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1.
PLoS Comput Biol ; 15(11): e1007268, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31725712

RESUMO

Origin and functions of intermittent transitions among sleep stages, including short awakenings and arousals, constitute a challenge to the current homeostatic framework for sleep regulation, focusing on factors modulating sleep over large time scales. Here we propose that the complex micro-architecture characterizing the sleep-wake cycle results from an underlying non-equilibrium critical dynamics, bridging collective behaviors across spatio-temporal scales. We investigate θ and δ wave dynamics in control rats and in rats with lesions of sleep-promoting neurons in the parafacial zone. We demonstrate that intermittent bursts in θ and δ rhythms exhibit a complex temporal organization, with long-range power-law correlations and a robust duality of power law (θ-bursts, active phase) and exponential-like (δ-bursts, quiescent phase) duration distributions, typical features of non-equilibrium systems self-organizing at criticality. Crucially, such temporal organization relates to anti-correlated coupling between θ- and δ-bursts, and is independent of the dominant physiologic state and lesions, a solid indication of a basic principle in sleep dynamics.


Assuntos
Fases do Sono/fisiologia , Vigília/fisiologia , Animais , Nível de Alerta/fisiologia , Ritmo Delta/fisiologia , Eletroencefalografia , Homeostase , Masculino , Neurônios , Ratos , Ratos Sprague-Dawley , Sono/fisiologia , Ritmo Teta/fisiologia
2.
Nat Commun ; 10(1): 4770, 2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628317

RESUMO

Animals perform or terminate particular behaviors by integrating external cues and internal states through neural circuits. Identifying neural substrates and their molecular modulators promoting or inhibiting animal behaviors are key steps to understand how neural circuits control behaviors. Here, we identify the Cholecystokinin-like peptide Drosulfakinin (DSK) that functions at single-neuron resolution to suppress male sexual behavior in Drosophila. We found that Dsk neurons physiologically interact with male-specific P1 neurons, part of a command center for male sexual behaviors, and function oppositely to regulate multiple arousal-related behaviors including sex, sleep and spontaneous walking. We further found that the DSK-2 peptide functions through its receptor CCKLR-17D3 to suppress sexual behaviors in flies. Such a neuropeptide circuit largely overlaps with the fruitless-expressing neural circuit that governs most aspects of male sexual behaviors. Thus DSK/CCKLR signaling in the sex circuitry functions antagonistically with P1 neurons to balance arousal levels and modulate sexual behaviors.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Oligopeptídeos/metabolismo , Fatores de Transcrição/metabolismo , Animais , Animais Geneticamente Modificados , Nível de Alerta/fisiologia , Comunicação Celular/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Feminino , Locomoção/fisiologia , Masculino , Proteínas do Tecido Nervoso/genética , Neurônios/citologia , Neuropeptídeos/genética , Oligopeptídeos/genética , Comportamento Sexual Animal/fisiologia , Transdução de Sinais/genética , Sono/fisiologia , Fatores de Transcrição/genética
3.
Artigo em Inglês | MEDLINE | ID: mdl-31540542

RESUMO

Abstract: Recent evidences suggest that non-arousal mechanisms can restore and stabilize breathing in sleeping patients with obstructive sleep apnea. This possibility can be examined under deep sedation which increases the cortical arousal threshold. We examined incidences of cortical arousal at termination of apneas and hypopneas in elderly patients receiving propofol sedation which increases the cortical arousal threshold. Ten elderly patients undergoing advanced endoscopic procedures under propofol-sedation were recruited. Standard polysomnographic measurements were performed to assess nature of breathing, consciousness, and occurrence of arousal at recovery from apneas and hypopneas. A total of 245 periodic apneas and hypopneas were identified during propofol-induced sleep state. Cortical arousal only occurred in 55 apneas and hypopneas (22.5%), and apneas and hypopneas without arousal and desaturation were most commonly observed (65.7%) regardless of the types of disordered breathing. Chi-square test indicated that incidence of no cortical arousal was significantly associated with occurrence of no desaturation. Higher dose of propofol was associated with a higher apnea hypopnea index (r = 0.673, p = 0.033). In conclusion, even under deep propofol sedation, apneas and hypopneas can be terminated without cortical arousal. However, extensive suppression of the arousal threshold can lead to critical hypoxemia suggesting careful respiratory monitoring.


