[Sleep-related movement and behavioural disorders in adults]. / Trastornos del movimiento y de la conducta durante el sueño en el adulto.

Sleep-related movement and behaviour disorders may have an impact on sleep quality and lead to daytime symptoms. These groups of conditions include diseases such as restless legs syndrome, periodic leg movements, and REM and NREM parasomnias. The knowledge of their clinical features and management is of utmost importance for the neurologist and sleep specialist. Frequently, these patients are referred to such specialists and it is relevant to know that certain sleep disorders may be associated with other neurological conditions.

TITLE: Trastornos del movimiento y de la conducta durante el sueño en el adulto.Los trastornos del movimiento y de la conducta durante el sueño pueden tener un impacto en la calidad del sueño del paciente y dar lugar a síntomas diurnos. En estos grupos de enfermedades se incluyen entidades como el síndrome de piernas inquietas, los movimientos periódicos de las piernas y las parasomnias del sueño de movimientos oculares rápidos (REM) y no REM. El conocimiento de sus características clínicas y nociones sobre su manejo es de gran importancia para el neurólogo y especialista en sueño por su frecuencia e impacto en la calidad del sujeto. Con frecuencia, estos pacientes son referidos a dichos especialistas, y es relevante conocer que ciertos trastornos del sueño pueden asociarse a otras enfermedades neurológicas.

[FOXG1, a new gene responsible for the congenital form of Rett syndrome]. / FOXG1, un nuevo gen responsable de la forma congenita del sindrome de Rett.

INTRODUCTION: Rett syndrome (RS) is a neurodevelopmental disorder that affects girls almost exclusively. The identification of mutations in the MECP2 and CDKL5 genes offers genetic confirmation of the clinical diagnosis. The FOXG1 gene appears to be a novel cause of the congenital variant of RS. CASE REPORT: We describe the first Spanish patient with the atypical (congenital) variant of RS with mutation of the FOXG1 gene and the case is compared with 12 patients previously reported in the literature; clinical criteria that suggest alterations in FOXG1 are proposed. The patient was referred at the age of 6 months due to overall retardation, axial hypotonia, microcephaly and a peculiar phenotype. Magnetic resonance imaging of the brain revealed hypoplasia of the corpus callosum, frontal atrophy and ventriculomegaly. The appearance of hand-to-mouth stereotypic movements at 12 months pointed the clinical diagnosis towards an atypical variant of RS, the congenital form; there was progressive improvement of visual contact and interest in her surroundings. Frequent respiratory infections and obstructive sleep apnoea syndrome. At the age of 5 years there was partial control over the axial tone, grasping with the hands, good contact and babbling, without epilepsy or behavioural disorders. The MECP2 and subtelomeric deletion study did not reveal any alterations; two polymorphisms were identified in the CDKL5 gene and a pathogenic mutation was found in FOXG1 (c.624C>G p.Tyr203X). CONCLUSIONS: It has been shown that 92% of patients with mutations in the FOXG1 gene present the congenital form of RS with severe generalised hypotonia, early acquired microcephaly (-3 to -6 standard deviations) and peculiar phenotype. When faced with a diagnosis of RS with no alterations in the MECP2 and CDKL5 genes, especially in the case of the congenital variant, the FOXG1 gene must be investigated. The molecular diagnosis confirms the clinical diagnosis and provides the family with genetic counselling.

[Neurobiological consequences of sleep apnea syndrome in children]. / Consecuencias neurobiológicas del síndrome de apnea del sueño infantil.

INTRODUCTION AND DEVELOPMENT: Sleep disorders in general, and more specifically those related to obstructive sleep apnea syndrome (OSAS) in children, are associated with cognitive and behavioural dysfunctions. Both restriction and fragmentation of sleep as well as intermittent hypoxia are involved in the pathophysiological alterations triggered by this neurobiological comorbidity. The mechanisms that eventually give rise to these neurobehavioural disorders appear to involve a number of biological pathways, particularly oxidative stress and systemic inflammation. CONCLUSIONS: The role played by inter-individual susceptibility, together with the environmental conditions and lifestyle, may account for the larger part of the variance in the phenotype. Moreover, the usual clinical prototype of the patient referred to a children's sleep unit due to snoring has evolved a lot in the past 15 years. We have gone from the patient who presents adenotonsillar hypertrophy with no associated obesity (as was the case in the early nineties) to the prototype of a patient who visits our sleep unit with a slight or moderate adenotonsillar hypertrophy, and with an obese biotype that is very similar to that of the adult patient with OSAS. For this reason we therefore propose the use of the terms type I and type II OSAS in children, and their different manifestations and clinical course are discussed.

