El funcionamiento cognitivo como endofenotipo de la anorexia nerviosa. Estudio en familiares no afectados por la enfermedad / Cognitive functioning as an endophenotype of anorexia nervosa. A study in first-degree relatives unaffected by the disease

Resumen El perfil cognitivo de los pacientes con anorexia nerviosa se caracteriza por dificultades en la flexibilidad mental y en la coherencia central. El objetivo de este trabajo fue analizar si los familiares de primer grado no afectados de los pacientes presentan estas dificultades cognitivas, que podrían representar rasgos endofenotípicos de la enfermedad. Fueron estudiadas 34 mujeres: 17 familiares de primer grado (madres y hermanas) de pacientes con anorexia nerviosa y 17 controles sanos agrupados por edad y escolaridad. Se consideraron el índice de masa corporal, la ansiedad, la depresión, los síntomas obsesivo-compulsivos y los relacionados con los trastornos alimentarios. Se evaluó la coherencia central, mediante la copia de la Figura Compleja de Rey, y la flexibilidad mental, mediante el test de Stroop, el test de los trazos B y el test de fluencia fonológica. Los familiares de pacientes con anorexia nerviosa presentaron un menor rendimiento en las medidas de coherencia central (p < .05) y en fluencia fonológica (p < .05) que los controles sanos. Se observó una correlación entre el test de Stroop y los síntomas de depresión y trastornos alimentarios (p < .05). Los familiares de primer grado no afectados de pacientes con anorexia nerviosa presentaron dificultades en la coherencia central y, en menor grado, en la flexibilidad mental. Los resultados en los familiares indican que este perfil podría ser mediado genéticamente, constituyendo un rasgo característico de la anorexia nerviosa y, por ende, un posible candidato a endofenotipo neuropsicológico de esta enfermedad.

Abstract The cognitive profile of patients with anorexia nervosa is characterized by difficulties in central coherence and mental flexibility. Central coherence is defined by the ability to integrate incoming information in its own context, and weakness in central coherence is characterized by poor overall processing and superior detail processing. Mental flexibility is defined by the ability to change the course of a thought or action according to the demands of the environment. Alterations in this cognitive domain generate rigid and inflexible behavior. An open question in the literature is whether these cognitive characteristics are a transient state derived from the disease or whether they are stable traits associated with anorexia nervosa and endophenotypical features of this disease. The concept of endophenotype refers to the internal phenotype that is not clinically appreciable but can be observed indirectly through deficits that arise in the performance of certain neuropsychological tests. In recent years the search for endophenotypes has been renewed in the field of psychiatry as they would constitute an important route for the understanding of the biological and genetic bases of mental illnesses, constituting markers that allow a diagnosis before the onset of clinical symptomatology. For a cognitive marker to be considered an endophenotype it must meet a series of characteristics such as being measurable, inherited, found in patients with and without active disease and in first-degree relatives not affected by the disease. The aim of the present study was to assess whether difficulties in central coherence and mental flexibility are shared by unaffected first-degree relatives of patients with anorexia nervosa and thus constitute an endophenotypical feature of this disease. This is a cross-sectional, descriptive-comparative study in which 34 women participated: 17 unaffected first-degree relatives of patients with anorexia nervosa (mothers and sisters) and 17 healthy controls matched by age and education. For the study of central coherence the copy of Rey's Complex Figure was used and to assess set-shifting the Stroop test, the Trail Making Test B and the Phonological Fluency test were used. Demographic and clinical aspects such as age, educational level, body mass index, anxiety, depression, obsessive-compulsive and eating disorder related symptoms were also evaluated. First-degree relatives of patients with anorexia nervosa showed lower performance on measures of central coherence (p < .05) and phonological fluency (p < .05) than healthy controls. A correlation was observed between the Stroop test and depression and eating disorders symptoms (p < .05). The results of this study show that unaffected first-degree relatives of patients with anorexia nervosa presented alterations in central coherence and, to a lesser degree, in mental flexibility. These results, in addition to previous research in which difficulties persisted even after recovery, indicate that these alterations could be genetically mediated, constituting a characteristic trait of anorexia nervosa and therefore a possible candidate for neuropsychological endophenotype of this disease. Regarding practical implications of the study, the findings reinforce the importance of cognitive remediation treatments not only for patients with anorexia nervosa but also emphasize that they could be useful for unaffected family members. Taking into account that family intervention is a widely used tool in the psychological treatment of anorexia, improving the perception of the patient and his relatives about cognitive biases, could contribute to raising awareness of the disease, something that patients with anorexia nervosa do not usually have, and generate a positive impact on the response to treatment as a whole.

