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1.
Medicine (Baltimore) ; 99(17): e19968, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32332682

RESUMO

INTRODUCTION: Hyperekplexia is a rare hereditary neurological disorder; only 5 glycine receptor alpha 1 subunit gene (GLRA1) mutations have been reported in 5 Chinese patients. We report a Chinese infant with hyperekplexia and a novel mutation at c.292G > A. PATIENT CONCERNS: A Chinese infant with hyperekplexia and a novel mutation at c.292G > A. DIAGNOSIS: All exons of GLRA1 were sequenced in her parents and her, which revealed a mutation at c.1030C > T and another novel mutation at c.292G > A. Her diagnosis was confirmed as hereditary hyperekplexia with GlRA1 hybrid gene mutations based on the sequencing results. INTERVENTIONS: She was treated with clonazepam. OUTCOMES: Her muscle hypertonia recovered rapidly and the excessive startle reflex to unexpected stimuli was significantly reduced. CONCLUSION: Genetic DNA sequencing is a crucial method for diagnosing hyperekplexia-related gene mutation.


Assuntos
Receptores da Glicina/genética , Rigidez Muscular Espasmódica/genética , China , Clonazepam/uso terapêutico , Feminino , Humanos , Lactente , Mutação/genética , Reflexo de Sobressalto/efeitos dos fármacos , Rigidez Muscular Espasmódica/tratamento farmacológico
2.
Nat Commun ; 11(1): 1170, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127541

RESUMO

Asymmetries in motor behavior, such as human hand preference, are observed throughout bilateria. However, neural substrates and developmental signaling pathways that impose underlying functional lateralization on a broadly symmetric nervous system are unknown. Here we report that in the absence of over-riding visual information, zebrafish larvae show intrinsic lateralized motor behavior that is mediated by a cluster of 60 posterior tuberculum (PT) neurons in the forebrain. PT neurons impose motor bias via a projection through the habenular commissure. Acquisition of left/right identity is disrupted by heterozygous mutations in mosaic eyes and mindbomb, genes that regulate Notch signaling. These results define the neuronal substrate for motor asymmetry in a vertebrate and support the idea that haploinsufficiency for genes in a core developmental pathway destabilizes left/right identity.


Assuntos
Atividade Motora/fisiologia , Neurônios/fisiologia , Peixe-Zebra/fisiologia , Animais , Animais Geneticamente Modificados , Diencéfalo/fisiologia , Proteínas do Olho/genética , Habenula/fisiologia , Larva/fisiologia , Mutação , Fototaxia , Receptores Notch/metabolismo , Reflexo de Sobressalto , Ubiquitina-Proteína Ligases/genética , Proteínas de Peixe-Zebra/genética
3.
PLoS Comput Biol ; 16(2): e1007065, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32012146

RESUMO

The limited capacity of recent memory inevitably leads to partial memory of past stimuli. There is also evidence that behavioral and neural responses to novel or rare stimuli are dependent on one's memory of past stimuli. Thus, these responses may serve as a probe of different individuals' remembering and forgetting characteristics. Here, we utilize two lossy compression models of stimulus sequences that inherently involve forgetting, which in addition to being a necessity under many conditions, also has theoretical and behavioral advantages. One model is based on a simple stimulus counter and the other on the Information Bottleneck (IB) framework which suggests a more general, theoretically justifiable principle for biological and cognitive phenomena. These models are applied to analyze a novelty-detection event-related potential commonly known as the P300. The trial-by-trial variations of the P300 response, recorded in an auditory oddball paradigm, were subjected to each model to extract two stimulus-compression parameters for each subject: memory length and representation accuracy. These parameters were then utilized to estimate the subjects' recent memory capacity limit under the task conditions. The results, along with recently published findings on single neurons and the IB model, underscore how a lossy compression framework can be utilized to account for trial-by-trial variability of neural responses at different spatial scales and in different individuals, while at the same time providing estimates of individual memory characteristics at different levels of representation using a theoretically-based parsimonious model.


