Using Virtual Reality to Study Spatial Mapping and Threat Learning.

Using spatial mapping processes to learn about threat and safety in an environment is crucial for survival. Research using conditioning paradigms has explored the effects of state (transient arousal) and trait anxiety (anxiety as an aspect of personality) on threat learning and acquisition. However, results are mixed, and little is known regarding why some individuals do not learn to discriminate between threat and safety during contextual conditioning. We used a virtual reality (VR) contextual threat conditioning paradigm to elucidate the effects of state and trait anxiety on contextual threat learning. 70 healthy participants (46 female) navigated and "picked" flowers in a VR environment. Flowers picked in the dangerous zone (half of the environment) were paired with an electric shock (or "bee sting") to the hand; flowers picked in the safe zone were never paired with a shock. Participants also collected and returned neutral objects as a measure of spatial memory. Galvanic skin response (GSR) was measured throughout the task and anxiety was assessed via the State Trait Anxiety Inventory (STAI). Participants were categorized as learners if they correctly identified the two zones after the task. Non-learners, compared to learners, performed significantly worse during the spatial memory task and demonstrated significantly higher state anxiety scores and GSR levels throughout the task. Learners showed higher skin conductance response (SCR) in the dangerous zone compared to the safe zone while non-learners showed no SCR differences between zones. These results indicate that state anxiety may impair spatial mapping, disrupting contextual threat learning.

Revisión de las pruebas cognitivas breves para pacientes con sospecha de demencia / Review of brief cognitive tests for patients with suspected dementia

RESUMEN NTRODUCCIÓN: Para ser útiles, las pruebas cognitivas breves (PCB) deben ser rápidas, sensibles, fáciles de realizar y no necesitar de un gran entrenamiento para hacerlo. Las pruebas cognitivas breves comúnmente utilizadas incluyen el Mini Examen del Estado Mental (MMSE) y la Evaluación Cognitiva de Montreal (MoCA). OBJETIVO: Brindar una descripción de las PCB disponibles y sus propiedades psicométricas para la detección de la demencia. MÉTODOS: Revisión narrativa RESULTADOS: El MMSE le otorga un gran peso a la orientación, la memoria, la visuo-espacialidad y el lenguaje, y, en consecuencia, puede ser sensible a los déficits cognitivos encontrados en la demencia tipo Alzheimer. MoCA es una prueba breve más compleja que evalúa una gama más amplia de dominios cognitivos, especialmente funciones ejecutivas, proporcionando una mayor sensibilidad para detectar el deterioro cognitivo leve y otros tipos de demencia, no solo la demencia tipo Alzheimer. CONCLUSIONES: Las PCB son parte del arsenal necesario para ayudar a confirmar la sospecha de la demencia. La escolaridad tiene un impacto importante en el desempeño de las PCB y puede sesgar la interpretación de los resultados obtenidos.

ABSTRACT INTRODUCTION: To be useful, Brief Cognitive Tests (BCTs) must be fast, sensitive, easy to perform, and not require extensive training to do so. Commonly used brief cognitive tests include the Mini Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA). OBJECTIVE: To provide a description of the available BCTs and their psychometric properties for the detection of dementia. METHODS: Narrative review RESULTS: The MMSE places great weight on orientation, memory, visuospatiality, and language, and, consequently, may be sensitive to the cognitive deficits found in Alzheimer's dementia. MoCA is a more complex brief test that assesses a broader range of cognitive domains, especially executive functions, providing greater sensitivity for detecting mild cognitive impairment and other types of dementia, not just Alzheimer's dementia. CONCLUSIONS: BCTs are part of the arsenal needed to help confirm suspected dementia. Schooling has an important impact on the performance of BCTs and can bias the interpretation of the results obtained.

Síndrome de la arteria mesentérica superior: abordaje quirúrgico. Reporte de caso / Superior mesenteric artery syndrome: surgical approach, case report

El síndrome de arteria mesentérica superior (SAMS), causa infrecuente de obstrucción intestinal proximal; ocurre por compresión externa de la tercera porción duodenal por la arteria mesentérica superior debido a la formación de un ángulo inadecuado de la unión aortomesentérica. Incidencia de 0.013% - 0.3. Se presenta caso de paciente masculino de 27 años con diagnóstico de SAMS, historia de pérdida de peso, dolor postprandial recurrente, náuseas, vómitos de contenido biliar de un año de evolución. Paciente se ingresa al servicio de emergencia de Cirugía de Adultos del Hospital Roosevelt, Guatemala, donde se programa y realiza abordaje con técnica de Strong, además de la realización de duodeno-yeyuno anastomosis. Evoluciona satisfactoriamente por lo que se concluye que la técnica de Strong aunada a la realización de duodeno-yeyuno anastomosis son herramientas más efectivas como abordaje quirúrgico del síndrome de arteria mesentérica superior. (AU)

The superior mesenteric artery syndrome (SAMS), a rare cause of proximal intestinal obstruction; It occurs by external compression of the third duodenal portion by the superior mesenteric artery due to the formation of an inappropriate angle of the aortomesenteric junction. Incidence of 0.013% - 0.3. A case of a 27-year-old male patient is presented with a diagnosis of SAMS, history of weight loss, recurrent postprandial pain, nausea, vomiting of bile content of one year of evolution. Patient is admitted to the emergency service of Adult Surgery of the Roosevelt Hospital, Guatemala, where an approach with Strong's technique is programmed and performed in addition to the duodenum-jejunum anastomosis, it evolves satisfactorily, which is why it is concluded that the Strong's technique combined duodenum-jejunum anastomosis are more effective tools as a surgical approach to superior mesenteric artery syndrome. (AU)