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1.
BMC Cancer ; 23(1): 1178, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38041077

RESUMO

BACKGROUND: Many patients treated for breast cancer (BC) complain about cognitive difficulties affecting their daily lives. Recently, sleep disturbances and circadian rhythm disruptions have been brought to the fore as potential contributors to cognitive difficulties in patients with BC. Yet, studies on these factors as well as their neural correlates are scarce. The purpose of the ICANSLEEP-1 (Impact of SLEEP disturbances in CANcer) study is to characterize sleep using polysomnography and its relationship with the evolution of cognitive functioning at both the behavioral and the neuroanatomical levels across treatment in BC patients treated or not with adjuvant chemotherapy. METHODS: ICANSLEEP-1 is a longitudinal study including BC patients treated with adjuvant chemotherapy (n = 25) or not treated with adjuvant chemotherapy (n = 25) and healthy controls with no history of BC (n = 25) matched for age (45-65 years old) and education level. The evaluations will take place within 6 weeks after inclusion, before the initiation of chemotherapy (for BC patients who are candidates for chemotherapy) or before the first fraction of radiotherapy (for BC patients with no indication for chemotherapy) and 6 months later (corresponding to 2 weeks after the end of chemotherapy). Episodic memory, executive functions, psychological factors, and quality of life will be assessed with validated neuropsychological tests and self-questionnaires. Sleep quantity and quality will be assessed with polysomnography and circadian rhythms with both actigraphy and saliva cortisol. Grey and white matter volumes, as well as white matter microstructural integrity, will be compared across time between patients and controls and will serve to further investigate the relationship between sleep disturbances and cognitive decline. DISCUSSION: Our results will help patients and clinicians to better understand sleep disturbances in BC and their relationship with cognitive functioning across treatment. This will aid the identification of more appropriate sleep therapeutic approaches adapted to BC patients. Improving sleep in BC would eventually help limit cognitive deficits and thus improve quality of life during and after treatments. TRIAL REGISTRATION: NCT05414357, registered June 10, 2022. PROTOCOL VERSION: Version 1.2 dated March 23, 2022.


Assuntos
Neoplasias da Mama , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/efeitos adversos , Ritmo Circadiano , Cognição , Estudos Longitudinais , Qualidade de Vida , Sono , Estudos de Casos e Controles
2.
Eur J Neurol ; 29(5): 1293-1302, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35098613

RESUMO

BACKGROUND AND PURPOSE: Repetitive transcranial magnetic stimulation (rTMS) has been proposed to treat functional neurological disorders. Here, the aim was to assess the efficacy of rTMS to treat functional paralysis in a controlled randomized trial. METHODS: Patients received two sessions of active or sham 0.25 Hz rTMS (60 stimuli each), with a 1-day interval, applied over the motor cortex contralateral to the paralysis. The primary outcome was the number of patients with an increase in motor score between baseline and after the second rTMS session, rated by two investigators blinded to the treatment allocation. Secondary outcomes were changes in global and fine motor scores between groups after rTMS, and the occurrence of adverse events. RESULTS: Sixty-two patients (46 female; mean [SD] age, 35.2 [13.9] years) were enrolled and randomized. Thirteen out of 32 (41%) and 11/30 (37%) patients had increased motor strength after active or sham rTMS, respectively (p = 0.80). Changes in both global and fine motor scores after rTMS relative to baseline were also not significantly different between treatment groups (median difference in the global motor score 0.62 [0.83] and 0.37 [0.61], and in the fine motor scores 0.12 [0.18] and 0.08 [0.11], in active and sham rTMS groups, respectively; p = 0.14). Six serious adverse events, consisting of three cephalalgia in the active group and two cephalalgia and one asthenia in the sham group, were observed. CONCLUSIONS: Two sessions of sham or active low frequency rTMS were effective to improve functional paralysis, suggesting a placebo effect of this non-invasive brain stimulation technique.


