Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.215
Filtrar
1.
PLoS One ; 16(10): e0257738, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34614021

RESUMO

The phenomenon of dreaming about the laboratory when participating in a sleep study is common. The content of such dreams draws upon episodic memory fragments of the participant's lab experience, generally, experimenters, electrodes, the lab setting, and experimental tasks. However, as common as such dreams are, they have rarely been given a thorough quantitative or qualitative treatment. Here we assessed 528 dreams (N = 343 participants) collected in a Montreal sleep lab to 1) evaluate state and trait factors related to such dreams, and 2) investigate the phenomenology of lab incorporations using a new scoring system. Lab incorporations occurred in over a third (35.8%) of all dreams and were especially likely to occur in REM sleep (44.2%) or from morning naps (48.4%). They tended to be related to higher depression scores, but not to sex, nightmare-proneness or anxiety. Common themes associated with lab incorporation were: Meta-dreaming, including lucid dreams and false awakenings (40.7%), Sensory incorporations (27%), Wayfinding to, from or within the lab (24.3%), Sleep as performance (19.6%), Friends/Family in the lab (15.9%) and Being an object of observation (12.2%). Finally, 31.7% of the lab incorporation dreams included relative projections into a near future (e.g., the experiment having been completed), but very few projections into the past (2.6%). Results clarify sleep stage and sleep timing factors associated with dreamed lab incorporations. Phenomenological findings further reveal both the typical and unique ways in which lab memory elements are incorporated de novo into dreaming. Identified themes point to frequent social and skillful dream scenarios that entail monitoring of one's current state (in the lab) and projection of the self into dream environments elaborated around local space and time. The findings have implications for understanding fundamental dream formation mechanisms but also for appreciating both the advantages and methodological pitfalls of conducting laboratory-based dream collection.


Assuntos
Sonhos/fisiologia , Fases do Sono/fisiologia , Sono REM/fisiologia , Sono/fisiologia , Adulto , Feminino , Humanos , Laboratórios , Masculino , Memória Episódica , Rememoração Mental/fisiologia , Polissonografia , Adulto Jovem
4.
Biomed Res Int ; 2021: 5561974, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34350292

RESUMO

Early identification and diagnosis of mild cognitive impairment (MCI) in patients with parkinsonism (PDS) are critical. The aim of this study was to identify biomarkers of MCI in PDS using conventional electroencephalogram (EEG) power spectral analysis and detrended fluctuation analysis (DFA). In this retrospective study, patients with PDS who underwent an overnight polysomnography (PSG) study in our hospital from 2019 to 2020 were enrolled. Patients with PDS assessed by clinical examination and questionnaires were divided into two groups: the PDS with normal cognitive function (PDS-NC) group and the PDS with MCI (PDS-MCI) group. Sleep EEG signals were extracted and purified from the PSG and subjected to a conventional power spectral analysis, as well as detrended fluctuation analysis (DFA) during wakefulness, nonrapid eye movement (NREM) sleep, and rapid eye movement (REM) sleep. Forty patients with PDS were enrolled, including 25 with PDS-NC and 15 with PDS-MCI. Results revealed that compared with PDS-NC patients, patients with PDS-MCI had a reduced fast ratio ((alpha + beta)/(delta + theta)) and increased DFA during NREM sleep. DFA during NREM was diagnostic of PDS-MCI, with an area under the receiver operating characteristic curve of 0.753 (95% CI: 0.592-0.914) (p < 0.05). Mild cognitive dysfunction was positively correlated with NREM-DFA (r = 0.426, p = 0.007) and negatively correlated with an NREM-fast ratio (r = -0.524, p = 0.001). This suggested that altered EEG activity during NREM sleep is associated with MCI in patients with PDS. NREM sleep EEG characteristics of the power spectral analysis and DFA correlate to MCI. Slowing of EEG activity during NREM sleep may reflect contribution to the decline in NREM physiological function and is therefore a marker in patients with PDS-MCI.


