Recent findings suggest, that perception of acoustic stimuli in the mouse auditory cortex relies on categorization of object-based representations. Local neuronal populations in L2/3 of the mouse auditory cortex reportedly exhibit a limited number (1-3) of stable modes of response, each possibly evoked by multiple complex sounds of variable acoustic features. Stimulation using linear intensity mixing of sounds evoking different response modes revealed an attractor-like dynamic of the underlying representation. These modes of response were hypothesized to represent the neural correlate of perceptual categorization. We have developed an experimental protocol enabling chronic two-photon imaging of the previously described population coding under awake conditions. Using this protocol we acquired data suggesting that the pattern of population activity underlying a mode of response, is stable during a week-long timeframe. We have also recorded the neural activity of a local subpopulation of somatostatin-positive inhibitory interneurons (SST+ INs) during abrupt changes in cortical representation. Our preliminary results suggest that local SST+ INs exhibit maximal firing when the neural correlate of a mode of response is exhibited by the surrounding population of principal cells. In addition, we observed a...

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Expectations substantially influence perception, but the neural mechanisms underlying this influence are not fully understood. A prominent view is that sensory neurons encode prediction error with respect to expectations on upcoming sensory input. Although the encoding of prediction error has been previously demonstrated in the human auditory cortex (AC), previous studies often induced expectations using stimulus repetition, potentially confounding prediction error with neural habituation. These studies also measured AC as a single population, failing to consider possible predictive specializations of different AC fields. Moreover, the few studies that considered prediction error to stimuli other than pure tones yielded conflicting results. Here, we used functional magnetic resonance imaging (fMRI) to systematically investigate prediction error to subjective expectations in auditory cortical fields Te1.0, Te1.1, Te1.2, and Te3, and two types of stimuli: pure tones and frequency modulated (FM) sweeps. Our results show that prediction error is elicited with respect to the participants’ expectations independently of stimulus repetition and similarly expressed across auditory fields. Moreover, despite the radically different strategies underlying the decoding of pure tones and FM-sweeps, both stimulus modalities were encoded as prediction error in most fields of AC. Altogether, our results provide unequivocal evidence that predictive coding is the general encoding mechanism in AC.

Introdução: Indivíduos com Transtorno do Espectro do Autismo (TEA) apresentam prejuízos nas interações sociais, comunicação e comportamento, além de poderem apresentar alterações cognitivas e de linguagem. Tendo em vista que o desenvolvimento da linguagem depende do funcionamento adequado da via auditiva periférica e central, ressalta-se a importância da avaliação audiológica completa, em especial, da avaliação do Sistema Nervoso Auditivo Central nessa população, tanto no diagnóstico como durante o processo terapêutico. Objetivos: caracterizar o Potencial Evocado Auditivo de Tronco Encefálico (PEATE) com estímulos clique e fala e o Potencial Evocado Auditivo de Longa Latência (PEALL) com estímulos tone burst e de fala, em indivíduos com TEA. Metodologia: participaram deste estudo 30 indivíduos na faixa etária de sete a 12 anos, de ambos os sexos, sendo 15 do grupo estudo (GE - crianças com diagnóstico de TEA) e 15 do grupo controle (GC - crianças com desenvolvimento típico - DT), pareados por sexo e idade. Foram realizados os seguintes procedimentos: anamnese, meatoscopia, avaliação audiológica básica (audiometria tonal, logoaudiometria e imitanciometria), e avaliação eletrofisiológica da audição (PEATE com estímulos clique e fala, e PEALL com estímulos tone burst e fala). Todos os exames foram realizados no Centro de Docência e Pesquisa do Departamento de Fisioterapia, Fonoaudiologia e Terapia Ocupacional da Faculdade de Medicina da Universidade de São Paulo. Resultados: No PEATE com estímulo clique, o valor médio de latência da onda I apresentou-se maior para orelha direita em ambos os grupos (valor-p = 0,037), ocorrendo assim o efeito orelha. Observou-se, também, que o interpico III - V no grupo com TEA foi maior do que o obtido no grupo com DT (valor-p = 0,046). No PEATE com estímulo de fala, a latência absoluta da onda V foi menor no grupo com TEA quando comparado ao grupo com DT (valor-p = 0,011). No PEALL, tanto para o estímulo tone burst quanto para o estímulo de fala, a latência do componente N1 foi maior na orelha direita (valor-p = 0,050), não sendo observada diferença significante entre os grupos tanto para os valores de latência quanto para os de amplitude dos componentes estudados. Conclusão: No que diz respeito ao PEATE clique, indivíduos com TEA apresentaram resultados sugestivos de alteração na via auditiva em tronco encefálico alto, indicando possíveis lesões ou disfunções do Sistema Nervoso Auditivo Central (SNAC). Com relação ao PEATE com estímulo de fala, pode-se concluir