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TIP. Revista especializada en ciencias químico-biológicas
Print version ISSN 1405-888X
TIP vol.11 n.1 Ciudad de México Jun. 2008
Artículos de revisión
Codificación de estados funcionales en redes neuronales biológicas
1Depto. de Biofisica, Instituto de Fisiología Celular, UNAM. Ciudad Universitaria, CP. 04510, México, D.F.
Un tema central para las neurociencias consiste en descifrar la forma en la cual las redes neuronales biológicas procesan la información y guardan memorias. En 1949 Donald Hebb propuso que la actividad reverberante de pequeños circuitos neuronales llamados "ensambles" funcionaría como el sustrato sobre el cual se construyen las rutas de la memoria. Sin embargo, para poder almacenar cualquier tipo de información compleja, los ensambles neuronales deberían tener la habilidad de organizarse en jerarquías, es decir, pequeñas subrutinas que componen procedimientos más elaborados. Nuestros experimentos muestran que los circuitos con estas capacidades pueden encontrarse en pequeños pedazos de cerebro aislado in vitro y estudiarse con detalle. De esta manera, el cerebro como cualquier sistema puede ser entendido y estudiado de acuerdo con sus elementos básicos y sus reglas de composición; permitiéndonos entender desde la forma en la cual nos comunicamos hasta los hábitos que determinan nuestra vida cotidiana. Los hallazgos experimentales aquí descritos podrían sentar las bases para entender tanto los estados cerebrales normales como los patológicos, con lo cual será posible proponer soluciones para distintas enfermedades neurodegenerativas que tienen un gran impacto en la sociedad.
Palabras Clave: Código neuronal; ensambles neuronales; propiedades de composición; propiedades intrínsecas y extrínsecas; redes neuronales
A central issue to Neuroscience is the knowledge of how biological neural networks process the information and store memories. In 1949 Donald Hebb proposed reverberant "cell assemblies" as the substrate for memory storage. However, in order to store any kind of composed knowledge cell assemblies must have the ability to form hierarchies: subcircuits composing larger circuits. Our experiments show that circuits with these properties can be found in small pieces of brain tissue isolated in vitro and thus amenable to be studied in full detail. Hence, the brain as any system can be understood in terms of simpler parts and their compositional rules, allowing us to understand our communication, motor actions and habits that represent our life style. The findings here described could open the possibility to better understand normal and pathological brain functional states, to be able to propose original solutions for neurodegenerative diseases that drastically affect our society.
Key Words: Neural coding; cell assemblies; compositionality; intrinsic and extrinsic properties; neural networks
Agradecimientos
Este trabajo está apoyado por: IMPULSA-UNAM, DGAPA-UNAM 201603, CONACyT 49484.
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Recibido: 03 de Mayo de 2008; Aprobado: 18 de Junio de 2008
Este es un artículo publicado en acceso abierto bajo una licencia Creative Commons