Assuntos
Memória/fisiologia , Reflexo de Sobressalto , Estimulação Acústica/métodos , Adulto , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino
4.
J Pharm Pharmacol ; 72(1): 149-160, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31713882

RESUMO

OBJECTIVES: A botanical drug derived from the ethanolic extract composed of Clematis chinensis Osbeck (Ranunculaceae), Trichosanthes kirilowii Maximowicz (Cucurbitaceae) and Prunella vulgaris Linné (Lamiaceae) has been used to ameliorate rheumatoid arthritis as an ethical drug in Korea. In our study, we investigated the effect of this herbal complex extract (HCE) on schizophrenia-like behaviours induced by MK-801. METHODS: HCE (30, 100 or 300 mg/kg, p.o) was orally administered to male ICR mice to a schizophrenia-like animal model induced by MK-801. We conducted an acoustic startle response task, an open-field task, a novel object recognition task and a social novelty preference task. KEY FINDINGS: We found that a single administration of HCE (100 or 300 mg/kg) ameliorated MK-801-induced abnormal behaviours including sensorimotor gating deficits and social or object recognition memory deficits. In addition, MK-801-induced increases in phosphorylated Akt and GSK-3ß expression levels in the prefrontal cortex were reversed by HCE (30, 100 or 300 mg/kg). CONCLUSIONS: These results imply that HCE ameliorates MK-801-induced dysfunctions in prepulse inhibition, social interactions and cognitive function, partly by regulating the Akt and GSK-3ß signalling pathways.


Assuntos
Antipsicóticos/farmacologia , Comportamento Animal/efeitos dos fármacos , Cognição/efeitos dos fármacos , Disfunção Cognitiva/prevenção & controle , Transtornos Neurológicos da Marcha/prevenção & controle , Extratos Vegetais/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Esquizofrenia/prevenção & controle , Filtro Sensorial/efeitos dos fármacos , Animais , Clematis , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Modelos Animais de Doenças , Maleato de Dizocilpina , Transtornos Neurológicos da Marcha/induzido quimicamente , Transtornos Neurológicos da Marcha/fisiopatologia , Transtornos Neurológicos da Marcha/psicologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Camundongos Endogâmicos ICR , Fosforilação , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Prunella , Reconhecimento Psicológico/efeitos dos fármacos , Reflexo de Sobressalto/efeitos dos fármacos , Esquizofrenia/induzido quimicamente , Psicologia do Esquizofrênico , Comportamento Social , Trichosanthes
5.
J Clin Neurophysiol ; 36(6): 452-459, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31688329

RESUMO

It has been well documented that a prepared response can be triggered at short latency following the presentation of a loud acoustic stimulus that evokes a reflexive startle response. Different hypotheses have been proposed for this so-called "StartReact" effect, although there is still much debate surrounding the physiological mechanisms involved in the observed reduction in reaction time (RT). In this review, we outline the various neurophysiological explanations underlying the StartReact effect and summarize the data supporting, and at times opposing, each possibility. Collectively, the experimental results do not unequivocally support a single explanation and we suggest the most parsimonious mechanism may involve a hybrid framework involving a distribution of neural pathways. Specifically, we propose that multiple node networks at the cortical, brainstem, and spinal levels are involved in response preparation and initiation, and the relative contributions of these structures depends on the type of stimulus delivered and the type of movement required. This approach may lead to greater understanding of the pathways involved in response preparation, initiation, and execution for both healthy and motor disordered populations.


Assuntos
Tempo de Reação/fisiologia , Reflexo de Sobressalto/fisiologia , Estimulação Acústica/métodos , Feminino , Humanos , Masculino , Movimento/fisiologia
6.
Bull Exp Biol Med ; 168(2): 300-303, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31776950

RESUMO

Phenotypical study was carried out in rats with pendulum movements. The animals exhibited a high level of abortive seizures in response to audiogenic stimuli and longer postictal catalepsy in comparison with those in Wistar population. Seizure severity positively correlated with the duration of poststimulus catalepsy (r=0.90). High aggressiveness towards humans, the absence of BP elevation in stress, lower body weights, and lower weights of the kidneys and spleen in PM rats are considered concomitant traits. Correlations were detected between startle-1 and BP in rats with pendulum movements (r=0.70) and between startle-10 and BP in narcotized Wistar rats (r=-0.0.71). The newly described signs in rats with pendulum movements did not contradict the signs of the focal seizure model with typical automatisms in humans.