que a população de estudo apresentou codificação neural mais rápida da parte inicial do estímulo acústico (onset) quando comparada ao grupo com DT. Os resultados do PEALL não demonstraram alteração a nível cortical em indivíduos com TEA. Frente aos resultados obtidos, sugere-se novos estudos que realizem os exames eletrofisiológicos de curta e longa latência com um número maior de participantes / Introduction: Individuals with Autism Spectrum Disorder (ASD), showed issues in social interactions, communication and behavior, and it is also possible to present impaired cognitive and language skills. Taking into account the knowledge about the peripheral and central hearing, it highlights importance of the complete audiological evaluation, in particular, the evaluation of the Central Auditory Nervous System in this population, in diagnosis and during the therapeutic process. Aim: To characterize Brainstem Evoked Response Auditory (BERA) with click and speech stimuli and Long-Latency Auditory Evoked Potential (LLAEP) with tone burst and speech stimuli, in individuals with ASD. Methods: 30 children aged between seven and 12 years, of both sexes participated in this study, 15 of the study group (SG - children diagnosed with ASD) and 15 of the control group (CG - children with typical development - TD), matched by sex and age. The following tests were accomplished: anamnesis, meatoscopy, basic audiological evaluation (tonal audiometry, logoaudiometry and imitanciometry), and electrophysiological evaluation of hearing (BERA with click and speech stimulus and LLAEP with tone burst and speech stimulus). All the exams were done at the Teaching and Research Center of the Department of Physical Therapy, Speech and Hearing Therapy and Occupational Therapy, Faculty of Medicine, University of São Paulo. Results: In BERA with click stimulus, the average latency value of the wave I was higher for the right ear in all groups (p-value = 0.037), this occurring the ear effect. It was also observed that the III-V interpeak is higher in the TEA group than TD group (p-value = 0.046). In BERA with speech stimulus, an absolute latency of wave V was smaller than the ASD group when compared to the group with TD (p-value = 0.011). In the LLAEP, for the tone burst stimulus as well as for the speech stimulus, the latency of the N1 component was higher in the right ear (p-value = 0.050), between the groups were not being observed meaning differences for the latency values as for the amplitude values of the studied components. Conclusion: In relation to the BERA click, TEA group presented suggestive results of impairment in the auditory pathway, upper brainstem part, indicating possible lesions or dysfunctions of the Central Auditory Nervous System (CANS). With regard to BERA speech, can be concluded that the study population presented faster neural encoding of the initial part in the acoustic stimulus (onset) when compared with the TD group. The results of the LLAEP didn\'t show any changes in a cortical level of TEA group. From the results, we suggest new studies with BERA and LLAEP with a larger number of participants

Depuis quelques années, l’étude du code neuronal impliqué dans la perception des signaux de communication acoustique est devenue un domaine de recherche considérable. La littérature récente de ce domaine suggère que la discrimination entre ces signaux reposerait plutôt sur une organisation des décharges neuronales en motifs temporels que sur des variations globales de taux de décharge. Ma thèse a eu pour objectif de déterminer dans quelle mesure une régulation des inhibitions corticales peut (i) changer les motifs temporels déclenchés par des vocalisations conspécifiques et hétérospécifiques et (ii) modifier l’information portée par ces motifs sur l’identité des vocalisations. Nous avons enregistré l’activité neuronale dans le cortex auditif de cobayes anesthésiés en 16 sites corticaux lors de la présentation d’un jeu de vocalisations, et avons partiellement bloqué les inhibitions corticales par des applications de Gabazine (4minutes, 10µm). Dans ces conditions, les réponses évoquées sont plus fortes et les motifs temporels plus marqués. L’information mutuelle quantifiée au niveau de chaque site cortical est augmentée mais l’information populationnelle au niveau de l’ensemble des 16 sites enregistrés n’est pas modifiée, un effet qui peut s’expliquer par le fait que la redondance entre les sites corticaux est augmentée. Nous avons ensuite évalué dans quelle mesure une modulation noradrénergique était susceptible de mimer les effets d’un blocage partiel des inhibitions. Bien que les agonistes utilisés (α1, α2 et ) aient tous induit des modifications des réponses évoquées et de la reproductibilité des motifs temporels, aucun d’entre eux n’a induit de changements importants de l’information portée par les réponses neuronales aux vocalisations. En revanche, les effets induits par la phenylephrine, un agoniste α1, sont vraisemblablement sous-tendus par une action sur les inhibitions intra-corticales, ce qui rend plausible l’hypothèse d’une modulation noradrénergique des inhibitions corticales. Il est donc envisageable que l’action coordonnée de plusieurs systèmes neuromodulateurs puisse moduler les inhibitions corticales et ainsi changer la quantité d’information portée par les neurones corticaux sur l’identité des stimuli à