Assuntos
Nível de Alerta/fisiologia , Hidrocortisona/biossíntese , Propofol/farmacologia , Síndromes da Apneia do Sono/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Propofol/administração & dosagem , Estudos Prospectivos , Respiração
4.
Neurology ; 93(13): e1281-e1287, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31484715

RESUMO

OBJECTIVE: To determine whether ascending arousal network (AAn) connectivity is reduced in patients presenting with traumatic coma. METHODS: We performed high-angular-resolution diffusion imaging in 16 patients with acute severe traumatic brain injury who were comatose on admission and in 16 matched controls. We used probabilistic tractography to measure the connectivity probability (CP) of AAn axonal pathways linking the brainstem tegmentum to the hypothalamus, thalamus, and basal forebrain. To assess the spatial specificity of CP differences between patients and controls, we also measured CP within 4 subcortical pathways outside the AAn. RESULTS: Compared to controls, patients showed a reduction in AAn pathways connecting the brainstem tegmentum to a region of interest encompassing the hypothalamus, thalamus, and basal forebrain. When each pathway was examined individually, brainstem-hypothalamus and brainstem-thalamus CPs, but not brainstem-forebrain CP, were significantly reduced in patients. Only 1 subcortical pathway outside the AAn showed reduced CP in patients. CONCLUSIONS: We provide initial evidence for the reduced integrity of axonal pathways linking the brainstem tegmentum to the hypothalamus and thalamus in patients presenting with traumatic coma. Our findings support current conceptual models of coma as being caused by subcortical AAn injury. AAn connectivity mapping provides an opportunity to advance the study of human coma and consciousness.


Assuntos
Nível de Alerta/fisiologia , Lesões Encefálicas/fisiopatologia , Tronco Encefálico/fisiopatologia , Estado de Consciência/fisiologia , Adulto , Prosencéfalo Basal/fisiopatologia , Lesões Encefálicas/complicações , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/fisiopatologia , Feminino , Humanos , Masculino , Vias Neurais/fisiopatologia , Tálamo/fisiologia
5.
Dev Cogn Neurosci ; 39: 100703, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31487608

RESUMO

Preterm birth is a significant risk factor for a range of long-term health problems and developmental disabilities. Though touch plays a central role in many perinatal care strategies, the neurobiological basis of these approaches is seldom considered. C-Tactile afferents (CTs) are a class of unmyelinated nerve fibre activated by low force, dynamic touch. Consistent with an interoceptive function, touch specifically targeted to activate CTs activates posterior insular cortex and has been reported to reduce autonomic arousal. The present study compared the effect of 5 min of CT optimal velocity stroking touch to 5 min of static touch on the heart-rate and oxygen saturation levels of preterm infants between 28- & 37-weeks gestational age. CT touch produced a significant decrease in infants' heart-rates and increase in their blood oxygenation levels, which sustained throughout a 5-min post-touch period. In contrast, there was no significant change in heart-rate or blood oxygenation levels of infants receiving static touch. These findings provide support for the hypothesis that CTs signal the affective quality of nurturing touch, providing a neurobiological substrate for the apparent beneficial effects of neonatal tactile interventions and offering insight for their optimisation.


Assuntos
Nível de Alerta/fisiologia , Recém-Nascido Prematuro/fisiologia , Fibras Nervosas Amielínicas/fisiologia , Neurônios Aferentes/fisiologia , Percepção do Tato/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro/psicologia , Masculino , Distribuição Aleatória , Tato/fisiologia
6.
Nat Commun ; 10(1): 4030, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492881

RESUMO

The ability to track the statistics of our surroundings is a key computational challenge. A prominent theory proposes that the brain monitors for unexpected uncertainty - events which deviate substantially from model predictions, indicating model failure. Norepinephrine is thought to play a key role in this process by serving as an interrupt signal, initiating model-resetting. However, evidence is from paradigms where participants actively monitored stimulus statistics. To determine whether Norepinephrine routinely reports the statistical structure of our surroundings, even when not behaviourally relevant, we used rapid tone-pip sequences that contained salient pattern-changes associated with abrupt structural violations vs. emergence of regular structure. Phasic pupil dilations (PDR) were monitored to assess Norepinephrine. We reveal a remarkable specificity: When not behaviourally relevant, only abrupt structural violations evoke a PDR. The results demonstrate that Norepinephrine tracks unexpected uncertainty on rapid time scales relevant to sensory signals.