Assuntos
Automatismo/fisiopatologia , Reflexo de Sobressalto/fisiologia , Convulsões/patologia , Estimulação Acústica , Animais , Pressão Sanguínea/fisiologia , Catalepsia/fisiopatologia , Rim/fisiopatologia , Movimento/fisiologia , Ratos , Ratos Wistar , Baço/fisiopatologia
7.
J Neuroinflammation ; 16(1): 194, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31660990

RESUMO

BACKGROUND: Hypoxic-ischemic (HI) encephalopathy causes life-long morbidity and premature mortality in term neonates. Therapies in addition to whole-body cooling are under development to treat the neonate at risk for HI encephalopathy, but are not a quickly measured serum inflammatory or neuronal biomarkers to rapidly and accurately identify brain injury in order to follow the efficacy of therapies. METHODS: In order to identify potential biomarkers for early inflammatory and neurodegenerative events after neonatal hypoxia-ischemia, both male and female Wistar rat pups at postnatal day 7 (P7) were used and had their right carotid artery permanently doubly occluded and exposed to 8% oxygen for 90 min. Sensory and cognitive parameters were assessed by open field, rotarod, CatWalk, and Morris water maze (MWM) test. Plasma and CSF biomarkers were investigated on the acute (24 h and 72 h) and chronic phase (4 weeks). Brains were assessed for gene expression analysis by quantitative RT-PCR Array. RESULTS: We found a delay of neurological reflex maturation in HI rats. We observed anxiolytic-like baseline behavior in males more than females following HI injury. HI rats held on the rotarod for a shorter time comparing to sham. HI injury impaired spatial learning ability on MWM test. The CatWalk assessment demonstrated a long-term deficit in gait parameters related to the hind paw. Proinflammatory biomarkers such as IL-6 in plasma and CCL2 and TNF-α in CSF showed an upregulation at 24 h after HI while other cytokines, such as IL-17A and CCL5, were upregulated after 72 h in CSF. At 24 h post-injury, we observed an increase of Edn1, Hif1-α, and Mmp9 mRNA levels in the ipsilateral vs the contralateral hemisphere of HI rats. An upregulation of genes involved with clotting and hematopoietic processes was observed 72 h post-injury. CONCLUSIONS: Our work showed that, in the immature brain, the HI injury induced an early increased production of several proinflammatory mediators detectable in plasma and CSF, followed by tissue damage in the hypoxic hemisphere and short-term as well as long-lasting neurobehavioral deficits.


Assuntos
Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Mediadores da Inflamação/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Animais , Animais Recém-Nascidos , Biomarcadores/metabolismo , Feminino , Masculino , Aprendizagem em Labirinto/fisiologia , Distribuição Aleatória , Ratos , Ratos Wistar , Reflexo de Sobressalto/fisiologia , Fatores de Tempo
8.
Biol Psychol ; 148: 107771, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31526826

RESUMO

This study examined the associations between Reinforcement Sensitivity Theory (RST-PQ, Corr & Cooper, 2016) and psychopathy traits (LSRPS, Levenson et al., 1995) in university students. The aim was to identify psychopathy and RST traits associated with prepulse inhibition (PPI) of acoustic startle and ERP responses by using two prepulse-stimulus intensities (70 and 85 dB) combined with a 105 dB startle pulse (200 ms prepulse-plus-pulse interval). The higher intensity prepulse produced a larger PPI, although both prepulse stimuli reliably activated the startle system. Higher Primary Psychopathy was associated with a higher Defensive-Fight trait and both measures were associated with larger PPI. A principal components factor analysis disclosed an N1-startle factor that was a significant predictor of both reward reactivity and Goal-Drive Persistence scores. Results appear in line with Newman's response modulation hypothesis emphasizing the engagement of attention and recognition of stimulus salience, which may be disrupted in psychopathy.