Assuntos
Córtex Motor , Estimulação Magnética Transcraniana , Adulto , Método Duplo-Cego , Feminino , Cefaleia/etiologia , Humanos , Paralisia/etiologia , Paralisia/terapia , Estimulação Magnética Transcraniana/efeitos adversos , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
3.
Brain ; 143(10): 2957-2972, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32893288

RESUMO

Anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis is a neuropsychiatric disease characterized by an antibody-mediated autoimmune response against NMDAR. Recent studies have shown that anti-NMDAR antibodies are involved in the pathophysiology of the disease. However, the upstream immune and inflammatory processes responsible for this pathogenic response are still poorly understood. Here, we immunized mice against the region of NMDA receptor containing the N368/G369 amino acids, previously implicated in a pathogenic response. This paradigm induced encephalopathy characterized by blood-brain barrier opening, periventricular T2-MRI hyperintensities and IgG deposits into the brain parenchyma. Two weeks after immunization, mice developed clinical symptoms reminiscent of encephalitis: anxiety- and depressive-like behaviours, spatial memory impairment (without motor disorders) and increased sensitivity to seizures. This response occurred independently of overt T-cell recruitment. However, it was associated with B220+ (B cell) infiltration towards the ventricles, where they differentiated into CD138+ cells (plasmocytes). Interestingly, these B cells originated from peripheral lymphoid organs (spleen and cervical lymphoid nodes). Finally, blocking the B-cell response using a depleting cocktail of antibodies reduced the severity of symptoms in encephalitis mice. This study demonstrates that the B-cell response can lead to an autoimmune reaction against NMDAR that drives encephalitis-like behavioural impairments. It also provides a relevant platform for dissecting encephalitogenic mechanisms in an animal model, and enables the testing of therapeutic strategies targeting the immune system in anti-NMDAR encephalitis.


Assuntos
Autoanticorpos/sangue , Linfócitos B/metabolismo , Encefalite/sangue , Doença de Hashimoto/sangue , Proteínas do Tecido Nervoso/toxicidade , Animais , Autoanticorpos/imunologia , Linfócitos B/imunologia , Encefalite/induzido quimicamente , Encefalite/imunologia , Doença de Hashimoto/induzido quimicamente , Doença de Hashimoto/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/imunologia , Receptores de N-Metil-D-Aspartato/imunologia
4.
Brain ; 140(1): 146-157, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28031221

RESUMO

SEE SUN ET AL DOI101093/AWW306 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: About 20% of patients with ischaemic stroke have a preceding transient ischaemic attack, which is clinically defined as focal neurological symptoms of ischaemic origin resolving spontaneously. Failure to diagnose transient ischaemic attack is a wasted opportunity to prevent recurrent disabling stroke. Unfortunately, diagnosis can be difficult, due to numerous mimics, and to the absence of a specific test. New diagnostic tools are thus needed, in particular for radiologically silent cases, which correspond to the recommended tissue-based definition of transient ischaemic attack. As endothelial activation is a hallmark of cerebrovascular events, we postulated that this may also be true for transient ischaemic attack, and that it would be clinically relevant to develop non-invasive in vivo imaging to detect this endothelial activation. Using transcriptional and immunohistological analyses for adhesion molecules in a mouse model, we identified brain endothelial P-selectin as a potential biomarker for transient ischaemic attack. We thus developed ultra-sensitive molecular magnetic resonance imaging using antibody-based microparticles of iron oxide targeting P-selectin. This highly sensitive imaging strategy unmasked activated endothelial cells after experimental transient ischaemic attack and allowed discriminating transient ischaemic attack from epilepsy and migraine, two important transient ischaemic attack mimics. We provide preclinical evidence that combining conventional magnetic resonance imaging with molecular magnetic resonance imaging targeting P-selectin might aid in the diagnosis of transient ischaemic attack.