Assuntos
Nível de Alerta/fisiologia , Potenciais Evocados Auditivos/fisiologia , Desempenho Psicomotor/fisiologia , Pupila/fisiologia , Tempo de Reação/fisiologia , Som , Estimulação Acústica , Adulto , Encéfalo/metabolismo , Encéfalo/fisiologia , Feminino , Humanos , Masculino , Norepinefrina/metabolismo , Incerteza , Adulto Jovem
7.
Exp Brain Res ; 237(10): 2607-2619, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31372689

RESUMO

The arrangement of musical notes and their time intervals, also known as musical rhythm is one of the core elements of music. Nevertheless, the cognitive process and neural mechanism of the human brain that underlay the perception of musical rhythm are poorly understood. In this study, we hypothesized that changes in musical rhythmic patterns alter the emotional content expressed by music and the way it is perceived, that assumably causes specific changes in the brain functional connectome. Therefore, 18 male children aged 10-14 years old were recruited and exposed to 12 musical excerpts while their brain's electrical activity was recorded using a 32-channel EEG recorder. The musical rhythmic patterns were changed by manipulating only note values in beats while keeping time signature and other elements in a fixed state. The experienced emotions were assessed using a 2-dimensional self-assessment manikin questionnaire. The behavioral data showed that an increase in the complexity of musical rhythmic patterns significantly enhances perceived valence and arousal levels. In addition, the pattern of brain functional connectivity was also estimated using the weighted phase lag index and their association with behavioral changes was calculated. Interestingly, the behavioral changes were mainly associated with alteration of brain functional connectivity at the alpha band in the fronto-central connections. These results emphasize the important role of the motor cortical site-fronto-central connections, in the perception of musical rhythmic pattern. These findings may improve conception of the underlying brain mechanism involved in the perception of musical rhythm.


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Emoções/fisiologia , Música/psicologia , Adolescente , Nível de Alerta/fisiologia , Comportamento/fisiologia , Criança , Humanos , Masculino , Percepção do Tempo
8.
Psychon Bull Rev ; 26(6): 1967-1973, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31385205

RESUMO

Memories are able to update and adapt with new information about the world after they are reactivated. However, it is unknown whether the labile period following reactivation makes episodic memories more amenable to emotion regulation, an application that holds great clinical promise. Here, we investigated the efficacy of cognitive reappraisal to down regulate negative affect in response to reactivated memories. Healthy young adults (N = 119) rated the emotionality of negative pictures. After a partial reactivation of each picture 2 days later, participants voluntarily engaged in a spatial distancing regulation tactic by imagining the reactivated object extremely far away from them. Compared with no-regulation and no-reactivation controls, self-reported arousal for regulated pictures dropped significantly 2 days after the manipulation, despite no significant difference in memory accuracy or valence. These results open up a new line of work that capitalizes on reactivation-based lability to selectively alter enduring arousal responses to emotional memories.


Assuntos
Nível de Alerta/fisiologia , Emoções/fisiologia , Resposta Galvânica da Pele/fisiologia , Memória Episódica , Reconhecimento Visual de Modelos/fisiologia , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
10.
Artigo em Inglês | MEDLINE | ID: mdl-31438489

RESUMO

Children's favourite food and beverage brands use various tactics to foster positive associations and loyalty. This brand-consumer dynamic is frequently influenced by the use of implicit techniques and emotional appeals. Few studies have used physiological methods to examine the connections that brands build with children and the influence this has on their automatic responses. These techniques are potentially less prone to bias than behavioural or cognitive methods. This is the first study to explore the implicit response that children have to images of their favourite food and beverage brands using skin conductance responses as a marker of arousal. Australian children aged 8-11 years (n = 48) were recruited. Images of the participants' favourite branded food and beverage products, alongside images of the same products unpackaged, their family and friends, and neutral objects were presented in a randomised order with a standard timed interval between images. Children were significantly more aroused by branded images of their favourite food and beverage products than by their unpackaged counterparts (p < 0.042, d = 0.4). The physiological response to the branded products was similar to the response to the children's family and friends (p = 0.900, d = -0.02). These findings suggest that children may have an implicit connection to their favourite branded products.