Funciones cognitivas en la descendencia de pacientes con trastorno bipolar I / Psychopathological and neuropsychological profile in the offspring of patients with bipolar disorder type I

Resumen Objetivo: Describir las características neuropsicológicas de niños y adolescentes descendientes de padres con antecedentes de TB I, respecto a la aplicación de una prueba estandarizada de inteligencia. Materiales y métodos: Estudio observacional descriptivo de corte transversal, en donde los autores investigaron el Coeficiente Intelectual Total; Índice de compresión verbal; Índice de Razonamiento Perceptual; Índice de Memoria de trabajo; Índice de Velocidad de Procesamiento. Se evaluaron (n=30) descendientes al aplicar varias subpruebas de la Escala de inteligencia de Weschler para niños, (WISC -IV). Resultados: El Coeficiente Intelectual Total de los participantes con un 63,3% está por debajo del promedio de la curva de distribución normal, según la estandarización del test de inteligencia aplicado. Clasificando la tendencia de la muestra como un promedio normal bajo, en cuanto a la muestra evaluada. Los índices de memoria de trabajo y compresión verbal fueron las funciones cognitivas con puntuaciones más bajas en la muestra. Discusión: Nuestros hallazgos sugieren un riesgo en hijos de pacientes con TBI, que puede contribuir a un incremento cuantitativo de las alteraciones cognitivas, especialmente el índice de memoria de trabajo y compresión verbal. Estos hallazgos pueden sugerir un posible endofenotipo del TB I y su descendencia, en relación a la presentación temprana de alteraciones cognitivas en este grupo de riesgo. Dichos hijos podrían ser un punto de partida para realizar estudios que determinen predicción y realizar así un abordaje temprano.

Abstract Objective: To describe the neuropsychological characteristics of offspring children and adolescents of patients with bipolar disorder type 1 diagnosis through the application of a standardized intelligence test. Materials and methods: In this descriptive cross-sectional observational study, the authors investigated aspects such as Intelligence Quotient, Verbal Comprehension Index, Perceptual Reasoning Index, Working Memory Index, and Processing Speed Index. Here, 30 descendants were evaluated by applying several subtests of the Wechsler Intelligence Scale for Children (WISC-IV). Results: The Total Intelligence Quotient of 63.3% of the participants is below the average of the Normal Distribution curve according to the standardization of the intelligence test applied which classifies the tendency of the sample as a low normal average. The working memory and verbal comprehension indexes were the cognitive functions with the lowest scores in the sample. Discussion: Our findings suggest a risk in children of patients with Bipolar Disorder type I, which may contribute to a quantitative increase of cognitive disorders, especially in terms of working memory and verbal comprehension indexes. These findings may indicate a possible endophenotype of Bipolar Disorder type I patients and their offspring in regards to the early manifestation of cognitive disorders in this risk group. These children could be a target for studies that determine prediction and thus perform an early treatment.

Estudios de agregación plaquetaria como endofenotipo de las alteraciones hereditarias de la fibra colágena / Platelet aggregation studies as an endophenotype of hereditary disorders of collagen fiber

Introducción: Las plaquetas contribuyen a la hemostasia y la interrupción heredada o adquirida; en sus procesos bioquímicos pueden alterar la función plaquetaria. Estos trastornos de agregación se han asociado a enfermedades genéticas con afectación del tejido conectivo como el síndrome Ehlers-Danlos, cuyo diagnóstico diferencial con el espectro de hipermovilidad articular resulta difícil clínica y molecularmente. Estas entidades con afectación en las fibras colágenas y diferente repercusión clínica precisan diferenciales en su diagnóstico clínico. Métodos: Se revisaron 353 historias clínicas de pacientes atendidos en el Servicio de Genética del Hospital Pediátrico William Soler desde septiembre del 2009 al 2012, con diagnóstico de hipermovilidad articular por criterios de Beighton y de Ehlers-Danlos según Villefranche (1997). Se incluyó a los pacientes de 5-18 años con resultados documentados del estudio de agregación plaquetaria, valorados por especialistas en hematología. Resultados: Se encontraron trastornos de agregación plaquetaria en 79 de 86 pacientes (92 por ciento). En 7 casos con hipermovilidad de 65 con este diagnóstico (10 por ciento), los resultados fueron negativos. Los 21 con síndrome Ehlers-Danlos tuvieron afectaciones con los fosfolípidos plaquetarios. La hipermovilidad articular estuvo asociada a la combinación difosfato de adenosina (ADP)-epinefrina y el Ehlers-Danlos a la combinación ADP-epinefrina-colágeno-fosfolípidos. Conclusiones: Los pacientes con hipermovilidad articular mostraron asociación a defectos de liberación de gránulos con agonistas como el ADP-epinefrina y los Ehlers-Danlos con la disponibilidad de los fosfolípidos, relacionados con el cambio de forma plaquetaria. Este resultado puede ser una herramienta para conocer el endofenotipo funcional plaquetario como elemento diferencial en los trastornos de la fibra colágena(AU)

