[A comparative study of pragmatic language disorders and autism spectrum disorders using magnetoencephalography]. / Estudio comparativo mediante magnetoencefalografíade los trastornos del lenguaje pragmáticoy los trastornos del espectro autista.

INTRODUCTION: Pragmatics refers to the social use of language; its precursors are already present during the process of maturing, during the preverbal stage, and become manifest when the child starts to point and to share his or her attention with another person. In cases of specific language impairment (SLI) and autism spectrum disorders (ASD) it can be altered to varying degrees. PATIENTS AND METHODS: Due to the difficulties involved in diagnosis from a clinical point of view, we carried out a study by means of magnetoencephalography (MEG) on a series of 11 patients who had SLI and another series of 9 patients with ASD, in order to determine whether MEG is capable of distinguishing these diagnoses. RESULTS: Patients with SLI displayed pathological activity in the frontal and middle temporal regions of both hemispheres. Patients with ASD showed pathological activity in the perisylvian area. Expressive-receptive SLI with pragmatic language disorder showed pathological activity that was similar to that seen in autism. CONCLUSION: MEG can be used to distinguish between SLI and ASD by studying the epileptiform activity that occurs in pervasive developmental disorders. MEG helps us to understand the continuum that exists between SLI or expressive-receptive SLI and autism.

Estudio comparativo mediante magnetoencefalografía de los trastornos del lenguaje pragmático y los trastornos del espectro autista / A comparative study of pragmatic language disorders and autism spectrum disorders using magnetoencephalography

Introducción. La pragmática es el uso social del lenguaje;sus precursores ya están presentes durante el proceso de maduración,durante la etapa preverbal, y se manifiestan cuando el niño empiezaa señalar y a compartir su atención con otra persona. Éstapuede estar alterada en los trastornos específicos del lenguaje (TEL)y en los trastornos del espectro autista (TEA). Pacientes y métodos.Debido a las dificultades diagnósticas desde el punto de vista clínico,hemos realizado un estudio con magnetoencefalografía (MEG) auna serie de 11 pacientes que presentaban un TEL y otra serie de 9pacientes con un TEA, para comprobar si la MEG es capaz de distinguirestos diagnósticos. Resultados. Los pacientes con TEL presentanactividad patológica en las regiones frontales y temporal mediade ambos hemisferios. Los pacientes con TEA presentan actividadpatológica en la zona perisilviana. Los TEL expresivo-receptivos contrastorno pragmático del lenguaje presentan una actividad patológicaparecida al autismo. Conclusión. La MEG, mediante el estudio dela actividad epileptiforme en los trastornos generalizados del desarrollo,permite distinguir los TEL con respecto a los TEA. La MEGayuda a entender el continuo entre TEL o TEL expresivo-receptivo yautismo

Introduction. Pragmatics refers to the social use of language; its precursors are already present during the processof maturing, during the preverbal stage, and become manifest when the child starts to point and to share his or her attentionwith another person. In cases of specific language impairment (SLI) and autism spectrum disorders (ASD) it can be altered tovarying degrees. Patients and methods. Due to the difficulties involved in diagnosis from a clinical point of view, we carriedout a study by means of magnetoencephalography (MEG) on a series of 11 patients who had SLI and another series of 9patients with ASD, in order to determine whether MEG is capable of distinguishing these diagnoses. Results. Patients with SLIdisplayed pathological activity in the frontal and middle temporal regions of both hemispheres. Patients with ASD showedpathological activity in the perisylvian area. Expressive-receptive SLI with pragmatic language disorder showed pathologicalactivity that was similar to that seen in autism. Conclusion. MEG can be used to distinguish between SLI and ASD by studyingthe epileptiform activity that occurs in pervasive developmental disorders. MEG helps us to understand the continuum thatexists between SLI or expressive-receptive SLI and autism

[Frontal seizures recorded by magnetoencephalography. Case report]. / Crisis frontales registradas mediante magnetoencefalografía. Caso clínico.

