Systematization, distribution and territory of the caudal cerebral artery on the brain's surface of the turkey (Meleagris gallopavo)

Thirty Meleagris gallopavo heads with their neck segments were used. Animals were contained and euthanized with the association of mebezonium iodide, embutramide and tetracaine hydrochloride (T 61, Intervet ) by intravenous injection. The arterial system was rinsed with cold saline solution (15°C), with 5000IU heparin and filled with red-colored latex. The samples were fixed in 20% formaldehyde for seven days. The brains were removed with a segment of cervical spinal cord and after, the dura-mater was removed and the arteries dissected. The cerebral carotid arteries, after the intercarotid anastomosis, were projected around the hypophysis, until they reached the tuber cinereum and divided into their terminal branches, the caudal branch and the rostral branch. The rostral branch was projected rostrolateralwards and gave off, in sequence, two collateral branches, the caudal cerebral and the middle cerebral arteries and the terminal branch was as cerebroethmoidal artery. The caudal cerebral artery of one antimere formed the interhemispheric artery, which gave off dorsal hemispheric branches to the convex surface of both antimeres. Its dorsal tectal mesencephalic branch, of only one antimere, originated the dorsal cerebellar artery. In the interior of the cerebral transverse fissure, after the origin of the dorsal tectal mesencephalic artery, the caudal cerebral artery emitted occipital hemispheric branches, pineal branches and medial hemispheric branches, on both antimeres. The caudal cerebral artery's territory comprehended the entire surface of the dorsal hemioptic lobe, the rostral surface of the cerebellum, the diencephalic structures, the caudal pole and the medial surface of the cerebral hemisphere and in the convex surface, the sagittal eminence except for its most rostral third. Due to the asymmetry found in the caudal cerebral arteries' ramifications, the models were classified into three types and their respective subtypes.

Osteologia do neurocrânio de Iguana iguana iguana (Squamata: Iguanidae)

Resumo: O crânio representa o segmento com conspícuas adaptações que, nos lagartos, podem ser conservativas ou impulsionadas por pressões seletivas. Objetivando subsidiar o conhecimento morfológico dos répteis, fornecemos uma descrição detalhada dos ossos que formam o neurocrânio de Iguana iguana iguana com base na análise de três esqueletos secos de espécimes adultos. O crânio da referia espécie possui características basais entre os lagartos sem o fechamento das aberturas cranianas e formato geral triangular. As estruturas ósseas que formam a base craniana apresentam muitas fusões, principalmente no assoalho. Na face caudal o exoccipital e o opistótico estão fundidos e formam o otoccipital, que contribui para a formação dos terços laterais do côndilo occipital. A parte central do côndilo é formada pelo supraoccipital. Fusões e estruturas esqueléticas presentes em Iguana são similares aos demais lagartos. Não foram descritas autapomorfias no neurocrânio para esta espécie.

Deficiências minerais em vacas em lactação da bacia leiteira do município de Rondon do Pará, estado do Pará

ResumoRealizou-se um estudo das deficiências minerais em vacas em lactação de rebanhos leiteiros pertencentes a 13 propriedades da bacia leiteira do município de Rondon do Pará, estado do Pará. Foram determinados os níveis de fósforo (P) no osso, e os níveis de cobre (Cu), cobalto (Co), selênio (Se) e zinco (Zn) no fígado de 47 vacas leiteiras no 2º terço da lactação. Estas amostras foram coletadas por meio de biópsias realizadas no terço superior da 12a costela do lado direito e no bordo caudal do lobo caudado do fígado, respectivamente. Os rebanhos eram formados por animais mestiços (Holandes x Zebu), mantidos em sistema de produção extensivo em pastos de Brachiaria brizantha cv Marandu e recebiam suplementação mineral. A mistura mineral em 12 propriedades era do tipo comercial, dita "completa", acrescida de quantidades de NaCl acima do recomendado pelos fabricantes em dez propriedades. Em sete propriedades as misturas minerais eram fornecidas em cochos sem cobertura e em oito, o fornecimento da mistura mineral não era realizado diariamente. Em 11 propriedades, havia históricos clínicos condizentes com deficiências minerais nos rebanhos. Nessas fazendas a retenção de placenta e a osteofagia foram as alterações mais relatadas. Após as análises minerais observou-se deficiência de P em cinco propriedades, de Co em três propriedades, de Se em nove propriedades e de Zn em dez propriedades. Conclui-se que ocorre a deficiência de P, Co, Se e Zn; a suplementação mineral realizada na maioria das propriedades não atendeu as exigências diárias de P, Se e Co, baseadas no consumo estimado de 30 g de NaCl/animal/dia; os cochos pouco adequados ou inadequados para a suplementação, assim como o fornecimento inconstante das misturas minerais possivelmente contribuíram para a deficiência de um ou mais minerais.

