325-019-01865-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/03/2019] [Accepted: 05/08/2019] [Indexed: 10/26/2022]
Abstract
Excessive daytime sleepiness (EDS) is characterized by difficulty staying awake during daytime, though additional features may be present. EDS is a significant problem for clinical and non-clinical populations, being associated with a range of negative outcomes that also represent a burden for society. Extreme EDS is associated with sleep disorders, most notably the central hypersomnias such as narcolepsy, Kleine-Levin syndrome, and idiopathic hypersomnia (IH). Although investigation of these conditions indicates that EDS results from diminished sleep quality, the underlying cause for this impairment remains uncertain. One possibility could be that previous research has been too narrow in scope with insufficient attention paid to non-sleep-related aspects. Here, we offer a broader perspective in which findings concerning the impact of EDS on cortical functioning are interpreted in relation to current understanding about the neural basis of consciousness. Alterations in the spatial distribution of cortical activity, in particular reduced connectivity of frontal cortex, suggest that EDS is associated with an altered state of consciousness.
Collapse
|
8
|
Rosanova M, Fecchio M, Casarotto S, Sarasso S, Casali AG, Pigorini A, Comanducci A, Seregni F, Devalle G, Citerio G, Bodart O, Boly M, Gosseries O, Laureys S, Massimini M. Sleep-like cortical OFF-periods disrupt causality and complexity in the brain of unresponsive wakefulness syndrome patients. Nat Commun 2018; 9:4427. [PMID: 30356042 PMCID: PMC6200777 DOI: 10.1038/s41467-018-06871-1] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 10/01/2018] [Indexed: 12/21/2022] Open
Abstract
Unresponsive wakefulness syndrome (UWS) patients may retain intact portions of the thalamocortical system that are spontaneously active and reactive to sensory stimuli but fail to engage in complex causal interactions, resulting in loss of consciousness. Here, we show that loss of brain complexity after severe injuries is due to a pathological tendency of cortical circuits to fall into silence (OFF-period) upon receiving an input, a behavior typically observed during sleep. Spectral and phase domain analysis of EEG responses to transcranial magnetic stimulation reveals the occurrence of OFF-periods in the cortex of UWS patients (N = 16); these events never occur in healthy awake individuals (N = 20) but are similar to those detected in healthy sleeping subjects (N = 8). Crucially, OFF-periods impair local causal interactions, and prevent the build-up of global complexity in UWS. Our findings link potentially reversible local events to global brain dynamics that are relevant for pathological loss and recovery of consciousness. Many brain-injured patients retain large cortical islands that are intact, active and reactive but blocked in a state of low complexity, leading to unconsciousness. Here, the authors show that this loss of complexity is due to the pathological engagement of sleep-like neuronal mechanisms.
Collapse
Affiliation(s)
- M Rosanova
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, 20157, Italy.,Fondazione Europea per la Ricerca Biomedica Onlus, Milan, 20063, Italy.,Neurointensive Care Unit, ASTT Grande Ospedale Metropolitano Niguarda, Milan, 20162, Italy
| | - M Fecchio
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, 20157, Italy
| | - S Casarotto
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, 20157, Italy.,IRCCS Fondazione Don Gnocchi, Milan, 20149, Italy
| | - S Sarasso
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, 20157, Italy
| | - A G Casali
- Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo, Sao Jose dos Campos, 12231-280, Brazil
| | - A Pigorini
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, 20157, Italy
| | - A Comanducci
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, 20157, Italy
| | - F Seregni
- Department of Paediatrics, Cambridge University Hospital NHS Foundation Trust, Cambridge, CB2 0QQ, UK
| | - G Devalle
- IRCCS Fondazione Don Gnocchi, Milan, 20149, Italy
| | - G Citerio
- Scuola di Medicina e Chirurgia, University of Milan Bicocca, Milan, 20126, Italy
| | - O Bodart
- GIGA-consciousness, Coma Science Group, University and University Hospital of Liège, Liège, 4000, Belgium
| | - M Boly
- Department of Neurology, University of Wisconsin, Madison, WI, 53705, USA.,Department of Psychiatry, University of Wisconsin, Madison, WI, 53719, USA
| | - O Gosseries
- GIGA-consciousness, Coma Science Group, University and University Hospital of Liège, Liège, 4000, Belgium
| | - S Laureys
- GIGA-consciousness, Coma Science Group, University and University Hospital of Liège, Liège, 4000, Belgium
| | - M Massimini
- Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, 20157, Italy. .,IRCCS Fondazione Don Gnocchi, Milan, 20149, Italy.