Assuntos
Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Eletroencefalografia , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/fisiopatologia , Fases do Sono/fisiologia , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Estudos de Casos e Controles , Disfunção Cognitiva/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Parkinsonianos/complicações , Polissonografia , Curva ROC , Vigília/fisiologia
5.
Clin Geriatr Med ; 37(3): 417-427, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34210447

RESUMO

As in other adults, continuous positive airway pressure treatment for obstructive sleep apnea should be the mainstay of treatment. Benefits include improvements in sleepiness and quality of life, as well as improvements in hypertension control, arrhythmias, cardiovascular risk, and mortality. This article discusses issues in prescribing this treatment, including those related specifically to elderly individuals.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Qualidade de Vida , Apneia Obstrutiva do Sono/terapia , Idoso , Humanos , Fases do Sono/fisiologia , Resultado do Tratamento
6.
Commun Biol ; 4(1): 854, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244598

RESUMO

Current state-of-the-art functional magnetic resonance imaging (fMRI) offers remarkable imaging quality and resolution, yet, the intrinsic dimensionality of brain dynamics in different states (wakefulness, light and deep sleep) remains unknown. Here we present a method to reveal the low dimensional intrinsic manifold underlying human brain dynamics, which is invariant of the high dimensional spatio-temporal representation of the neuroimaging technology. By applying this intrinsic manifold framework to fMRI data acquired in wakefulness and sleep, we reveal the nonlinear differences between wakefulness and three different sleep stages, and successfully decode these different brain states with a mean accuracy across participants of 96%. Remarkably, a further group analysis shows that the intrinsic manifolds of all participants share a common topology. Overall, our results reveal the intrinsic manifold underlying the spatiotemporal dynamics of brain activity and demonstrate how this manifold enables the decoding of different brain states such as wakefulness and various sleep stages.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiologia , Sono/fisiologia , Vigília/fisiologia , Algoritmos , Encéfalo/diagnóstico por imagem , Eletroencefalografia/métodos , Humanos , Modelos Neurológicos , Rede Nervosa/diagnóstico por imagem , Neuroimagem/métodos , Fases do Sono/fisiologia
7.
Clin Neurophysiol ; 132(9): 2012-2018, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34284235

RESUMO

OBJECTIVE: We demonstrate that multifrequency entropy gives insight into the relationship between epileptogenicity and sleep, and forms the basis for an improved measure of medical assessment of sleep impairment in epilepsy patients. METHODS: Multifrequency entropy was computed from electroencephalography measurements taken from 31 children with Benign Epilepsy with Centrotemporal Spikes and 31 non-epileptic controls while awake and during sleep. Values were compared in the epileptic zone and away from the epileptic zone in various sleep stages. RESULTS: We find that (I) in lower frequencies, multifrequency entropy decreases during non-rapid eye movement sleep stages when compared with wakefulness in a general population of pediatric patients, (II) patients with Benign Epilepsy with Centrotemporal Spikes had lower multifrequency entropy across stages of sleep and wakefulness, and (III) the epileptic regions of the brain exhibit lower multifrequency entropy patterns than the rest of the brain in epilepsy patients. CONCLUSIONS: Our results show that multifrequency entropy decreases during sleep, particularly sleep stage 2, confirming, in a pediatric population, an association between sleep, lower multifrequency entropy, and increased likelihood of seizure. SIGNIFICANCE: We observed a correlation between lowered multifrequency entropy and increased epileptogenicity that lays preliminary groundwork for the detection of a digital biomarker for epileptogenicity.


Assuntos
Ondas Encefálicas/fisiologia , Eletroencefalografia/métodos , Entropia , Epilepsia Rolândica/diagnóstico , Epilepsia Rolândica/fisiopatologia , Fases do Sono/fisiologia , Potenciais de Ação/fisiologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos
8.
Commun Biol ; 4(1): 722, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117351

