Alteraciones de la cognición social en personas de alto riesgo clínico de psicosis: Una aproximación desde su actividad cerebral evocada

Doctor en PsicologíaLos déficits neurocognitivos presentes en CHR han sido ampliamente estudiados y se explicarían por alteraciones en áreas corticales multimodales. Las alteraciones en cognición social se han reportado con datos contradictorios, especialmente en reconocimiento facial de emociones y teoría de la mente. Sin embargo, evidencia reciente apunta a que estos déficits podrían asociarse a déficits en el procesamiento sensorial lo que puede ser medido a través de los potenciales relacionados a eventos (ERP) visuales como el complejo N170 y N250 principalmente en la vía Magnocelular. Conocer la relación entre estas variables, puede aportar a comprender esta etapa pre-psicótica y ayudar en el desarrollo de marcadores de diagnóstico temprano y nuevas terapias. El objetivo de este trabajo es establecer la presencia de déficit en tareas de cognición social que requieran actividad de la vía magnocelular en sujetos con CHR. Método: se evaluaron controles sanos (n = 16) y sujetos CHR (n = 6) diagnosticados a través de la Structured Interview for Prodromal Symptoms (SIPS). A ambos grupos se les presentaron tareas de reconocimiento facial de emociones y teoría de la mente cuyos estímulos presentaban filtros de alta frecuencia espacial (HSF) y baja frecuencia espacial (LSF) diseñados para evaluar el funcionamiento de las vías parvocelular y magnocelular respectivamente. Durante la ejecución de esta tarea se registró un electroencefalograma (EEG) de 64 canales Biosemi y luego se obtuvo un ERP. Resultados: Existen diferencias en el rendimiento neurocognitivo entre ambos grupos, no se encontraron diferencias en el número de aciertos en tareas de cognición social, sin embargo existen diferencias en los peak de amplitud del N170 entre los grupos en la tarea de cognición social y diferencias en el rendimiento de cognición social dependiendo del tipo de filtro utilizado HSF-LSF. Conclusiones: Las alteraciones de la cognición social no son evidentes aún en la etapa CHR, sin embargo, existen diferencias entre ambos grupos en sus ERPs, lo cual podría considerarse un indicar temprano de alteraciones sensoriales en personas CH

Possible involvement of plasma antioxidant defences in training-associated decrease of platelet reponsiveness in humans

Artículo de publicación ISIHealth effects of pesticides are easily diagnosed when acute poisonings occurs, nevertheless, consequences from chronic exposure can only be observed when neuropsychiatric, neurodegenerative or oncologic pathologies appear. Therefore, early monitoring of this type of exposure is especially relevant to avoid the consequences of pathologies previously described; especially concerning workers exposed to pesticides on the job. For acute organophosphate pesticides (OPP) exposure, two biomarkers have been validated: plasma cholinesterase (ChE) and acetylcholinesterase (AChE) from erythrocytes. These enzymes become inhibited when people are exposed to high doses of organophosphate pesticides, along with clear signs and symptoms of acute poisoning; therefore, they do not serve to identify risk from chronic exposure. This study aims to assess a novel biomarker that could reflect neuropsychological deterioration associated with long-term exposure to organophosphate pesticides via the enzyme acylpeptide-hydrolase (ACPH), which has been recently identified as a direct target of action for some organophosphate compounds.The project Fondef D09I1057 was founded by FONDEF Fondo de Fomento al Desarrollo Científico y Tecnológico, CONICYT Chile (Fund for the promotion of scientific and technological development, National Commission for Scientific and Technological Research, Chile)

Estructura lingüística y teoría de la mente en trastorno del lenguaje

The concept of Theory of Mind (ToM) refers to the ability to put oneself in the other person's place and be able to interpret beliefs, desires and intentions of others. The purpose of this research was to determine the relationship between the development of the language form and the ToM in children with Mixed Specific Language Impairment (SLI) and children with typical language development. The instrument used to determinate the development of the language structure were Test de Procesos de Simplificación Fonológica (TEPROSIF-R) and Test de Comprensión Auditiva de E-Carrow (TECAL); meanwhile, to evaluate the development of the ToM were used Sally and Anne and Mentalization tests. The sample consisted on 28 children with SLI (study group) and 28 children with normal language development (control group). The results indicate that there is a relationship between the development of the ToM and the development of the structure of language in its expressive and comprehensive modality, mainly in children with Mixed SLI. From these results, it is necessary to intervene not only linguistic abilities but also those abilities related to ToM from the speech therapist tasks.El concepto de Teoría de la Mente (ToM, de su sigla en inglés) hace referencia a la capacidad de ponerse en el lugar de la otra persona y ser así capaz de interpretar creencias, deseos e intenciones de otros. El propósito de esta investigación fue determinar la relación entre el desarrollo de la forma del lenguaje y la Teoría de la mente en niños con Trastrorno Específico del Lenguaje (TEL) tipo Mixto y niños con desarrollo típico. Para evaluar el desarrollo de la estructura del lenguaje se aplicaron el Test de Procesos de Simplificación Fonológica (TEPROSIF-R) y Test de Comprensión Auditiva de E-Carrow (TECAL); en tanto, para determinar el desarrollo de la ToM se utilizan las puebas de Sally y Anne y la de Mentalización. La muestra estuvo constituida por 28 niños con TEL Mixto (grupo estudio) y 28 niños con desarrollo normal (grupo control). Los resultados indican que existe una relación entre el desarrollo de la teoría de le mente y el desarrollo de la estructura del lenguaje en su modalidad expresiva y comprensiva principalmente en los niños con TEL Mixto. A partir de estos resultados se hace necesario intervenir desde el quehacer fonoaudiológico, además de las habilidades lingüísticas, aquellas asociadas con la ToM

