Influencia de la Levodopa sobre la cogniciòn en la Enfermedad e Parkinson Idiopàtica / Influence of levodopa on cognition of idiopathic Parkinson's disease

Idiopathic Parkinson's disease induces alterations both motor and cognitive. Levodopa, the treatment of choice, offers initial improvement, but causes long term important complications. It is ignored if it provokes or not a similar situation in cognitive function. Two groups of idiopathic parkinsonian patients were studied. One of them was using levodopa as a regular treatment, the other had de novo patients. A group of healthy controls was also studied. The levodopa group was evaluated when levodopa plasma concentration was maximum and when it was minimum. A cognitive battery was used in order to assess the cognitive status of all subjects. RESULTS: Significant differences between the two groups of patients and the healthy controls were found when the treated group had a maximum plasmatic concentration of levodopa. There were also significant differences when they had a minimum concentration in comparison with the healthy controls. The performances of the patients taking levodopa varied between both conditions...(AU)

Influencia de la levodopa sobre la cognición en la enfermedad de Parkinson idiopática / Influence of levodopa on cognition of idiopathic Parkinson's disease

Introducción. La enfermedad de Parkinson idiopática causa alteraciones tanto en el plano motor como en el cognitivo. La levodopa, fármaco de primera elección para su tratamiento, aunque introduce mejorías motoras inciales, provoca importantes complicaciones a largo plazo. Se desconoce si en el plano cognitivo se produce o no una situación similar. Método. Se estudiaron dos grupos de pacientes con enfermedad de Parkinson idiopática que se diferenciaban sólo por la ingestión o no de levodopa y un grupo de controles sanos. A los tres grupos se les aplicó una batería de diferentes pruebas cognitivas en las condiciones de máxima y mínima concentración plasmática del fármaco. Resultados. Se encontraron diferencias significativas entre los dos grupos de pacientes y los controles sanos cuando el grupo medicado tenía una máxima concentración plasmática de levodopa; igualmente hubo diferencias significativas cuando tenía una mínima concentración en comparación con los controles sanos. Además, las evoluciones de los pacientes medicados con levodopa variaban entre sí de una condición a otra. Conclusiones. La enfermedad de Parkinson provoca alteraciones sobre una amplia variedad de funciones cognitivas, lo que relaciona los ganglios basales con una función más general dentro de la cognición humana relativa al aprendizaje, almacenamiento y suministro a la corteza cerebral de programas motores y cognitivos. La levodopa ejerce un efecto diferente sobre distintas funciones cognitivas, pudiendo incluso fluctuar los beneficios que provoca entre los períodos de máxima y mínima concentración plasmática del fármaco. En algunas funciones aisladas puede causar empeoramiento cuando su concentración es máxima. Este hecho llama la atención acerca de que el uso prolongado de la levodopa puede introducir fluctuaciones más drásticas en el funcionamiento cognitivo general del paciente (AU)

[Influence of levodopa on cognition of idiopathic Parkinson's disease]. / Influencia de la levodopa sobre la cognición en la enfermedad de Parkinson idiopática.

INTRODUCTION: Idiopathic Parkinson's disease induces alterations both motor and cognitive. Levodopa, the treatment of choice, offers initial improvement, but causes long term important complications. It is ignored if it provokes or not a similar situation in cognitive function. METHOD: Two groups of idiopathic parkinsonian patients were studied. One of them was using levodopa as a regular treatment, the other had de novo patients. A group of healthy controls was also studied. The levodopa group was evaluated when levodopa plasma concentration was maximum and when it was minimum. A cognitive battery was used in order to assess the cognitive status of all subjects. RESULTS: Significant differences between the two groups of patients and the healthy controls were found when the treated group had a maximum plasmatic concentration of levodopa. There were also significant differences when they had a minimum concentration in comparison with the healthy controls. The performances of the patients taking levodopa varied between both conditions. CONCLUSIONS: Parkinson's disease provokes a wide variety of cognitive alterations, therefore basal ganglia can be related to a more general function as learning and storing cognitive and motor programs. Levodopa influences in a different way different cognitive functions differently and its influence varies between highest and lowest plasmatic concentrations periods. These results allow us to draw important conclusions about the cognitive alterations caused by the natural course of Parkinson's disease, the introduction of treatment with levodopa and the relationship between basal ganglia and human cognition.

[Event-related potentials and the diagnosis of short-term verbal memory disorders in cerebrovascular disease]. / Potenciales relacionados con eventos y diagnóstico de las alteraciones de memoria verbal a corto plazo en la enfermedad cerebrovascular.

INTRODUCTION: Cerebrovascular disease can cause different memory disorders depending on the area of the brain involved. More specifically, ischemic lesions in the frontal region can be associated to short-term verbal memory disorders. PATIENTS AND METHODS: Two groups of subjects were studied, 10 of whom were patients who presented a frontal cerebral infarction and 10 healthy controls. They were administered a memory task involving word recognition. While they were performing the task the electrical activity of their brains was recorded in order to examine event-related potentials (ERP). RESULTS: The patients' performance of the task was poorer than that of the healthy control subjects. Likewise, while the latter displayed a predominantly frontal distribution of ERPs, in the patients the frontal activity diminished and was seen to be chiefly temporoparietooccipital. CONCLUSIONS: These findings allow important conclusions to be drawn about the characteristics of the memory disorder presented by these patients.