INTRODUCTION: This paper reports the usefulness of magnetoencephalography (MEG) in the anatomical localization of the onset and spread of seizures. CASE REPORT: In a 34-year-old male patient who suffered from drug-resistant complex partial seizures (sometimes generalized) with loss of awareness, magnetic resonance imaging revealed a probable left frontobasal cortical dysplasia. Ictal scalp electroencephalogram showed left frontotemporal theta waves. Electrocorticography (ECoG) registered interictal polyspike discharges and located the seizure onset in the lateral orbital side of the left frontal lobe. Three seizures were registered by MEG, clinically similar to the ones usually experienced by the patient. MEG ictal spike dipole location showed seizure onset coming from the left inferior frontal gyrus (as the ECoG), spreading on to other frontal areas, insula and temporal lobe, all in the left hemisphere. CONCLUSION: MEG may be considered as a useful diagnosis modality in the study of partial seizure physiopathology as well as in its presurgical evaluation.

Crisis frontales registradas mediante magnetoencefalografía. Caso clínico / Frontal seizures recorded by magnetoencephalography. Case report

Introducción. Este artículo expone un ejemplo de la utilidadde la magnetoencefalografía (MEG) en la localización anatómicadel inicio y la propagación de las crisis epilépticas. Caso clínico.Se trata de un paciente de 34 años con crisis parciales complejas farmacorresistentes.La resonancia magnética presenta una probabledisplasia cortical frontobasal izquierda. El electroencefalograma ictalde superficie revela ondas theta frontotemporales izquierdas. Enel registro con electrodos subdurales se demuestra la existencia deanomalías epileptiformes interictales durante el sueño, entre las quepredominan las polipuntas, y crisis de inicio focal en la cara lateroorbitariadel lóbulo frontal izquierdo. La MEG registra tres crisis clínicamentesimilares a las experimentadas por el paciente y permitelocalizar el inicio de las crisis en la circunvolución frontal inferiorizquierda, con propagación a otras áreas frontales, la ínsula y ellóbulo temporal, todo ello en el hemisferio izquierdo. Conclusión. LaMEG puede considerarse como un elemento diagnóstico útil en el estudiode la fisiopatología de las crisis parciales, así como en la evaluaciónprequirúrgica

Introduction. This paper reports the usefulness of magnetoencephalography (MEG) in the anatomical localization ofthe onset and spread of seizures. Case report. In a 34-year-old male patient who suffered from drug-resistant complex partialseizures (sometimes generalized) with loss of awareness, magnetic resonance imaging revealed a probable left frontobasalcortical dysplasia. Ictal scalp electroencephalogram showed left frontotemporal theta waves. Electrocorticography (ECoG)registered interictal polyspike discharges and located the seizure onset in the lateral orbital side of the left frontal lobe. Threeseizures were registered by MEG, clinically similar to the ones usually experienced by the patient. MEG ictal spike dipolelocation showed seizure onset coming from the left inferior frontal gyrus (as the ECoG), spreading on to other frontal areas,insula and temporal lobe, all in the left hemisphere. Conclusion. MEG may be considered as a useful diagnosis modality in thestudy of partial seizure physiopathology as well as in its presurgical evaluation

Bases neurológicas del lenguaje. Aportaciones desde la magnetoencefalografía / Neurological basis of language: contributions from magnetoencephalography

Objetivo. Presentar una revisión de las aportaciones de la magnetoencefalografía al estudio de las bases cerebralesdel procesamiento del lenguaje, con especial atención a los trabajos centrados en las alteraciones que pueden sufrir. Desarrollo.La magnetoencefalografía es una técnica de neuroimagen funcional capaz de caracterizar con alta precisión espacialy temporal patrones de actividad cerebral. Estas propiedades permiten no sólo un estudio teórico de las bases neuronalesdel procesamiento verbal, sino: a) establecer un sencillo protocolo capaz de localizar las áreas receptivas del lenguaje enla corteza cerebral, con gran utilidad a la hora de proporcionar información valiosa en casos que necesitan intervención quirúrgica;b) utilizar ese mismo protocolo para estudiar la reorganización funcional del procesamiento lingüístico en diferentespatologías como la afasia o la epilepsia; y c) proporcionar información sobre las alteraciones cerebrales involucradas entrastornos evolutivos del lenguaje como la dislexia o el trastorno específico del lenguaje, en los que la existencia de disfuncionesneurológicas aún no está clara. Conclusiones. La evidencia actual apunta a que los mecanismos neurológicos involucradosen el procesamiento del lenguaje, tanto en sujetos normales como en personas con diferentes patologías, implican uncomplejo patrón espaciotemporal de actividad cerebral. En ese sentido, la magnetoencefalografía resulta una técnica fundamentala la hora de iluminar la organización neurocognitiva del lenguaje