Introduction: Platelets contribute to hemostasis and inherited or acquired interruption; in its biochemical processes it can alter platelet function. These aggregation disorders have been associated with genetic diseases with connective tissue involvement such as Ehlers-Danlos syndrome, whose differential diagnosis with the spectrum of joint hypermobility is clinically and molecularly difficult. These entities with involvement of the collagen fibers and different clinical repercussions require differentials in their clinical diagnosis. Methods: 353 medical records of patients attended in the Genetics service of the William Soler Pediatric Hospital from September 2009 to 2012, with a diagnosis of joint hypermobility by Beighton and Ehlers-Danlos criteria according to Villefranche (1997) were reviewed. Patients aged 5-18 years were included with documented results of the platelet aggregation study, assessed by specialists in hematology. Results: Platelet aggregation disorders were found in 79 of 86 patients (92 percent). In 7 cases with hypermobility of 65 with this diagnosis (10 percent), the results were negative. The 21 with Ehlers-Danlos syndrome had affectations with platelet phospholipids. Joint hypermobility was associated with the combination adenosine diphosphate (ADP) -epinephrine and the Ehlers-Danlos with the combination ADP-epinephrine-collagen-phospholipids. Conclusions: Patients with joint hypermobility showed an association to granule release defects with agonists such as ADP-epinephrine and Ehlers-Danlos with the availability of phospholipids, related to platelet shape change. This result can be a tool to know the platelet functional endophenotype as a differential element in collagen fiber disorders(AU)

Un cuarto de siglo de investigación genética en los trastornos neuropsiquiátricos en Costa Rica

El estudio de la base genética de los trastornos neuropsiquiátricos se inició en Costa Rica hace más de 25 años. En este tiempo se han realizado investigaciones enfocadas en diferentes trastornos: esquizofrenia, trastorno bipolar, demencia de Alzheimer, trastorno obsesivo compulsivo, trastorno obsesivo compulsivo, trastorno por déficit de atención y síndrome de Tourette. Los estudios realizados han tenido una amplia variación en lo que se refiere a diseño (ligamiento/asociación), muestra utilizada (familias/parejas de hermanos afectados/tríos), cobertura genómica (estudios con genes candidatos/tamizajes de todo el genoma) y definición del fenotipo (categoría diagnóstica/clasificación sindrómica/endofenotipo). Presentamos un resumen de los principales hallazgos genómicos obtenidos en estos estudios multidisciplinarios y discutimos la importancia, lecciones y retos de la investigación genética en trastornos psiquiátricos complejos.

In Costa Rica, the study of the genetic basis of neuropsychiatric disorders started more than 25 years ago. During this time, different research efforts have focused on several disorders: schizophrenia, bipolar disorder, Alzheimer's disease, obsessive-compulsive disorder, attention deficit/hyperactivity disorder, and Tourette syndrome. The studies have had a wide scope regarding design (linkage/association), sample used (families/sib pairs/trios), genome coverage (candidate gene studies/genome-wide scans), and phenotype definition (diagnostic category/syndromic classification/endophenotype). Here we present a summary of the main genomic findings of these multidisciplinary studies, and discuss the importance, lessons, and challenges of genetic research of complex psychiatric disorders.