Potenciales relacionados con eventos y diagnóstico de las alteraciones de memoria verbal a corto plazo en la enfermedad cerebrovascular / Event-related potentials and the diagnosis of short-term verbal memory disorders in cerebrovascular disease

Cerebrovascular disease can cause different memory disorders depending on the area of the brain involved. More specifically, ischemic lesions in the frontal region can be associated to short-term verbal memory disorders. Two groups of subjects were studied, 10 of whom were patients who presented a frontal cerebral infarction and 10 healthy controls. They were administered a memory task involving word recognition. While they were performing the task the electrical activity of their brains was recorded in order to examine event-related potentials (ERP). The patients' performance of the task was poorer than that of the healthy control subjects. Likewise, while the latter displayed a predominantly frontal distribution of ERPs, in the patients the frontal activity diminished and was seen to be chiefly temporoparietooccipital. These findings allow important conclusions to be drawn about the characteristics of the memory disorder presented by these patients(AU)

Potenciales relacionados con eventos y diagnóstico de las alteraciones de la memoria verbal a corto plazo en la enfermedad cerebrovascular / Event-related potentials and the diagnosis of short-term verbal memory disorders in cerebrovascular disease

Introducción. La enfermedad cerebrovascular puede causar alteraciones de la memoria diferentes en función del área cerebral afectada. Las lesiones isquémicas en la región frontal pueden asociarse a alteraciones de la memoria verbal a corto plazo, específicamente. Pacientes y métodos. Se estudiaron dos grupos de sujetos, 10 de ellos pacientes que presentaban un infarto cerebral frontal, y 10 controles sanos. Se les aplicó una tarea de memoria de reconocimiento de palabras. Durante su realización se recogió la actividad eléctrica cerebral para el registro de los potenciales relacionados con eventos (PRE). Resultados. Los pacientes tuvieron una ejecución deficitaria en la tarea en comparación con los controles sanos. Igualmente, mientras éstos mostraban una distribución predominantemente frontal de los PRE, en los pacientes la activación frontal disminuía y era de preferencia temporoparietoccipital. Conclusiones. Estos resultados permiten extraer importantes conclusiones sobre las características de la alteración de la memoria presentada por los pacientes (AU)

Introduction. Cerebrovascular disease can cause different memory disorders depending on the area of the brain involved. More specifically, ischemic lesions in the frontal region can be associated to short-term verbal memory disorders. Patients and methods. Two groups of subjects were studied, 10 of whom were patients who presented a frontal cerebral infarction and 10 healthy controls. They were administered a memory task involving word recognition. While they were performing the task the electrical activity of their brains was recorded in order to examine event-related potentials (ERP). Results. The patients’ performance of the task was poorer than that of the healthy control subjects. Likewise, while the latter displayed a predominantly frontal distribution of ERPs, in the patients the frontal activity diminished and was seen to be chiefly temporoparietooccipital. Conclusions. These findings allow important conclusions to be drawn about the characteristics of the memory disorder presented by these patients (AU)

[Cognitive diagnosis of cerebrovascular disease by event related potentials: anatomical sources that generate P300]. / Diagnóstico cognitivo en la enfermedad cerebrovascular mediante potenciales relacionados con eventos: fuentes anatómicas generadoras de la P300.

INTRODUCTION: Cerebrovascular disease causes different cognitive alterations. There is a need to develop tools that are capable of diagnosing them. One of them could be event related potentials. These provide an indicator of cognitive processing in real time. PATIENTS AND METHODS: A study was conducted of 10 patients with cerebral infarction in the frontal region and 10 paired healthy controls. Evaluation of the patients was performed a week after the stroke. A continuous performance test was applied to both groups together with the recording of the electrical activity in the brain in order to obtain the P300 component. The results were submitted to the non-parametric Student's t test, and the Bayesian model averaging method (BMAM) was employed to calculate the sources generating the electrical activity recorded on the electroencephalogram. RESULTS: Patients displayed significantly poorer performances compared to the healthy controls in the attention test. The BMAM showed that the P300 component was related to the right hand temporal structures in healthy controls, whereas the left temporoparietal regions were also involved in the patients. CONCLUSIONS: These findings indicate the existence of subclinical disorders affecting sustained attention and that they can only be detected by very sensitive tools; furthermore, they also have implications for the brain circuits regulating sustained attention and the P300 component.