discriminer. / Over the last 10 years, the neural code involved in the perception of acoustic communication signals has become a large area of researches. The recent literature suggests that the discrimination between these signals relies more on the temporal organization of neuronal discharges rather than on global changes of firing rate. My PhD thesis aimed at determining to what extent the regulation of cortical inhibition may (i) change the temporal patterns triggered by conspecific and heterospecific vocalizations and (ii) modify the information carried by these patterns on the vocalization identity. Neuronal activity was recorded in the auditory cortex of anesthetized guinea pigs in 16 cortical sites during presentation of a set of vocalizations, and a partial blockage of intra-cortical inhibition was performed by Gabazine application (4 minutes, 10μm). Under these conditions, evoked responses were stronger and the temporal patterns were reinforced. Mutual information quantified at each cortical site was increased but the information computed at the populationnal level did not change, an effect that could be explained by the fact that the redundancy between cortical sites was increased. We then assessed to which extent the noradrenergic modulation can mimic the effects of a partial blockage of inhibitions. Although all the tested drugs modulated both the evoked responses and the spike-timing reliability, none of the noradrenergic agonists used here (α1, α2 and ) induced significant changes in the information carried by neuronal responses. However, the effects induced by phenylephrine, an α1 agonist, seemed to involve an action on the intra-cortical inhibition, which suggests that a noradrenergic modulation of cortical inhibition can operate in the auditory cortex. It is therefore possible to envision that the coordinated action of several neuromodulatory systems modulates cortical inhibition and thus changes the information carried by cortical neurons on the stimuli identity.

Cette thèse concerne l’anatomie macroscopique des gyri de Heschl (GH) en relation avec la Préférence Manuelle (PM) et la Spécialisation Hémisphérique (SH) pour le langage étudiée dans une base de données multimodale dédiée à l’étude de la SH (la BIL&GIN), équilibrée pour le sexe et la PM. Le GH, situé à la surface du lobe temporal, abrite l’aire auditive primaire. Des études ont montré que le volume du GH est asymétrique gauche, et que le GH gauche (GHG) covarie avec les performances phonologiques et avec la quantité de cortex dévolu au traitement temporel des sons, suggérant une relation entre GHG et SH pour le langage. Pourtant l’anatomie des GH, très variable en terme de gyrification, est mal connue. Nous avons : 1- Décrit la distribution inter-hémisphérique de la gyrification des GH sur les images IRM anatomiques de 430 sujets. 2- Etudié les variations de surface et d’asymétrie du premier gyrus ou GH antérieur (GHa), montré sa diminution en présence de duplication et l’existence d’une asymétrie gauche pour les configurations les plus fréquentes avec GHG unique. Les gauchers présentaient moins de duplications droites et une perte de l’asymétrie gauche de GHa. 3- Testé si la variance de l’anatomie du GH expliquait la variabilité interindividuelle des asymétries mesurées en IRM fonctionnel pendant une tâche d’écoute de mots chez 281 sujets, et si les différences anatomiques liées à la PM étaient en relation avec une diminution de la SH pour le langage des gauchers. La distribution du nombre de GH expliquait 11% de la variance de l’asymétrie fonctionnelle du GH, les configurations à GHG unique étant les plus asymétriques gauches, sans effet de la PM sur la latéralisation fonctionnelle du GH. / This thesis concerns the macroscopical anatomy of Heschl’s gyri (HG) in relation with Manual Preference (MP) and the Hemispheric Specialization (HS) for language studied in a multimodal database dedicated to the investigation of HS and balanced for sex and MP (BIL&GIN). HG, located on the surface of the temporal lobe, hosts the primary auditory cortex. Previous studies have shown that HG volume is leftward asymmetrical and that the left HG (LHG) covaries with phonological performance and with the amount of cortex dedicated to the processing of the temporal aspects of sounds, suggesting a relationship between LHG and HSL. However HG anatomy is highly variable and little known. In this thesis we have: 1- Described HG inter-hemispheric gyrification pattern on the anatomical MRI images of 430 healthy participants. 2- Studied the variation of the first or anterior HG (aHG) surface area and its asymmetry and shown its reduction in the presence of duplication and that its leftward asymmetry was present only in the case of a single LHG. Left-handers exhibited a lower incidence of right duplication and a loss of aHG leftward asymmetry. 3- Tested whether the variance of HG anatomy explained the interindividual variability of asymmetries measured with fMRI during the listening of a list of words in 281 participants, and whether differences in HG anatomy with MP were related to decreased HS for language in left-handers. HG inter-hemispheric gyrification pattern explained 11% of the variance of HG functional asymmetry, the patterns including a unique LHG being those with the strongest leftward asymmetry. There was no incidence of MP on HG functional lateralization.