Aim. To present a review on magnetoencephalographic contributions to the study of the neurological basis oflanguage processing and its disorders. Development. Magnetoencephalography is a functional neuroimaging technique thatallows high spatial and temporal resolution characterization of brain activity patterns. Due to these features we can afford,not just a theoretical approach to verbal processing neuronal bases, but: a) to establish a simple procedure which enables thelocalization of language receptive areas in the brain cortex, highly valuable information for surgical purposes; b) to use thissame procedure for the study of functional reorganization of linguistic processes as in aphasia or epilepsy; and c) to provideinformation regarding brain abnormalities involving language evolutive disorders, such as dyslexia and specific languageimpairment, for which a neurological dysfunctions have not yet been established. Conclusions. Current evidence suggests acomplex spatio-temporal activation pattern for the neurological mechanisms involved in language processing, for both normalsubjects and people with different language disorders. In this sense, magnetoencephalography is a relevant tool that wouldshed some light onto language neurocognitive organization

[Magnetoencephalography in cognitive disorders involving frontal lobes]. / La magnetoencefalografía en los trastornos cognitivos del lóbulo frontal.

INTRODUCTION AND DEVELOPMENT: Frontal lobe, more specifically prefrontal cortex, is one of the brain regions that undergoes more protracted ongoing development. The wider the developmental window of one brain structure, the more vulnerable the functions related to it. Hence, executive functions, which are mediated by prefrontal networks, seems to be specially vulnerable during childhood. Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent neurodevelopmental disorders. Functional neuroimaging techniques have shown a dysfunction in a fronto-striatal network in this disorder, that is likely subserving deficits in executive processes, such as in response inhibition. DISCUSSION: This review focuses on contributions of neuroimaging techniques, with high spatial (SPECT, PET and fMRI), temporal (ERP) and spatio-temporal (MEG) resolution, to the neurofunctionality of ADHD.

La magnetoencefalografía en los trastornos cognitivos del lóbulo frontal / Magnetoencephalography in cognitive disorders involving frontal lobes

Introducción y desarrollo. El lóbulo frontal, y más en concreto la corteza prefrontal, es una de las regiones cerebrales con un curso de desarrollo más prolongado. Cuanto mayor es el período de desarrollo de una estructura cerebral, mayor es la vulnerabilidad de las funciones relacionadas con ella. Por esto, las funciones ejecutivas, que están mediadas por circuitos prefrontales, parecen ser especialmente vulnerables durante la infancia. El trastorno por déficit de atención con hiperactividad (TDAH) es uno de los trastornos del neurodesarrollo con mayor prevalencia. Las técnicas de neuroimagen han mostrado la existencia de una disfunción en una red frontoestriatal en este trastorno, lo que podría estar mediando las alteraciones observadas en procesos ejecutivos como, por ejemplo, la inhibición de respuesta. Discusión. Esta revisión se centra en las contribuciones de las técnicas de neuroimagen funcional con alta resolución espacial (SPECT, PET y RMf), temporal (PRAD) y espaciotemporal (MEG), a la neurofuncionalidad del TDAH (AU)

Introduction and development. Frontal lobe, more specifically prefrontal cortex, is one of the brain regions that undergoes more protracted ongoing development. The wider the developmental window of one brain structure, the more vulnerable the functions related to it. Hence, executive functions, which are mediated by prefrontal networks, seems to be specially vulnerable during childhood. Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent neurodevelopmental disorders. Functional neuroimaging techniques have shown a dysfunction in a fronto-striatal network in this disorder, that is likely subserving deficits in executive processes, such as in response inhibition. Discussion. This review focuses on contributions of neuroimaging techniques, with high spatial (SPECT, PET and fMRI), temporal (ERP) and spatiotemporal (MEG) resolution, to the neurofunctionality of ADHD (AU)

[A magnetoencephalographic study of generalised developmental disorders. A new proposal for their classification]. / Estudio mediante magnetoencefalografia de los trastornos generalizados del desarrollo. Nueva propuesta de clasificacion.

INTRODUCTION: Autistic spectrum disorders (ASD) is a term that is not included in DSM IV or in ICD 10, which are the diagnostic tools most commonly used by clinical professionals but can offer problems in research when it comes to finding homogenous groups. DEVELOPMENT: From a neuropaediatric point of view, there is a need for a classification of the generalised disorders affecting development and for this purpose we used Wing's triad, which defines the continuum of the autistic spectrum, and the information provided by magnetoencephalography (MEG) as grouping elements. Specific generalised developmental disorders were taken as being those syndromes that partially expressed some autistic trait, but with their own personality so that they could be considered to be a specific disorder. ASD were classified as being primary, cryptogenic or secondary. The primary disorders, in turn, express a continuum that ranges from Savant syndrome to Asperger's syndrome and the different degrees of early infantile autism. MEG is a functional neuroimaging technique that has enabled us to back up this classification.