Assuntos
Potenciais Evocados/fisiologia , Personalidade/fisiologia , Inibição Pré-Pulso/fisiologia , Teoria Psicológica , Reforço Psicológico , Estimulação Acústica/métodos , Adulto , Atenção , Feminino , Objetivos , Humanos , Masculino , Análise de Componente Principal , Reflexo de Sobressalto/fisiologia , Recompensa , Estudantes/psicologia , Adulto Jovem
9.
Proc Natl Acad Sci U S A ; 116(41): 20556-20561, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31548427

RESUMO

The need to make fast decisions under risky and uncertain conditions is a widespread problem in the natural world. While there has been extensive work on how individual organisms dynamically modify their behavior to respond appropriately to changing environmental conditions (and how this is encoded in the brain), we know remarkably little about the corresponding aspects of collective information processing in animal groups. For example, many groups appear to show increased "sensitivity" in the presence of perceived threat, as evidenced by the increased frequency and magnitude of repeated cascading waves of behavioral change often observed in fish schools and bird flocks under such circumstances. How such context-dependent changes in collective sensitivity are mediated, however, is unknown. Here we address this question using schooling fish as a model system, focusing on 2 nonexclusive hypotheses: 1) that changes in collective responsiveness result from changes in how individuals respond to social cues (i.e., changes to the properties of the "nodes" in the social network), and 2) that they result from changes made to the structural connectivity of the network itself (i.e., the computation is encoded in the "edges" of the network). We find that despite the fact that perceived risk increases the probability for individuals to initiate an alarm, the context-dependent change in collective sensitivity predominantly results not from changes in how individuals respond to social cues, but instead from how individuals modify the spatial structure, and correspondingly the topology of the network of interactions, within the group. Risk is thus encoded as a collective property, emphasizing that in group-living species individual fitness can depend strongly on coupling between scales of behavioral organization.


Assuntos
Comunicação Animal , Comportamento Animal/fisiologia , Peixes/fisiologia , Processos Grupais , Dinâmica Populacional , Reflexo de Sobressalto/fisiologia , Comportamento Social , Animais , Tomada de Decisões , Modelos Biológicos
10.
PLoS One ; 14(9): e0222805, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31550290

RESUMO

The role of state anxiety and state fear in placebo effects is still to be determined. We aimed to investigate the effect of fear of movement-related pain (FMRP) and contextual pain related anxiety (CPRA) on the magnitude of placebo analgesia induced by verbal suggestion. Fifty-six female participants completed a modified voluntary joystick movement paradigm (VJMP) where half participated in a predictable pain condition (PC), in which one of the joystick movements is always followed by pain and the other movement is never followed by pain, and half in an unpredictable pain condition (UC), in which pain was delivered unpredictably. By varying the level of pain predictability, FMRP and CPRA were induced in PC and UC respectively. Colour stimuli were presented at the beginning of each trail. Half of the participants were verbally informed that the green or red colour indicated less painful stimuli (experimental groups), the other half did not receive any suggestion (control groups). We measured self-reported pain intensity, expectancy of pain intensity (PC only), pain related fear and anxiety (eyeblink startle response and self-ratings) and avoidance behaviour (movement-onset latency and duration). The results indicate that the placebo effect was successfully induced in both experimental conditions. In the PC, the placebo effect was predicted by expectancy. Despite the fact that FMRP and CPRA were successfully induced, no difference was found in the magnitude of the placebo effect between PC and UC. Concluding, we did not find a divergent effect of fear and anxiety on placebo analgesia.


Assuntos
Analgesia/métodos , Ansiedade/psicologia , Medo/psicologia , Dor/psicologia , Comportamento Verbal/fisiologia , Adulto , Ansiedade/etiologia , Aprendizagem da Esquiva/fisiologia , Condicionamento Psicológico/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Movimento/fisiologia , Dor/etiologia , Medição da Dor/estatística & dados numéricos , Efeito Placebo , Reflexo de Sobressalto/fisiologia , Autorrelato/estatística & dados numéricos , Adulto Jovem
11.
Nat Commun ; 10(1): 3831, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444339

