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Róbert Bódizs

Semmelweis University, Institute of Behavioural Sciences, Faculty Member

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I am a research psychologist interested in the psychophysiological and neural mechanisms of sleep regulation. He was a student of Babes-Bolyai University Cluj-Napoca (1992-1997) and obtained his PhD degree (2002) and habilitation (2014) at the Semmelweis University, Budapest in Neuroscience/Theoretical Medicine and Medical Psychology, respectively. Currently he is a Senior research fellow and Deputy Research Director of the Institute of Behavioural Sciences, Semmelweis University Budapest. He conducted and published several research works on the electrophysiological, cognitive and affective aspects of sleep, including the sleep-related biomarkers of intelligence, typical and atypical developmental tarjectories as reflected in sleep, aging and sleep, as well as of dreaming and nightmares. He is the founder and the Editor-in-Chief of Sleep Spindles

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Papers by Róbert Bódizs

P370 The thalamo-cortical generators of sleep spindles as revealed by laminar analysis of neocortex

Clinical Neurophysiology, Sep 1, 2017

syndrome, respectively. Long segments (>5 min) of GPi-LFP recordings at rest were selected from e... more syndrome, respectively. Long segments (>5 min) of GPi-LFP recordings at rest were selected from each patient (in PD patients, ''on" and ''off" medication). Results: The two PD patients had low-beta, high-beta and HFO peaks in the ''off" power spectrum. In the ''on" state, the low-beta peak attenuated and the HFO peaks changed in frequency and power, as expected. The patients with dystonia showed theta and high-beta peaks. However, either no HFO peak or a much smaller one (in only two patients) was observed. The two patients with chorea had high-beta and HFO peaks only. The patients with Tourette's síndrome had no evident beta peaks, but HFO activity was very evident. Conclusions: The activity observed in PD patients in the GPi is similar to that observed in the STN, including the presence of HFOs. HFOs are also observed in patients with chorea or Tourette's syndrome, but might be absent or smaller in patients with dystonia. Beta peaks were absent in the two patients with Tourette's syndrome. Significance: The GPi and STN show similar oscillatory activity in PD, including HFOs. Different neurologic diseases are associtated with different oscillatory activities in the GPi.

Az alvás szerkezete és mintázatai autizmus spektrumzavarban

Psychiatria Hungarica : A Magyar Pszichiátriai Társaság tudományos folyóirata, 2008

Human sleep, as an ancient demeanor emerging at the meeting-point of psychogenetic and ontogeneti... more Human sleep, as an ancient demeanor emerging at the meeting-point of psychogenetic and ontogenetic brain development as well as of specific environmental factors, frames the basis of adaptation to complex information processing conditions. Therefore sleep befalls in the focus of modern sleep research as the sensitive indicator of psychological and biological integrity. Autism spectrum disorders (ASD) are characterized by peculiarly altered behaviours occurring in various life situations, which can be traced in the structure and patterns of sleep as well. There is convincing evidence suggesting that ASD are associated with various sleep disorders at times of extreme severity. The frequency of these sleep disorders is different from those seen in typically developing children of the same age and mental abilities, but often overlapping with other neuropsychiatric disorders. The present article while reviewing core methodological milestones of sleep research provides an extensive overview of the nature of sleep disorders emerging in ASD as well as of the composite relationships between psychological and physiological features. Emerging knowledge regarding the etiological background and treatment options will be also addressed.

Dreaming and dream amnesia in the light of reactive and predictive homeostasis

Dreams are often viewed as fascinating but relatively irrelevant mental epihenomena of the sleepi... more Dreams are often viewed as fascinating but relatively irrelevant mental epihenomena of the sleeping mind with questionable or no functional relevance. Despite long hours of oneiric activity, and high individual differences in dream recall, dream amnesia is one of the most robust and universal features of dreaming. In this review, we conceptualize dreaming and dream amnesia as inherent aspects of the homeostatic functions of sleep and wakefulness. In this framework the temporal progression of sleep throughout the night is shaped by reactive and predictive homeostatic functions. Mental activity during sleep conforms to the dynamic interplay of restorative processes and future anticipation, and particularly during the second half of the night, unfolds as a special form of non-constrained, self-referent, and future-oriented cognitive process. Awakening facilitates constrained, goal-directed prospection that competes for shared neural resources with dream production and dream recall, and hence, contributes to dream amnesia. We present the neurophysiological aspects of reactive and predictive homeostasis during sleep, highlighting the putative role of nocturnal cortisol as well as the cortisol awakening response in predictive homeostasis and dream amnesia, respectively. The theoretical and methodological aspect of our proposal is discussed in relation to the study of dream recall, sleep-related cognitive processes and altered dreaming in sleep disorders.