Assuntos
Bebidas , Embalagem de Alimentos , Preferências Alimentares/fisiologia , Alimentos , Fenômenos Fisiológicos da Pele , Nível de Alerta/fisiologia , Austrália , Criança , Feminino , Humanos , Masculino
11.
Appl Ergon ; 81: 102870, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422278

RESUMO

Infrared thermography, thanks to technological developments and lowering prices, is now getting considerable attention as a potential arousal monitor in the safety industry. Nasal skin temperature might be a valid index to track physiological variations due to reduced arousal levels, and its use could prevent a drowsiness-related deterioration of performance. However, the few studies that have investigated nasal skin temperature in applied settings have had inconsistent results. Here, we assessed the validity of nasal skin temperature to monitor changes in arousal levels (from alertness to drowsiness). The participants performed a 2-h simulated driving task while we simultaneously recorded their nasal skin temperature, brain activity (we used frontal delta electroencephalographic [EEG] activity as the reference index of alertness), and driving performance (speeding time). For those variables, we calculated growth curve models. We also collected subjective ratings of alertness and fatigue before and after the driving session. We found that the nasal skin temperature showed a cubic trajectory (it increased for the first 75 min, and then it began to decrease, but such deceleration gradually diminished over time). As expected, frontal delta EEG activity showed an inverted U-shaped quadratic trend (EEG power increased for the first hour and half, and gradually decreased during the last thirty minutes). The speeding time exhibited a similar pattern of change. Subjective sleepiness and fatigue increased after the task. Overall, our results suggest that nasal skin temperature seems to be a valid measure of arousal variations while performing a complex and dynamic everyday task.


Assuntos
Nível de Alerta/fisiologia , Condução de Veículo/psicologia , Fadiga/diagnóstico , Temperatura Cutânea/fisiologia , Termografia/métodos , Adulto , Simulação por Computador , Eletroencefalografia , Feminino , Humanos , Raios Infravermelhos , Masculino , Nariz , Análise e Desempenho de Tarefas , Fatores de Tempo , Adulto Jovem
12.
Sensors (Basel) ; 19(13)2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288378

RESUMO

Existing correlations between features extracted from Electroencephalography (EEG) signals and emotional aspects have motivated the development of a diversity of EEG-based affect detection methods. Both intra-subject and inter-subject approaches have been used in this context. Intra-subject approaches generally suffer from the small sample problem, and require the collection of exhaustive data for each new user before the detection system is usable. On the contrary, inter-subject models do not account for the personality and physiological influence of how the individual is feeling and expressing emotions. In this paper, we analyze both modeling approaches, using three public repositories. The results show that the subject's influence on the EEG signals is substantially higher than that of the emotion and hence it is necessary to account for the subject's influence on the EEG signals. To do this, we propose a data transformation that seamlessly integrates individual traits into an inter-subject approach, improving classification results.


Assuntos
Eletroencefalografia/métodos , Emoções/fisiologia , Modelos Biológicos , Processamento de Sinais Assistido por Computador , Nível de Alerta/fisiologia , Análise de Dados , Bases de Dados Factuais , Humanos , Máquina de Vetores de Suporte
13.
Medicine (Baltimore) ; 98(29): e16483, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31335712