Assuntos
Ataque Isquêmico Transitório/metabolismo , Imageamento por Ressonância Magnética/métodos , Imagem Molecular/métodos , Selectina-P/metabolismo , Acidente Vascular Cerebral/metabolismo , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Células Endoteliais , Ataque Isquêmico Transitório/diagnóstico por imagem , Masculino , Camundongos , Acidente Vascular Cerebral/diagnóstico por imagem
5.
Glia ; 65(12): 1961-1975, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28850711

RESUMO

Myelination is a late developmental process regulated by a set of inhibitory and stimulatory factors, including extracellular matrix components. Accordingly, chondroitin sulfate proteoglycans (CSPGs) act as negative regulators of myelination processes. A disintegrin and metalloproteinase with thrombospondin motifs type 4 (ADAMTS-4) is an extracellular protease capable of degrading CSPGs. Although exogenous ADAMTS-4 has been proven to be beneficial in several models of central nervous system (CNS) injuries, the physiological functions of endogenous ADAMTS-4 remain poorly understood. We first used Adamts4/LacZ reporter mice to reveal that ADAMTS-4 is strongly expressed in the CNS, especially in the white matter, with a cellular profile restricted to mature oligodendrocytes. Interestingly, we evidenced an abnormal myelination in Adamts4-/- mice, characterized by a higher diameter of myelinated axons with a shifting g-ratio. Accordingly, lack of ADAMTS-4 is accompanied by motor deficits and disturbed nervous electrical activity. In conclusion, we demonstrate that ADAMTS-4 is a new marker of mature oligodendrocytes contributing to the myelination processes and thus to the control of motor capacities.


Assuntos
Proteína ADAMTS4/metabolismo , Transtornos dos Movimentos/genética , Oligodendroglia/metabolismo , Proteína ADAMTS4/genética , Animais , Animais Recém-Nascidos , Proteínas de Ligação ao Cálcio/metabolismo , Corpo Caloso/metabolismo , Corpo Caloso/patologia , Corpo Caloso/ultraestrutura , Modelos Animais de Doenças , Potenciais Somatossensoriais Evocados/genética , Potenciais Somatossensoriais Evocados/fisiologia , Transtornos Neurológicos da Marcha/etiologia , Locomoção/genética , Locomoção/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Proteínas dos Microfilamentos/metabolismo , Microscopia Eletrônica , Transtornos dos Movimentos/fisiopatologia , Proteína Básica da Mielina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Oligodendroglia/patologia , Oligodendroglia/ultraestrutura , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Estatísticas não Paramétricas , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
6.
Sci Rep ; 14(1): 8652, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622265

RESUMO

This research explores different methodologies to modulate the effects of drowsiness on functional connectivity (FC) during resting-state functional magnetic resonance imaging (RS-fMRI). The study utilized a cohort of students (MRi-Share) and classified individuals into drowsy, alert, and mixed/undetermined states based on observed respiratory oscillations. We analyzed the FC group difference between drowsy and alert individuals after five different processing methods: the reference method, two based on physiological and a global signal regression of the BOLD time series signal, and two based on Gaussian standardizations of the FC distribution. According to the reference method, drowsy individuals exhibit higher cortico-cortical FC than alert individuals. First, we demonstrated that each method reduced the differences between drowsy and alert states. The second result is that the global signal regression was quantitively the most effective, minimizing significant FC differences to only 3.3% of the total FCs. However, one should consider the risks of overcorrection often associated with this methodology. Therefore, choosing a less aggressive form of regression, such as the physiological method or Gaussian-based approaches, might be a more cautious approach. Third and last, using the Gaussian-based methods, cortico-subcortical and intra-default mode network (DMN) FCs were significantly greater in alert than drowsy subjects. These findings bear resemblance to the anticipated patterns during the onset of sleep, where the cortex isolates itself to assist in transitioning into deeper slow wave sleep phases, simultaneously disconnecting the DMN.


Assuntos
Mapeamento Encefálico , Sono de Ondas Lentas , Humanos , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Vigília , Sono , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia
7.
Br J Neurosurg ; 27(2): 246-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22998751

RESUMO

Implanted cortical stimulation is foreseen to facilitate functional poststroke recovery. Until now, no study has concluded on its pathophysiological mechanism. We report a case of a 58-year-old patient for whom cortical stimulation triggered a drastic enhancement of speech performances. The effects remain reversible after 6 years of stimulation, reflecting intra/inter-hemispheric modulation.