| |
Collapse
|
9
|
Physiological Ripples (± 100 Hz) in Spike-Free Scalp EEGs of Children With and Without Epilepsy. Brain Topogr 2017; 30:739-746. [PMID: 28917017 PMCID: PMC5641281 DOI: 10.1007/s10548-017-0590-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 09/06/2017] [Indexed: 12/18/2022]
Abstract
Pathological high frequency oscillations (HFOs, >80 Hz) are considered new biomarkers for epilepsy. They have mostly been recorded invasively, but pathological ripples (80-250 Hz) can also be found in scalp EEGs with frequent epileptiform spikes. Physiological HFOs also exist. They have been recorded invasively in hippocampus and neocortex. There are no reports of spontaneously occurring physiological HFOs recorded with scalp EEG. We aimed to study ripples in spike-free scalp EEGs. We included 23 children (6 with, 17 without epilepsy) who had an EEG without interictal epileptiform spikes recorded during sleep. We differentiated true ripples from spurious ripples such as filtering effects of sharp artifacts and high frequency components of muscle artifacts by viewing ripples simultaneously in bipolar and average montage and double-checking the unfiltered signal. We calculated mean frequency, duration and root mean square amplitude of the ripples, and studied their shape and distribution. We found ripples in EEGs of 20 out of 23 children (4 with, 16 without epilepsy). Ripples had a regular shape and occurred mostly on central and midline channels. Mean frequency was 102 Hz, mean duration 70 ms, mean root mean square amplitude 0.95 µV. Ripples occurring in normal EEGs of children without epilepsy were considered physiological; the similarity in appearance suggested that the ripples occurring in normal EEGs of children with epilepsy were also physiological. The finding that it is possible to study physiological neocortical ripples in scalp EEG paves the way for investigating their occurrence during brain development and their relation with cognitive functioning.
Collapse
|
10
|
Neural Markers of Responsiveness to the Environment in Human Sleep. J Neurosci 2017; 36:6583-96. [PMID: 27307244 DOI: 10.1523/jneurosci.0902-16.2016] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 05/14/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Sleep is characterized by a loss of behavioral responsiveness. However, recent research has shown that the sleeping brain is not completely disconnected from its environment. How neural activity constrains the ability to process sensory information while asleep is yet unclear. Here, we instructed human volunteers to classify words with lateralized hand responses while falling asleep. Using an electroencephalographic (EEG) marker of motor preparation, we show how responsiveness is modulated across sleep. These modulations are tracked using classic event-related potential analyses complemented by Lempel-Ziv complexity (LZc), a measure shown to track arousal in sleep and anesthesia. Neural activity related to the semantic content of stimuli was conserved in light non-rapid eye movement (NREM) sleep. However, these processes were suppressed in deep NREM sleep and, importantly, also in REM sleep, despite the recovery of wake-like neural activity in the latter. In NREM sleep, sensory activations were counterbalanced by evoked down states, which, when present, blocked further processing of external information. In addition, responsiveness markers correlated positively with baseline complexity, which could be related to modulation in sleep depth. In REM sleep, however, this relationship was reversed. We therefore propose that, in REM sleep, endogenously generated processes compete with the processing of external input. Sleep can thus be seen as a self-regulated process in which external information can be processed in lighter stages but suppressed in deeper stages. Last, our results suggest drastically different gating mechanisms in NREM and REM sleep. SIGNIFICANCE STATEMENT Previous research has tempered the notion that sleepers are isolated from their environment. Here, we pushed this idea forward and examined, across all sleep stages, the brain's ability to flexibly process sensory information, up to the decision level. We extracted an EEG marker of motor preparation to determine the completion of the sensory processing chain and explored how it is constrained by baseline and evoked neural activity. In NREM sleep, slow waves elicited by stimuli appeared to block response preparation. We also used a novel analytic approach (Lempel-Ziv complexity) and showed that the ability to process external information correlates with neural complexity. A reversal of the correlation between complexity and motor indices in REM sleep suggests drastically different gating mechanisms across sleep stages.
