Plasticidad Neuronal

Plasticidad neuronal funcional
S. Hernández-Muela, F. Mulas, L. Mattos
FUNCTIONAL NEURONAL PLASTICITY Summary. Introduction. Thanks to the contributions made by neuroscientific research and the clinical evidence regarding the functional recovery of the central nervous system in the different motor, cognitive, linguistic and sensory spheres, we now know more about how the brain is built and itsmodifications. This recovery is possible due to the plasticity of the brain, its capacity to reorganise itself and to modify functions in order to adapt to both external and internal changes. This capacity is inherent to brain cells and allows cortical circuits to be repaired, integrates other cortical areas to carry out modified functions and responds to different disorders. It depends ongenetic, neuronal and neurochemical factors and its limits can be manipulated through clinical and pharmacological intervention. Development. The brain’s capacity to adapt itself to changes is crucial in the development of the nervous system and has important repercussions on learning. The neuroanatomical, neurochemical and functional changes that take place during the reorganisation made possible byplasticity will facilitate the recovery-acquisition of the functions involved (adaptive plasticity) and may hinder the development of others (maladaptive plasticity). This variability of the possible responses is related to the chronology of the lesion, the site that is affected, the state of the substrata that can take on the function and the type of function that is altered. The mechanismsresponsible for facilitating this plasticity are different at any given time (fast and late plasticity), depending on the function that is altered, with expansion of the somatotopic representations in the motor cortex adjacent to the damage, interhemispherical transfer of language or crossed plasticity in the auditory or visual function. The neuropsychological pathology can appear linked to the lesion orsecondary to a maladaptive plasticity. Conclusions. Advancing in our knowledge of the intrinsic mechanisms of brain plasticity and synaptic regulation will lead us to understand the recovery of damaged or lost functions in the brains of children with special needs, and thus allow us to implement favourable clinical and pharmacological interventions. [REV NEUROL 2004; 38 (Supl 1): S58-68] Keywords. Brain plasticity. Crossed plasticity. Early attention. Fast plasticity. Functional recovery. Late plasticity. Maladaptive plasticity. Neuropsychological pathology.

INTRODUCCIÓN: ENTENDIENDO LA ATENCIÓN PRECOZ EN NIÑOS CON NECESIDADES ESPECIALES La atención temprana es un término general que describe los programas de intervención terapéutica y educativa, a distintos niveles, dirigidos a niñosde 0 a 6 años con problemas en su desarrollo, sus familias y entorno, destinados a prevenir o minimizar las posibles alteraciones o deficiencias ya existentes [1]. Surge en sus orígenes de la evidencia de que, a través de la generación de un ambiente rico en estímulos de diverso tipo, podemos intervenir positivamente en la adquisición de funciones o capacidades que se han visto mermadas porproblemas acaecidos a lo largo del desarrollo o en problemas surgidos a lo largo de la maduración de las mismas. Desde la neurología, el Dr. Katona (Instituto Pediátrico de Budapest) fundamenta lo que denomina ‘neurohabilitación’ o ‘rehabilitación temprana’ en la plasticidad del cerebro en los primeros meses de vida, en base a la activación y aprovechamiento funcional de todas las estructuras delsistema nervioso central (SNC), que conserven su funcionalidad normal e incluso de aquellas que presentan funciones incompletas en relación con el daño cerebral [2]. Los estímulos a utilizar (input) son diversos, y en la generación de las respuestas (output) se consigue establecer o reforzar circuitos neuronales que facilitan la adquisición de funciones cerebrales dificultadas por diversas lesiones o...