Comparing manual and automatic artifact detection in sleep EEG recordings

bioRxiv (Cold Spring Harbor Laboratory), May 14, 2023

Daily rhythms, demographics and health: findings from a nationally representative survey

bioRxiv (Cold Spring Harbor Laboratory), Apr 9, 2023

Fractal cycles of sleep: a new aperiodic activity-based definition of sleep cycles

bioRxiv (Cold Spring Harbor Laboratory), Jul 4, 2023

Sleep time, social jetlag and intelligence: biology or work timing?

A questionnaire measure of adult attachment anxiety correlates with frontal hemispheric asymmetry in sleep spindle activity

Sleep and Biological Rhythms, Oct 20, 2022

Subjects with high levels of attachment anxiety and neuroticism were proposed to be characterized... more Subjects with high levels of attachment anxiety and neuroticism were proposed to be characterized by higher relative right rather than left frontal activity. Since sleep spindles are argued to reflect enhanced offline neuroplasticity, higher spindle activity measured over the right frontal areas relative to the corresponding left frontal ones could index higher attachment anxiety and neuroticism. Our aim was to explore the relationship between the lateralization patterns of frontally dominant slow sleep spindles and questionnaire measures of adult attachment anxiety and neuroticism. Thirty-four healthy subjects (male = 19; M age = 31.64; SD age = 9.5) were enrolled in our preliminary study. Second night EEG/polysomnography records and questionnaire measures of personality (Zuckerman-Kuhlman Personality Questionnaire) and adult attachment (Relationship Scales Questionnaire) were collected. Frontal slow sleep spindles were measured by the Individual Adjustment Method (IAM), whereas hemispheric asymmetry indexes of spindle occurrence rate, duration, and amplitude were derived as normalized left-right differences (electrode pairs: Fp1-Fp2, F3-F4, and F7-F8). Relative right lateralization of frontolateral and frontopolar slow sleep spindle density and mid-frontal slow spindle duration were associated with attachment anxiety, but spindle lateralization was less closely related to neuroticism. The relationships between frontal slow spindle laterality and attachment anxiety remained statistically significant even after controlling for the effect of neuroticism, whereas attachment avoidance-independence was not correlated with frontal slow spindle lateralization. Right frontal lateralization of slow sleep spindle activity might indicate attachment status in terms of the negative view of the self.

Hullámok nyelvén: a szerotonin és az alvási oszcillációk

A szerotonin és az alvás-ébrenlét állapotok szoros és komplex összefüggése rendkívüli elméleti és... more A szerotonin és az alvás-ébrenlét állapotok szoros és komplex összefüggése rendkívüli elméleti és gyakorlati jelentõségû kérdéskör. A probléma ellentmondásossága és a rendelkezésre álló szakirodalmi adatok fényében sem kellõképpen tisztázott jellege azonban nehezíti az e témakörrel kapcsolatos ismeretek rendszerezését és hasznosítását. A szerotonin alvásszabályozásban játszott szerepének áttekintése során kiemelt figyelmet szentelünk az akut ébresztõ és a hosszabb távon érvényesülõ, cirkadián fázist módosító illetve az alvás homeosztatikus szabályozását moduláló funkciók elkülönült elemzésének. A receptortípusok szerinti differenciált hatások szempontjából az 5-HT1A/7 és 5-HT3 receptorok cirkadián ritmicitást illetve REM alvást szabályozó/ moduláló, valamint az 5-HT2A receptoroknak az alvás homeosztázisában, az alvásintenzitásban, az ultradián alvásorganizációban és az alvás folyamatosságában játszott szerepei kerülnek a tanulmány elemzéseinek fókuszába. Ugyanakkor a szerotonin, a n...

Role of anterior thalamic circuitry during sleep

Epilepsy Research

Prolongation of cortical sleep spindles during hippocampal interictal epileptiform discharges in epilepsy patients

Epilepsia

ObjectiveMemory deficits are frequent among patients with epilepsies affecting the temporal lobe.... more ObjectiveMemory deficits are frequent among patients with epilepsies affecting the temporal lobe. Hippocampal interictal epileptic discharges (hIEDs), the presumed epileptic exaggeration of sharp wave‐ripples (SWRs), are known to contribute to memory dysfunction, but the potential underlying mechanism is unknown. The precise temporal coordination between hippocampal SWRs and corticothalamic spindles during sleep is critical for memory consolidation. Moreover, previous investigation indicated that hIEDs induce neocortical spindlelike oscillation. In the present study, we aimed to assess the influence of hIEDs on neocortical spindles.MethodsWe analyzed the spindle characteristics (duration, amplitude, frequency) of 21 epilepsy patients implanted with foramen ovale (FO) electrodes during a whole night sleep. Scalp sleep spindles were categorized based on their temporal relationship to hIEDs detected on the FO electrodes. Three groups were created: (1) spindles coinciding with hIEDs, (2...