Collapse
|
11
|
Schellenberger Costa M, Weigenand A, Ngo HVV, Marshall L, Born J, Martinetz T, Claussen JC. A Thalamocortical Neural Mass Model of the EEG during NREM Sleep and Its Response to Auditory Stimulation. PLoS Comput Biol 2016; 12:e1005022. [PMID: 27584827 PMCID: PMC5008627 DOI: 10.1371/journal.pcbi.1005022] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 06/17/2016] [Indexed: 11/18/2022] Open
Abstract
Few models exist that accurately reproduce the complex rhythms of the thalamocortical system that are apparent in measured scalp EEG and at the same time, are suitable for large-scale simulations of brain activity. Here, we present a neural mass model of the thalamocortical system during natural non-REM sleep, which is able to generate fast sleep spindles (12–15 Hz), slow oscillations (<1 Hz) and K-complexes, as well as their distinct temporal relations, and response to auditory stimuli. We show that with the inclusion of detailed calcium currents, the thalamic neural mass model is able to generate different firing modes, and validate the model with EEG-data from a recent sleep study in humans, where closed-loop auditory stimulation was applied. The model output relates directly to the EEG, which makes it a useful basis to develop new stimulation protocols. Sleep plays a pivotal role for the consolidation of memory. While REM sleep had originally been the focus of research due to its similarity with wakefulness, more recent studies suggest that different sleep stages are responsible for the consolidation of different types of memory. To better understand the changes in neuronal dynamics between the different sleep stages, neural mass models are a valuable tool, as they relate directly to the large-scale dynamics measured by an EEG. Here, we present a model of the sleeping thalamocortical system. We first show that the isolated thalamic submodule is able to generate different oscillatory behavior found in vivo. Furthermore, the full thalamocortical model reproduces the EEG of sleep stages N2 and N3 and preserves the temporal relationship between cortical K-complexes/slow oscillations and thalamic sleep spindles. A comparison with event related potential data from a recent sleep study in humans demonstrates its possible application in predicting the outcome of external stimulation on EEG rhythms. Our study shows, that a neural mass model incorporating few key mechanisms is sufficient to reproduce the complex brain dynamics observed during sleep.
Collapse
Affiliation(s)
- Michael Schellenberger Costa
- Institute for Neuro- and Bioinformatics, University of Lübeck, Lübeck, Germany
- Institute for Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
- * E-mail:
| | - Arne Weigenand
- Institute for Neuro- and Bioinformatics, University of Lübeck, Lübeck, Germany
- Graduate School for Computing in Medicine and Life Science, University of Lübeck, Lübeck, Germany
| | - Hong-Viet V. Ngo
- Institute for Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
| | - Lisa Marshall
- Graduate School for Computing in Medicine and Life Science, University of Lübeck, Lübeck, Germany
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Jan Born
- Institute for Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany
- Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Thomas Martinetz
- Institute for Neuro- and Bioinformatics, University of Lübeck, Lübeck, Germany
- Graduate School for Computing in Medicine and Life Science, University of Lübeck, Lübeck, Germany
| | - Jens Christian Claussen
- Institute for Neuro- and Bioinformatics, University of Lübeck, Lübeck, Germany
- Computational Systems Biology, Jacobs University Bremen, Bremen, Germany
| |
Collapse
|
12
|
Sarasso S, Boly M, Napolitani M, Gosseries O, Charland-Verville V, Casarotto S, Rosanova M, Casali AG, Brichant JF, Boveroux P, Rex S, Tononi G, Laureys S, Massimini M. Consciousness and Complexity during Unresponsiveness Induced by Propofol, Xenon, and Ketamine. Curr Biol 2015; 25:3099-105. [PMID: 26752078 DOI: 10.1016/j.cub.2015.10.014] [Citation(s) in RCA: 221] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 09/28/2015] [Accepted: 10/05/2015] [Indexed: 10/22/2022]