Comparação de dois métodos de colheita de medula óssea de equinos e de dois meios de diluição para o isolamento de células mononucleares

Resumo: O objetivo do presente estudo foi avaliar a concentração e viabilidade da fração de células mononucleares (FCM) a partir de diferentes técnicas de colheita e processamento de medula óssea (MO) em equinos. Foram avaliados cinco equinos adultos, hígidos e sem raça definida. Obtiveram-se frações de medula óssea (MO) do osso esterno, de acordo com dois protocolos: na colheita A, utilizou-se 10mL de solução de heparina dentro da seringa e em seguida, aspirou-se a MO; na colheita B, 10mL de solução de heparina foi injetada na MO e a aspiração foi realizada após 20 segundos. Todos os animais foram submetidos aos dois protocolos de colheitas, realizadas em sequência, sem intervalo entre os dois procedimentos. Após isolamento da fração de células mononucleares (FCM), das amostras de MO obtidas nas colheitas A e B, cada amostra foi dividida em dois tubos, um contendo solução de DMEM e outro contendo PBS. Assim, alternando-se o tipo de colheita e a solução diluidora, obteve-se quatro tubos de amostras por animal. Os tubos foram centrifugados e os sedimentos foram homogeneizados nos respectivos meios obtendo-se o volume final de 100μL. Realizou-se determinação da concentração e viabilidade celular, obtendo-se as concentrações médias de FCM. Para ambos os meios de diluição, a colheita B apresentou valor numérico maior em comparação à colheita A, porém não foi significativo (p>0,05). Atribui-se tal tendência à menor ocorrência de coagulação da MO no momento da colheita B, sugerindo-se melhor aproveitamento da FCM. Não houve diferença (p>0,05) entre os meios DMEM ou PBS, indicando que os mesmos não alteraram a viabilidade celular. Os protocolos utilizados para colheita de MO e separação da FCM se mostraram eficientes, para o uso em terapia celular em equinos.

Floristic and vegetation structure of a granitic grassland in Southern Brazil

A floristic and structural survey of a natural grassland community was conducted on Morro do Osso, a granitic hill in Porto Alegre, RS, Brazil. Structural data were surveyed in 39 one square meter plots placed over two major grassland areas. An accidental fire has occurred in one of the areas approximately one year prior to our survey, leading to further analysis of parameters differences between sites. The floristic list contains 282 species, whereas the structural survey has found 161 species. Families with highest accumulated importance values were Poaceae, Asteraceae and Fabaceae. The diversity and evenness indexes were 4.51 nats ind-1 and 0.86, respectively. Cluster analysis denoted two groups coinciding with the areas distinguished by the fire disturbance. A similarity analysis between our data and two other data sets from nearby granitic hills resulted in 28% to 35% similarity, with equivalent species-family distribution and many common dominant species, corroborating the concept of a continuous flora along the South Brazilian granitic hills.

The neural processes generating visual phenomenal consciousness: ERP and neuronavigated brain stimulation studies