Consecuencias neurobiológicas del síndrome de apnea del sueño infantil / Neurobiological consequences of sleep apenea syndrome in children

Introducción y desarrollo. Los trastornos de sueño en general, y más específicamente los relacionados con el síndrome de apnea obstructiva del sueño (SAOS) en niños, se presentan asociados a disfunciones cognitivas y conductuales. Tanto la restricción como la fragmentación del sueño y la hipoxia intermitente están involucradas en la fisiopatología que provoca esta comorbilidad neurobiológica. Los mecanismos que acaban por provocar estas alteraciones neuroconductuales parecenimplicar múltiples vías biológicas, especialmente el estrés oxidativo y la inflamación sistémica. Conclusiones. El papel de la susceptibilidad interindividual, sumado a las condiciones medioambientales y de estilo de vida, puede explicar de manera sustancial la varianza en el fenotipo. Además, el prototipo clínico del paciente remitido a una unidad de sueño infantil por ronquido habitual ha evolucionado en los últimos 15 años. Se está pasando del paciente que presenta una hipertrofia adenoamigdalar sin obesidad asociada (tal como ocurría a principio de los años noventa) al prototipo de paciente que acude anuestra unidad de sueño con una ligera o moderada hipertrofia adenoamigdalar, y de biotipo obeso muy similar a la del paciente adulto con SAOS. Por ello, proponemos la nomenclatura de SAOS infantil en tipo I y tipo II, y discutimos sus diferentesmanifestaciones y curso clínico

Introduction and development. Sleep disorders in general, and more specifically those related to obstructive sleep apnea syndrome (OSAS) in children, are associated with cognitive and behavioural dysfunctions. Both restriction and fragmentation of sleep as well as intermittent hypoxia are involved in the pathophysiological alterations triggered by thisneurobiological comorbidity. The mechanisms that eventually give rise to these neurobehavioural disorders appear to involve a number of biological pathways, particularly oxidative stress and systemic inflammation. Conclusions. The role played by inter-individual susceptibility, together with the environmental conditions and lifestyle, may account for the larger part of the variance in the phenotype. Moreover, the usual clinical prototype of the patient referred to a children’s sleep unit due to snoring has evolved a lot in the past 15 years. We have gone from the patient who presents adenotonsillar hypertrophy with noassociated obesity (as was the case in the early nineties) to the prototype of a patient who visits our sleep unit with a slight or moderate adenotonsillar hypertrophy, and with an obese biotype that is very similar to that of the adult patient with OSAS. Forthis reason we therefore propose the use of the terms type I and type II OSAS in children, and their different manifestations and clinical course are discussed

[Face recognition in autism]. / Reconocimiento de caras en autismo.

INTRODUCTION: We conducted a survey of the literature on face recognition (FR), an activity that is essential for social relations and their dynamics. Unlike the recognition of non facial objects, this type of recognition is a special process since it is based on the detection of individual features. The most characteristic clinical parameter of autistic subjects is their inability to relate socially, possibly due to the difficulty they have in processing faces, although they are more skilled at recognising objects. DEVELOPMENT: We describe the two mechanisms involved in FR, one based on features and the other referring to the whole. The latter can be further divided into overall processing that allows a whole image to be compared with another previously assimilated image, and the processing of the arrangement of a face that is recognised as a whole. These may correspond to two different neuronal pathways. During the first days of life, the newborn baby has a predilection for faces in their feature and overall aspects, and processing of the arrangement is slower. Visual development in autistic children is erratic, similar to the level of a newborn infant, and their lack of interest for human faces is apparent during the first year of life, as they look at everything as if they were objects, that is, by features. CONCLUSIONS: The analysis of the literature enabled us to determine how FR mechanisms develop in the earliest days of the infant s life. It also highlighted the importance of the integrity of the pathway that facilitates stimulation for the recognition of facial arrangement, which is altered in autistic children perhaps from the peripheral area to the cortex. Further work on peripheral pathways and the fundamental cortical connections that are affected in autistic subjects will help us to understand the inefficiency of their facial arrangement recognition system.