Association between cholinesterase's inhibition and cognitive impairment: A basis for prevention policies of environmental pollution by organophosphate and carbamate pesticides in Chile

Background: In Chile organophosphate pesticides are widely used in the production of fruits. Pesticides use is regulated for professional practice but there is no regulation regarding exposure to the general population. Objective: To relate exposure to cholinesterase's inhibitor pesticides during the spray season with neuropsychological impairment in occupationally exposed (OE) and environmentally exposed (EE) groups of people. Methods: Exposure was assessed through inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity and neuropsychological outcomes were evaluated through a large battery of tests covering general mental status, language, memory, attention, executive function, praxis and psychomotricity. Evaluations were carried out firstly in a period of no/low organophosphate pesticide use and subsequently during the spray season. All parameters were calculated as the relative change from baseline to spray season. Results: For this study in total 156 participants were recruited divided equally over participants with environmental exposures (EE) and participants with occupational exposure (OE). In the EE, BChE's enzyme activity inhibition >= 30% showed significant association with 10% or more decreased performance in several tests evaluating six of the eight cognitive areas (excepting psychomotricity and mood status); besides, for AChE inhibition in EE, the association was significant in three tests evaluating attention and one of executive function. Whereas, in OE, the inhibition of the BChE >= 30% was associated with a low performance of one attention test and for AChE the exceedance of the standard was associated with diminished performance in one test of memory and attention, respectively. The association between biomarkers of biological effect and cognitive impairment persisted among the EE group after removing confounders. No association was found between biomarkers of biological acute effect and decreased cognitive performance in the OE group. Conclusions: Increased exposure to pesticides was confirmed by increased inhibition of cholinesterase's in both exposure groups; which was associated with a diminished neuropsychological performance, mainly in the environmentally exposed study group.Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) FONDEF D09I105

Reduced neurobehavioral functioning in agricultural workers and rural inhabitants exposed to pesticides in northern Chile and its association with blood biomarkers inhibition

Background Previous biomonitoring studies have shown that people in the rural population of Coquimbo, the major agricultural area in northern Chile are being occupationally and environmentally exposed to organophosphate/carbamate (OP/CB) pesticides. Given their harmful effects, this study had two aims; first, to evaluate the effect of cumulative or chronic exposure to OP/CB pesticides on the neurobehavioral performance of agricultural workers and rural inhabitants; second, to determine if changes in the neurobehavioral performance are associated to changes in blood biomarkers of OP/CB pesticides during the spray season, when exposure is higher. Methods For the first aim, a cross sectional study of neurobehavioral performance in adult volunteers (men and women, 18-50 years-old, right-handed) was carried out in the pre-spray season. Sampling was done by convenience and a questionnaire was used to categorize participants depending on their level of chronic exposure, as either: occupationally exposed (OE,n = 87), environmentally exposed (EE,n = 81), or non-exposed controls or reference group (RG,n = 100). A neurobehavioral test battery consisting of 21 tests to measure cognitive, motor and emotional state was applied. For the second aim, neurobehavioral measures were taken a second time from EE and OE groups during the spray season, and their exposure corroborated by blood-based biomarker inhibition. Results Lower neurobehavioral performance was observed in the pre-spray evaluation of EE and OE groups compared to the non-exposed, OE being the worst performing group. Seasonal exposure impaired performance in both exposure groups on all tests except those on attention and mood. Data modeling of the basal (pre-spray) measurements showed that the level of exposure was the best predictor of performance. During spraying, inhibition of BChE activity in the EE group was the best predictor of low performance in tests measuring logical, auditory and visual memory, inhibitory control of cognitive interference, constructional and planning abilities, executive functions, and motor speed and coordination. Conclusion Long-term occupational or environmental exposure to pesticides caused impairment in neurobehavioral functioning, which worsened during the spraying season, mainly in EE. BChE inhibition was the best predictor for seasonal neurobehavioral changes in EE.chilean government through Fondo de Fomento al Desarrollo Cientifico y Tecnologico (FONDEF) D09I1057 Comisión Nacional de Investigación Científica y Tecnológica (CONICYT) CONICYT FONDECYT 312023