Assuntos
Afasia de Broca/terapia , Terapia por Estimulação Elétrica/métodos , Acidente Vascular Cerebral/complicações , Afasia de Broca/etiologia , Eletrodos Implantados , Feminino , Humanos , Pessoa de Meia-Idade
8.
Neurobiol Sleep Circadian Rhythms ; 14: 100093, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36974322

RESUMO

The autonomic nervous system (ANS) and the central nervous system (CNS) interplay during sleep, particularly during phasic events such as micro-arousals, has been the subject of several studies. The underlying mechanisms of such relationship which remain unclear, specifically during daytime sleep, were partly investigated in this study. Napping polysomnography was performed on two occasions at least one week apart in 15 healthy subjects. The following cardiorespiratory variables were extracted from the recordings: tachogram, pulse transit time (PTT), pulse wave amplitude, respiratory cycle amplitude, and frequency. Two experts first detected micro-arousal events, then, cardiorespiratory variables were averaged by 30-s epochs over 2 min centered on the onset of the micro-arousals. We found that in the 30 s preceding the arousal events as detected on the electroencephalogram (EEG) recordings, there was a decrease in tachogram, pulse wave amplitude, and PTT values while the respiratory amplitude increased. These changes were more prominent in stage N2 and N3 sleep than in stage N1. The present findings provide new insights into the autonomic changes during the pre-arousal period in daytime naps, as all the variables investigated suggest a sympathetic physiological origin for the changes.

9.
iScience ; 25(12): 105516, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36419855

RESUMO

Intrusive memories hijack consciousness and their control may lead to forgetting. However, the contribution of reflexive attention to qualifying a memory signal as interfering is unknown. We used machine learning to decode the brain's electrical activity and pinpoint the otherwise hidden emergence of intrusive memories reported during a memory suppression task. Importantly, the algorithm was trained on an independent attentional model of visual activity, mimicking either the abrupt and interfering appearance of visual scenes into conscious awareness or their deliberate exploration. Intrusion of memories into conscious awareness were decoded above chance. The decoding accuracy increased when the algorithm was trained using a model of reflexive attention. Conscious detection of intrusive activity decoded from the brain signal was central to the future silencing of suppressed memories and later forgetting. Unwanted memories require the reflexive orienting of attention and access to consciousness to be suppressed effectively by inhibitory control.

10.
BMC Cardiovasc Disord ; 11: 48, 2011 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-21824428

RESUMO

BACKGROUND: The prediction of neurological outcome in comatose patients after cardiac arrest has major ethical and socioeconomic implications. The purpose of this study was to assess the capability of serum neuron-specific enolase (NSE), a biomarker of hypoxic brain damage, to predict death or vegetative state in comatose cardiac-arrest survivors. METHODS: We conducted a prospective observational cohort study in one university hospital and one general hospital Intensive Care Unit (ICU). All consecutive patients who suffered cardiac arrest and were subsequently admitted from June 2007 to February 2009 were considered for inclusion in the study. Patients who died or awoke within the first 48 hours of admission were excluded from the analysis. Patients were followed for 3 months or until death after cardiopulmonary resuscitation. The Cerebral Performance Categories scale (CPC) was used as the outcome measure; a CPC of 4-5 was regarded as a poor outcome, and a CPC of 1-3 a good outcome. Measurement of serum NSE was performed at 24 h and at 72 h after the time of cardiac arrest using an enzyme immunoassay. Clinicians were blinded to NSE results. RESULTS: Ninety-seven patients were included. All patients were actively supported during the first days following cardiac arrest. Sixty-five patients (67%) underwent cooling after resuscitation. At 3 months 72 (74%) patients had a poor outcome (CPC 4-5) and 25 (26%) a good outcome (CPC 1-3). The median and Interquartile Range [IQR] levels of NSE at 24 h and at 72 h were significantly higher in patients with poor outcomes: NSE at 24 h: 59.4 ng/mL [37-106] versus 28.8 ng/mL [18-41] (p < 0.0001); and NSE at 72 h: 129.5 ng/mL [40-247] versus 15.7 ng/mL [12-19] (p < 0.0001). The Receiver Operator Characteristics (ROC) curve for poor outcome for the highest observed NSE value for each patient determined a cut-off value for NSE of 97 ng/mL to predict a poor neurological outcome with a specificity of 100% [95% CI = 87-100] and a sensitivity of 49% [95% CI = 37-60]. However, an approach based on a combination of SSEPs, NSE and clinical-EEG tests allowed to increase the number of patients (63/72 (88%)) identified as having a poor outcome and for whom intensive treatment could be regarded as futile. CONCLUSION: NSE levels measured early in the course of patient care for those who remained comatose after cardiac arrest were significantly higher in patients with outcomes of death or vegetative state. In addition, we provide a cut-off value for NSE (> 97 ng/mL) with 100% positive predictive value of poor outcome. Nevertheless, for decisions concerning the continuation of treatment in this setting, we emphasize that an approach based on a combination of SSEPs, NSE and clinical EEG would be more accurate for identifying patients with a poor neurological outcome.