Abstract
A common endpoint of general anesthetics is behavioral unresponsiveness, which is commonly associated with loss of consciousness. However, subjects can become disconnected from the environment while still having conscious experiences, as demonstrated by sleep states associated with dreaming. Among anesthetics, ketamine is remarkable in that it induces profound unresponsiveness, but subjects often report "ketamine dreams" upon emergence from anesthesia. Here, we aimed at assessing consciousness during anesthesia with propofol, xenon, and ketamine, independent of behavioral responsiveness. To do so, in 18 healthy volunteers, we measured the complexity of the cortical response to transcranial magnetic stimulation (TMS)--an approach that has proven helpful in assessing objectively the level of consciousness irrespective of sensory processing and motor responses. In addition, upon emergence from anesthesia, we collected reports about conscious experiences during unresponsiveness. Both frontal and parietal TMS elicited a low-amplitude electroencephalographic (EEG) slow wave corresponding to a local pattern of cortical activation with low complexity during propofol anesthesia, a high-amplitude EEG slow wave corresponding to a global, stereotypical pattern of cortical activation with low complexity during xenon anesthesia, and a wakefulness-like, complex spatiotemporal activation pattern during ketamine anesthesia. Crucially, participants reported no conscious experience after emergence from propofol and xenon anesthesia, whereas after ketamine they reported long, vivid dreams unrelated to the external environment. These results are relevant because they suggest that brain complexity may be sensitive to the presence of disconnected consciousness in subjects who are considered unconscious based on behavioral responses.
Collapse
Affiliation(s)
- Simone Sarasso
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, 20157 Milan, Italy
| | - Melanie Boly
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA; Department of Neurology, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Martino Napolitani
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, 20157 Milan, Italy; Dipartimento di Scienze Clinico-chirurgiche, Diagnostiche e Pediatriche, Sezione di Anestesia Rianimazione e Terapia Antalgica, Università degli Studi di Pavia, SC Anestesia e Rianimazione, Fondazione IRCCS Policlinico S. Matteo, 27100 Pavia, Italy
| | - Olivia Gosseries
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA; Coma Science Group, University and University Hospital of Liège, GIGA-Research B34, 4000 Liège, Belgium
| | - Vanessa Charland-Verville
- Coma Science Group, University and University Hospital of Liège, GIGA-Research B34, 4000 Liège, Belgium
| | - Silvia Casarotto
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, 20157 Milan, Italy
| | - Mario Rosanova
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, 20157 Milan, Italy
| | - Adenauer Girardi Casali
- Institute of Science and Technology, Federal University of São Paulo, 12231-280 São José dos Campos, Brazil
| | - Jean-Francois Brichant
- Department of Anesthesia and Intensive Care Medicine, CHU Sart Tilman University Hospital, University of Liège, 4000 Liège, Belgium
| | - Pierre Boveroux
- Department of Anesthesia and Intensive Care Medicine, CHU Sart Tilman University Hospital, University of Liège, 4000 Liège, Belgium
| | - Steffen Rex
- Department of Anaesthesiology, University Hospitals of the KU Leuven, KU Leuven, 3000 Leuven, Belgium; Department of Cardiovascular Sciences, University Hospitals of the KU Leuven, KU Leuven, 3000 Leuven, Belgium
| | - Giulio Tononi
- Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA
| | - Steven Laureys
- Coma Science Group, University and University Hospital of Liège, GIGA-Research B34, 4000 Liège, Belgium.
| | - Marcello Massimini
- Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università degli Studi di Milano, 20157 Milan, Italy; Istituto Di Ricovero e Cura a Carattere Scientifico, Fondazione Don Carlo Gnocchi, 20148 Milan, Italy.