RESUMO

Understanding human sleep requires appropriate animal models. Sleep has been extensively studied in rodents, although rodent sleep differs substantially from human sleep. Here we investigate sleep in tree shrews, small diurnal mammals phylogenetically close to primates, and compare it to sleep in rats and humans using electrophysiological recordings from frontal cortex of each species. Tree shrews exhibited consolidated sleep, with a sleep bout duration parameter, τ, uncharacteristically high for a small mammal, and differing substantially from the sleep of rodents that is often punctuated by wakefulness. Two NREM sleep stages were observed in tree shrews: NREM, characterized by high delta waves and spindles, and an intermediate stage (IS-NREM) occurring on NREM to REM transitions and consisting of intermediate delta waves with concomitant theta-alpha activity. While IS-NREM activity was reliable in tree shrews, we could also detect it in human EEG data, on a subset of transitions. Finally, coupling events between sleep spindles and slow waves clustered near the beginning of the sleep period in tree shrews, paralleling humans, whereas they were more evenly distributed in rats. Our results suggest considerable homology of sleep structure between humans and tree shrews despite the large difference in body mass between these species.


Assuntos
Sono/fisiologia , Tupaiidae/fisiologia , Animais , Eletroencefalografia , Feminino , Lobo Frontal/fisiologia , Humanos , Masculino , Ratos , Ratos Long-Evans/fisiologia , Fases do Sono/fisiologia , Sono REM/fisiologia , Adulto Jovem
9.
Clin Neurophysiol ; 132(8): 1757-1769, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34130242

RESUMO

Since the term Stimulus-Induced Rhythmic, Periodic, or Ictal Discharges (SIRPIDs) was introduced into the vocabulary of electrophysiologists/neurologists, there has been an ongoing debate about its significance, as well as its correlation with outcomes. SIRPIDs are frequently seen in patients who are critically ill from various causes. The literature reflects the findings of triphasic morphology, with the generalized periodic discharge (GPD) classification in many patients with SIRPIDs: toxic/metabolic encephalopathies, septic, and hypoxemic/hypercapnic encephalopathies, but also sharp periodic complexes in Creutzfeldt-Jakob disease and advanced Alzheimer's disease. In these settings, GPDs disappear when patients fall asleep and reappear when patients spontaneously wake up, or are awoken by an external stimulus, or sometimes because of a respiratory event, with the possibility of the appearance of GPDs with a cyclic alternating pattern. SIRPIDs may be seen as a transitional pattern between sleep and waking states, corresponding to a postarousal/awakening phenomenon. As SIRPIDs are a transient phenomenon and can usually be recorded repeatedly with each stimulation, the word "Ictal" could be replaced by "Intermittent": Stimulus-Induced Rhythmic or Periodic Intermittent Discharges. However, considering that SIRPIDs may be "potentially ictal" or on an "ictal-interictal continuum" in some situations, the "plus" modifier may be added: SIRPIDs-plus.


Assuntos
Ondas Encefálicas/fisiologia , Encéfalo/fisiopatologia , Síndrome de Creutzfeldt-Jakob/fisiopatologia , Periodicidade , Fases do Sono/fisiologia , Vigília/fisiologia , Encéfalo/diagnóstico por imagem , Síndrome de Creutzfeldt-Jakob/diagnóstico por imagem , Eletroencefalografia/métodos , Humanos
10.
Neuroimage ; 239: 118281, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34147627