One of the greatest conundrums to the contemporary science is the relation between consciousness and brain activity, and one of the specifi c questions is how neural activity can generate vivid subjective experiences. Studies focusing on visual consciousness have become essential in solving the empirical questions of consciousness. Th e main aim of this thesis is to clarify the relation between visual consciousness and the neural and electrophysiological processes of the brain. By applying electroencephalography and functional magnetic resonance image-guided transcranial magnetic stimulation (TMS), we investigated the links between conscious perception and attention, the temporal evolution of visual consciousness during stimulus processing, the causal roles of primary visual cortex (V1), visual area 2 (V2) and lateral occipital cortex (LO) in the generation of visual consciousness and also the methodological issues concerning the accuracy of targeting TMS to V1. Th e results showed that the fi rst eff ects of visual consciousness on electrophysiological responses (about 140 ms aft er the stimulus-onset) appeared earlier than the eff ects of selective attention, and also in the unattended condition, suggesting that visual consciousness and selective attention are two independent phenomena which have distinct underlying neural mechanisms. In addition, while it is well known that V1 is necessary for visual awareness, the results of the present thesis suggest that also the abutting visual area V2 is a prerequisite for conscious perception. In our studies, the activation in V2 was necessary for the conscious perception of change in contrast for a shorter period of time than in the case of more detailed conscious perception. We also found that TMS in LO suppressed the conscious perception of object shape when TMS was delivered in two distinct time windows, the latter corresponding with the timing of the ERPs related to the conscious perception of coherent object shape. Th e result supports the view that LO is crucial in conscious perception of object coherency and is likely to be directly involved in the generation of visual consciousness. Furthermore, we found that visual sensations, or phosphenes, elicited by the TMS of V1 were brighter than identically induced phosphenes arising from V2. Th ese fi ndings demonstrate that V1 contributes more to the generation of the sensation of brightness than does V2. Th e results also suggest that top-down activation from V2 to V1 is probably associated with phosphene generation. The results of the methodological study imply that when a commonly used landmark (2 cm above the inion) is used in targeting TMS to V1, the TMS-induced electric fi eld is likely to be highest in dorsal V2. When V1 was targeted according to the individual retinotopic data, the electric fi eld was highest in V1 only in half of the participants. Th is result suggests that if the objective is to study the role of V1 with TMS methodology, at least functional maps of V1 and V2 should be applied with computational model of the TMS-induced electric fi eld in V1 and V2. Finally, the results of this thesis imply that diff erent features of attention contribute diff erently to visual consciousness, and thus, the theoretical model which is built up of the relationship between visual consciousness and attention should acknowledge these diff erences. Future studies should also explore the possibility that visual consciousness consists of several processing stages, each of which have their distinct underlying neural mechanisms.

Behavioral and electroencephalographic analysis of seizures induced by intrahippocampal injection of granulitoxin, a neurotoxic peptide from the sea anemone Bunodosoma granulifera

In this study, the behavioral and electroencephalographic (EEG) analysis of seizures induced by the intrahippocampal injection in rats of granulitoxin, a neurotoxic peptide from the sea anemone Bunodosoma granulifera, was determined. The first alterations occurred during microinjection of granulitoxin (8 µg) into the dorsal hippocampus and consisted of seizure activity that began in the hippocampus and spread rapidly to the occipital cortex. This activity lasted 20-30 s, and during this period the rats presented immobility. During the first 40-50 min after its administration, three to four other similar short EEG seizure periods occurred and the rats presented the following behavioral alterations: akinesia, facial automatisms, head tremor, salivation, rearing, jumping, barrel-rolling, wet dog shakes and forelimb clonic movements. Within 40-50 min, the status epilepticus was established and lasted 8-12 h. These results are similar to those observed in the acute phase of the pilocarpine model of temporal lobe epilepsy and suggest that granulitoxin may be a useful tool not only to study the sodium channels, but also to develop a new experimental model of status epilepticus.

Photic driving in the electroencephalogram of children and adolescents: harmonic structure and relation to the resting state

In order to identify latent bioelectrical oscillators, 15 normal subjects (aged 9-17 years, 8 males, 7 females) were subjected to intermittent photic stimulation. The EEG amplitude spectra corresponding to the 11 fixed frequencies of stimulation presented (3-24 Hz) were combined to form "profiles" of the driving reaction in the right occipital area. The driving response varied with frequency, and was demonstrable in 70-100% of cases (using as criterion peak amplitudes 20% larger than those of the neighbors). The strongest responses were observed at the frequency closest to the alpha peak of the resting EEG. A secondary profile maximum was in the theta band. In 10 subjects, this maximum exceeded half the alpha peak (with an average of 72.4% of the alpha peak), while in the resting spectra, theta amplitudes were much lower than the alpha maxima. This responsiveness in theta activity seems to be characteristic of prepubertal and pubertal subjects. The profiles and resting EEG spectra showed a highly significant Pearson's correlation, with the peak in the theta band of the profiles being the main difference observed between them. The correlation coefficient was significantly correlated with the ratio of the maxima in the theta and alpha bands (R = -0.77, P<0.001). The correlation coefficient between profile and resting spectrum may be a useful indicator in screening methods used to reveal latent cerebral oscillators. Profiles for the second and third harmonics were correlated with those of the first harmonic (fundamental frequency), when considering the corresponding EEG frequencies. Peak frequencies in all three profiles were close to those of the individual's background alpha rhythm, and peak amplitudes in higher harmonics were not much lower than those of the fundamental frequency (mean values of 84 and 63%, for second and third harmonics, respectively).