[The neurofunctional foundation of cognitive rigidity in attention deficit hyperactivity disorder: some preliminary findings]. / Sustrato neurofuncional de la rigidez cognitiva en el trastorno por deficit de atencion con hiperactividad: resultados preliminares.

INTRODUCTION: It has been proposed that there is an impairment in cognitive flexibility in children with attention deficit hyperactivity disorder (ADHD). The Wisconsin card sorting test (WCST) is the most widely used neuropsychological test for assessing this process. Previous studies have reported the presence of a subgroup of children with ADHD which has a low cognitive flexibility. In addition this subgroup showed a high resistance to the treatment with stimulant medication. OBJECTIVES: The aim of this study was to examine whether there were different patterns of brain magnetic activity in different subgroups of ADHD, during the performance of a cognitive flexibility task, such as WCST. PATIENTS AND METHODS: We recruited a sample of 18 children, divided into three groups according to DSM IV R diagnostic criteria. Here we present preliminary data based on a subsample of nine children. Brain magnetic activity was registered while the children performed the WCST by means of Magnetoencephalography (MEG). This is a non invasive neuroimaging technique with a high spatio temporal resolution. RESULTS: Preliminary results showed that ADHD mixed group had a higher rate of perseverative responses. In addition, a different pattern of brain magnetic activity was noted in this group, showing less activation in anterior cingulate cortex and dorsolateral prefrontal cortex in the left hemisphere during the first 400 ms. CONCLUSIONS: MEG seems to be an useful tool to describe the brain network that subserves cognitive flexibility in different groups of children. It could have important repercussions in the classification of ADHD, both neuropsychologically and pharmacologically.

Sustrato neurofuncional de la rigidez cognitiva en el trastorno por déficit de atención con hiperactividad: resultados preliminares / The neurofunctional foundation of cognitive rigidity in attention déficit hyperactivity disorder: Some preliminary findings

Introducción. Distintos autores han propuesto que los ni- ños con trastorno por déficit de atención con hiperactividad (TDAH) presentan una alteración en el proceso de flexibilidad cognitiva (FC). El test de clasificación de tarjetas de Wisconsin (WCST) es uno de los tests neuropsicológicos más empleado para evaluar este proceso. Estudios previos han descrito la presencia de un subgrupo de niños con TDAH que presentan una baja FC. Además, este subgrupo muestra una alta resistencia al tratamiento con fármacos estimulantes. Objetivos. El objetivo del presente estudio fue examinar si diferentes subgrupos de TDAH presentaban distintos patrones de actividad magnética cerebral durante la ejecución de una tarea de FC (WCST). Pacientes y métodos. La muestra consistió en 18 niños, divididos en tres grupos de acuerdo con los criterios diagnósticos del DSM-IV-R. En este trabajo presentamos datos preliminares basados en una submuestra de nueve niños. Se realizó un registro de la actividad magnética cerebral mientras los niños realizaban el WCST, por medio de la magnetoencefalografía (MEG). Ésta es una técnica de neuroimagen no invasiva y con una elevada resolución espaciotemporal. Resultados. Los resultados preliminares mostraron que el grupo TDAH-combinado tuvo un mayor número de respuestas perseverativas. Además, este grupo presentó un patrón diferente de actividad magnética cerebral, y mostró una menor activación en el cíngulo anterior y la corteza prefrontal dorsolateral del hemisferio izquierdo durante los primeros 400 ms. Conclusiones. La MEG parece ser una herramienta útil para describir cuál es el circuito cerebral subyacente al proceso de FC en diferentes grupos de niños. Esto podría tener importantes repercusiones en la clasificación del TDAH, tanto desde un punto de vista neuropsicológico como farmacológico (AU)