Alvásszabályozás És Hipnotikumok: A Benzodiazepin-Receptor Agonisták Hatásai

As binding sites of the alpha-amino butyric acid receptor complexes benzodiazepine-receptors offe... more As binding sites of the alpha-amino butyric acid receptor complexes benzodiazepine-receptors offer a possibility to enhance hyperpolarization-based inhibition by allosteric modulation. Most of the hypnotic drugs are compounds that bind to benzodiazepine receptors. The effects of these drugs are usually characterized at a descriptive level, without deliberation of the basic processes involved in sleep regulation. This review follows the analysis of hypnotic's effect from a perspective of homeostatic, circadian, ultradian and microstructural regulation of sleep. In contrast to their expected effect benzodiazepines produce a decrease in most of the markers of homeostatic sleep regulation. Ligands with non-benzodiazepine structure (cyclopyrrolones, imidazopyridines, pyrazolopyrimidines) have a permissive or even stimulating effect in some measures of homeostatic sleep regulation. Some benzodiazepines have marked chronobiotic effects, while others interfere with circadian rhythms. Th...

Cortical monitoring of cardiac activity during rapid eye movement sleep: the heartbeat evoked potential in phasic and tonic rapid-eye-movement microstates

Sleep, 2021

Sleep is a fundamental physiological state that facilitates neural recovery during periods of att... more Sleep is a fundamental physiological state that facilitates neural recovery during periods of attenuated sensory processing. On the other hand, mammalian sleep is also characterized by the interplay between periods of increased sleep depth and environmental alertness. Whereas the heterogeneity of microstates during non-rapid-eye-movement (NREM) sleep was extensively studied in the last decades, transient microstates during rapid-eye-movement (REM) sleep received less attention. REM sleep features two distinct microstates: phasic and tonic. Previous studies indicate that sensory processing is largely diminished during phasic REM periods, whereas environmental alertness is partially reinstated when the brain switches into tonic REM sleep. Here, we investigated interoceptive processing as quantified by the heartbeat evoked potential (HEP) during REM microstates. We contrasted the HEPs of phasic and tonic REM periods using two separate databases that included the nighttime polysomnograp...

Morningness is associated with lower sleep spindle amplitudes and intensities during adolescence

Sleep Medicine, 2017

Introduction: Portable home sleep monitors are being increasingly utilized in clinical practice f... more Introduction: Portable home sleep monitors are being increasingly utilized in clinical practice for diagnosing sleep apnea. Most type III home monitors are difficult for patients to set up and wearing the monitors is disruptive to patient's typical sleep pattern. The diagnostic value of an inexpensive easy-to-use lightweight flexible skin-adhesive patch (Som-naPatch) that is non-disruptive to sleep was evaluated in this study. Materials and methods: Simultaneous polysomnography (PSG) and the diagnostic patch recordings were made in 179 subjects (mean age 54.0±13.6 y, 55% male) selected from the databases of patients previously tested with PSG to ensure even representation of the clinically important apnea-hypopnea index (AHI) ranges. The skin-adhesive diagnostic patch weighs less than one ounce and records nasal pressure, blood oxygen saturation, pulse rate, respiratory effort, sleep time and body position. To compare the apnea-hypopnea index of the diagnostic patch with polysomnography, the recordings were auto-scored with the Somnolyzer software (Respironics). Bland-Altman analysis was performed. Sensitivity, specificity and accuracy were calculated and receiver operating characteristic (ROC) curves were constructed for six AHI thresholds (5, 10, 15, 20, 25 and 30 events per hour). The rate of clinical agreement and positive likelihood ratio were calculated. Results: Overnight recordings from 174 subjects were included in the analysis. All six ROC curves had area under the curve of over 0.9. Sensitivity, specificity and accuracy for the optimal threshold of AHI15 were 0.86, 0.83 and 0.85 respectively. Positive likelihood ratio (LRþ) was 7.4. Bland-Altman analysis showed that the bias was 0.9 events per hour and the limits of agreement were 18.1 and-16.1. The rate of clinical agreement between recordings with PSG AHI30 and patch AHI30 and was 84.7%. The rate of clinical agreement between recordings with PSG AHI< 30 and the patch AHI within (PSG AHI ±10) was 88.7%. The total rate of clinical agreement was 87.4% with 95% confidence interval of 81.4%-91.9%. Conclusions: The new diagnostic patch offers excellent clinical value for detecting sleep apnea across all severity levels as compared with standard in-lab polysomnography. Acknowledgements: funded by NIH grant R44 HL123196-02. Introduction: Sleep bruxism is medical term for repetitive jaw muscle activity, which is characterised by clenching or grinding of the teeth. The frequency of this disorder is reported to be between 8 to 31% in adults. The Abstracts / Sleep Medicine 40 (2017) e186ee363 e221