Endofenótipo da dislexia: hereditariedade, alterações de linguagem e influências do processamento fonológico e memória visual nas habilidades de leitura, escrita e matemática / Endophenotype of dyslexia: heredity, language changes and influences of phonological processing and visual memory skills in reading, writing and math

Os fatores genéticos e hereditários têm ganhado um foco especial como causa da dislexia, entretanto, há muito a ser estudado na busca de sua etiologia. Há vasta literatura associando o processamento fonológico ao aprendizado da leitura e escrita, porém pouco é investigado sobre a participação do processamento visual nas habilidades de leitura. Atualmente, a relação entre processamento fonológico e matemática tem sido apontada nas publicações científicas, sendo ainda pouco estudada, havendo necessidade de melhor compreensão entre a relação dessas habilidades, bem como as comorbidades entre dislexia e problemas na matemática. Este estudo teve como objetivo geral descrever o perfil endofenótipo dos sujeitos com dislexia referente à hereditariedade e influência do processamento fonológico e memória sequencial visual nas dificuldades da linguagem escrita e na matemática, no intuito de identificar semelhanças e diferenças no processamento da informação escrita entre indivíduos com dislexia e bons leitores. Participaram 35 indivíduos com o diagnóstico de dislexia e 46 bons leitores, de 8 a 13 anos e ambos os sexos. Nos dois grupos foram avaliadas as habilidades do processamento fonológico (consciência fonológica, acesso ao léxico e memória de trabalho fonológica), leitura de palavras, pseudopalavras, compreensão de texto, escrita e habilidades matemáticas. As habilidades do processamento fonológico e memória visual foram correlacionadas com a leitura, escrita e matemática nos dois grupos. Foi utilizado o Teste de Correlação de Pearson para correlacionar tais habilidades, e o Teste Qui-Quadrado e Teste U de Mann-Whitney para comparar o desempenho entre os grupos, adotando-se nível de significância de 5%. Encontrou-se que o histórico familial de problemas de aprendizagem esteve presente em mais da metade do grupo com dislexia, demonstrando que este é um importante fator de risco. Os indivíduos com dislexia apresentam pior...

Genetic and hereditarity factors have gained a special focus as the cause of dyslexia, however, there is much to be studied in the search for its etiology. There is extensive literature linking phonological processing to reading and writing learning, but the participation of visual processing in reading skills is little investigated. Currently, the relationship between phonological processing and mathematics has been identified in scientific publications, but still scarcely studied, there is need for better understanding the relationship between these skills as well as the comorbidities between dyslexia and problems in mathematics. This study aimed to describe the endophenotype profile of the subjects with dyslexia related to hereditarity and influence of phonological processing and visual sequential memory difficulties in written language and mathematics, in order to identify similarities and differences in written information processing between individuals with dyslexia and good readers. Participated in the study 35 diagnosed with dyslexia and 46 good readers, from 8 to 13 years old, both genders. Both groups were assessed the phonological processing skills (phonological awareness, lexical access and phonological working memory), words and pseudo words reading, reading comprehension, writing and math skills. The skills of phonological processing and visual memory were correlated with reading, writing and math in both groups. It was used the Pearson's Correlation Test to correlate these skills, and the Chi-square Test and Mann-Whitney Test to compare the performance between the groups, adopting a significance level of 5%. Family history of learning problems was present in more than half of the group with dyslexia, demonstrating that this is an important risk factor. Individuals with dyslexia performed worse in the phonological processing...

Endofenótipo da dislexia: hereditariedade, alterações de linguagem e influências do processamento fonológico e memória visual nas habilidades de leitura, escrita e matemática / Endophenotype of dyslexia: heredity, language changes and influences of phonological processing and visual memory skills in reading, writing and math

Os fatores genéticos e hereditários têm ganhado um foco especial como causa da dislexia, entretanto, há muito a ser estudado na busca de sua etiologia. Há vasta literatura associando o processamento fonológico ao aprendizado da leitura e escrita, porém pouco é investigado sobre a participação do processamento visual nas habilidades de leitura. Atualmente, a relação entre processamento fonológico e matemática tem sido apontada nas publicações científicas, sendo ainda pouco estudada, havendo necessidade de melhor compreensão entre a relação dessas habilidades, bem como as comorbidades entre dislexia e problemas na matemática. Este estudo teve como objetivo geral descrever o perfil endofenótipo dos sujeitos com dislexia referente à hereditariedade e influência do processamento fonológico e memória sequencial visual nas dificuldades da linguagem escrita e na matemática, no intuito de identificar semelhanças e diferenças no processamento da informação escrita entre indivíduos com dislexia e bons leitores. Participaram 35 indivíduos com o diagnóstico de dislexia e 46 bons leitores, de 8 a 13 anos e ambos os sexos. Nos dois grupos foram avaliadas as habilidades do processamento fonológico (consciência fonológica, acesso ao léxico e memória de trabalho fonológica), leitura de palavras, pseudopalavras, compreensão de texto, escrita e habilidades matemáticas. As habilidades do processamento fonológico e memória visual foram correlacionadas com a leitura, escrita e matemática nos dois grupos. Foi utilizado o Teste de Correlação de Pearson para correlacionar tais habilidades, e o Teste Qui-Quadrado e Teste U de Mann-Whitney para comparar o desempenho entre os grupos, adotando-se nível de significância de 5%. Encontrou-se que o histórico familial de problemas de aprendizagem esteve presente em mais da metade do grupo com dislexia, demonstrando que este é um importante fator de risco. Os indivíduos com dislexia apresentam pior...