Assuntos
Coma/diagnóstico , Coma/enzimologia , Parada Cardíaca/diagnóstico , Parada Cardíaca/enzimologia , Fosfopiruvato Hidratase/sangue , Adulto , Idoso , Biomarcadores/sangue , Estudos de Coortes , Coma/mortalidade , Feminino , Parada Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Taxa de Sobrevida/tendências , Resultado do Tratamento
11.
Acta Neurochir (Wien) ; 152(10): 1653-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20563609

RESUMO

PURPOSE: Surgical treatment of cavernomas arising in the insula (especially in dominant cerebral hemisphere) is challenging in reason of the proximity to the internal capsule and lenticulostriate arteries. The advent of image guidance systems and intraoperative mapping of the subcortical language pathways has broadened the surgical indications for these lesions. In this work, we report four cases of insular cavernomas operated on, and we define a surgical strategy for these lesions. METHODS: Between July 1997 and May 2007 in our department, four patients harboring an insular cavernoma were operated on by using image guidance system (neuronavigation in three cases, ultrasound in one case). Subcortical stimulations were used to preserve the functional language area in one case. FINDINGS: The image guidance system determined the exact planning of the approach and determination of the ideal trajectory of insular cortex dissection. In a case of a deep left insular cavernoma, the shortest approach to remove the cavernoma was stopped in per-operative time because subcortical stimulation produced a speech inhibition, justifying another insular corticotomy. No surgical complications occurred, and the postoperative course was uneventful in all patients. CONCLUSION: As it has been proposed by many authors, image guidance system is recommended in surgery of insular cavernomas. When the lesion is located in the dominant hemisphere, intraoperative mapping of the subcortical language pathways is also indicated to preserve the language functional areas.


Assuntos
Neoplasias Encefálicas/cirurgia , Córtex Cerebral/cirurgia , Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Neuronavegação/métodos , Procedimentos Neurocirúrgicos/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Feminino , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico por imagem , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia
12.
Sci Rep ; 10(1): 15008, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929105

RESUMO

Efforts to exclude past experiences from conscious awareness can lead to forgetting. Memory suppression is central to affective disorders, but we still do not really know whether emotions, including their physiological causes, are also impacted by this process in normal functioning individuals. In two studies, we measured the after-effects of suppressing negative memories on cardiac response in healthy participants. Results of Study 1 revealed that efficient control of memories was associated with long-term inhibition of the cardiac deceleration that is normally induced by disgusting stimuli. Attempts to suppress sad memories, by contrast, aggravated the cardiac response, an effect that was closely related to the inability to forget this specific material. In Study 2, electroencephalography revealed a reduction in power in the theta (3-8 Hz), alpha (8-12 Hz) and low-beta (13-20 Hz) bands during the suppression of unwanted memories, compared with their voluntary recall. Interestingly, however, the reduction of power in the theta frequency band during memory control was related to a subsequent inhibition of the cardiac response. These results provide a neurophysiological basis for the influence of memory control mechanisms on the cardiac system, opening up new avenues and questions for treating intrusive memories using motivated forgetting.