Introduction. It has been proposed that there is an impairment in cognitive flexibility in children with attention deficit hyperactivity disorder (ADHD). The Wisconsin card sorting test (WCST) is the most widely used neuropsychological test for assessing this process. Previous studies have reported the presence of a subgroup of children with ADHD which has a low cognitive flexibility. In addition this subgroup showed a high resistance to the treatment with stimulant medication. Objectives. The aim of this study was to examine whether there were different patterns of brain magnetic activity in different subgroups of ADHD, during the performance of a cognitive flexibility task, such as WCST. Patients and methods. We recruited a sample of 18 children, divided into three groups according to DSM-IV-R diagnostic criteria. Here we present preliminary data based on a subsample of nine children. Brain magnetic activity was registered while the children performed the WCST by means of magnetoencephalography (MEG). This is a non-invasive neuroimaging technique with a high spatio-temporal resolution. Results. Preliminary results showed that ADHD-mixed group had a higher rate of perseverative responses. In addition, a different pattern of brain magnetic activity was noted in this group, showing less activation in anterior cingulate cortex and dorsolateral prefrontal cortex in the left hemisphere during the first 400 ms. Conclusions. MEG seems to be an useful tool to describe the brain network that subserves cognitive flexibility in different groups of children. It could have important repercussions in the classification of ADHD, both neuropsychologically and pharmacologically (AU)

[Cognition and neural networks, a new perspective based on functional neuroimaging]. / Cognición y redes neurales, una nueva perspectiva desde la neuroimagen funcional.

AIM: We went through a critical review of the current status of neuroimaging studies of cognition. Thus, we argue why the use of a neuronal network perspective could led us to a better understanding of cognition than a localizationism perspective. METHOD: The question about how cognitive functions are organized in the brain, comes from the very early lesions studies. Electrocortical stimulation and the intracorotid amytal procedure collaborate together with lesions studies to increase the knowledge about the organization of cognitive functions in the brain. Functional neuroimaging could help to this issue answering the following questions: where, when and how the activity is produced in the brain. Many of the functional neuroimaging studies have addressed the question of where the activity is located, but very few has been concentrated into describe the spatio temporal profiles of brain activity, and then how the neural networks which support cognition are organized. Taking into account just one of this perspectives (where or when) we could achieve a reductionism view of the problem. CONCLUSIONS: Executive function, memory or language are more distributed than located in just one area, even the different subprocesses that are included in each of this functions are supported by a network rather than a particular area. We analyze the current available functional neuroimaging techniques under this view and its possibilities to describe the neural networks which support cognition.

[Neuromagnetic correlates of dyslexia]. / Correlatos neuromagnéticos de la dislexia.

Dyslexia was first described over a century ago and since then many theories have been put forward to explain it, but we still do not have one single unified theory that explains the problem. Furthermore, over the years a great deal of research work has also been carried out that relates dyslexia with disorders in different brain structures, and yet we still do not have a clear idea of exactly which neurophysiological mechanisms are involved. It has been claimed, however, that the disorder may be caused by specific deficits in the left frontotemporal region or atypical asymmetries in the left perisylvian regions. Lastly, neuroimaging techniques, such as functional magnetic resonance or mapping of the electrical activity in the brain, have helped to further studies into dyslexia over the last decade. Recently, the introduction of magnetoencephalography in the study of the brain has opened up a whole new range of possibilities that will allow most of the controversial points raised by research into dyslexia using neuroimaging techniques to be resolved empirically.

[The neuromagnetic correlates of language]. / Correlatos neuromagnéticos del lenguaje.

Studies of language using different functional neuroimaging techniques have shown the cortical structures to be involved in the functions of language, both in control subjects and in patients with different neurological pathologies who are to undergo brain surgery. Magnetoencephalography (MEG) is a totally non-invasive technique that measures the magnetic fields generated by the flow of intracellular current produced in the dendrites of the pyramidal neurones. MEG also offers the possibility of lateralizing language, so enabling us to know which areas of language lie within the dominant hemisphere and to establish the temporal patterns that reveal the organisation, either in sequence or in parallel, of the different areas that are activated. This will provide us with a deeper understanding of the physiological foundations upholding both language and other cognitive processes.

[Clinical features of epilepsy in autism spectrum disorders]. / Clínica de la epilepsia en los trastornos del espectro autista.