Reconocimiento de caras en el autismo / Face recognition in autism

Introducción. Se realiza una revisión bibliográfica sobre el reconocimiento de caras (RDC), actividad fundamental para las relaciones sociales y su dinámica. Este tipo de reconocimiento es un proceso especial, en contraste con el reconocimiento de objetos no faciales, pues se basa en la detección de características individuales. El parámetro clínico más característico de los autistas es su imposibilidad para la relación social, posiblemente por su dificultad para el procesamiento de caras, aunque poseen una mayor habilidad en el reconocimiento de objetos. Desarrollo. Se plantean los dos mecanismos en el RDC, el de los rasgos y el de conjunto. El segundo comprende el procesamiento global, que permite comparar la totalidad de la imagen con una imagen previamente asimilada, y el procesamiento de la configuración de la cara reconocida como un todo; ambos pueden corresponder a dos redes neuronales distintas. En los primeros días de vida, el recién nacido tiene preferencia por las caras en sus aspectos de rasgos y global, y es más lento el proceso de la configuración. El desarrollo visual en los niños autistas es errático, como si fuese el nivel de un recién nacido, y su desinterés por las caras humanas es evidente en el primer año de vida, al mirar todo como objetos, por rasgos. Conclusiones. El análisis de la bibliografía ha permitido plantear cómo se desarrollan los mecanismos de lRDC desde los primeros días de vida, y la importancia que desempeña la integridad de la vía que facilita la estimulación para el reconocimiento de la configuración facial, alterada en los niños autistas, posiblemente desde la periferia al córtex. Nuevos trabajos sobre las vías periféricas y las conexiones corticales fundamentales afectadas en autistas ayudarán a comprender la ineficiencia de su sistema de reconocimiento de la configuración facial (AU)

[Cognitive evoked potentials in autistic children]. / Potenciales evocados cognitivos en niños autistas.

AIMS: The aim of this study was to examine the latency, amplitude and distribution of N400 potential in order to evaluate the semantic processing capacity in autistic children and in children suffering from Asperger s syndrome (AS), and to compare them with a control group. PATIENTS AND METHODS: 24 autistic children, six boys with AS and 25 controls, aged between 6 and 14 years old. The cases were examined using the DSM IV diagnostic criteria. Auditory stimulation was performed with pairs of congruent and incongruent words: two lists of 20 pairs of semantically related words (congruent) and 20 pairs of words with no semantic relationship whatsoever (incongruent). RESULTS: The most striking parameter is the increase in latency in N400 for the group of autistic children, which did not occur in the group of children with AS. Maximum N400 negativity for the children with autism was found in the left frontocentral region. No significant differences were observed for the amplitude of N400 between the three groups that were studied. CONCLUSION: Neurophysiologically, the autistic children and those affected by AS perhaps use different neuronal networks in semantic processing. The N400 wave can be a valid test for monitoring verbal processing in these children.

Potenciales evocados cognitivos en niños autistas / Cognitive evoked potentials in autistic children

Objetivo. Estudiar la latencia, amplitud y distribución del potencial N400 para valorar la capacidad de procesamiento semántico en niños autistas y en niños con síndrome de Asperger (SA) y compararlos con un grupo control. Pacientes y métodos. 24 niños autistas, seis niños con SA y 25 controles, con edades comprendidas entre 6 y 14 años. Se utilizaron los criterios diagnósticos del DSM-IV para los casos. Se realizó una estimulación auditiva con pares de palabras congruentes e incongruentes: dos listas de 20 pares de palabras relacionadas semánticamente (congruentes) y 20 pares de palabras sin relación semántica alguna (incongruentes). Resultados. El parámetro más llamativo es el incremento de la latencia en la N400 para el grupo de autistas, que no fue así en el grupo de niños con SA. La máxima negatividad de la N400 para los niños con autismo se localiza en la región frontocentral izquierda. No se observaron diferencias significativas para la amplitud de la N400 entre los tres grupos estudiados. Conclusión. Neurofisiológicamente, los niños autistas y los afectos de SA posiblemente utilizan redes neuronales diferentes para el procesamiento semántico. La onda N400 puede ser un test válido para el seguimiento del procesamiento verbal de estos niños (AU)