RESUMO

When injured, fish release an alarm substance (Schreckstoff) that elicits fear in members of their shoal. Although Schreckstoff has been proposed to be produced by club cells in the skin, several observations indicate that these giant cells function primarily in immunity. Previous data indicate that the alarm substance can be isolated from mucus. Here we show that mucus, as well as bacteria, are transported from the external surface into club cells, by cytoplasmic transfer or invasion of cells, including neutrophils. The presence of bacteria inside club cells raises the possibility that the alarm substance may contain a bacterial component. Indeed, lysate from a zebrafish Staphylococcus isolate is sufficient to elicit alarm behaviour, acting in concert with a substance from fish. These results suggest that Schreckstoff, which allows one individual to unwittingly change the emotional state of the surrounding population, derives from two kingdoms and is associated with processes that protect the host from bacteria.


Assuntos
Comunicação Animal , Pele/metabolismo , Staphylococcus/metabolismo , Peixe-Zebra/fisiologia , Animais , Animais Geneticamente Modificados , Medo/fisiologia , Células Gigantes/metabolismo , Células Gigantes/microbiologia , Microscopia Intravital , Muco/citologia , Muco/metabolismo , Muco/microbiologia , Neutrófilos/metabolismo , Neutrófilos/microbiologia , Imagem Óptica , Reflexo de Sobressalto/fisiologia , Pele/citologia , Pele/microbiologia , Simbiose/fisiologia , Peixe-Zebra/lesões , Peixe-Zebra/microbiologia
12.
Horm Behav ; 115: 104564, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31421075

RESUMO

Traumatized women are more likely than traumatized men to develop post-traumatic stress disorder (PTSD). Still, the inclusion of females in animal models of PTSD has largely been avoided, likely due to the variable hormone profile of female rodents. Because a valid animal model of PTSD that incorporates females is still needed, we examined the influence of estrous stage and ovarian hormones on the female rat response to a predator-based psychosocial stress model of PTSD. Female Sprague-Dawley rats were exposed to psychosocial stress or control conditions for 31 days. Stressed rats were given two cat exposures and daily social instability; control rats were handled daily. Beginning on Day 32, rats underwent physiological or behavioral testing. In Experiment 1, vaginal smears were collected on days of the first and second cat exposures and each day of behavioral testing to determine estrous stage. In Experiments 2 and 3, ovariectomized or sham control rats were exposed to stress or control conditions. Then, they were given behavioral testing (Exp 2), or their hearts were isolated and subjected to ischemia/reperfusion on a Langendorff isolated heart system (Exp 3). Chronic stress increased anxiety-like behavior, irrespective of estrous stage or ovariectomy condition. Ovariectomized females displayed greater startle responses and anxiety-like behavior than sham rats. Stress had no impact on myocardial sensitivity to ischemic injury; however, ovariectomized females exhibited greater ischemia-induced infarction than sham rats. These findings suggest that ovarian hormones may prevent anxiety-like behavior and be cardioprotective in non-stressed controls, but they do not interact with chronic stress to influence the development of PTSD-like sequelae in female rats.


Assuntos
Ansiedade , Comportamento Animal/fisiologia , Ciclo Estral/fisiologia , Ovariectomia , Reflexo de Sobressalto , Transtornos de Estresse Pós-Traumáticos , Estresse Psicológico , Animais , Ansiedade/etiologia , Ansiedade/metabolismo , Ansiedade/fisiopatologia , Modelos Animais de Doenças , Ciclo Estral/metabolismo , Feminino , Ratos , Ratos Sprague-Dawley , Reflexo de Sobressalto/fisiologia , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Estresse Psicológico/complicações , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia
13.
Int J Psychophysiol ; 144: 40-46, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31415796