Autism is a rare disease, but is currently in vogue. An incidence of 1/1,000 has been estimated for early childhood autism, but in autism spectrum the incidence can reach 30/1,000. The clinical characteristics of autism are cognitive language disorders, lack of social interaction, obsessive behaviours with stereotypic movements and epilepsy. For some authors it is an associated symptom while for others it is a cardinal symptom of the disease. Epilepsy in autism, as an association, was reported as early as 1944 by Leo Kanner, in describing his initial work involving 11 cases and how one of them suffered from epilepsy. In 1960, the prevalence of epilepsy among autistic patients was evaluated and found to be much higher than in the normal population. The figures differ from author to author, but really they depend on age: the higher the age, the greater the prevalence of epilepsy. It was in fact this detail that drew our attention to this issue, and triggered the first questions in our research into autism and epilepsy. The series vary from 4 to 86%, depending on the methodology used to confirm the epilepsy. In our casuistics, between the ages of 1 and 18 years, 20% of these children with autism spectrum disorders suffer some kind of epileptic seizures, and 80% suffer what other researchers call subclinical seizures . In this paper, the symptomatology of the most important subclinical seizures that have been observed in these children is presented; the diseases associated with autism are commented on; the concept of primary and secondary autism is discussed; we explain why seizures occur in autism and their consequences as a neurodevelopmental disorder, and we put forward an interesting hypothesis within our general theory of autism. We also comment on the importance that the use of functional magnetic images in the study of autism has in our research.

[Savant or idiot savant syndrome]. / El síndrome de savant o idiot savant.

Savant syndrome is currently still very mysterious, yet, thanks to the progress made in neuroimaging studies and especially MSI (Magnetic Source Imaging) techniques, a little more is now known about it. The theory, formulated many years ago, about damage to the left hemisphere of the brain has been supported by functional neuroimaging. Its relation to developmental disorders or to autism spectrum disorders is far more justified today and can be explained on the basis of its neuropathology. We present a study based on a review of the scientific literature concerning the syndrome, from the first time it was described back in 1789 by Benjamin Rush up to the present day. We comment on its epidemiology and positive clinical manifestations, involving brilliant artistic talent and dazzling memory, but also the negative aspects suffered by these autistic patients. The most important theories are discussed together with the clinical coincidence with frontotemporal dementia and the responsibility of the right hemisphere when there are alterations in the contralateral hemisphere. The latest contributions made by Positron Emission Tomography and magnetoencephalography will be discussed and a mini-video of a personal case will be projected.

[Magnetoencephalographic study in patients with cognitive impairment]. / Estudio magnetoencefalográfico en pacientes con deterioro cognitivo.

INTRODUCTION: In early stages, dementia is a neurodegenerative process with difficult diagnosis. Although well defined clinically, its neurophysiological, neuroradiological and metabolic diagnosis is still unsuccessful. PATIENTS AND METHOD: A MEG study using a 148 channel whole head magnetometer (Magnes 2500 WH) and evaluation by mini mental state examination (MMSE) was performed in 31 subjects. Statistical analyses was made to correlate number of dipoles of slow waves and neuropsychological variables. RESULTS: The 63.3% (21 patients) show slow waves dipoles in temporal lobes (52.3% were bitemporal). Right temporal lobe has 119.5 23.3 dipoles (averaged value), and left temporal lobe has 126.2 19.8 dipoles (averaged value). The 25% (8 patients) shown slow waves dipoles in parietals lobes, 5 of them biparietal. Correlation between MMSE averaged scores and temporal lobe dipoles was r= 0.84. CONCLUSION: MEG results show that slow waves dipoles number in temporal lobes is related with low scores in the mini mental state examination. MEG could be a usefully complementary method in evaluation and following of degree of cognitive impairment in these patients

Estudio magnetoencefalográfico en pacientes con deterioro cognitivo / Magnetoencephalographic study in patients with cognitive impairment

Introducción. La demencia es un proceso neurodegenerativo de difícil diagnóstico en su fase precoz. Se ha definido bien clínicamente, aunque su diagnóstico neurofisiológico, de neuroimagen y metabólico es todavía insuficiente. Pacientes y métodos. Se realizó registro magnetoencefalográfico (equipo whole-head de 148 canales Magnes 2500 WH) y valoración mediante examen minimental en 31 sujetos. Se realizó análisis estadístico para correlacionar el número de dipolos de ondas lentas con las variables neuropsicológicas. Resultados. En el 63,3 por ciento (21 pacientes) se objetivaron durante el análisis MEG dipolos de ondas lentas en lóbulos temporales, y en un 52,3 por ciento de éstos la localización era bitemporal. La media de los dipolos en lóbulo temporal derecho fue de 119,5 ñ 23,3, y en lóbulo temporal izquierdo de 126,2 ñ 19,8. Un 25 por ciento (ocho pacientes) presentaron dipolos de ondas lentas en lóbulos parietales y en cinco de ellos la localización fue biparietal. La correlación entre las puntuaciones medias del examen minimental y los dipolos en lóbulo temporal fue r= -0,84. Conclusión. Los hallazgos de la MEG indican que el número de dipolos de ondas lentas en lóbulos temporales se relaciona con puntuaciones bajas en el examen minimental. La MEG puede ser un método complementario útil en la evaluación y seguimiento del grado de deterioro cognitivo en estos pacientes (AU)