RESUMO

Plasticity of synaptic strength and density is a vital mechanism enabling memory consolidation, learning, and neurodevelopment. It is strongly dependent on the intact function of N-Methyl-d-Aspartate Receptors (NMDAR). The importance of NMDAR is further evident as their dysfunction is involved in many diseases such as schizophrenia, Alzheimer's disease, neurodevelopmental disorders, and epilepsies. Synaptic plasticity is thought to be reflected by changes of sleep slow wave slopes across the night, namely higher slopes after wakefulness at the beginning of sleep than after a night of sleep. Hence, a functional NMDAR deficiency should theoretically lead to altered overnight changes of slow wave slopes. Here we investigated whether pediatric patients with anti-NMDAR encephalitis, being a very rare but unique human model of NMDAR deficiency due to autoantibodies against receptor subunits, indeed show alterations in this sleep EEG marker for synaptic plasticity. We retrospectively analyzed 12 whole-night EEGs of 9 patients (age 4.3-20.8 years, 7 females) and compared them to a control group of 45 healthy individuals with the same age distribution. Slow wave slopes were calculated for the first and last hour of Non-Rapid Eye Movement (NREM) sleep (factor 'hour') for patients and controls (factor 'group'). There was a significant interaction between 'hour' and 'group' (p = 0.013), with patients showing a smaller overnight decrease of slow wave slopes than controls. Moreover, we found smaller slopes during the first hour in patients (p = 0.022), whereas there was no group difference during the last hour of NREM sleep (p = 0.980). Importantly, the distribution of sleep stages was not different between the groups, and in our main analyses of patients without severe disturbance of sleep architecture, neither was the incidence of slow waves. These possible confounders could therefore not account for the differences in the slow wave slope values, which we also saw in the analysis of the whole sample of EEGs. These results suggest that quantitative EEG analysis of slow wave characteristics may reveal impaired synaptic plasticity in patients with anti-NMDAR encephalitis, a human model of functional NMDAR deficiency. Thus, in the future, the changes of sleep slow wave slopes may contribute to the development of electrophysiological biomarkers of functional NMDAR deficiency and synaptic plasticity in general.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/fisiopatologia , Ondas Encefálicas/fisiologia , Eletroencefalografia/métodos , Plasticidade Neuronal , Receptores de N-Metil-D-Aspartato/deficiência , Fases do Sono/fisiologia , Adolescente , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Receptores de N-Metil-D-Aspartato/imunologia , Estudos Retrospectivos , Adulto Jovem
11.
PLoS One ; 16(6): e0253376, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34138961

RESUMO

Previous research shows that female athletes sleep better according to objective parameters but report worse subjective sleep quality than male athletes. However, existing sleep studies did not investigate variations in sleep and sleep stages over longer periods and have, so far, not elucidated the role of the menstrual cycle in female athletes' sleep. To address these methodological shortcomings, we investigated sex differences in sleep and sleep stages over 61 continuous days in 37 men and 19 women and examined the role of the menstrual cycle and its phases in 15 women. Sleep was measured by a non-contact radar, and menstrual bleeding was self-reported. Associations were investigated with multilevel modeling. Overall, women tended to report poorer subjective sleep quality (p = .057), but objective measurements showed that women obtained longer sleep duration (p < .001), more light (p = .013) and rapid eye movement sleep (REM; hours (h): p < .001, %: p = .007), shorter REM latency (p < .001), and higher sleep efficiency (p = .003) than men. R2 values showed that sleep duration, REM and REM latency were especially affected by sex. Among women, we found longer time in bed (p = .027) and deep sleep (h: p = .036), and shorter light sleep (%: p = .021) during menstrual bleeding vs. non-bleeding days; less light sleep (h: p = .040), deep sleep (%: p = .013) and shorter REM latency (p = .011) during the menstrual than pre-menstrual phase; and lower sleep efficiency (p = .042) and more deep sleep (%: p = .026) during the follicular than luteal phase. These findings indicate that the menstrual cycle may impact the need for physiological recovery, as evidenced by the sleep stage variations. Altogether, the observed sex differences in subjective and objective sleep parameters may be related to the female athletes' menstrual cycle. The paper provides unique data of sex differences in sleep stages and novel insights into the role of the menstrual cycle in sleep among female athletes.


Assuntos
Atletas , Ciclo Menstrual/fisiologia , Fases do Sono/fisiologia , Sono/fisiologia , Adolescente , Ritmo Circadiano/fisiologia , Feminino , Humanos , Masculino , Caracteres Sexuais , Vigília/fisiologia
12.
Clin Neurophysiol ; 132(7): 1550-1563, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34034085