Association of Social Jetlag With Sleep Quality and Autonomic Cardiac Control During Sleep in Young Healthy Men

Frontiers in Neuroscience, 2019

Social jetlag (SJL), the difference in sleep timing between work and free days is a consequence o... more Social jetlag (SJL), the difference in sleep timing between work and free days is a consequence of the discrepancy between the individual's circadian rhythm and the social clock. SJL is considered a chronic stress factor and has been linked to various health problems. In this field study, we examined for the first time the association between SJL and cardiac regulation during sleep. 33 healthy young men aged 20-26 years participated in the study. The median SJL was used as a cutoff value to assign the participants into two groups with either lower or higher SJL. As a marker of autonomic control we analyzed heart rate variability (HRV) and addressed intra-individual differences between workdays and free days. In subjects with higher SJL, pNN50, an indicator of vagal activity was lower in the first 3 h of sleep on workday as compared to free day (day × sleep block × group, p = 0.015), indicating a more adaptable regulation on free days, when subjects slept according to their own preference. However, in subjects with lower SJL, no HRV differences were found between the two nights. SJL showed correlation with the free day-workday differences of both pNN50 and another vagal index, RMSSD in the first 2 h of sleep (p = 0.023 and 0.047, respectively). In subjects with higher SJL, a different HF power on workdays and free days (p = 0.031) also indicated that a shift in sleep timing is accompanied by an altered parasympathetic activity in the first few hours of sleep. Furthermore, subjective sleep quality on workdays was negatively associated with SJL (p = 0.02), and subjects with higher SJL reported worse sleep quality on workday than on free day (p = 0.027). Taken together, our data call attention on the potential effect of SJL on sleep quality and vagal activity during sleep.

Publisher Correction: Circadian preference towards morningness is associated with lower slow sleep spindle amplitude and intensity in adolescents

Scientific reports, Jan 23, 2018

A correction to this article has been published and is linked from the HTML version of this paper... more

Circadian preference towards morningness is associated with lower slow sleep spindle amplitude and intensity in adolescents

Scientific reports, Jan 6, 2017

Individual circadian preference types and sleep EEG patterns related to spindle characteristics, ... more Individual circadian preference types and sleep EEG patterns related to spindle characteristics, have both been associated with similar cognitive and mental health phenotypes. However, no previous study has examined whether sleep spindles would differ by circadian preference. Here, we explore if spindle amplitude, density, duration or intensity differ by circadian preference and whether these associations are moderated by spindle location, frequency, and time distribution across the night. The participants (N = 170, 59% girls; mean age = 16.9, SD = 0.1 years) filled in the shortened 6-item Horne-Östberg Morningness-Eveningness Questionnaire. We performed an overnight sleep EEG at the homes of the participants. In linear mixed model analyses, we found statistically significant lower spindle amplitude and intensity in the morning as compared to intermediate (P < 0.001) and evening preference groups (P < 0.01; P > 0.06 for spindle duration and density). Spindle frequency moder...

S75 Sleep spindles in humans: From invasive recordings to sexual dimorphism

Clinical Neurophysiology, 2017

S115 Sleep slow wave oscillation and homeostasis

Clinical Neurophysiology, 2017

Moreover, it was recently suggested a link between this hypotheses and the aberrant peripheral ac... more Moreover, it was recently suggested a link between this hypotheses and the aberrant peripheral activity characterized by ectopic evoked and spontaneous nerve activity. Almost all previously cited evidences are the results of non-longitudinal studies, where one or more groups of patients are analysed in a resting situation. Very few information are reported in literature explaining how plastic changes evolve during the use of prosthesis and this is particularly true considering new prototypes of bidirectional neurally hand prosthesis. These implanted neural interfaces for the peripheral nervous system have shown a remarkable potential as tools to restore the bidirectional communication between the hand prosthesis and the nerves in the residuum. In the frame of European founded projects we assessed neuroplastic changes of brain sensorimotor organization (through the assessment of cortical SEPs, MEPs, EEG source analysis, connectivity analysis and fMRI) following the use of a robotic hand during trainings of different durations (4-24 weeks) in four human amputees, providing new advancements in the understanding of the complex phenomena of phantom limb syndrome.