Introdução: Apesar do grande impacto da ressonância magnética funcional em neurociências, a sua aplicabilidade clínica ainda é pequena. Um dos principais motivos é a falta de dados populacionais para dar suporte à decisão clínica. Esta tese teve por objetivo formar um banco de dados normais, representativo de pacientes do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP). Métodos: Foram estudados 64 acompanhantes normais dos pacientes do HCFMUSP. Cada indivíduo realizou tarefas quem envolviam função de linguagem, somatossensorial, motor, audiovisual e de memória em aparelho de 1,5 T. Foram colhidos dados demográficos, de desempenho e neuropsicológicos dos sujeitos e de controle de qualidade do magneto de RM. As imagens funcionais foram analisadas através do software XBAM para cada indivíduo, para os grupos e para análise de correlação comportamental. Resultados: A amostra teve uma distribução demográfica variada. Os resultados das análises de grupo mostraram padrões de acordo com a literatura. O paradigma motor mostrou efeito BOLD positivo nos giros pré e pós-centrais estendendo-se para regiões pré-motoras e parietais, área motora suplementar, áreas somatosensoriais secundárias, núcleos da base e tálamo contralaterais à mão avaliada e hemisférios cerebelares ipsilaterais. O paradigma somatossensorial das mãos demonstrou efeito BOLD positivo nos giros pré e pós-centrais, núcleos da base e tálamos contralaterais à mão estimulada, cerebelo ipsilateral à mão estimulada e o córtex somatossensorial secundário bilateralmente e o da face mostrou os giros pré e pós-centrais, o córtex parietal, regiões pré-motoras, regiões temporais posteriores e inferiores e área somatosensorial secundária bilateralmente. A análise de grupo dos paradigmas de linguagem mostrou efeito BOLD positivo no giro frontal inferior e ínsula bilateralmente, maiores à esquerda, giro frontal médio esquerdo, cíngulo anterior, área motora suplementar, cerebelo à direita e vermis cerebelar, núcleos da base e tálamos à esquerda e em particular na fluência verbal falada com apresentação de letras diferentes, lobo parietal esquerdo. No paradigma audiovisual a condição visual mostrou efeito BOLD positivo no córtex occipital, parietal e cerebelo bilateralmente e a condição auditiva, nos lobos temporais bilaterais, com extensão fronto-parietal à esquerda. A análise de grupo do paradigma memória mostrou áreas no cerebelo, córtex occipital, giro frontal médio, região frontal mesial anterior e lobo parietal, com predomínio à direita. Nos mapas individuais foram detectadas muitas regiões em cada paradigma e houve grande variabilidade, sendo as regiões cerebrais que apresentaram efeito BOLD positivo com maior frequência ( 85%): giro pré-central esquerdo (95%) e cerebelo superior direito (87%) no movimento da mão direita; giro pré-central direito (88%) no movimento da mão esquerda; giro pós-central esquerdo (88%) no estímulo somatosensorial da mão direita; giro pós-central direito (89%) no estímulo somatosensorial da mão esquerda; giro lingual direito (90%) e esquerdo (88%) no estímulo visual; e giro temporal médio direito (93%) e esquerdo (91%) na condição auditiva. As tarefas de memória e fluência verbal não tiveram nenhuma região com frequência acima de 80%. Conclusões: Os padrões de ativação cerebral obtidos nas imagens de RMf do grupo de participantes são semelhantes à literatura. A freqüência das regiões com efeito BOLD positivo foi maior nos córtices primários sensoriais e motores. As informações colhidas no trabalho constituem uma base de dados que pode ser utilizada para suporte à decisão clínica. / Introduction: Functional magnetic resonance imaging has had a great impact on neuroscience, but its clinical applicability is still small. One of the main reasons is the lack of populational databases to support clinical decision. The aim of this work was to constitute a local normal database, representative of the patients from the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Methods: The sample included 64 normal subjects who, at some point, accompanied patients from the HCFMUSP. They all performed motor, somatosensory, language, audiovisual and memory paradigms in a 1,5 T magnet. Demographic, neuropsychological and behavioral data were collected. Scanner quality control was also verified. Data was analyzed through XBAM software on individual and group basis, and for behavioral correlation. Results: The sample had a variable demographic distribution. Group analysis showed results in agreement with the literature. The motor paradigm elicited positive BOLD effect in the pre and postcentral gyri, extending to premotor and parietal regions, supplementary motor area, secondary somatosensory areas, basal ganglia and thalamus contralateral to the hand in question, and ipsilateral cerebellum. Group analysis of the hand somatosensory paradigm showed pre and postcentral gyri, basal ganglia and thalamus contralateral to the stimulated hand, ipsilateral cerebellum and bilateral secondary somatosensory areas. The group analysis of the somatosensory paradigm of the face showed pre and postcentral gyri, parietal cortex, premotor areas, inferior-posterior temporal cortex and secondary somatosensory areas bilaterally. Language paradigms showed positive BOLD effect in the inferior frontal gyrus and insula bilaterally, bigger on the left, left middle frontal gyrus, anterior cingulate, supplementary motor area, right cerebellum, cerebellar vermis, left basal ganglia and thalamus, and in particular, overt verbal fluency with presentation of different letters also showed the left parietal lobe. The audiovisual paradigm group analysis showed positive BOLD effect in the occipital and parietal cortex and cerebellum bilaterally during the visual condition, and bilateral temporal with left frontal and parietal extension during the auditory condition. Finally, working memory task showed activation in the occipital cortex, cerebellum, middle frontal gyri, parietal association cortex and mesial frontal region bilaterally, with right predominance. On individual basis we detected a multitude of brain areas in each paradigm with great variability, and those with the higher frequency ( 85%) were: left precentral gyrus (95%) and superior right cerebellum (87%) during the right hand movement; right precentral gyrus (88%) during the left hand movement; left postcentral gyrus (88%) for the somatosensory stimulus of the right hand; right postcentral gyrus (89%) for the somatosensory stimulus of the left hand; right (90%) and left (88%) lingual gyri during the visual stimulus; and right (93%) and left (91%) middle temporal gyrus for the auditory stimulus. Working memory and verbal fluency had no region with a frequency above 80%. Conclusions: The patterns of cerebral activations obtained in group analysis are in agreement with the literature. Individual analysis showed a higher frequency of positive BOLD effect in the primary and sensory cortices. The data collected during this work constitute a database that can be used to support clinical decision.

S'ha investigat molt tant els mecanismes neuronals bàsics de l'audició com l'organització psicològica de la percepció de la parla. Tanmateix, en ambdós temes n'hi ha una relativa escassetat en quant a modelització. Aquí describim dos treballs de modelització. Un d'ells proposa un nou mecanisme de millora de selectivitat de freqüències que explica resultats de experiments neurofisiològics investigant manifestacions de forward masking y sobretot auditory streaming en l'escorça auditiva principal (A1). El mecanisme funciona en una xarxa feed-forward amb depressió sináptica entre el tàlem y l'escorça, però mostrem que és robust a l'introducció d'una organització realista del circuit de A1, que per la seva banda explica cantitat de dades neurofisiològics. L'altre treball descriu un mecanisme candidat d'explicar la trobada en estudis psicofísics de diferències en la percepció de paraules entre bilinguës primerencs y simultànis. Simulant tasques de decisió lèxica y discriminació de fonemes, fortifiquem l'hipòtesi de que persones sovint exposades a variacions dialectals de paraules poden guardar aquestes en el seu lèxic, sense alterar representacions fonemàtiques . / Though much experimental research exists on both basic neural mechanisms of hearing and the psychological organization of language perception, there is a relative paucity of modelling work on these subjects. Here we describe two modelling efforts. One proposes a novel mechanism of frequency selectivity improvement that accounts for results of neurophysiological experiments investigating manifestations of forward masking and above all auditory streaming in the primary auditory cortex (A1). The mechanism works in a feed-forward network with depressing thalamocortical synapses, but is further