RESUMO

Individuals with eating disorders have exhibited both positive and negative emotional responses to food when assessed via self-report and psychophysiology. These mixed findings may be explained by a lack of association between self-report and physiological measures, and the degree of association may differ based on core eating disorder symptoms like dietary restriction and binge eating. Women from the community (N = 82) were recruited based on the presence or absence of dietary restriction and binge eating. We examined the startle eyeblink reflex, a physiological measure of defensive motivation, in relation to self-reported valence, arousal, and craving ratings of emotional (positive, neutral, negative) and food (high- and low-calorie) images. Dietary restriction and binge eating were investigated as moderators of self-report/physiology relationships. Replicating extant literature, valence ratings of emotional images were correlated with startle blink reflex magnitude, with more unpleasant ratings related to higher startle eyeblink reflex magnitudes. Increased craving, but not valence, ratings of food images were related to lower startle blink reflex magnitudes. Dietary restriction and binge eating did not moderate the relationship between self-report ratings and startle blink magnitude to food. Our findings suggest that self-reported appetitive motivation towards food relates to a decrease in physiologically measured aversion towards food. Future research should examine the extent to which self-report ratings correlate with physiological indices of positive emotion (e.g., postauricular reflex, zygomaticus major) during the viewing of food images in both patients with eating disorders and healthy controls.


Assuntos
Piscadela/fisiologia , Fissura/fisiologia , Sinais (Psicologia) , Emoções/fisiologia , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Alimentos , Reflexo de Sobressalto/fisiologia , Adolescente , Adulto , Idoso , Bulimia/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade , Autorrelato , Adulto Jovem
14.
Biol Bull ; 237(1): 48-62, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31441698

RESUMO

Anthropogenic activities and climate change have resulted in an increase of hypoxic conditions in nearshore ecosystems worldwide. Depending on the persistence of a hypoxic event, the survival of aquatic animals can be compromised. Temperate fish exposed to hypoxia display a reduction in the probability of eliciting startle responses thought to be important for escape from predation. Here we examine the effect of hypoxia on the probability of eliciting fast-startle responses (fast-starts) of a tropical fish, the white grunt (Haemulon plumieri), and whether hypoxia has a prolonged impact on behavior once the fish are returned to normoxic conditions. White grunts collected from the San Juan Bay Estuary in Puerto Rico were exposed to an oxygen concentration of 2.5 mg L-1 (40% dissolved oxygen). We found a significant reduction in auditory-evoked fast-starts that lasted for at least 24 hours after fish were returned to normoxic conditions. Accessibility to the neuronal networks that underlie startle responses was an important motivator for this study. Mauthner cells are identifiable neurons found in most fish and amphibians, and these cells are known to initiate fast-starts in teleost fishes. The assumption that most of the short-latency responses in this study are Mauthner cell initiated provided the impetus to characterize the white grunt Mauthner cell. The identification of the cell provides a first step in understanding how low oxygen levels may impact a single cell and its circuit and the behavior it initiates.


Assuntos
Comportamento Animal/fisiologia , Hipóxia/fisiopatologia , Perciformes/fisiologia , Reflexo de Sobressalto/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Oxigênio/farmacologia , Reflexo de Sobressalto/efeitos dos fármacos , Clima Tropical
15.
Ann Clin Transl Neurol ; 6(9): 1900-1904, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31392847

RESUMO

We report sleep phenotypes and polysomnographic findings in two siblings with a novel homozygous variant of the GLRA1 gene causing hereditary hyperekplexia (HH). Both sisters had startles during wakefulness and sleep, sleep terrors, and one had symptoms of REM sleep behavior disorder (RBD). Frequent startles were found in NREM sleep associated with NREM parasomnias in deep sleep. In REM sleep, both had motor behaviors and increased phasic/tonic muscle activities confirming RBD. Clonazepam improved startles, motor behaviors, and muscle activities in REM sleep. Impaired glycinergic transmission in human HH could be involved in the pathophysiology of RBD and NREM parasomnias.


Assuntos
Hiperecplexia/fisiopatologia , Parassonias/fisiopatologia , Transtorno do Comportamento do Sono REM/fisiopatologia , Receptores da Glicina/genética , Sono/genética , Adolescente , Adulto , Feminino , Humanos , Hiperecplexia/complicações , Hiperecplexia/genética , Parassonias/complicações , Parassonias/genética , Polissonografia , Transtorno do Comportamento do Sono REM/complicações , Transtorno do Comportamento do Sono REM/genética , Reflexo de Sobressalto/genética , Irmãos
16.
Exp Brain Res ; 237(9): 2353-2365, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31292693