RESUMO

OBJECTIVE: We recently proposed a spectrum-based model of the awake intracranial electroencephalogram (iEEG) (Kalamangalam et al., 2020), based on a publicly-available normative database (Frauscher et al., 2018). The latter has been expanded to include data from non-rapid eye movement (NREM) and rapid eye movement (REM) sleep (von Ellenrieder et al., 2020), and the present work extends our methods to those data. METHODS: Normalized amplitude spectra on semi-logarithmic axes from all four arousal states (wake, N2, N3 and REM) were averaged region-wise and fitted to a multi-component Gaussian distribution. A reduced model comprising five key parameters per brain region was color-coded on to cortical surface models. RESULTS: The lognormal Gaussian mixture model described the iEEG accurately from all brain regions, in all sleep-wake states. There was smooth variation in model parameters as sleep and wake states yielded to each other. Specific observations unrelated to the model were that the primary cortical areas of vision, motor function and audition, in addition to the hippocampus, did not participate in the 'awakening' of the cortex during REM sleep. CONCLUSIONS: Despite the significant differences in the appearance of the time-domain EEG in wakefulness and sleep, the iEEG in all arousal states was successfully described by a parametric spectral model of low dimension. SIGNIFICANCE: Spectral variation in the iEEG is continuous in space (across different cortical regions) and time (stage of circadian cycle), arguing for a 'continuum' hypothesis in the generative processes of sleep and wakefulness in human brain.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Eletroencefalografia/métodos , Redes Neurais de Computação , Fases do Sono/fisiologia , Vigília/fisiologia , Bases de Dados Factuais , Humanos , Distribuição Normal
13.
Exp Neurol ; 343: 113760, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34000248

RESUMO

General anesthetic agents are thought to induce loss-of-consciousness (LOC) and enable pain-free surgery by acting on the endogenous brain circuitry responsible for sleep-wake cycling. In clinical use, the entire CNS is exposed to anesthetic molecules with LOC and amnesia usually attributed to synaptic suppression in the cerebral cortex and immobility and analgesia to agent action in the spinal cord and brainstem. This model of patch-wise suppression has been challenged, however, by the observation that all functional components of anesthesia can be induced by focal delivery of minute quantities of GABAergic agonists to the brainstem mesopontine tegmental anesthesia area (MPTA). We compared spectral features of the cortical electroencephalogram (EEG) in rats during systemic anesthesia and anesthesia induced by MPTA microinjection. Systemic administration of (GABAergic) pentobarbital yielded the sustained, δ-band dominant EEG signature familiar in clinical anesthesia. In contrast, anesthesia induced by MPTA microinjection (pentobarbital or muscimol) featured epochs of δ-band EEG alternating with the wake-like EEG, the pattern typical of natural non-rapid-eye-movement (NREM) and REM sleep. The rats were not sleeping, however, as they remained immobile, atonic and unresponsive to noxious pinch. Recalling the paradoxical wake-like quality the EEG during REM sleep, we refer to this state as "paradoxical anesthesia". GABAergic anesthetics appear to co-opt both cortical and spinal components of the sleep network via dedicated axonal pathways driven by MPTA neurons. Direct drug exposure of cortical and spinal neurons is not necessary, and is probably responsible for off-target side-effects of systemic administration including monotonous δ-band EEG, hypothermia and respiratory depression. SIGNIFICANCE STATEMENT: The concept that GABAergic general anesthetic agents induce loss-of-consciousness by substituting for an endogenous neurotransmitter, thereby co-opting neural circuitry responsible for sleep-wake transitions, has gained considerable traction. However, the electroencephalographic (EEG) signatures of sleep and anesthesia differ fundamentally. We show that when the anesthetic state is generated by focal delivery of GABAergics into the mesopontine tegmental anesthesia area (MPTA) the resulting EEG repeatedly transitions between delta-wave-dominant and wake-like patterns much as in REM-NREM sleep. This suggests that systemic (clinical) anesthetic delivery, which indiscriminately floods the entire cerebrum with powerful inhibitory agents, obscures the sleep-like EEG signature associated with the less adulterated form of anesthesia obtained when the drugs are applied selectively to loci where the effective neurotransmitter substitution actually occurs.