Introduction. In early stages, dementia is a neurodegenerative process with difficult diagnosis. Although well defined clinically, its neurophysiological, neuroradiological and metabolic diagnosis is still unsuccessful. Patients and method. A MEG study using a 148- channel whole-head magnetometer (Magnes 2500 WH) and evaluation by mini mental state examination (MMSE) was performed in 31 subjects. Statistical analyses was made to correlate number of dipoles of slow waves and neuropsychological variables. Results. The 63.3% (21 patients) show slow waves dipoles in temporal lobes (52.3% were bitemporal). Right temporal lobe has 119.5 ± 23.3 dipoles (averaged value), and left temporal lobe has 126.2 ± 19.8 dipoles (averaged value). The 25% (8 patients) shown slow waves dipoles in parietals lobes, 5 of them biparietal. Correlation between MMSE averaged scores and temporal lobe dipoles was r= -0.84. Conclusion. MEG results show that slow waves dipoles number in temporal lobes is related with low scores in the mini mental state examination. MEG could be a usefully complementary method in evaluation and following of degree of cognitive impairment in these patients (AU)

Clínica de la epilepsia en los trastornos del espectro autista / Clinical features of epilepsy in autism spectrum disorders

El autismo es una enfermedad rara, pero está de moda. Se estima una incidencia de 1/1.000 para el autismo infantil precoz, pero en el espectro autista la incidencia puede llegar a ser de 30/1.000. Las características clínicas del autismo son: trastornos cognitivos del lenguaje, falta de interacción social, comportamientos obsesivos con estereotipias y epilepsia. Para algunos autores es un síntoma asociado, y para otros, un síntoma cardinal de la enfermedad. La epilepsia en el autismo, como asociación, ya la citó en 1943 Leo Kanner, al describir en su trabajo inicial de 11 casos que uno de ellos padecía epilepsia. En 1960 se valoró la prevalencia de la epilepsia en los autistas, mucho mayor que en la población normal. Existen cifras dispares, según los autores, pero en realidad las cifras en aumento dependen de la edad: a mayor edad, mayor prevalencia de epilepsia, dato que nos llamó la atención para interesarnos en el tema, y en el que surgieron las primeras preguntas de nuestra investigación en autismo y epilepsia. Las series varían entre el 4 y el 86 por ciento, dependiendo también de la metodología utilizada para confirmar la epilepsia. En nuestra casuística, entre 1 y 18 años de edad, el 20 por ciento de estos niños con trastorno del espectro autista padece algún tipo de crisis epilépticas, y un 80 por ciento padece lo que otros investigadores denominan `crisis subclínicas'. Se presenta la semiología de las crisis subclínicas más importantes que se han encontrado en estos niños, se comentan las enfermedades asociadas al autismo, se discute el concepto de autismo primario y secundario, se explica el porqué de las crisis en el autismo y sus consecuencias como trastorno neuroevolutivo, y se propone una hipótesis interesante dentro de nuestra teoría general del autismo. Asimismo, se comenta también la importancia que tienen en nuestras investigaciones en magnetoencefalografía en el estudio del autismo (AU)

Autism is a rare disease, but is currently in vogue. An incidence of 1/1 000 has been estimated for early childhood autism, but in autism spectrum the incidence can reach 30/1,000. The clinical characteristics of autism are cognitive language disorders, lack of social interaction, obsessive behaviours with stereotypic movements and epilepsy. For some authors it is an associated symptom while for others it is a cardinal symptom of the disease. Epilepsy in autism, as an association, was reported as early as 1943 by Leo Kanner, in describing his initial work involving 11 cases and how one of them suffered from epilepsy. In 1960, the prevalence of epilepsy among autistic patients was evaluated and found to be much higher than in the normal population. The figures differ from author to author, but really they depend on age: the higher the age, the greater the prevalence of epilepsy. It was in fact this detail that drew our attention to this issue, and triggered the first questions in our research into autism and epilepsy. The series vary from 4 to 86%, depending on the methodology used to confirm the epilepsy. In our casuistics, between the ages of 1 and 18 years, 20% of these children with autism spectrum disorders suffer some kind of epileptic seizures, and 80% suffer what other researchers call ‘subclinical seizures’. In this paper, the symptomatology of the most important subclinical seizures that have been observed in these children is presented; the diseases associated with autism are commented on; the concept of primary and secondary autism is discussed; we explain why seizures occur in autism and their consequences as a neurodevelopmental disorder, and we put forward an interesting hypothesis within our general theory of autism. We also comment on the importance that the use of magnetoencephalography in the study of autism has in our research (AU)