RESUMO

RATIONALE: Electroencephalographic (EEG) changes are frequently observed not only by epileptic seizures but also by metabolic encephalopathies. The EEG changes during hypoglycemia are known as mixed frequency theta to delta activity with higher amplitude than the initial background rhythm. Although there are many reports about hypoglycemia induced EEG changes, few studies of hypoglycemic EEG patterns have been evaluated between arousal and sleep stage. PATIENT CONCERNS: A 45-year-old man who had been diagnosed as type 1 diabetes mellitus for 15 years admitted to the emergency room due to seizure attack. The EEG findings of the patient showed increased amplitude of theta slowing on both hemispheres. The abnormal EEG finding had recovered and the background frequency remarkably increased as the patient fell asleep, but reappeared when he woke up. DIAGNOSIS: The patient was diagnosed as hypoglycemia with altered mentality. INTERVENTIONS: Fifty percent dextrose fluid 50 mL was loaded and maintained with 10% dextrose water afterwards. OUTCOMES: The patient improved after medical treatment. LESSONS: The EEG presentation of hypoglycemia involves low frequency and increased amplitude of delta-theta activity. As the previous studies, we observed medium amplitude semi-rhythmic theta slowing EEG findings on both hemispheres during arousal, indicating hypoglycemia. However, it was stabilized during sleep as background frequency increased and medium amplitude of slowing disappeared. Although there are many reports about hypoglycemia induced EEG changes, few studies of hypoglycemic EEG patterns have been evaluated between arousal and sleep stage. We report a case of different EEG patterns between arousal and sleep stage during hypoglycemia.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Eletroencefalografia , Hipoglicemia/etiologia , Hipoglicemia/fisiopatologia , Convulsões/etiologia , Convulsões/fisiopatologia , Nível de Alerta/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sono/fisiologia
14.
Biol Psychol ; 146: 107737, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31362051

RESUMO

The beloved likely attracts attention. We tested whether the beloved captures early automatic attention, as indicated by an early posterior negativity (EPN) in a typical rapid serial visual presentation (RSVP) task, while replicating previous findings that the beloved receives sustained motivated attention, as indicated by an enhanced late positive potential (LPP) in a standard passive viewing task. Participants viewed beloved, friend, and stranger pictures in RSVP and standard passive viewing tasks. Participants felt most pleasant and aroused while viewing beloved pictures. In the RSVP task, there was a left lateral parietal EPN for the beloved (vs. friend and stranger) between 225 and 300 ms. In the standard passive viewing task, the midline centroparietal LPP between 400 and 1000 ms was larger in response to the beloved than friend and stranger. So, the beloved captures early automatic attention as well as sustained motivated attention, likely because they are evolutionarily significant.


Assuntos
Atenção/fisiologia , Potenciais Evocados/fisiologia , Amor , Adolescente , Adulto , Nível de Alerta/fisiologia , Eletroencefalografia , Feminino , Amigos/psicologia , Humanos , Masculino , Motivação , Estimulação Luminosa , Adulto Jovem
15.
PLoS One ; 14(7): e0219147, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31344045

RESUMO

Skin conductance response (SCR) is used in psychophysiological research to measure the reactions of the autonomic nervous system to reward and punishment. While there is consistent evidence that SCR increases to both aversive and appetitive stimuli, it remains unclear whether SCR simply represents a general index of arousal to motivationally significant outcomes or may also differentiate action or inhibition of action that lead to such outcomes. Furthermore, individual differences in trait sensitivity to reward and punishment can influence physiological arousal during approach and avoidance behaviors. Yet, their inter-relationships have not been examined. To address these gaps, we employed a reward go/no-go task with ⅔ go and ⅓ no-go trials and an individually titrated go response window. Correct go and no-go responses were rewarded while incorrect responses were penalized. We examined whether SCR varied with outcome (win vs. loss), action (go vs. no-go), and individual differences in reward sensitivity (SR) and sex. The results showed greater SCRs to loss vs. win, to go vs. no-go success, and to go success in positive correlation with SR. Further, SCR mediated the relationship between SR and go success rate. In sex differences, men exhibited greater SCR which was more predictive of go success rate relative to women. In contrast, SCR was more predictive of no-go success rate in women. Thus, SCR varies according to behavioral contingency, outcome, sex, and reward sensitivity. These findings add to the literature by characterizing the individual and behavioral factors that may influence physiological arousal in response to salient events.