Hullámok nyelvén: a szerotonin és az alvási oszcillációk

Az alvásszabályozásban szerepet játszó központi idegrendszeri struktúrák feltárására irányuló erõ... more Az alvásszabályozásban szerepet játszó központi idegrendszeri struktúrák feltárására irányuló erõfeszítéseik során Michel Jouvet és munkacsoportja felismerték, hogy az agytörzsi magvak nem pusztán és nem elsõsorban anatómiai lokalizáció-juk, hanem különösképpen kémiai jellegzetességeik szerint különülnek el abban a neurofiziológiai rendszerben, amely az alvás-ébrenlét állapotok megjelenését befolyásolja vagy meghatározza (Jouvet, 1969, 1972). A léziós kísérletek mellett ekkor már neurofarmakológiai eljárások bõvítették azt a módszertani repertoárt, ami ter

P370 The thalamo-cortical generators of sleep spindles as revealed by laminar analysis of neocortex

Clinical Neurophysiology, Sep 1, 2017

syndrome, respectively. Long segments (>5 min) of GPi-LFP recordings at rest were selected from e... more syndrome, respectively. Long segments (>5 min) of GPi-LFP recordings at rest were selected from each patient (in PD patients, ''on" and ''off" medication). Results: The two PD patients had low-beta, high-beta and HFO peaks in the ''off" power spectrum. In the ''on" state, the low-beta peak attenuated and the HFO peaks changed in frequency and power, as expected. The patients with dystonia showed theta and high-beta peaks. However, either no HFO peak or a much smaller one (in only two patients) was observed. The two patients with chorea had high-beta and HFO peaks only. The patients with Tourette's síndrome had no evident beta peaks, but HFO activity was very evident. Conclusions: The activity observed in PD patients in the GPi is similar to that observed in the STN, including the presence of HFOs. HFOs are also observed in patients with chorea or Tourette's syndrome, but might be absent or smaller in patients with dystonia. Beta peaks were absent in the two patients with Tourette's syndrome. Significance: The GPi and STN show similar oscillatory activity in PD, including HFOs. Different neurologic diseases are associtated with different oscillatory activities in the GPi.

Az alvás szerkezete és mintázatai autizmus spektrumzavarban

Psychiatria Hungarica : A Magyar Pszichiátriai Társaság tudományos folyóirata, 2008

Human sleep, as an ancient demeanor emerging at the meeting-point of psychogenetic and ontogeneti... more Human sleep, as an ancient demeanor emerging at the meeting-point of psychogenetic and ontogenetic brain development as well as of specific environmental factors, frames the basis of adaptation to complex information processing conditions. Therefore sleep befalls in the focus of modern sleep research as the sensitive indicator of psychological and biological integrity. Autism spectrum disorders (ASD) are characterized by peculiarly altered behaviours occurring in various life situations, which can be traced in the structure and patterns of sleep as well. There is convincing evidence suggesting that ASD are associated with various sleep disorders at times of extreme severity. The frequency of these sleep disorders is different from those seen in typically developing children of the same age and mental abilities, but often overlapping with other neuropsychiatric disorders. The present article while reviewing core methodological milestones of sleep research provides an extensive overview of the nature of sleep disorders emerging in ASD as well as of the composite relationships between psychological and physiological features. Emerging knowledge regarding the etiological background and treatment options will be also addressed.

Dreaming and dream amnesia in the light of reactive and predictive homeostasis

Dreams are often viewed as fascinating but relatively irrelevant mental epihenomena of the sleepi... more Dreams are often viewed as fascinating but relatively irrelevant mental epihenomena of the sleeping mind with questionable or no functional relevance. Despite long hours of oneiric activity, and high individual differences in dream recall, dream amnesia is one of the most robust and universal features of dreaming. In this review, we conceptualize dreaming and dream amnesia as inherent aspects of the homeostatic functions of sleep and wakefulness. In this framework the temporal progression of sleep throughout the night is shaped by reactive and predictive homeostatic functions. Mental activity during sleep conforms to the dynamic interplay of restorative processes and future anticipation, and particularly during the second half of the night, unfolds as a special form of non-constrained, self-referent, and future-oriented cognitive process. Awakening facilitates constrained, goal-directed prospection that competes for shared neural resources with dream production and dream recall, and hence, contributes to dream amnesia. We present the neurophysiological aspects of reactive and predictive homeostasis during sleep, highlighting the putative role of nocturnal cortisol as well as the cortisol awakening response in predictive homeostasis and dream amnesia, respectively. The theoretical and methodological aspect of our proposal is discussed in relation to the study of dream recall, sleep-related cognitive processes and altered dreaming in sleep disorders.

Comparing manual and automatic artifact detection in sleep EEG recordings

bioRxiv (Cold Spring Harbor Laboratory), May 14, 2023

Daily rhythms, demographics and health: findings from a nationally representative survey

bioRxiv (Cold Spring Harbor Laboratory), Apr 9, 2023

Fractal cycles of sleep: a new aperiodic activity-based definition of sleep cycles

bioRxiv (Cold Spring Harbor Laboratory), Jul 4, 2023

Sleep time, social jetlag and intelligence: biology or work timing?