Diagnóstico cognitivo en la enfermedad cerebrovascular mediante potenciales relacionados con eventos: fuentes anatómicas generadoras de la P300 / Cognitive diagnosis of cerebrovascular disease by event-related potentials: anatomical sources that generate p300

Introducción. La enfermedad cerebrovascular causa alteraciones cognitivas disímiles. Es preciso desarrollar herramientas capaces de diagnosticarlas, y una de ellas podría ser los potenciales relacionados con eventos. Éstos brindan un indicador en tiempo real del procesamiento cognitivo. Pacientes y métodos. Se estudiaron 10 pacientes con infarto cerebral en la región frontal y 10 controles sanos pareados. La evaluación de los pacientes se realizó una semana después de presentar el infarto. A ambos grupos se les aplicó un test de ejecución continua asociado al registro de la actividad eléctrica cerebral para la obtención del componente P300. Los resultados obtenidos se sometieron a la prueba no paramétrica t de Student, y el electroencefalograma, al método de promediación de modelos bayesianos (MPMB) para el cálculo de las fuentes generadoras de la actividad eléctrica registrada. Resultados. Los pacientes tuvieron ejecuciones significativamente más pobres que los controles sanos en la prueba de atención. El MPMB mostró que el componente P300 se relaciona con las estructuras temporales derechas en los controles sanos, mientras que en los pacientes se suman las zonas temporoparietales izquierdas. Conclusiones. Estos resultados indican la existencia de alteraciones subclínicas de la atención sostenida, y que sólo herramientas más sensibles pueden detectarlas; además, tienen implicaciones para los circuitos cerebrales reguladores de la atención sostenida y del componente P300 (AU)

Introduction. Cerebrovascular disease causes different cognitive alterations. There is a need to develop tools that are capable of diagnosing them. One of them could be event-related potentials. These provide an indicator of cognitive processing in real time. Patients and methods. A study was conducted of 10 patients with cerebral infarction in the frontal region and 10 paired healthy controls. Evaluation of the patients was performed a week after the stroke. A continuous performance test was applied to both groups together with the recording of the electrical activity in the brain in order to obtain the P300 component. The results were submitted to the non-parametric Student’s t test, and the Bayesian model averaging method (BMAM) was employed to calculate the sources generating the electrical activity recorded on the electroencephalogram. Results. Patients displayed significantly poorer performances compared to the healthy controls in the attention test. The BMAM showed that the P300 component was related to the right-hand temporal structures in healthy controls, whereas the left temporoparietal regions were also involved in the patients. Conclusions. These findings indicate the existence of subclinical disorders affecting sustained attention and that they can only be detected by very sensitive tools; furthermore, they also have implications for the brain circuits regulating sustained attention and the P300 component (AU)

[Specific alterations in attention in the early stages of Parkinson's disease]. / Alteraciones específicas de la atención en estadios tempranos de la Enfermedad de Parkinson.

INTRODUCTION: The cognitive disorders presented by patients with Parkinson s disease (PD) have drawn attention to the role played by the basal ganglia in cognition. It has been suggested that through a system of cortico subcortical circuits they monitor the work done by the frontal regions by guiding the anterior and posterior attentional systems, whose functioning is necessary for the so called executive functions to be carried out. PATIENTS AND METHODS: We studied 10 patients with PD in developmental stages I and II according to the scale of Hoehn and Yahr, and 10 healthy paired controls. All of them were administered a test for simple sustained attention, complex sustained attention and attentional shift. RESULTS: In the simple sustained attention task there were no significant differences between groups. In the complex sustained attention test the patients committed more mistakes, and in the attentional shift task they committed more omissions and there was a significant increase in reaction time. CONCLUSIONS: Even in the early stages of the disease, patients suffering from Parkinson present cognitive disorders. These are concentrated in the detection and evaluation of new information, in the capability to shift attention between different spatial regions in a flexible manner and in choosing, inhibiting and activating motor programmes. In order to detect these alterations more sensitive and complex tests must be used.

Alteraciones específicas de la atención en estadios tempranos de la enfermedad de Parkinson / Specific alterations in attention in the early stages of Parkinson´s disease

Introducción. Los trastornos cognitivos que presentan los pacientes con enfermedad de Parkinson (EP) han llamado la atención sobre la función de los ganglios basales en la cognición. Se ha propuesto que monitorizan el trabajo de las regiones frontales mediante un sistema de circuitos cortico subcorticales, al guiar a los sistemas atencionales anterior y posterior, cuyo funcionamiento se necesita para el desarrollo de las llamadas funciones ejecutivas. Pacientes y métodos. Se estudiaron 10 pacientes con EP en estadios evolutivos I y II según la escala de Hoehn yYahr y 10 controles sanos pareados. A todos se les aplicó una prueba de atención sostenida simple, atención sostenida compleja y de cambio atencional. Resultados. En la prueba de atención sostenida simple no hubo diferencias significativas entre los grupos. En la de atención sostenida compleja los pacientes cometieron una mayor cantidad de errores, y en la de cambio atencional cometieron más omisiones y aumentaron significativamente su tiempo de reacción. Conclusiones. Los pacientes parkinsonianos que se encuentran en estadios tempranos de la enfermedad presentan alteraciones cognitivas. Éstas se concentran en la detección y evaluación de nueva información, en la posibilidad de cambiar de manera flexible la atención entre regiones espaciales diferentes y en elegir, inhibir y activar programas motores. Para detectar estas alteraciones se precisa de pruebas más sensibles y complejas (AU)