Topographic aspects of photic driving in the electroencephalogram of children and adolescents

The electroencephalogram amplitude spectra at 11 fixed frequencies of intermittent photic stimulation of 3 to 24 Hz were combined into driving "profiles" for 14 scalp points in 8 male and 7 female normal subjects aged 9 to 17 years. The driving response varied over frequency and was detected in 70 to 100% of cases in the occipital areas (maximum) and in 27 to 77% of cases in the frontal areas (minimum) using as a criterion peak amplitude 20% higher than those of the neighbors. Each subject responded, on average, to 9.7 ± 1.15 intermittent photic stimulation frequencies in the right occipital area and to 6.8 ± 1.97 frequencies in the right frontal area. Most of the driving responses (in relation to the previous background) were significant according to the spectral F-test (a = 0.05), which also detected changes in some cases of low amplitude responses not revealed by the peak criterion. The profiles had two maxima in the alpha and theta bands in all leads. The latter was not present in the background spectra in the posterior areas and was less pronounced in the anterior ones. The weight of the profile theta maximum increased towards the frontal areas where the two maxima were similar, while the profile amplitudes decreased. The profiles repeated the shape of the background spectra, except for the theta band. The interhemispheric correlation between profiles was high. The theta driving detected in all areas recorded suggests a generalized influence of the theta generators in prepubertal and pubertal subjects.

Central 5-HT2A receptors modulate the vagal bradycardia in response to activation of the von Bezold-Jarisch reflex in anesthetized rats

Activation of 5-hydroxytryptamine (5-HT) 5-HT1A, 5-HT2C, 5-HT3, and 5-HT7 receptors modulates the excitability of cardiac vagal motoneurones, but the precise role of 5-HT2A/2B receptors in these phenomena is unclear. We report here the effects of intracisternal (ic) administration of selective 5-HT2A/2B antagonists on the vagal bradycardia elicited by activation of the von Bezold-Jarisch reflex with phenylbiguanide. The experiments were performed on urethane-anesthetized male Wistar rats (250-270 g, N = 7-9 per group). The animals were placed in a stereotaxic frame and their atlanto-occipital membrane was exposed to allow ic injections. The rats received atenolol (1 mg/kg, iv) to block the sympathetic component of the reflex bradycardia; 20-min later, the cardiopulmonary reflex was induced with phenylbiguanide (15 µg/kg, iv) injected at 15-min intervals until 3 similar bradycardias were obtained. Ten minutes after the last pre-drug bradycardia, R-96544 (a 5-HT2A antagonist; 0.1 µmol/kg), SB-204741 (a 5-HT2B antagonist; 0.1 µmol/kg) or vehicle was injected ic. The subsequent iv injections of phenylbiguanide were administered 5, 20, 35, and 50 min after the ic injection. The selective 5-HT2A receptor antagonism attenuated the vagal bradycardia and hypotension, with maximal effect at 35 min after the antagonist (pre-drug = -200 ± 11 bpm and -42 ± 3 mmHg; at 35 min = -84 ± 10 bpm and -33 ± 2 mmHg; P < 0.05). Neither the 5-HT2B receptor antagonists nor the vehicle changed the reflex. These data suggest that central 5-HT2A receptors modulate the central pathways of the parasympathetic component of the von Bezold-Jarisch reflex.

Qualidade nutricional e escore químico de aminoácidos de diferentes fontes protéicas

As proteínas são moléculas essenciais para aos organismos animais, devendo, portanto, estar presentes na alimentação em quantidades adequadas. Além do aspecto quantitativo deve-se levar em conta o aspecto qualitativo, isto é, seu valor nutricional, que dependerá de sua composição, digestibilidade, biodisponibilidade de aminoácidos essenciais, ausência de toxicidade e de fatores antinutricionais. O objetivo deste trabalho foi avaliar a digestibilidade in vivo, o escore químico de aminoácidos (EQ) e o escore químico de aminoácido corrigido pela digestibilidade protéica (PDCAAS) das seguintes fontes de proteína: carne de rã sem osso, carne de rã com osso, carne de rã mecanicamente separada (CMS), carne bovina, ovo em pó, caseína, trigo, milho, soja convencional, soja isenta de inibidor de tripsina Kunitz e de lipoxigenases (soja KTI-LOX-), proteína texturizada de soja (PTS) e feijão. As proteínas de origem animal apresentaram maiores valores de digestibilidade que as de origem vegetal. Carne de rã sem osso apresentou a proteína com maior digestibilidade protéica de todas as proteínas estudadas, não diferindo, entretanto, da caseína, CMS, carne bovina e rã com osso. Das proteínas de origem animal, a do ovo em pó foi aquela que apresentou menor digestibilidade protéica. Nenhuma das proteínas de origem animal apresentou aminoácidos essenciais limitantes quando comparadas com o padrão da FAO/WHO. Feijão, soja convencional, soja KTI-LOX- e PTS, tiveram os aminoácidos sulfurados (metionina+cisteína) como limitantes. Enquanto que para trigo e milho, o aminoácido mais limitante foi a lisina. Soja KTI-LOX- e PTS apresentaram valores de PDCAAS superiores aos da soja convencional, mostrando uma possível elevação na qualidade protéica da soja melhorada geneticamente e da soja processada.