Assuntos
Anestesia/métodos , Tronco Encefálico/efeitos dos fármacos , Eletroencefalografia/efeitos dos fármacos , GABAérgicos/administração & dosagem , Microinjeções/métodos , Fases do Sono/efeitos dos fármacos , Animais , Tronco Encefálico/fisiologia , Eletroencefalografia/métodos , Feminino , Masculino , Ratos , Ratos Wistar , Reflexo de Endireitamento/efeitos dos fármacos , Reflexo de Endireitamento/fisiologia , Fases do Sono/fisiologia
14.
Sci Rep ; 11(1): 9970, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976280

RESUMO

Using large-scale objective sleep data derived from body acceleration signals of 68,604 Japanese residents ranging from adolescents to the elderly (10-89 years old), we found significant age- and gender-related differences in sleep properties (timing, duration, and quality) in real-life settings. Time-in-bed and total sleep time (TST) showed a U-shaped association with age, indicating their decrease in adulthood following their increase in the elderly. There was a remarkable shift in sleep phase toward earlier bedtime and earlier wake time with increasing age (> 20 years), together with worsening of sleep quality, which is estimated by sleep efficiency (SE) and wake time after sleep onset. Gender comparisons showed that TST was shorter in women than in similarly aged men, which is much evident after the age of 30 years. This was associated with later bedtimes and greater age-related deterioration of sleep quality in women. Compared to men in the same age group, women over age 50 demonstrated a greater reduction in SE with aging, due mainly to increasing durations of nighttime awakening. These differences can be attributed to several intricately intertwined causes, including biological aging as well as socio-cultural and socio-familial factors in Japan. In conclusion, our findings provide valuable insights on the characteristics of Japanese sleep habits.


Assuntos
Sono/genética , Sono/fisiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Criança , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Polissonografia/métodos , Caracteres Sexuais , Fatores Sexuais , Fases do Sono/fisiologia , Inquéritos e Questionários
15.
Front Neurol Neurosci ; 45: 103-116, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34052809

RESUMO

Since its description in the 19th century, narcolepsy type 1 (NT1) has been considered as a model sleep disorder, and after the discovery of rapid eye movement (REM) sleep onset in the disorder, a gateway to understanding REM sleep. The discovery that NT1 is caused by hypocretin/orexin deficiency, together with neurochemical studies of this system, has helped to establish how this neuropeptide regulates the organization of sleep and wake in humans. Current analyses suggest that the main functions of the hypocretin/orexin system are (1) maintenance of wakefulness in the face of moderate sleep deprivation; (2) passive wake promotion, especially in the evening, driven by the circadian clock; (3) inhibition of REM sleep, with possible differential modulating effects on various subcomponents of the sleep-stage, explaining REM sleep dissociation events in NT1. Narcolepsy is also associated with an inability to consolidate sleep, a more complex phenotype that may result from secondary changes or be central to the role of hypocretin in coordinating the activity of other sleep- and wake-promoting systems. Novel technologies, such as the use of deep learning analysis of electroencephalographic signals, is revealing a complex pattern of sleep abnormalities in human narcolepsy that can be used diagnostically. The availability of novel devices measuring sleep 24 h per day also holds promise to provide new insights into how brain electrical activity and muscle tone are regulated by hypocretin.


Assuntos
Narcolepsia/metabolismo , Narcolepsia/fisiopatologia , Orexinas/deficiência , Fases do Sono/fisiologia , Humanos
16.
Sci Rep ; 11(1): 11151, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045518

RESUMO

We developed a real-time sleep stage classification system with a convolutional neural network using only a one-channel electro-encephalogram source from mice and universally available features in any time-series data: raw signal, spectrum, and zeitgeber time. To accommodate historical information from each subject, we included a long short-term memory recurrent neural network in combination with the universal features. The resulting system (UTSN-L) achieved 90% overall accuracy and 81% multi-class Matthews Correlation Coefficient, with particularly high-quality judgements for rapid eye movement sleep (91% sensitivity and 98% specificity). This system can enable automatic real-time interventions during rapid eye movement sleep, which has been difficult due to its relatively low abundance and short duration. Further, it eliminates the need for ordinal pre-calibration, electromyogram recording, and manual classification and thus is scalable. The code is open-source with a graphical user interface and closed feedback loop capability, making it easily adaptable to a wide variety of end-user needs. By allowing large-scale, automatic, and real-time sleep stage-specific interventions, this system can aid further investigations of the functions of sleep and the development of new therapeutic strategies for sleep-related disorders.