El síndrome de savant o idiot savant / Savant or idiot savant syndrome

El síndrome de savant es aún, en la actualidad, muy misterioso; pero, gracias a los avances en los estudios con neuro imagen, especialmente con técnicas MSI (del inglés, magnetic source imaging), se sabe más de él. La teoría, formulada hace largo tiempo, sobre los daños del hemisferio cerebral izquierdo, se ha visto respaldada por la neuroimagen funcional. Su relación con los trastornos del desarrollo o trastornos del espectro autista, está hoy mucho más justificada y puede explicarse desde su neuropatología. Se expone un trabajo de revisión del síndrome en cuanto a la literatura científica, desde su primera descripción, en 1789, por Benjamín Rush, hasta la actualidad. Se comenta la epidemiología y sus manifestaciones clínicas positivas, de brillantez artística y de memoria deslumbrante, a la vez que los aspectos negativos que acompañan a estos pacientes autistas. Se discuten las teorías más importantes, así como la coincidencia clínica con la demencia frontotemporal, la responsabilidad del hemisferio derecho cuando hay alteraciones en el hemisferio contralateral, y las nuevas aportaciones mediante la tomografía por emisión de positrones y la magnetoencefalografía (AU)

Savant syndrome is currently still very mysterious, yet, thanks to the progress made in neuroimaging studies and especially MSI (Magnetic Source Imaging) techniques, a little more is now known about it. The theory, formulated many years ago, about damage to the left hemisphere of the brain has been supported by functional neuroimaging. Its relation to developmental disorders or to autism spectrum disorders is far more justified today and can be explained on the basis of its neuropathology. We present a study based on a review of the scientific literature concerning the syndrome, from the first time it was described back in 1789 by Benjamin Rush up to the present day. We comment on its epidemiology and positive clinical manifestations, involving brilliant artistic talent and dazzling memory, but also the negative aspects suffered by these autistic patients. The most important theories are discussed together with the clinical coincidence with frontotemporal dementia and the responsibility of the right hemisphere when there are alterations in the contralateral hemisphere. The latest contributions made by Positron Emission Tomography and magnetoencephalography will be discussed and a mini-video of a personal case will be projected (AU)

Correlatos neuromagnéticos del lenguaje / The neuromagnetic correlates of language

Los estudios del lenguaje con diferentes técnicas de neuroimagen funcional han evidenciado las estructuras corticales implicadas en las funciones del lenguaje, tanto en sujetos controles como en pacientes con diferentes patologías neurológicas que van a someterse a cirugía cerebral. La magnetoencefalografía (MEG) es una técnica realmente no invasiva, que mide los campos magnéticos generados por el flujo de corriente intracelular producido en las dendritas de las neuronas piramidales. La MEG, además de ofrecer la posibilidad de lateralizar el lenguaje, permite conocer cuáles son las áreas del lenguaje dentro de ese hemisferio dominante, así como establecer los patrones temporales que indican la organización secuencial o en paralelo de las diferentes áreas activadas. Ello permitirá un conocimiento más profundo de las bases fisiológicas que sustentan tanto el lenguaje como otros procesos cognitivos (AU)

Studies of language using different functional neuroimaging techniques have shown the cortical structures to be involved in the functions of language, both in control subjects and in patients with different neurological pathologies who are to undergo brain surgery. Magnetoencephalography (MEG) is a totally non-invasive technique that measures the magnetic fields generated by the flow of intracellular current produced in the dendrites of the pyramidal neurones. MEG also offers the possibility of lateralizing language, so enabling us to know which areas of language lie within the dominant hemisphere and to establish the temporal patterns that reveal the organisation, either in sequence or in parallel, of the different areas that are activated. This will provide us with a deeper understanding of the physiological foundations upholding both language and other cognitive processes (AU)