A questionnaire measure of adult attachment anxiety correlates with frontal hemispheric asymmetry in sleep spindle activity

Sleep and Biological Rhythms, Oct 20, 2022

Subjects with high levels of attachment anxiety and neuroticism were proposed to be characterized... more Subjects with high levels of attachment anxiety and neuroticism were proposed to be characterized by higher relative right rather than left frontal activity. Since sleep spindles are argued to reflect enhanced offline neuroplasticity, higher spindle activity measured over the right frontal areas relative to the corresponding left frontal ones could index higher attachment anxiety and neuroticism. Our aim was to explore the relationship between the lateralization patterns of frontally dominant slow sleep spindles and questionnaire measures of adult attachment anxiety and neuroticism. Thirty-four healthy subjects (male = 19; M age = 31.64; SD age = 9.5) were enrolled in our preliminary study. Second night EEG/polysomnography records and questionnaire measures of personality (Zuckerman-Kuhlman Personality Questionnaire) and adult attachment (Relationship Scales Questionnaire) were collected. Frontal slow sleep spindles were measured by the Individual Adjustment Method (IAM), whereas hemispheric asymmetry indexes of spindle occurrence rate, duration, and amplitude were derived as normalized left-right differences (electrode pairs: Fp1-Fp2, F3-F4, and F7-F8). Relative right lateralization of frontolateral and frontopolar slow sleep spindle density and mid-frontal slow spindle duration were associated with attachment anxiety, but spindle lateralization was less closely related to neuroticism. The relationships between frontal slow spindle laterality and attachment anxiety remained statistically significant even after controlling for the effect of neuroticism, whereas attachment avoidance-independence was not correlated with frontal slow spindle lateralization. Right frontal lateralization of slow sleep spindle activity might indicate attachment status in terms of the negative view of the self.

Hullámok nyelvén: a szerotonin és az alvási oszcillációk

A szerotonin és az alvás-ébrenlét állapotok szoros és komplex összefüggése rendkívüli elméleti és... more A szerotonin és az alvás-ébrenlét állapotok szoros és komplex összefüggése rendkívüli elméleti és gyakorlati jelentõségû kérdéskör. A probléma ellentmondásossága és a rendelkezésre álló szakirodalmi adatok fényében sem kellõképpen tisztázott jellege azonban nehezíti az e témakörrel kapcsolatos ismeretek rendszerezését és hasznosítását. A szerotonin alvásszabályozásban játszott szerepének áttekintése során kiemelt figyelmet szentelünk az akut ébresztõ és a hosszabb távon érvényesülõ, cirkadián fázist módosító illetve az alvás homeosztatikus szabályozását moduláló funkciók elkülönült elemzésének. A receptortípusok szerinti differenciált hatások szempontjából az 5-HT1A/7 és 5-HT3 receptorok cirkadián ritmicitást illetve REM alvást szabályozó/ moduláló, valamint az 5-HT2A receptoroknak az alvás homeosztázisában, az alvásintenzitásban, az ultradián alvásorganizációban és az alvás folyamatosságában játszott szerepei kerülnek a tanulmány elemzéseinek fókuszába. Ugyanakkor a szerotonin, a n...

Role of anterior thalamic circuitry during sleep

Epilepsy Research

Prolongation of cortical sleep spindles during hippocampal interictal epileptiform discharges in epilepsy patients

Epilepsia

ObjectiveMemory deficits are frequent among patients with epilepsies affecting the temporal lobe.... more ObjectiveMemory deficits are frequent among patients with epilepsies affecting the temporal lobe. Hippocampal interictal epileptic discharges (hIEDs), the presumed epileptic exaggeration of sharp wave‐ripples (SWRs), are known to contribute to memory dysfunction, but the potential underlying mechanism is unknown. The precise temporal coordination between hippocampal SWRs and corticothalamic spindles during sleep is critical for memory consolidation. Moreover, previous investigation indicated that hIEDs induce neocortical spindlelike oscillation. In the present study, we aimed to assess the influence of hIEDs on neocortical spindles.MethodsWe analyzed the spindle characteristics (duration, amplitude, frequency) of 21 epilepsy patients implanted with foramen ovale (FO) electrodes during a whole night sleep. Scalp sleep spindles were categorized based on their temporal relationship to hIEDs detected on the FO electrodes. Three groups were created: (1) spindles coinciding with hIEDs, (2...