Atividade de água, pH, umidade e desenvolvimento de Staphylococcus xylosus durante o processamento e armazenamento da paleta suína curada, maturada e fermentada

Dez peças de paletas suínas sem pele e sem osso, pesando em média 1,6 kg, receberam injeção de salmoura (20% p.v -1) contendo cultura de Staphylococcus xylosus e permaneceram dentro de uma câmara durante 30 dias à temperatura de 4 a 9 °C e umidade de 55 a 45% controladas. Em seguida, foram embaladas a vácuo e armazenadas durante 120 dias a 10 °C. Desde o início da produção até o final do armazenamento, as amostras foram coletadas da superfície e da parte interna das peças de paleta suína, em triplicata, para realização das análises de atividade de água, pH, umidade e contagem da cultura de S. xylosus, com objetivo de caracterizá-las e verificar as possíveis associações com ações exercidas em outros produtos cárneos fermentados. Durante a etapa de armazenamento, os valores de umidade e pH obtidos na parte interna dos tratamentos ficaram dentro dos parâmetros recomendados para presunto curado. A cultura adicionada apresentou melhor desenvolvimento na parte interna da paleta. A temperatura de armazenamento recomendada para a paleta seria entre 5 e 10 °C, uma vez que os valores de pH foram maiores que 5,2 e os de a w menores que 0,91.

Electrophysiological constituents of the P100 and N170 ERP complex: De-constructing of face processing using independent component analysis and robust estimation.

The initial timing of face-specific effects in event-related potentials (ERPs) is a point of contention in face processing research. Although effects during the time of the N170 are robust in the literature, inconsistent effects during the time of the P100 challenge the interpretation of the N170 as being the initial face-specific ERP effect. The interpretation of the early P100 effects are often attributed to low-level differences between face stimuli and a host of other image categories. Research using sophisticated controls for low-level stimulus characteristics (Rousselet, Husk, Bennett, & Sekuler, 2008) report robust face effects starting at around 130 ms following stimulus onset. The present study examines the independent components (ICs) of the P100 and N170 complex in the context of a minimally controlled low-level stimulus set and a clear P100 effect for faces versus houses at the scalp. Results indicate that four ICs account for the ERPs to faces and houses in the first 200ms following stimulus onset. The IC that accounts for the majority of the scalp N170 (icNla) begins dissociating stimulus conditions at approximately 130 ms, closely replicating the scalp results of Rousselet et al. (2008). The scalp effects at the time of the P100 are accounted for by two constituent ICs (icP1a and icP1b). The IC that projects the greatest voltage at the scalp during the P100 (icP1a) shows a face-minus-house effect over the period of the P100 that is less robust than the N 170 effect of icN 1 a when measured as the average of single subject differential activation robustness. The second constituent process of the P100 (icP1b), although projecting a smaller voltage to the scalp than icP1a, shows a more robust effect for the face-minus-house contrast starting prior to 100 ms following stimulus onset. Further, the effect expressed by icP1 b takes the form of a larger negative projection to medial occipital sites for houses over faces partially canceling the larger projection of icP1a, thereby enhancing the face positivity at this time. These findings have three main implications for ERP research on face processing: First, the ICs that constitute the face-minus-house P100 effect are independent from the ICs that constitute the N170 effect. This suggests that the P100 effect and the N170 effect are anatomically independent. Second, the timing of the N170 effect can be recovered from scalp ERPs that have spatio-temporally overlapping effects possibly associated with low-level stimulus characteristics. This unmixing of the EEG signals may reduce the need for highly constrained stimulus sets, a characteristic that is not always desirable for a topic that is highly coupled to ecological validity. Third, by unmixing the constituent processes of the EEG signals new analysis strategies are made available. In particular the exploration of the relationship between cortical processes over the period of the P100 and N170 ERP complex (and beyond) may provide previously unaccessible answers to questions such as: Is the face effect a special relationship between low-level and high-level processes along the visual stream?