showed to be robust to a realistic organization of the neural circuitry in A1, which accounts for a wealth of neurophysiological data. The other effort describes a candidate mechanism for explaining differences in word/non-word perception between early and simultaneous bilinguals found in psychophysical studies. By simulating lexical decision and phoneme discrimination tasks in an attractor neural network model, we strengthen the hypothesis that people often exposed to dialectal word variations can store these in their lexicons, without altering their phoneme representations. / Se ha investigado mucho tanto los mecanismos neuronales básicos de la audición como la organización psicológica de la percepción del habla. Sin embargo, en ambos temas hay una relativa escasez en cuanto a modelización. Aquí describimos dos trabajos de modelización. Uno propone un nuevo mecanismo de mejora de selectividad de frecuencias que explica resultados de experimentos neurofisiológicos investigando manifestaciones de forward masking y sobre todo auditory streaming en la corteza auditiva principal (A1). El mecanismo funciona en una red feed-forward con depresión sináptica entre el tálamo y la corteza, pero mostramos que es robusto a la introducción de una organización realista del circuito de A1, que a su vez explica cantidad de datos neurofisiológicos. El otro trabajo describe un mecanismo candidato de explicar el hallazgo en estudios psicofísicos de diferencias en la percepción de palabras entre bilinguës tempranos y simultáneos. Simulando tareas de decisión léxica y discriminación de fonemas, fortalecemos la hipótesis de que personas expuestas a menudo a variaciones dialectales de palabras pueden guardar éstas en su léxico, sin alterar representaciones fonémicas.

Introdução: Apesar do grande impacto da ressonância magnética funcional em neurociências, a sua aplicabilidade clínica ainda é pequena. Um dos principais motivos é a falta de dados populacionais para dar suporte à decisão clínica. Esta tese teve por objetivo formar um banco de dados normais, representativo de pacientes do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP). Métodos: Foram estudados 64 acompanhantes normais dos pacientes do HCFMUSP. Cada indivíduo realizou tarefas quem envolviam função de linguagem, somatossensorial, motor, audiovisual e de memória em aparelho de 1,5 T. Foram colhidos dados demográficos, de desempenho e neuropsicológicos dos sujeitos e de controle de qualidade do magneto de RM. As imagens funcionais foram analisadas através do software XBAM para cada indivíduo, para os grupos e para análise de correlação comportamental. Resultados: A amostra teve uma distribução demográfica variada. Os resultados das análises de grupo mostraram padrões de acordo com a literatura. O paradigma motor mostrou efeito BOLD positivo nos giros pré e pós-centrais estendendo-se para regiões pré-motoras e parietais, área motora suplementar, áreas somatosensoriais secundárias, núcleos da base e tálamo contralaterais à mão avaliada e hemisférios cerebelares ipsilaterais. O paradigma somatossensorial das mãos demonstrou efeito BOLD positivo nos giros pré e pós-centrais, núcleos da base e tálamos contralaterais à mão estimulada, cerebelo ipsilateral à mão estimulada e o córtex somatossensorial secundário bilateralmente e o da face mostrou os giros pré e pós-centrais, o córtex parietal, regiões pré-motoras, regiões temporais posteriores e inferiores e área somatosensorial secundária bilateralmente. A análise de grupo dos paradigmas de linguagem mostrou efeito BOLD positivo no giro frontal inferior e ínsula bilateralmente, maiores à esquerda, giro frontal médio esquerdo, cíngulo anterior, área motora suplementar, cerebelo à direita e vermis cerebelar, núcleos da base e tálamos à esquerda e em particular na fluência verbal falada com apresentação de letras diferentes, lobo parietal esquerdo. No paradigma audiovisual a condição visual mostrou efeito BOLD positivo no córtex occipital, parietal e cerebelo bilateralmente e a condição auditiva, nos lobos temporais bilaterais, com extensão fronto-parietal à esquerda. A análise de grupo do paradigma memória mostrou áreas no cerebelo, córtex occipital, giro frontal médio, região frontal mesial anterior e lobo parietal, com predomínio à direita. Nos mapas individuais foram detectadas muitas regiões em cada paradigma e houve grande variabilidade, sendo as regiões cerebrais que