Assuntos
Resposta Galvânica da Pele/fisiologia , Recompensa , Adulto , Nível de Alerta/fisiologia , Sistema Nervoso Autônomo/fisiologia , Aprendizagem da Esquiva/fisiologia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Motivação/fisiologia , Personalidade/fisiologia , Psicofisiologia , Punição/psicologia , Fatores Sexuais , Análise e Desempenho de Tarefas , Adulto Jovem
16.
Behav Genet ; 49(5): 478-483, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31227945

RESUMO

Tonic immobility (TI) is an effective anti-predator strategy. However, long immobility status on the ground increases the risk of being eaten by predators, and thus insects must rouse themselves when appropriate stimulation is provided. Here, the strength of vibration causing arousal from the state of TI was examined in strains artificially selected for longer duration of TI (L-strains: long sleeper) in a beetle. We provided different strengths of vibration stimuli to the long sleepers in Tribolium castaneum. Although immobilized beetles were never awakened by the stimuli from 0.01 to 0.12 mm in amplitude, almost of the beetles were aroused from immobilized status by the stimulus at 0.21 mm. There was a difference in sensitivity of individuals when the stimuli of 0.14 mm and 0.18 mm were provided. F2 individuals were also bred by crossing experiments of the strains selected for shorter and longer duration of TI. The arousal sensitivity to vibration was well separated in the F2 individuals. A positive relationship was observed between the duration of TI and the vibration amplitude, suggesting that immobilized beetles are difficult to arouse from a deep sleep, while light sleepers are easily aroused by even small vibrations. The results indicate a genetic basis for sensitivity to arousal from TI.


Assuntos
Nível de Alerta/genética , Resposta de Imobilidade Tônica/fisiologia , Tribolium/fisiologia , Animais , Nível de Alerta/fisiologia , Besouros/fisiologia , Feminino , Masculino , Sono/genética , Sono/fisiologia , Vibração
17.
Adv Pharmacol ; 84: 101-119, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31229167

RESUMO

Restless legs syndrome (RLS) is a common sensory-motor circadian disorder, whose basic components include urge to move the legs, unpleasant sensory experience, and periodic leg movements during sleep, all associated with an enhancement of the individual's arousal state. Brain iron deficiency (BID) is considered to be a key initial pathobiological factor, based on alterations of iron acquisition by the brain, also moderated by genetic factors. In addition to the well-known dopaminergic involvement in RLS, previous studies pointed out that BID brings also a hyperglutamatergic state that influences a dysfunctional cortico-striatal-thalamic-cortical circuit in genetically vulnerable individuals. However, the enhancement of arousal mechanisms in RLS may also be explained by functional changes of the ascending arousal systems and by deficitary GABA-mediated inhibitory control. Very recently, it was also suggested that BID induces a hypoadenosinergic state in RLS, thus possibly providing a link for a putative unified pathophysiological mechanism accounting for both hyperarousal and sensory-motor signs. Consequently, RLS might be viewed as a multitransmitter neurochemical disorder, globally resulting in enhanced excitability and decreased inhibition. In this framework, understanding the complex interaction of different neuronal circuits in generating the symptoms of RLS is mandatory both for a better diagnostic refinement and for an innovative therapeutic support. Notably, multiple neurotransmission dysfunction, either primary or triggered by BID, may also bridge the gap between RLS and other chronic pain disorders. This chapter summarizes the current experimental and clinical findings into a heuristic model of the electrophysiology and neurochemistry underlying RLS.


Assuntos
Nível de Alerta/fisiologia , Encéfalo/fisiopatologia , Ácido Glutâmico/metabolismo , Síndrome das Pernas Inquietas/fisiopatologia , Ácido gama-Aminobutírico/metabolismo , Dopamina/metabolismo , Humanos
18.
Neuron ; 103(4): 686-701.e8, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31248729

RESUMO

The role of serotonin (5-HT) in sleep is controversial: early studies suggested a sleep-promoting role, but eventually the paradigm shifted toward a wake-promoting function for the serotonergic raphe. Here, we provide evidence from zebrafish and mice that the raphe are critical for the initiation and maintenance of sleep. In zebrafish, genetic ablation of 5-HT production by the raphe reduces sleep, sleep depth, and the homeostatic response to sleep deprivation. Pharmacological inhibition or ablation of the raphe reduces sleep, while optogenetic stimulation increases sleep. Similarly, in mice, ablation of the raphe increases wakefulness and impairs the homeostatic response to sleep deprivation, whereas tonic optogenetic stimulation at a rate similar to baseline activity induces sleep. Interestingly, burst optogenetic stimulation induces wakefulness in accordance with previously described burst activity of the raphe during arousing stimuli. These results indicate that the serotonergic system promotes sleep in both diurnal zebrafish and nocturnal rodents. VIDEO ABSTRACT.