Assuntos
Emoções/fisiologia , Coração/fisiologia , Memória/fisiologia , Adolescente , Adulto , Eletroencefalografia , Feminino , Frequência Cardíaca , Humanos , Masculino , Experimentação Humana não Terapêutica , Fatores de Tempo , Adulto Jovem
13.
Exp Brain Res ; 196(2): 295-301, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19479247

RESUMO

In order to explore the effect of gaze orientation on whole-body rotation perception, ten healthy participants were rotated in the dark while fixating on a visual target located either straight ahead or 15 degrees to the right. A vestibular-memory contingent saccade paradigm was used to estimate the rotation perception. The results attest to the participants' ability to accurately perceive their rotation, based solely on the intrinsic inputs (somesthetic and mainly vestibular), since the correlation between the imposed body rotation and the saccade amplitude was significant and positive. However, the rotation perception was less accurate and of lesser magnitude when the gaze was deviated in the opposite direction to the rotation than when it was either straight ahead or deviated in the direction of the rotation. This can be interpreted as the perceptual equivalent of Alexander's law.


Assuntos
Fixação Ocular , Movimento (Física) , Orientação , Percepção , Rotação , Análise de Variância , Escuridão , Feminino , Humanos , Modelos Lineares , Masculino , Psicofísica , Adulto Jovem
14.
Neuropsychiatr Dis Treat ; 15: 2105-2117, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413576

RESUMO

PURPOSE: This review reports the current perspectives of brain stimulation techniques in the treatment of auditory verbal hallucinations (AVH) in schizophrenia. METHODS: A systematic search of the literature in the PubMed database revealed that the most studied techniques are noninvasive techniques (NIBS), including electroconvulsive therapy (ECT), transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS). RESULTS: The results showed that ECT could have great clinical efficacy but is currently underused in practice perhaps due to the costs associated with its limited implementation and potential associated risks. tDCS is still poorly studied and does not demonstrate sufficiently homogeneous or conclusive results yet to prove its efficacy in the treatment of AVH. However, its safe and simple implementation allows us to recommend it to patients who are refractory to other stimulation techniques. Finally, rTMS seems to be the most efficacious NIBS to offer patients with persistent AVH as an add-on therapeutic strategy. Its implementation has a non negligible cost but can be performed by a single practitioner. Great evolution in these techniques with technological progress, robotics and computer science are currently being tested and will undoubtedly improve the clinical efficacy of these procedures, particularly towards more personalized treatments such as individual rTMS targets and intensities. There are also new techniques for deep brain stimulation based on focused ultrasound that could provide much insight into the treatment of AVH in schizophrenia. CONCLUSION: This review suggests that add-on brain stimulation treatments could play a key role among the therapeutic strategies for auditory hallucinations reduction in schizophrenia.

15.
Cortex ; 117: 111-121, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30959421

RESUMO

Since reasoning is often biased by intuitive heuristics, the development of sound reasoning has long been postulated to depend on successful bias monitoring and inhibition. The present fMRI study aimed to identify neural correlates of developmental changes in these processes. A group of adults and young adolescents were presented with ratio-bias problems in which an intuitively cued heuristic response could be incongruent (conflict item) or congruent (no-conflict item) with the correct response. Results showed that successfully avoiding biased responding on conflict items across both age groups was associated with increased activation in Anterior Cingulate Cortex (ACC) and the right Lateral Prefrontal Cortex (LPFC) regions of interest. Critically, the right LPFC activation decreased with age. Biased responding did not result in right LPFC or ACC modulation and failed to show any developmental activation changes. We discuss implications for ongoing debates on the nature of heuristic bias and its development.


Assuntos
Envelhecimento/psicologia , Cognição/fisiologia , Giro do Cíngulo/diagnóstico por imagem , Inibição Psicológica , Córtex Pré-Frontal/diagnóstico por imagem , Resolução de Problemas/fisiologia , Adolescente , Adulto , Conflito Psicológico , Feminino , Heurística , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tempo de Reação/fisiologia , Adulto Jovem
16.
Neuroreport ; 19(5): 565-8, 2008 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-18388739

RESUMO

The aim of this study was to investigate whether figure skaters, as individuals who experience intense vestibular stimulation, presented modification of the otolith-ocular reflex. The reflexes of 12 figure skaters were assessed using off vertical axis rotation (OVAR). Horizontal otolith-ocular reflex during OVAR is characterized by two parameters: the eye velocity horizontal modulation, assumed to compensate for perceived lateral linear translation, and the bias, assumed to compensate for the perceived rotation. We observed that skaters presented smaller amplitude of modulation and truly compensatory bias compared with control participants. Thus, the otolithic signal during OVAR seems to be interpreted more as rotation and less as translation or inclination in figure skaters.