Assuntos
Redes Neurais de Computação , Processamento de Sinais Assistido por Computador , Fases do Sono/fisiologia , Músculos Superficiais do Dorso/fisiologia , Algoritmos , Animais , Eletrodos , Eletroencefalografia , Eletromiografia , Camundongos
17.
J Clin Neurophysiol ; 38(2): 87-91, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33661784

RESUMO

SUMMARY: Recording of interictal epileptiform discharges to classify the epilepsy syndrome is one of the most common indications for ambulatory EEG. Ambulatory EEG has superior sampling compared with standard EEG recordings and advantages in terms of cost-effectiveness and convenience compared with a prolonged inpatient EEG study. Ambulatory EEG allows for EEG recording in all sleep stages and transitional states, which can be very helpful in capturing interictal epileptiform discharges. In the absence of interictal epileptiform discharges or in patients with atypical events, the characterization of an epilepsy syndrome may require recording of the habitual events. Diagnostic ambulatory EEG can be a useful alternative to inpatient video-EEG monitoring in a selected number of patients with frequent events who do not require medication taper or seizure testing for surgical localization.


Assuntos
Eletroencefalografia/classificação , Eletroencefalografia/métodos , Síndromes Epilépticas/classificação , Síndromes Epilépticas/diagnóstico , Monitorização Ambulatorial/classificação , Monitorização Ambulatorial/métodos , Adulto , Análise Custo-Benefício , Síndromes Epilépticas/fisiopatologia , Feminino , Humanos , Masculino , Convulsões/classificação , Convulsões/diagnóstico , Convulsões/fisiopatologia , Fases do Sono/fisiologia
18.
J Neurosci ; 41(18): 4088-4099, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33741722

RESUMO

Sleep has been shown to be critical for memory consolidation, with some research suggesting that certain memories are prioritized for consolidation. Initial strength of a memory appears to be an important boundary condition in determining which memories are consolidated during sleep. However, the role of consolidation-mediating oscillations, such as sleep spindles and slow oscillations, in this preferential consolidation has not been explored. Here, 54 human participants (76% female) studied pairs of words to three distinct encoding strengths, with recall being tested immediately following learning and again 6 h later. Thirty-six had a 2 h nap opportunity following learning, while the remaining 18 remained awake throughout. Results showed that, across 6 h awake, weakly encoded memories deteriorated the fastest. In the nap group, however, this effect was attenuated, with forgetting rates equivalent across encoding strengths. Within the nap group, consolidation of weakly encoded items was associated with fast sleep spindle density during non-rapid eye movement sleep. Moreover, sleep spindles that were coupled to slow oscillations predicted the consolidation of weak memories independently of uncoupled sleep spindles. These relationships were unique to weakly encoded items, with spindles not correlating with memory for intermediate or strong items. This suggests that sleep spindles facilitate memory consolidation, guided in part by memory strength.SIGNIFICANCE STATEMENT Given the countless pieces of information we encode each day, how does the brain select which memories to commit to long-term storage? Sleep is known to aid in memory consolidation, and it appears that certain memories are prioritized to receive this benefit. Here, we found that, compared with staying awake, sleep was associated with better memory for weakly encoded information. This suggests that sleep helps attenuate the forgetting of weak memory traces. Fast sleep spindles, a hallmark oscillation of non-rapid eye movement sleep, mediate consolidation processes. We extend this to show that fast spindles were uniquely associated with the consolidation of weakly encoded memories. This provides new evidence for preferential sleep-based consolidation and elucidates a physiological correlate of this benefit.