Alvásszabályozás És Hipnotikumok: A Benzodiazepin-Receptor Agonisták Hatásai

As binding sites of the alpha-amino butyric acid receptor complexes benzodiazepine-receptors offe... more As binding sites of the alpha-amino butyric acid receptor complexes benzodiazepine-receptors offer a possibility to enhance hyperpolarization-based inhibition by allosteric modulation. Most of the hypnotic drugs are compounds that bind to benzodiazepine receptors. The effects of these drugs are usually characterized at a descriptive level, without deliberation of the basic processes involved in sleep regulation. This review follows the analysis of hypnotic's effect from a perspective of homeostatic, circadian, ultradian and microstructural regulation of sleep. In contrast to their expected effect benzodiazepines produce a decrease in most of the markers of homeostatic sleep regulation. Ligands with non-benzodiazepine structure (cyclopyrrolones, imidazopyridines, pyrazolopyrimidines) have a permissive or even stimulating effect in some measures of homeostatic sleep regulation. Some benzodiazepines have marked chronobiotic effects, while others interfere with circadian rhythms. Th...

Cortical monitoring of cardiac activity during rapid eye movement sleep: the heartbeat evoked potential in phasic and tonic rapid-eye-movement microstates

Sleep, 2021

Sleep is a fundamental physiological state that facilitates neural recovery during periods of att... more Sleep is a fundamental physiological state that facilitates neural recovery during periods of attenuated sensory processing. On the other hand, mammalian sleep is also characterized by the interplay between periods of increased sleep depth and environmental alertness. Whereas the heterogeneity of microstates during non-rapid-eye-movement (NREM) sleep was extensively studied in the last decades, transient microstates during rapid-eye-movement (REM) sleep received less attention. REM sleep features two distinct microstates: phasic and tonic. Previous studies indicate that sensory processing is largely diminished during phasic REM periods, whereas environmental alertness is partially reinstated when the brain switches into tonic REM sleep. Here, we investigated interoceptive processing as quantified by the heartbeat evoked potential (HEP) during REM microstates. We contrasted the HEPs of phasic and tonic REM periods using two separate databases that included the nighttime polysomnograp...

Morningness is associated with lower sleep spindle amplitudes and intensities during adolescence

Sleep Medicine, 2017

Introduction: Portable home sleep monitors are being increasingly utilized in clinical practice f... more Introduction: Portable home sleep monitors are being increasingly utilized in clinical practice for diagnosing sleep apnea. Most type III home monitors are difficult for patients to set up and wearing the monitors is disruptive to patient's typical sleep pattern. The diagnostic value of an inexpensive easy-to-use lightweight flexible skin-adhesive patch (Som-naPatch) that is non-disruptive to sleep was evaluated in this study. Materials and methods: Simultaneous polysomnography (PSG) and the diagnostic patch recordings were made in 179 subjects (mean age 54.0±13.6 y, 55% male) selected from the databases of patients previously tested with PSG to ensure even representation of the clinically important apnea-hypopnea index (AHI) ranges. The skin-adhesive diagnostic patch weighs less than one ounce and records nasal pressure, blood oxygen saturation, pulse rate, respiratory effort, sleep time and body position. To compare the apnea-hypopnea index of the diagnostic patch with polysomnography, the recordings were auto-scored with the Somnolyzer software (Respironics). Bland-Altman analysis was performed. Sensitivity, specificity and accuracy were calculated and receiver operating characteristic (ROC) curves were constructed for six AHI thresholds (5, 10, 15, 20, 25 and 30 events per hour). The rate of clinical agreement and positive likelihood ratio were calculated. Results: Overnight recordings from 174 subjects were included in the analysis. All six ROC curves had area under the curve of over 0.9. Sensitivity, specificity and accuracy for the optimal threshold of AHI15 were 0.86, 0.83 and 0.85 respectively. Positive likelihood ratio (LRþ) was 7.4. Bland-Altman analysis showed that the bias was 0.9 events per hour and the limits of agreement were 18.1 and-16.1. The rate of clinical agreement between recordings with PSG AHI30 and patch AHI30 and was 84.7%. The rate of clinical agreement between recordings with PSG AHI< 30 and the patch AHI within (PSG AHI ±10) was 88.7%. The total rate of clinical agreement was 87.4% with 95% confidence interval of 81.4%-91.9%. Conclusions: The new diagnostic patch offers excellent clinical value for detecting sleep apnea across all severity levels as compared with standard in-lab polysomnography. Acknowledgements: funded by NIH grant R44 HL123196-02. Introduction: Sleep bruxism is medical term for repetitive jaw muscle activity, which is characterised by clenching or grinding of the teeth. The frequency of this disorder is reported to be between 8 to 31% in adults. The Abstracts / Sleep Medicine 40 (2017) e186ee363 e221

Association of Social Jetlag With Sleep Quality and Autonomic Cardiac Control During Sleep in Young Healthy Men