Blocking Top-down awareness of Kanizsa Figures: An ERP Investigation into Bottom-up Processing of Illusory Contours

Neural models of the processing of illusory contour (ICs) diverge from one another in terms of their emphasis on bottom-up versus top-down constituents. The current study uses a dichoptic fusion paradigm to block top-down awareness of ICs in order to examine possible bottom-up effects. Group results indicate that the N170 ERP component is particularly sensitive to ICs at central occipital sites when top-down awareness of the stimulus is permitted. Furthermore, single-subject statistics reveal that the IC N170 ERP effect is highly variable across individuals in terms of timing and topographical spread. The results suggest that the ubiquitous N170 effect to ICs found in the literature depends, at least in part, on participants’ awareness of the stimulus. Therefore a strong bottom-up model of IC processing at the time of the N170 is unlikely.

Caractérisation électro-clinique des convulsions fébriles et risque d’épilepsie

Environ 2-3% d’enfants avec convulsions fébriles (CF) développent une épilepsie, mais les outils cliniques existants ne permettent pas d’identifier les enfants susceptibles de développer une épilepsie post-convulsion fébrile. Des études ont mis en évidence des anomalies d’EEG quantifiée, et plus particulièrement en réponse à la stimulation lumineuse intermittente (SLI), chez des patients épileptiques. Aucune étude n’a analysé ces paramètres chez l’enfant avec CF et il importe de déterminer s’ils sont utiles pour évaluer le pronostic des CF. Les objectifs de ce programme de recherche étaient d’identifier, d’une part, des facteurs de risque cliniques qui déterminent le développement de l’épilepsie après des CF et, d’autre part, des marqueurs électrophysiologiques quantitatifs qui différencieraient les enfants avec CF des témoins et pourraient aider à évaluer leur pronostic. Afin de répondre à notre premier objectif, nous avons analysé les dossiers de 482 enfants avec CF, âgés de 3 mois à 6 ans. En utilisant des statistiques de survie, nous avons décrit les facteurs de risque pour développer une épilepsie partielle (antécédents prénataux, retard de développement, CF prolongées et focales) et généralisée (antécédents familiaux d’épilepsie, CF récurrentes et après l’âge de 4 ans). De plus, nous avons identifié trois phénotypes cliniques distincts ayant un pronostic différent : (i) CF simples avec des antécédents familiaux de CF et sans risque d’épilepsie ultérieure; (ii) CF récurrentes avec des antécédents familiaux d’épilepsie et un risque d’épilepsie généralisée; (iii) CF focales avec des antécédents familiaux d’épilepsie et un risque d’épilepsie partielle. Afin de répondre à notre deuxième objectif, nous avons d’abord analysé les potentiels visuels steady-state (PEVSS) évoqués par la SLI (5, 7,5, 10 et 12,5 Hz) en fonction de l’âge. Le tracé EEG de haute densité (128 canaux) a été enregistré chez 61 enfants âgés entre 6 mois et 16 ans et 8 adultes normaux. Nous rapportons un développement topographique différent de l’alignement de phase des composantes des PEVSS de basses (5-15 Hz) et de hautes (30-50 Hz) fréquences. Ainsi, l’alignement de phase des composantes de basses fréquences augmente en fonction de l’âge seulement au niveau des régions occipitale et frontale. Par contre, les composantes de hautes fréquences augmentent au niveau de toutes les régions cérébrales. Puis, en utilisant cette même méthodologie, nous avons investigué si les enfants avec CF présentent des anomalies des composantes gamma (50-100 Hz) des PEVSS auprès de 12 cas de CF, 5 frères et sœurs des enfants avec CF et 15 témoins entre 6 mois et 3 ans. Nous montrons une augmentation de la magnitude et de l’alignement de phase des composantes gamma des PEVSS chez les enfants avec CF comparés au groupe témoin et à la fratrie. Ces travaux ont permis d’identifier des phénotypes électro-cliniques d’intérêt qui différencient les enfants avec CF des enfants témoins et de leur fratrie. L’étape suivante sera de vérifier s’il y a une association entre les anomalies retrouvées, la présentation clinique et le pronostic des CF. Cela pourrait éventuellement aider à identifier les enfants à haut risque de développer une épilepsie et permettre l’institution d’un traitement neuroprotecteur précoce.