Assuntos
Percepção de Movimento/fisiologia , Membrana dos Otólitos/fisiologia , Reflexo Vestíbulo-Ocular/fisiologia , Patinação/fisiologia , Adolescente , Adulto , Análise de Variância , Criança , Eletroculografia , Feminino , Gravitação , Sensação Gravitacional/fisiologia , Humanos , Masculino , Nistagmo Optocinético/fisiologia , Testes de Função Vestibular/métodos
17.
BMC Cardiovasc Disord ; 8: 35, 2008 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-19055810

RESUMO

BACKGROUND: Anoxic coma following cardiac arrest is a common problem with ethical, social, and legal consequences. Except for unfavorable somatosensory-evoked potentials (SSEP) results, predictors of unfavorable outcome with a 100% specificity and a high sensitivity are lacking. The aim of the current research was to construct a clinical and EEG scoring system that predicts early cortical response (N20) to somatosensory evoked potentials and 6-months outcome in comatose patients after cardiac arrest. METHODS: We retrospectively reviewed the records of all consecutive patients who suffered cardiac arrest outside our hospital and were subsequently admitted to our facility from November 2002 to July 2006. We scored each case based on early clinical and EEG factors associated with unfavorable SSEPs, and we assessed the ability of this score to predict SSEP results and outcome. RESULTS: Sixty-six patients qualified for inclusion in the cohort. Among them, 34 (52%) had unfavorable SSEP results. At day three, factors independently associated with unfavorable SSEPs were: absence of corneal (14 points) and pupillary (21 points) reflexes, myoclonus (25 points), extensor or absent motor response to painful stimulation (28 points), and malignant EEG (11 points). A score >40 points had a sensitivity of 85%, a specificity of 84%, and a positive predictive value (PPV) of 85% to predict unfavorable SSEP results. A score >88 points had a PPV of 100%, but a sensitivity of 18%. Overall, this score had an area under ROC curves of 0.919. In addition, at day three, a score > 69 points had a PPV of 100% with a sensitivity of 32% to predict death or vegetative state. CONCLUSION: A scoring system based on a combination of clinical and EEG findings can predict the absence of early cortical response to SSEPs. In settings without access to SSEPs, this score may help decision-making in a subset of comatose survivors after a cardiac arrest.


Assuntos
Coma/diagnóstico , Eletroencefalografia/métodos , Estado Vegetativo Persistente/diagnóstico , Idoso , Piscadela , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Coma/etiologia , Coma/fisiopatologia , Potenciais Somatossensoriais Evocados/fisiologia , Feminino , Parada Cardíaca/complicações , Parada Cardíaca/fisiopatologia , Humanos , Hipóxia Encefálica/etiologia , Hipóxia Encefálica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estado Vegetativo Persistente/etiologia , Estado Vegetativo Persistente/fisiopatologia , Valor Preditivo dos Testes , Prognóstico , Reflexo Pupilar , Estudos Retrospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença
18.
Neurosci Lett ; 686: 198-204, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30219485

RESUMO

Long-latency auditory event potentials (LLAEPs) involving local and global auditory processes have been investigated to examine the impact of low-frequency (LF) and high-frequency (HF) repetitive transcranial magnetic stimulation (rTMS) on the cortical excitability of the temporal cortex. We hypothesized that both stimulation frequencies have the same modulation effect, in accordance with clinical data showing a reduction in auditory verbal hallucinations (AVHs) after LF and HF temporal rTMS in patients with schizophrenia. With 30 right-handed healthy volunteer participants enrolled in a crossover trial, we analyzed LLAEPs before and after LF- and HF-rTMS of the left temporal cortex. While we observed no changes in latencies, we did observe a similar inhibitory action of both rTMS frequencies on LLAEP amplitudes. Analysis of surface potential maps and cortical generators revealed some differences regarding auditory processes: HF-rTMS produced earlier, more diffuse, and more right-lateralized effects than LF-rTMS. Beyond a local impact, rTMS exerted a remote modulation influence on the frontal cortex that might be involved in attentional processes. This association could explain the therapeutic effect of temporal HF-rTMS on AVH.