Genetic and hereditarity factors have gained a special focus as the cause of dyslexia, however, there is much to be studied in the search for its etiology. There is extensive literature linking phonological processing to reading and writing learning, but the participation of visual processing in reading skills is little investigated. Currently, the relationship between phonological processing and mathematics has been identified in scientific publications, but still scarcely studied, there is need for better understanding the relationship between these skills as well as the comorbidities between dyslexia and problems in mathematics. This study aimed to describe the endophenotype profile of the subjects with dyslexia related to hereditarity and influence of phonological processing and visual sequential memory difficulties in written language and mathematics, in order to identify similarities and differences in written information processing between individuals with dyslexia and good readers. Participated in the study 35 diagnosed with dyslexia and 46 good readers, from 8 to 13 years old, both genders. Both groups were assessed the phonological processing skills (phonological awareness, lexical access and phonological working memory), words and pseudo words reading, reading comprehension, writing and math skills. The skills of phonological processing and visual memory were correlated with reading, writing and math in both groups. It was used the Pearson's Correlation Test to correlate these skills, and the Chi-square Test and Mann-Whitney Test to compare the performance between the groups, adopting a significance level of 5%. Family history of learning problems was present in more than half of the group with dyslexia, demonstrating that this is an important risk factor. Individuals with dyslexia performed worse in the phonological processing...

Model endophenotype for bipolar disorder: Qualitative Analysis, etiological factors, and research areas / Modelo endofenotipo de Trastorno Bipolar: Análisis cualitativo, factores etiológicos y las áreas para las cuales la investigación / Modelo de Endofenótipo do Transtorno Bipolar: Análise qualitativa, fatores etiológicos e âmbitos de investigação abordados

The aim of this study is to present an updated view of the writings on the endophenotype model for bipolar disorder using analytical methodologies. A review and analysis of networks was performed through descriptors and keywords that characterize the composition of the endophenotype model as a model of health. Information was collected from between 1992 and 2014, and the main thematic areas covered in the articles were identified. We discuss the results and question their cohesion, emphasizing the need to strengthen and identify the points of connection between etiological factors and characteristics that make up the model of endophenotypes for bipolar disorder.

El objetivo de este trabajo es presentar una visión actualizada de los escritos del modelo endofenotipo para el trastorno bipolar, el uso de las metodologías analíticas. Se realizó una revisión de este tipo de literatura y un análisis de las redes a través de descriptores y palabras clave que caracterizan la composición del modelo endofenotipo como modelo de salud. El momento de la recolección de la información se produjo entre los años 1992-2014, la identificación de las principales áreas temáticas incluidas en los artículos. Se discuten los resultados para la consolidación del modelo de endofenotipos, cuestionando la cohesión y haciendo hincapié en la necesidad de fortalecer e identificar los puntos de conexión entre los factores etiológicos y características que conforman el modelo de endofenotipos para el trastorno bipolar.

O objetivo do presente estudo é o de apresentar uma visão atualizada sobre a produção bibliográfica do modelo de endofenótipo para o transtorno bipolar, recorrendo às metodologias analíticas. Foi realizada para tal uma revisão da literatura e uma análise de redes por meio de descritores e palavras-chaves, que caracterizam a composição do modelo de endofenótipo como um modelo de saúde. O período de recolha das informações ocorreu entre os anos de 1992-2014, identificando nos principais artigos os âmbitos temáticos abordados. Discutem-se os resultados obtidos para a consolidação do modelo de endofenótipos, questionando a coesão e ressaltando a necessidade de reforçar e identificar os pontos de ligação entre os fatores etiológicos e as características que compõe o modelo de endofenótipos para o transtorno bipolar.