| |
Collapse
|
13
|
Allegrini P, Paradisi P, Menicucci D, Laurino M, Piarulli A, Gemignani A. Self-organized dynamical complexity in human wakefulness and sleep: different critical brain-activity feedback for conscious and unconscious states. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 92:032808. [PMID: 26465529 PMCID: PMC4909144 DOI: 10.1103/physreve.92.032808] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Indexed: 06/05/2023]
Abstract
Criticality reportedly describes brain dynamics. The main critical feature is the presence of scale-free neural avalanches, whose auto-organization is determined by a critical branching ratio of neural-excitation spreading. Other features, directly associated to second-order phase transitions, are: (i) scale-free-network topology of functional connectivity, stemming from suprathreshold pairwise correlations, superimposable, in waking brain activity, with that of ferromagnets at Curie temperature; (ii) temporal long-range memory associated to renewal intermittency driven by abrupt fluctuations in the order parameters, detectable in human brain via spatially distributed phase or amplitude changes in EEG activity. Herein we study intermittent events, extracted from 29 night EEG recordings, including presleep wakefulness and all phases of sleep, where different levels of mentation and consciousness are present. We show that while critical avalanching is unchanged, at least qualitatively, intermittency and functional connectivity, present during conscious phases (wakefulness and REM sleep), break down during both shallow and deep non-REM sleep. We provide a theory for fragmentation-induced intermittency breakdown and suggest that the main difference between conscious and unconscious states resides in the backwards causation, namely on the constraints that the emerging properties at large scale induce to the lower scales. In particular, while in conscious states this backwards causation induces a critical slowing down, preserving spatiotemporal correlations, in dreamless sleep we see a self-organized maintenance of moduli working in parallel. Critical avalanches are still present, and establish transient auto-organization, whose enhanced fluctuations are able to trigger sleep-protecting mechanisms that reinstate parallel activity. The plausible role of critical avalanches in dreamless sleep is to provide a rapid recovery of consciousness, if stimuli are highly arousing.
Collapse
Affiliation(s)
- Paolo Allegrini
- Istituto di Scienze della Vita, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 7, 56127 Pisa, Italy
- Istituto di Fisiologia Clinica (IFC-CNR), Via Moruzzi 1, 56124 Pisa, Italy
| | - Paolo Paradisi
- Istituto di Scienza e Tecnologie dell'Informazione "A. Faedo" (ISTI-CNR), Via Moruzzi 1, 56124 Pisa, Italy
| | - Danilo Menicucci
- Istituto di Fisiologia Clinica (IFC-CNR), Via Moruzzi 1, 56124 Pisa, Italy
- Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia, Via Savi 10, 56126 Pisa, Italy
| | - Marco Laurino
- Istituto di Scienze della Vita, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 7, 56127 Pisa, Italy
- Istituto di Fisiologia Clinica (IFC-CNR), Via Moruzzi 1, 56124 Pisa, Italy
| | - Andrea Piarulli
- PERCRO laboratory, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 7, 56127 Pisa, Italy
| | - Angelo Gemignani
- Istituto di Scienze della Vita, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 7, 56127 Pisa, Italy
- Istituto di Fisiologia Clinica (IFC-CNR), Via Moruzzi 1, 56124 Pisa, Italy
- Dipartimento di Patologia Chirurgica, Medica, Molecolare e dell'Area Critica, Università di Pisa, Via Savi 10, 56126 Pisa, Italy
| |
Collapse
|
14
|
Looking for a precursor of spontaneous Sleep Slow Oscillations in human sleep: The role of the sigma activity. Int J Psychophysiol 2015; 97:99-107. [PMID: 26003553 DOI: 10.1016/j.ijpsycho.2015.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 05/12/2015] [Accepted: 05/13/2015] [Indexed: 11/23/2022]
Abstract
Sleep Slow Oscillations (SSOs), paradigmatic EEG markers of cortical bistability (alternation between cellular downstates and upstates), and sleep spindles, paradigmatic EEG markers of thalamic rhythm, are two hallmarks of sleeping brain. Selective thalamic lesions are reportedly associated to reductions of spindle activity and its spectrum ~14 Hz (sigma), and to alterations of SSO features. This apparent, parallel behavior suggests that thalamo-cortical entrainment favors cortical bistability. Here we investigate temporally-causal associations between thalamic sigma activity and shape, topology, and dynamics of SSOs. We recorded sleep EEG and studied whether spatio-temporal variability of SSO amplitude, negative slope (synchronization in downstate falling) and detection rate are driven by cortical-sigma-activity expression (12-18Hz), in 3 consecutive 1s-EEG-epochs preceding each SSO event (Baselines). We analyzed: (i) spatial variability, comparing maps of baseline sigma power and of SSO features, averaged over the first sleep cycle; (ii) event-by-event shape variability, computing for each electrode correlations between baseline sigma power and amplitude/slope of related SSOs; (iii) event-by-event spreading variability, comparing baseline sigma power in electrodes showing an SSO event with the homologous ones, spared by the event. The scalp distribution of baseline sigma power mirrored those of SSO amplitude and slope; event-by-event variability in baseline sigma power was associated with that in SSO amplitude in fronto-central areas; within each SSO event, electrodes involved in cortical bistability presented higher baseline sigma activity than those free of SSO. In conclusion, spatio-temporal variability of thalamocortical entrainment, measured by background sigma activity, is a reliable estimate of the cortical proneness to bistability.