Assuntos
Potenciais Evocados Auditivos/fisiologia , Alucinações/fisiopatologia , Esquizofrenia/terapia , Estimulação Magnética Transcraniana , Adulto , Atenção/fisiologia , Córtex Cerebral/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/fisiopatologia , Lobo Temporal/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Adulto Jovem
19.
eNeuro ; 5(1)2018.
Artigo em Inglês | MEDLINE | ID: mdl-29527565

RESUMO

Inhibitory control (IC) is a core executive function that enables humans to resist habits, temptations, or distractions. IC efficiency in childhood is a strong predictor of academic and professional success later in life. Based on analysis of the sulcal pattern, a qualitative feature of cortex anatomy determined during fetal life and stable during development, we searched for evidence that interindividual differences in IC partly trace back to prenatal processes. Using anatomical magnetic resonance imaging (MRI), we analyzed the sulcal pattern of two key regions of the IC neural network, the dorsal anterior cingulate cortex (ACC) and the inferior frontal cortex (IFC), which limits the inferior frontal gyrus. We found that the sulcal pattern asymmetry of both the ACC and IFC contributes to IC (Stroop score) in children and adults: participants with asymmetrical ACC or IFC sulcal patterns had better IC efficiency than participants with symmetrical ACC or IFC sulcal patterns. Such additive effects of IFC and ACC sulcal patterns on IC efficiency suggest that distinct early neurodevelopmental mechanisms targeting different brain regions likely contribute to IC efficiency. This view shares some analogies with the "common variant-small effect" model in genetics, which states that frequent genetic polymorphisms have small effects but collectively account for a large portion of the variance. Similarly, each sulcal polymorphism has a small but additive effect: IFC and ACC sulcal patterns, respectively, explained 3% and 14% of the variance of the Stroop interference scores.


Assuntos
Função Executiva , Lobo Frontal/anatomia & histologia , Giro do Cíngulo/anatomia & histologia , Inibição Psicológica , Adulto , Envelhecimento , Criança , Lobo Frontal/crescimento & desenvolvimento , Humanos , Individualidade , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Adulto Jovem
20.
Schizophr Bull ; 44(3): 505-514, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29897597

RESUMO

INTRODUCTION: Despite extensive testing, the efficacy of low-frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) of temporo-parietal targets for the treatment of auditory verbal hallucinations (AVH) in patients with schizophrenia is still controversial, but promising results have been reported with both high-frequency and neuronavigated rTMS. Here, we report a double-blind sham-controlled study to assess the efficacy of high-frequency (20 Hz) rTMS applied over a precise anatomical site in the left temporal region using neuronavigation. METHODS: Fifty-nine of 74 randomized patients with schizophrenia or schizoaffective disorders (DSM-IV R) were treated with rTMS or sham treatment and fully evaluated over 4 weeks. The rTMS target was determined by morphological MRI at the crossing between the projection of the ascending branch of the left lateral sulcus and the superior temporal sulcus (STS). RESULTS: The primary outcome was response to treatment, defined as a 30% decrease of the Auditory Hallucinations Rating Scale (AHRS) frequency item, observed at 2 successive evaluations. While there was no difference in primary outcome between the treatment groups, the percentages of patients showing a decrease of more than 30% of AHRS score (secondary outcome) did differ between the active (34.6%) and sham groups (9.1%) (P = .016) at day 14. DISCUSSION: This controlled study reports negative results on the primary outcome but demonstrates a transient effect of 20 Hz rTMS guided by neuronavigation and targeted on an accurate anatomical site for the treatment of AVHs in schizophrenia patients.


Assuntos
Alucinações/terapia , Avaliação de Resultados em Cuidados de Saúde , Transtornos Psicóticos/terapia , Esquizofrenia/terapia , Lobo Temporal/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Adulto , Método Duplo-Cego , Feminino , Alucinações/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuronavegação/métodos , Transtornos Psicóticos/complicações , Esquizofrenia/complicações
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