apresentaram efeito BOLD positivo com maior frequência ( 85%): giro pré-central esquerdo (95%) e cerebelo superior direito (87%) no movimento da mão direita; giro pré-central direito (88%) no movimento da mão esquerda; giro pós-central esquerdo (88%) no estímulo somatosensorial da mão direita; giro pós-central direito (89%) no estímulo somatosensorial da mão esquerda; giro lingual direito (90%) e esquerdo (88%) no estímulo visual; e giro temporal médio direito (93%) e esquerdo (91%) na condição auditiva. As tarefas de memória e fluência verbal não tiveram nenhuma região com frequência acima de 80%. Conclusões: Os padrões de ativação cerebral obtidos nas imagens de RMf do grupo de participantes são semelhantes à literatura. A freqüência das regiões com efeito BOLD positivo foi maior nos córtices primários sensoriais e motores. As informações colhidas no trabalho constituem uma base de dados que pode ser utilizada para suporte à decisão clínica. / Introduction: Functional magnetic resonance imaging has had a great impact on neuroscience, but its clinical applicability is still small. One of the main reasons is the lack of populational databases to support clinical decision. The aim of this work was to constitute a local normal database, representative of the patients from the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Methods: The sample included 64 normal subjects who, at some point, accompanied patients from the HCFMUSP. They all performed motor, somatosensory, language, audiovisual and memory paradigms in a 1,5 T magnet. Demographic, neuropsychological and behavioral data were collected. Scanner quality control was also verified. Data was analyzed through XBAM software on individual and group basis, and for behavioral correlation. Results: The sample had a variable demographic distribution. Group analysis showed results in agreement with the literature. The motor paradigm elicited positive BOLD effect in the pre and postcentral gyri, extending to premotor and parietal regions, supplementary motor area, secondary somatosensory areas, basal ganglia and thalamus contralateral to the hand in question, and ipsilateral cerebellum. Group analysis of the hand somatosensory paradigm showed pre and postcentral gyri, basal ganglia and thalamus contralateral to the stimulated hand, ipsilateral cerebellum and bilateral secondary somatosensory areas. The group analysis of the somatosensory paradigm of the face showed pre and postcentral gyri, parietal cortex, premotor areas, inferior-posterior temporal cortex and secondary somatosensory areas bilaterally. Language paradigms showed positive BOLD effect in the inferior frontal gyrus and insula bilaterally, bigger on the left, left middle frontal gyrus, anterior cingulate, supplementary motor area, right cerebellum, cerebellar vermis, left basal ganglia and thalamus, and in particular, overt verbal fluency with presentation of different letters also showed the left parietal lobe. The audiovisual paradigm group analysis showed positive BOLD effect in the occipital and parietal cortex and cerebellum bilaterally during the visual condition, and bilateral temporal with left frontal and parietal extension during the auditory condition. Finally, working memory task showed activation in the occipital cortex, cerebellum, middle frontal gyri, parietal association cortex and mesial frontal region bilaterally, with right predominance. On individual basis we detected a multitude of brain areas in each paradigm with great variability, and those with the higher frequency ( 85%) were: left precentral gyrus (95%) and superior right cerebellum (87%) during the right hand movement; right precentral gyrus (88%) during the left hand movement; left postcentral gyrus (88%) for the somatosensory stimulus of the right hand; right postcentral gyrus (89%) for the somatosensory stimulus of the left hand; right (90%) and left (88%) lingual gyri during the visual stimulus; and right (93%) and left (91%) middle temporal gyrus for the auditory stimulus. Working memory and verbal fluency had no region with a frequency above 80%. Conclusions: The patterns of cerebral activations obtained in group analysis are in agreement with the literature. Individual analysis showed a higher frequency of positive BOLD effect in the primary and sensory cortices. The data collected during this work constitute a database that can be used to support clinical decision.