Collapse
|
15
|
Gemignani J, Agrimi J, Cheli E, Gemignani A, Laurino M, Allegrini P, Landi A, Menicucci D. Pattern recognition with adaptive-thresholds for sleep spindle in high density EEG signals. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2015:594-7. [PMID: 26736332 PMCID: PMC4888948 DOI: 10.1109/embc.2015.7318432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Medicine and Surgery, University of Pisa, via Savi 10, 56126, Pisa, Italy Sleep spindles are electroencephalographic oscillations peculiar of non-REM sleep, related to neuronal mechanisms underlying sleep restoration and learning consolidation. Based on their very singular morphology, sleep spindles can be visually recognized and detected, even though this approach can lead to significant mis-detections. For this reason, many efforts have been put in developing a reliable algorithm for spindle automatic detection, and a number of methods, based on different techniques, have been tested via visual validation. This work aims at improving current pattern recognition procedures for sleep spindles detection by taking into account their physiological sources of variability. We provide a method as a synthesis of the current state of art that, improving dynamic threshold adaptation, is able to follow modification of spindle characteristics as a function of sleep depth and inter-subjects variability. The algorithm has been applied to physiological data recorded by a high density EEG in order to perform a validation based on visual inspection and on evaluation of expected results from normal night sleep in healthy subjects.
Collapse
Affiliation(s)
- Jessica Gemignani
- European Space Agency, Advanced Concepts Team, ESTEC, Keplerlaan 1- 2201 AZ, Noordwijk, The Netherlands,
| | - Jacopo Agrimi
- Institute of Life Sciences, Scuola Superiore SantAnna, Piazza Martiri della Liberta 33, 56127, Pisa, Italy
| | - Enrico Cheli
- Department of Surgical, Medical, Molecular and Critical Area Pathology, University of Pisa, via Savi 10, 56126, Pisa, Italy
| | - Angelo Gemignani
- Department of Surgical, Medical, Molecular and Critical Area Pathology, University of Pisa, via Savi 10, 56126, Pisa, Italy
| | - Marco Laurino
- Institute of Life Sciences, Scuola Superiore SantAnna, Piazza Martiri della Liberta 33, 56127, Pisa, Italy
| | - Paolo Allegrini
- Institute of Life Sciences, Scuola Superiore SantAnna, Piazza Martiri della Liberta 33, 56127, Pisa, Italy
| | - Alberto Landi
- Department of Electrical Systems and Automation, University of Pisa, Largo Lucio Lazzarino - 56122 Pisa - Italy
| | - Danilo Menicucci
- Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, via Savi 10, 56126, Pisa, Italy
| |
Collapse
|
16
|
Gemignani A, Piarulli A, Menicucci D, Laurino M, Rota G, Mastorci F, Gushin V, Shevchenko O, Garbella E, Pingitore A, Sebastiani L, Bergamasco M, L'Abbate A, Allegrini P, Bedini R. How stressful are 105days of isolation? Sleep EEG patterns and tonic cortisol in healthy volunteers simulating manned flight to Mars. Int J Psychophysiol 2014; 93:211-9. [DOI: 10.1016/j.ijpsycho.2014.04.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 04/05/2014] [Accepted: 04/24/2014] [Indexed: 10/25/2022]
|
17
|
Laurino M, Menicucci D, Piarulli A, Mastorci F, Bedini R, Allegrini P, Gemignani A. Disentangling different functional roles of evoked K-complex components: Mapping the sleeping brain while quenching sensory processing. Neuroimage 2014; 86:433-45. [DOI: 10.1016/j.neuroimage.2013.10.030] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 10/16/2013] [Accepted: 10/17/2013] [Indexed: 10/26/2022] Open
|