RESUMO

The timing and magnitude of muscle responses to perturbations are critical for acting in uncertain environments. A planned movement can strongly influence average muscle responses to perturbations, but certainty in when a perturbation will arrive changes this effect. The objective of this study was to investigate how uncertainty in perturbation timing influences the preparation and release of involuntary, perturbation-triggered responses. We hypothesized that uncertainty would influence the average magnitude of triggered responses and how they develop in time. We investigated three levels of uncertainty in when a proprioceptive cue to move would arrive by changing the duration and variability of the time between a preparation and movement cue. Participants performed ballistic elbow extension movements in response to the movement cue. Unexpected, large perturbations that flexed the elbow were delivered at various times between the preparation and movement cues to evaluate how cue uncertainty influenced the development of triggered responses. We found that this uncertainty strongly influences how a motor response is prepared, and the efficacy of triggering that response by a postural perturbation. When timing was certain, the motor plan was prepared within 150 ms of the expected disturbance, and consistently released earlier by a perturbation than could be done voluntarily. Less predictable stimuli led to much earlier planning and a lower probability of releasing the plan early. These results clarify how uncertainty in when to move influences the planning and early release of perturbation-triggered responses, demonstrating an effect similar to previous reports on the planning of volitional movements.


Assuntos
Atividade Motora/fisiologia , Músculo Esquelético/fisiologia , Propriocepção/fisiologia , Reflexo de Sobressalto/fisiologia , Reflexo de Estiramento/fisiologia , Adulto , Sinais (Psicologia) , Eletromiografia , Retroalimentação Sensorial/fisiologia , Feminino , Humanos , Masculino , Fatores de Tempo , Incerteza , Adulto Jovem
17.
PLoS Comput Biol ; 15(7): e1006927, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31356593

RESUMO

The brain constantly generates predictions about the environment to guide action. Unexpected events lead to surprise and can necessitate the modification of ongoing behavior. Surprise can occur for any sensory domain, but it is not clear how these separate surprise signals are integrated to affect motor output. By applying a trial-to-trial Bayesian surprise model to human electroencephalography data recorded during a cross-modal oddball task, we tested whether there are separate predictive models for different sensory modalities (visual, auditory), or whether expectations are integrated across modalities such that surprise in one modality decreases surprise for a subsequent unexpected event in the other modality. We found that while surprise was represented in a common frontal signature across sensory modalities (the fronto-central P3 event-related potential), the single-trial amplitudes of this signature more closely conformed to a model with separate surprise terms for each sensory domain. We then investigated whether surprise-related fronto-central P3 activity indexes the rapid inhibitory control of ongoing behavior after surprise, as suggested by recent theories. Confirming this prediction, the fronto-central P3 amplitude after both auditory and visual unexpected events was highly correlated with the fronto-central P3 found after stop-signals (measured in a separate stop-signal task). Moreover, surprise-related and stopping-related activity loaded onto the same component in a cross-task independent components analysis. Together, these findings suggest that medial frontal cortex maintains separate predictive models for different sensory domains, but engages a common mechanism for inhibitory control of behavior regardless of the source of surprise.


Assuntos
Lobo Frontal/fisiologia , Estimulação Acústica , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Reflexo de Sobressalto , Análise e Desempenho de Tarefas , Adulto Jovem
18.
Neuroscience ; 414: 154-167, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31310731

RESUMO

Accumulating evidence suggests that glutamatergic signaling and synaptic plasticity underlie one of a number of ways psychiatric disorders appear. The present study reveals a possible mechanism by which this occurs, through highlighting the importance of LMTK3, in the brain. Behavioral analysis of Lmtk3-KO mice revealed a number of abnormalities that have been linked to psychiatric disease such as hyper-sociability, PPI deficits and cognitive dysfunction. Treatment with clozapine suppressed these behavioral changes in Lmtk3-KO mice. As synaptic dysfunction is implicated in human psychiatric disease, we analyzed the LTP of Lmtk3-KO mice and found that induction is severely impaired. Further investigation revealed abnormalities in GluA1 trafficking after AMPA stimulation in Lmtk3-KO neurons, along with a reduction in GluA1 expression in the post-synaptic density. Therefore, we hypothesize that LMTK3 is an important factor involved in the trafficking of GluA1 during LTP, and that disruption of this pathway contributes to the appearance of behavior associated with human psychiatric disease in mice.