Assuntos
Camundongos/fisiologia , Núcleos da Rafe/fisiologia , Serotonina/fisiologia , Sono/fisiologia , Peixe-Zebra/fisiologia , Animais , Nível de Alerta/genética , Nível de Alerta/fisiologia , Buspirona/farmacologia , Ritmo Circadiano/fisiologia , Fenclonina/farmacologia , Homeostase , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Optogenética , Quipazina/farmacologia , Neurônios Serotoninérgicos/efeitos dos fármacos , Neurônios Serotoninérgicos/fisiologia , Serotonina/biossíntese , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Privação do Sono/genética , Privação do Sono/fisiopatologia , Triptofano Hidroxilase/deficiência , Triptofano Hidroxilase/genética , Vigília/genética , Vigília/fisiologia , Proteínas de Peixe-Zebra/deficiência , Proteínas de Peixe-Zebra/genética
19.
Nat Hum Behav ; 3(6): 636-645, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31190022

RESUMO

Effective decision-making requires integrating evidence over time. For simple perceptual decisions, previous work suggests that humans and animals can integrate evidence over time, but not optimally. This suboptimality could arise from sources including neuronal noise, weighting evidence unequally over time (that is, the 'integration kernel'), previous trial effects and an overall bias. Here, using an auditory evidence accumulation task in humans, we report that people exhibit all four suboptimalities, some of which covary across the population. Pupillometry shows that only noise and the integration kernel are related to the change in pupil response. Moreover, these two different suboptimalities were related to different aspects of the pupil signal, with the individual differences in pupil response associated with individual differences in the integration kernel, while trial-by-trial fluctuations in pupil response were associated with trial-by-trial fluctuations in noise. These results suggest that different suboptimalities relate to distinct pupil-linked processes, possibly related to tonic and phasic norepinephrine activity.


Assuntos
Nível de Alerta/fisiologia , Tomada de Decisões/fisiologia , Individualidade , Percepção/fisiologia , Desempenho Psicomotor/fisiologia , Pupila/fisiologia , Adulto , Percepção Auditiva/fisiologia , Medições dos Movimentos Oculares , Humanos , Adulto Jovem
20.
Depress Anxiety ; 36(7): 635-646, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31209965

RESUMO

BACKGROUND: Interpersonal touch is a key aspect of human interaction and a usually very comforting experience. For patients suffering from posttraumatic stress disorders (PTSD) caused by interpersonal traumatization, such touch is affectively ambiguous. METHODS: In two studies, we investigated the experience and neural processing of various types of interpersonal and impersonal touch in patients as compared with healthy controls. RESULTS: Patients strongly disliked show, interpersonal skin-to-skin stroking, while controls appreciated this kind of touch. No group differences were observed for ratings of impersonal touch. Similarly, the neural activation differed between groups for interpersonal, but not for impersonal touch. The interpersonal touch aversion in patients was accompanied by enhanced blood-oxygen-level-dependent response in the superior temporal gyrus and by a pronounced reduction of response in the hippocampus. This reduction was significantly correlated to symptoms of negative alterations and arousal within the patients. CONCLUSION: We interpret the hippocampal suppression as an attempt to control traumatic memories, evoked by interpersonal touch. This mechanism may maintain the aversion of interpersonal touch in patients with interpersonal trauma-related PTSD.


Assuntos
Relações Interpessoais , Trauma Psicológico/fisiopatologia , Trauma Psicológico/psicologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Tato , Adulto , Nível de Alerta/fisiologia , Feminino , Hipocampo/fisiopatologia , Humanos , Memória/fisiologia , Pessoa de Meia-Idade , Adulto Jovem
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