Aims. The aim of this study was to examine the latency, amplitude and distribution of N400 potential in order to evaluate the semantic processing capacity in autistic children and in children suffering from Asperger’s syndrome (AS), and to compare them with a control group. Patients and methods. 24 autistic children, six boys with AS and 25 controls, aged between 6 and 14 years old. The cases were examined using the DSM IV diagnostic criteria. Auditory stimulation was performed with pairs of congruent and incongruent words: two lists of 20 pairs of semantically related words (congruent) and 20 pairs of words with no semantic relationship whatsoever (incongruent). Results. The most striking parameter is the increase in latency in N400 for the group of autistic children, which did not occur in the group of children with AS. Maximum N400 negativity for the children with autism was found in the left frontocentral region. No significant differences were observed for the amplitude of N400 between the three groups that were studied. Conclusion. Neurophysiologically, the autistic children and those affected by AS perhaps use different neuronal networks in semantic processing. The N400 wave can be a valid test for monitoring verbal processing in these children (AU)

[Nocturnal polysomnogram in childhood autism without epilepsy]. / Polisomnograma nocturno en el autismo infantil sin epilepsia.

AIMS: To evaluate the presence of epileptiform discharges and the organisation of nocturnal sleep of autistic children without nocturnal polysomnographic epileptic seizures. SUBJECTS AND METHODS: Cross section analysis. SUBJECTS: 21 boys and girls with autistic spectrum using DSM IV criteria between the ages of 4 and 12, compared with a control group made up of normal children of the same ages. METHODS: nocturnal polysomnogram with a minimum efficiency of 75%. ANALYSIS: t test to compare the cycles and phases of sleep with significance p< 0.05. RESULTS: SUBJECTS presented a maximum of four sleep cycles compared with five or six in the control subjects. From the first third of the night onwards there was an increase in the slowest phases. 66% presented epileptiform paroxysmal discharges, all of which originated in the anterior half of the brain. CONCLUSION: Sleep is not destructured, but it is reduced in length, with epileptiform paroxysms of predominantly frontal origin. This could indicate that these two parameters are intrinsic to the autistic spectrum, as well as indicating a more focused origin of the generalised picture which is possibly closely related with the qualitative alteration of the social experiences of these children.

Polisomnograma nocturno en el autismo infantil sin epilepsia / Nocturnal polysomnogram in childhood autism without epilepsy

Objetivo. Valorar la presencia de descargas epileptiformes y la organización del sueño nocturno en niños autistas sin crisis epilépticas polisomnográficas nocturnas. Sujetos y métodos. Diseño analítico de sección transversal. Sujetos: 21 niños y niñas con espectro autista según DSM-IV entre 4 y 12 años de edad, compa ados con un grupo control de niños normales de las mismas edades. Métodos: polisomnograma nocturno con eficiencia mínima del 75 por ciento. Análisis: test t para comparar los ciclos y fases del sueño con significación p< 0,05. Resultados. Los sujetos presentaron un máximo de cuatro ciclos de sueño frente a cinco o seis de los controles. Se produjo un incremento de las fases más lentas a partir del primer tercio de la noche. Un 66 por ciento presentó descargas paroxísticas epileptiformes, todas con origen en la mitad anterior del cerebro. Conclusión. No existe desestructuración del sueño, pero sí reducción de su duración, con paroxismos epileptiformes de origen predominantemente frontal, lo que puede indicar que estos dos parámetros son intrínsecos al espectro autista, además de señalar un origen más focal del cuadro generalizado, y posiblemente muy relacionados con la alteración cualitativa de las vivencias sociales de esos niños (AU)