Assuntos
Comportamento Animal/fisiologia , Proteínas de Membrana/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de AMPA/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Clozapina/farmacologia , Condicionamento Clássico/efeitos dos fármacos , Condicionamento Clássico/fisiologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/fisiologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Inibição Pré-Pulso/efeitos dos fármacos , Inibição Pré-Pulso/genética , Transporte Proteico/genética , Proteínas Serina-Treonina Quinases/metabolismo , Reconhecimento Psicológico/efeitos dos fármacos , Reconhecimento Psicológico/fisiologia , Reflexo de Sobressalto/efeitos dos fármacos , Reflexo de Sobressalto/genética , Comportamento Social , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia
19.
Behav Neurosci ; 133(5): 517-526, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31246079

RESUMO

Prior studies suggest that levels of ovarian hormones may affect learning and memory in rats, including studies of fear conditioning and extinction. We previously showed that female rats show reduced retention of extinction compared to males when measuring fear-potentiated startle, but not when measuring freezing behavior. One commonly reported observation in studies of freezing behavior is that rats with increased levels of estradiol during extinction learning show better retention of extinction than rats given extinction training when levels of estradiol are low. Here, we tested the hypothesis that fear extinction retention in a fear-potentiated startle paradigm in females is influenced by levels gonadal hormones, which we had not accounted for in our original report. We used the fear-potentiated startle paradigm to test if extinction learning was affected by estrous phase, ovariectomy, or acute systemic injections of estradiol in ovariectomized rats. We report that neither the expression nor extinction of fear-potentiated startle differed in rats given extinction training in proestrus compared to those in metestrus. Removal of the ovaries had no effect on fear acquisition or extinction learning as assessed by fear-potentiated startle. Finally, systemic injections of estradiol given to ovariectomized rats before extinction training had no effect on the expression of fear or the retention of extinction. Our findings suggest that the effect of female gonadal hormones on fear conditioning and extinction may depend on the measure of fear employed or by the parameters used to study fear learning. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Hormônios Gonadais/fisiologia , Animais , Estradiol/farmacologia , Estrogênios/farmacologia , Ciclo Estral/efeitos dos fármacos , Extinção Psicológica/fisiologia , Medo/fisiologia , Feminino , Hormônios Gonadais/metabolismo , Ovariectomia , Ratos , Ratos Sprague-Dawley , Reflexo de Sobressalto/fisiologia
20.
Chin J Physiol ; 62(2): 80-85, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31243178

RESUMO

Prepulse inhibition (PPI) and habituation of the acoustic startle response (ASR) are considered to be effective neurobiological measures of sensorimotor gating and information processing. The deficit of PPI and habituation of ASR has been proposed to be candidate endophenotypes of schizophrenia spectrum disorders. However, there has been little information on PPI and ASR measures in Chinese. The present study aimed to provide more information about the characteristics of PPI and ASR in young healthy Chinese and investigate their sensitivity to experimental parameters and characteristics of population. In this study, we examined the PPI and habituation of ASR in 41 young healthy adults (21 males and 20 females), using an acoustic startle stimulus of 115 dB and a prepulse of 75 dB at a lead interval (LI) of 60 ms and 120 ms, respectively. The behavioral performance demonstrated that the PPI and habituation of ASR in all the young participants were robust. The significant difference was not observed in PPI and habituation between male and female. The block effect on PPI was significant; PPI reduces with increasing training. Latency facilitation was observed under prepulse conditions, with a significant effect of LI. Compared to previous studies in Caucasians, Chinese in this study shows a higher habituation and PPI. In conclusion, this research provides more data of behavioral characteristics of PPI and ASR in young healthy Chinese. Chinese in this study shows a higher habituation and PPI than Caucasians in previous studies.


Assuntos
Inibição Pré-Pulso , Esquizofrenia , Estimulação Acústica , Grupo com Ancestrais do Continente Asiático , Feminino , Humanos , Masculino , Reflexo de Sobressalto
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