Organización de las redes cerebrales / Organization of brain networks

El procesamiento de información por el cerebro se basa en sistemas de redes (networks) que poseen propiedades estructurales y funcionales derivadas de su extrema complejidad. Al tratarse de sistemas complejos con propiedades dinámicos no lineares, las redes se auto organizan permanentemente para adecuarse tanto a los procesamientos rápidos, como en el caso de las funciones cognitivas o ejecutivas, como a las más lentas, derivadas de la capacidad de generar cambios plásticos para adaptarse a las situaciones cambiantes de los entornos externos e internos. El estudio de la conectividad en el SNC se ha sistematizado por teorías de gráficas, modelos simples de un sistema, basados en conjuntos de nodos y márgenes o bordes que poseen propiedades de pequeño mundo (ni azarística, ni regular) de modo tal que el conectoma se organiza en los pequeños volúmenes relativos del cerebro permietiendo una alta eficiencia a bajo costo dada la corta distancia ente nodos centrales que procesan gran cantidad de información. Las proyecciones largas entre regiones distantes del SNC si bien eficaces en las funciones integradoras son costosas en estructura y metabolismo, y por ello vulnerables tanto en el desarrollo como en patologías, como la enfermedad de Alzheimer, la esquizofreia, la epilepsia, el ADHD la esclerosis múltiple, etc. Se conceptualiza al conectoma como fenotipo intermedio o endofenotipo con características heredables modificables en las distintas etapas de la vida, desde el desarrollo pre y perinatal hasta el envejecimiento.

The processing of information by the brain is based on systems of networks that have both structural and functional properties, given their extreme complexity. Because they consist in complex systems with nonlinear dynamic properties, the networks organize themselves permanently to adjust either to quick processings, as is the case with cognitive or executive functions and to the slowest processings which result from the capability of generating plastic changes to adapt to the changing contexts of the external and internal environments. The study of connectivity in the CNS has been systematized by graphics theories, which consist in simple models of a system based on sets of nodes and margins or borders that have properties of a small-world network (neither at random nor regular), so that the connectome is organized in the small relative volumes of the brain, enabling a high efficiency at a low cost, given the short distance between central nodes that process a large amount of information. Although the long projections between the regions that are far from the CNS are efficacious in the integrative functions, they are costly in structure and metabolism, and therefore, vulnerable both in development as well as in pathologies such as Alzheimer's Disease, schizophrenia, epilepsy and ADHD in multiple sclerosis, etc. The author conceptualizes the connectome as an intermediate phenotype or endophenotype with modifying inheritable characteristics in the different stages of life, from the pre- and perinatal development until ageing.

Neurología funcional del blefaroespasmo / Functional neurology of blepharospasm

El blefaroespasmo esencial benigno cursa con movimientos repetitivos anormales del cierre de los párpados y espasmo del músculo orbicular de los ojos. Modernas teorías postulan que este trastorno del movimiento se origina por alteraciones en el procesamiento de la información aferente, con posterior desintegración de dicha información a nivel del programa neural sensorimotor que existe en el sistema nervioso central, que se manifiesta luego como movimiento anormal en los individuos genéticamente susceptibles. Diferentes investigaciones que incluyen estudios imagenológicos, genéticos y neurofisiológicos han proporcionado nuevos hallazgos acerca de las áreas neurales involucradas en esta patología y la forma como se genera este trastorno. Dentro de estas investigaciones sobresale el estudio del reflejo del parpadeo obtenido eléctricamente, el cual consta de tres respuestas llamadas no-nociceptiva (R1), nociceptiva (R2) y ultranociceptiva (R3). Dicho reflejo y, principalmente, la respuesta refleja ultranociceptiva (R3) parece ser muy útil para entender más profundamente la fisiopatología de esta distonía focal y realizar la endofenotipificación funcional y seguimiento en la neuro rehabilitación correspondiente de este complejo problema neurológico.

Benign essential blepharospasm is characterized by abnormal repetitive movements of lid closure and spasm of the orbiculari oculi muscles. Modern theories postulate that this movement disorder originates by abnormal processing of afferent information with further disintegration of the sensorimotor neural program at central levels of the nervous system all of which is seen as dystonic movements in genetically susceptible people. Different investigations including neuroimagin, genetic and neurophysiological studies have discovered new findings on what structures are involved and how this abnormal movement is generated. Among these research is noteworthy the study of electrically elicited blink reflex. It consists of three responses called non-nociceptive (R1), nociceptive (R2) and ultranociceptive (R3). Such blink reflexes, mostly the ultranociceptive response (R3), seem to be very useful to understand more deeply the pathophysiology of this focal dystonia, to perform the functional endophenotyping and to do a more appropriate follow-up of this complex neurological problem.