Assuntos
Consolidação da Memória/fisiologia , Memória/fisiologia , Fases do Sono/fisiologia , Eletroencefalografia , Feminino , Humanos , Aprendizagem/fisiologia , Masculino , Rememoração Mental , Desempenho Psicomotor/fisiologia , Sono/fisiologia , Sono de Ondas Lentas/fisiologia , Vigília , Adulto Jovem
19.
J Neurosci ; 41(19): 4253-4261, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33785642

RESUMO

Sleep spindles are intermittent bursts of 11-15 Hz EEG waves that occur during non-rapid eye movement sleep. Spindles are believed to help maintain sleep and to play a role in sleep-dependent memory consolidation. Here we applied an automated sleep spindle detection program to our large longitudinal sleep EEG dataset (98 human subjects, 6-18 years old, >2000 uninterrupted nights) to evaluate maturational trends in spindle wave frequency, density, amplitude, and duration. This large dataset enabled us to apply nonlinear as well as linear age models, thereby extending the findings of prior cross-sectional studies that used linear models. We found that spindle wave frequency increased with remarkable linearity across the age range. Central spindle density increased nonlinearly to a peak at age 15.1 years. Central spindle wave amplitude declined in a sigmoidal pattern with the age of fastest decline at 13.5 years. Spindle duration decreased linearly with age. Of the four measures, only spindle amplitude showed a sex difference in dynamics such that the age of most rapid decline in females preceded that in males by 1.4 years. This amplitude pattern, including the sex difference in timing, paralleled the maturational pattern for δ (1-4 Hz) wave power. We interpret these age-related changes in spindle characteristics as indicators of maturation of thalamocortical circuits and changes in sleep depth. These robust age-effects could facilitate the search for cognitive-behavioral correlates of spindle waveforms and might also help guide basic research on EEG mechanisms and postnatal brain maturation.SIGNIFICANCE STATEMENT The brain reorganization of adolescence produces massive changes in sleep EEG. These changes include the morphology and abundance of sleep spindles, an EEG marker of non-rapid eye movement sleep believed to reflect offline memory processes and/or protection of the sleep state. We analyzed >2000 nights of longitudinal sleep EEG from 98 subjects (age 6-18 years old) to investigate maturational changes in spindle amplitude, frequency, density, and duration. The large dataset enabled us to detect nonlinear as well as linear age changes. All measures showed robust age effects that we hypothesize reflect the maturation of thalamocortical circuits and decreasing sleep depth. These findings could guide further research into the cognitive-behavioral correlates of sleep spindles and their underlying brain mechanisms.


Assuntos
Envelhecimento/fisiologia , Fases do Sono/fisiologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Eletroencefalografia , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Consolidação da Memória , Polissonografia , Caracteres Sexuais
20.
PLoS One ; 16(1): e0243743, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33406143

RESUMO

Sleep is intimately linked to cognitive performance and exposure to traumatic stress that leads to post-traumatic stress disorder (PTSD) impairs both sleep and cognitive function. However, the contribution of pre-trauma sleep loss to subsequent trauma-dependent fear-associated memory impairment remains unstudied. We hypothesized that sleep deprivation (SD) prior to trauma exposure may increase the severity of a PTSD-like phenotype in rats exposed to single prolonged stress (SPS), a rodent model of PTSD. Rats were exposed to SPS alone, SD alone, or a combination of SPS+SD and measures of fear-associated memory impairments and vigilance state changes were compared to a group of control animals not exposed to SPS or SD. We found that SPS, and SPS+SD animals showed impaired fear-associated memory processing and that the addition of SD to SPS did not further exaggerate the effect of SPS alone. Additionally, the combination of SPS with SD results in a unique homeostatic sleep duration phenotype when compared to SD, SPS, or control animals. SPS exposure following SD represses homeostatic rebound and eliminates sleep-deprivation-induced increases in NREM sleep delta power. This work identifies a unique time frame where trauma exposure and sleep interact and identifies this window of time as a potential therapeutic treatment window for staving off the negative consequences of trauma exposure.


Assuntos
Progressão da Doença , Medo/psicologia , Transtornos da Memória/psicologia , Índice de Gravidade de Doença , Privação do Sono/psicologia , Sono/fisiologia , Estresse Psicológico/fisiopatologia , Ferimentos e Lesões/psicologia , Animais , Extinção Psicológica , Homeostase , Masculino , Transtornos da Memória/complicações , Transtornos da Memória/fisiopatologia , Rememoração Mental , Ratos Long-Evans , Privação do Sono/complicações , Fases do Sono/fisiologia , Estresse Psicológico/complicações
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...