Frontiers in Neuroscience, 2019

Social jetlag (SJL), the difference in sleep timing between work and free days is a consequence o... more Social jetlag (SJL), the difference in sleep timing between work and free days is a consequence of the discrepancy between the individual's circadian rhythm and the social clock. SJL is considered a chronic stress factor and has been linked to various health problems. In this field study, we examined for the first time the association between SJL and cardiac regulation during sleep. 33 healthy young men aged 20-26 years participated in the study. The median SJL was used as a cutoff value to assign the participants into two groups with either lower or higher SJL. As a marker of autonomic control we analyzed heart rate variability (HRV) and addressed intra-individual differences between workdays and free days. In subjects with higher SJL, pNN50, an indicator of vagal activity was lower in the first 3 h of sleep on workday as compared to free day (day × sleep block × group, p = 0.015), indicating a more adaptable regulation on free days, when subjects slept according to their own preference. However, in subjects with lower SJL, no HRV differences were found between the two nights. SJL showed correlation with the free day-workday differences of both pNN50 and another vagal index, RMSSD in the first 2 h of sleep (p = 0.023 and 0.047, respectively). In subjects with higher SJL, a different HF power on workdays and free days (p = 0.031) also indicated that a shift in sleep timing is accompanied by an altered parasympathetic activity in the first few hours of sleep. Furthermore, subjective sleep quality on workdays was negatively associated with SJL (p = 0.02), and subjects with higher SJL reported worse sleep quality on workday than on free day (p = 0.027). Taken together, our data call attention on the potential effect of SJL on sleep quality and vagal activity during sleep.

Publisher Correction: Circadian preference towards morningness is associated with lower slow sleep spindle amplitude and intensity in adolescents

Scientific reports, Jan 23, 2018

A correction to this article has been published and is linked from the HTML version of this paper... more

Circadian preference towards morningness is associated with lower slow sleep spindle amplitude and intensity in adolescents

Scientific reports, Jan 6, 2017

Individual circadian preference types and sleep EEG patterns related to spindle characteristics, ... more Individual circadian preference types and sleep EEG patterns related to spindle characteristics, have both been associated with similar cognitive and mental health phenotypes. However, no previous study has examined whether sleep spindles would differ by circadian preference. Here, we explore if spindle amplitude, density, duration or intensity differ by circadian preference and whether these associations are moderated by spindle location, frequency, and time distribution across the night. The participants (N = 170, 59% girls; mean age = 16.9, SD = 0.1 years) filled in the shortened 6-item Horne-Östberg Morningness-Eveningness Questionnaire. We performed an overnight sleep EEG at the homes of the participants. In linear mixed model analyses, we found statistically significant lower spindle amplitude and intensity in the morning as compared to intermediate (P < 0.001) and evening preference groups (P < 0.01; P > 0.06 for spindle duration and density). Spindle frequency moder...

S75 Sleep spindles in humans: From invasive recordings to sexual dimorphism

Clinical Neurophysiology, 2017

S115 Sleep slow wave oscillation and homeostasis

Clinical Neurophysiology, 2017

Moreover, it was recently suggested a link between this hypotheses and the aberrant peripheral ac... more Moreover, it was recently suggested a link between this hypotheses and the aberrant peripheral activity characterized by ectopic evoked and spontaneous nerve activity. Almost all previously cited evidences are the results of non-longitudinal studies, where one or more groups of patients are analysed in a resting situation. Very few information are reported in literature explaining how plastic changes evolve during the use of prosthesis and this is particularly true considering new prototypes of bidirectional neurally hand prosthesis. These implanted neural interfaces for the peripheral nervous system have shown a remarkable potential as tools to restore the bidirectional communication between the hand prosthesis and the nerves in the residuum. In the frame of European founded projects we assessed neuroplastic changes of brain sensorimotor organization (through the assessment of cortical SEPs, MEPs, EEG source analysis, connectivity analysis and fMRI) following the use of a robotic hand during trainings of different durations (4-24 weeks) in four human amputees, providing new advancements in the understanding of the complex phenomena of phantom limb syndrome.

Hullámok nyelvén: a szerotonin és az alvási oszcillációk

Az alvásszabályozásban szerepet játszó központi idegrendszeri struktúrák feltárására irányuló erõ... more Az alvásszabályozásban szerepet játszó központi idegrendszeri struktúrák feltárására irányuló erõfeszítéseik során Michel Jouvet és munkacsoportja felismerték, hogy az agytörzsi magvak nem pusztán és nem elsõsorban anatómiai lokalizáció-juk, hanem különösképpen kémiai jellegzetességeik szerint különülnek el abban a neurofiziológiai rendszerben, amely az alvás-ébrenlét állapotok megjelenését befolyásolja vagy meghatározza (Jouvet, 1969, 1972). A léziós kísérletek mellett ekkor már neurofarmakológiai eljárások bõvítették azt a módszertani repertoárt, ami ter