Introdução: Indivíduos com Transtorno do Espectro do Autismo (TEA) apresentam prejuízos nas interações sociais, comunicação e comportamento, além de poderem apresentar alterações cognitivas e de linguagem. Tendo em vista que o desenvolvimento da linguagem depende do funcionamento adequado da via auditiva periférica e central, ressalta-se a importância da avaliação audiológica completa, em especial, da avaliação do Sistema Nervoso Auditivo Central nessa população, tanto no diagnóstico como durante o processo terapêutico. Objetivos: caracterizar o Potencial Evocado Auditivo de Tronco Encefálico (PEATE) com estímulos clique e fala e o Potencial Evocado Auditivo de Longa Latência (PEALL) com estímulos tone burst e de fala, em indivíduos com TEA. Metodologia: participaram deste estudo 30 indivíduos na faixa etária de sete a 12 anos, de ambos os sexos, sendo 15 do grupo estudo (GE - crianças com diagnóstico de TEA) e 15 do grupo controle (GC - crianças com desenvolvimento típico - DT), pareados por sexo e idade. Foram realizados os seguintes procedimentos: anamnese, meatoscopia, avaliação audiológica básica (audiometria tonal, logoaudiometria e imitanciometria), e avaliação eletrofisiológica da audição (PEATE com estímulos clique e fala, e PEALL com estímulos tone burst e fala). Todos os exames foram realizados no Centro de Docência e Pesquisa do Departamento de Fisioterapia, Fonoaudiologia e Terapia Ocupacional da Faculdade de Medicina da Universidade de São Paulo. Resultados: No PEATE com estímulo clique, o valor médio de latência da onda I apresentou-se maior para orelha direita em ambos os grupos (valor-p = 0,037), ocorrendo assim o efeito orelha. Observou-se, também, que o interpico III - V no grupo com TEA foi maior do que o obtido no grupo com DT (valor-p = 0,046). No PEATE com estímulo de fala, a latência absoluta da onda V foi menor no grupo com TEA quando comparado ao grupo com DT (valor-p = 0,011). No PEALL, tanto para o estímulo tone burst quanto para o estímulo de fala, a latência do componente N1 foi maior na orelha direita (valor-p = 0,050), não sendo observada diferença significante entre os grupos tanto para os valores de latência quanto para os de amplitude dos componentes estudados. Conclusão: No que diz respeito ao PEATE clique, indivíduos com TEA apresentaram resultados sugestivos de alteração na via auditiva em tronco encefálico alto, indicando possíveis lesões ou disfunções do Sistema Nervoso Auditivo Central (SNAC). Com relação ao PEATE com estímulo de fala, pode-se concluir que a população de estudo apresentou codificação neural mais rápida da parte inicial do estímulo acústico (onset) quando comparada ao grupo com DT. Os resultados do PEALL não demonstraram alteração a nível cortical em indivíduos com TEA. Frente aos resultados obtidos, sugere-se novos estudos que realizem os exames eletrofisiológicos de curta e longa latência com um número maior de participantes / Introduction: Individuals with Autism Spectrum Disorder (ASD), showed issues in social interactions, communication and behavior, and it is also possible to present impaired cognitive and language skills. Taking into account the knowledge about the peripheral and central hearing, it highlights importance of the complete audiological evaluation, in particular, the evaluation of the Central Auditory Nervous System in this population, in diagnosis and during the therapeutic process. Aim: To characterize Brainstem Evoked Response Auditory (BERA) with click and speech stimuli and Long-Latency Auditory Evoked Potential (LLAEP) with tone burst and speech stimuli, in individuals with ASD. Methods: 30 children aged between seven and 12 years, of both sexes participated in this study, 15 of the study group (SG - children diagnosed with ASD) and 15 of the control group (CG - children with typical development - TD), matched by sex and age. The following tests were accomplished: anamnesis, meatoscopy, basic audiological evaluation (tonal audiometry, logoaudiometry and imitanciometry), and electrophysiological evaluation of hearing (BERA with click and speech stimulus and LLAEP with tone burst and speech stimulus). All the exams were done at the Teaching and Research Center of the Department of Physical Therapy, Speech and Hearing Therapy and Occupational Therapy, Faculty of Medicine, University of São Paulo. Results: In BERA with click stimulus, the average latency value of the wave I was higher for the right ear in all groups (p-value = 0.037), this occurring the ear effect. It was also observed that the III-V interpeak is higher in the TEA group than TD group (p-value = 0.046). In BERA with speech stimulus, an absolute latency of wave V was smaller than the ASD group when compared to the group with TD (p-value = 0.011). In the LLAEP, for the tone burst stimulus as well as for the speech stimulus, the latency of the N1 component was higher in the right ear (p-value = 0.050), between the groups were not being observed meaning differences for the latency values as for the amplitude values of the studied components. Conclusion: In relation to the BERA click, TEA group presented suggestive results of impairment in the auditory pathway, upper brainstem part, indicating possible lesions or dysfunctions of the Central Auditory Nervous System (CANS). With regard to BERA speech, can be concluded that the study population presented faster neural encoding of the initial part in the acoustic stimulus (onset) when compared with the TD group. The results of the LLAEP didn\'t show any changes in a cortical level of TEA group. From the results, we suggest new studies with BERA and LLAEP with a larger number of participants