Temporal processing in Drosophila melanogaster

Descripción del proyecto

Procesamiento temporal de la información en el cerebro

El cerebro emplea patrones espaciales y temporales de la actividad eléctrica para procesar la información. Los patrones espaciales están determinados por la anatomía del cerebro, pero aún no se conocen del todo los procesos que rigen la dinámica temporal de la actividad a escala de milisegundos o minutos. En el proyecto TEMPRODROME, financiado por el Consejo Europeo de Investigación, se examinarán esos procesos utilizando la mosca del vinagre, «Drosophila melanogaster», como organismo modelo. Los investigadores utilizarán registros de parche de membrana («patch-clamp» en inglés) «in vivo», imagenología funcional y experimentos conductuales para estudiar cómo el cerebro filtra y almacena información sobre estímulos visuales a lo largo del tiempo; cómo el cerebro recopila información sobre el movimiento visual, y cómo el cerebro mantiene un registro de la distancia recorrida a lo largo del tiempo durante el movimiento.

Objetivo

All information processing in nervous systems relies on spatial and temporal patterns of neural activity. While spatial patterns are dictated by neuroanatomy, the mechanisms that give rise to temporal activity patterns are diverse. They range from fast voltage dynamics of single neurons at one end of the spectrum to slow transcriptional and structural changes at the other, but the rules that shape signals at timescales in between milliseconds and minutes are poorly understood. The proposed research aims to uncover mechanisms of temporal information processing at these intermediate timescales, at which temporal patterns are thought to emerge from recurrently connected circuits. Detailed insight into the function of these circuits has been limited by the large number of circuit elements, by the lack of knowledge about their connectivity, and by the impracticability of recording from all circuit elements under naturalistic conditions. In Drosophila melanogaster, these limitations no longer apply. The comparatively low number of neurons, their well-mapped connectivity, and our ability to record and control their activities make mechanistic concepts testable. We will focus on three processes in the brain of Drosophila that unfold over three timescales ranging from milliseconds to minutes: 1) temporal filtering in the motion vision system, 2) sequential sampling of motion information in the lead-up to a perceptual judgement, and 3) temporal integration of distance during locomotion. Patch clamp experiments in the smallest of invertebrate neurons in vivo will allow us to record activity at the highest temporal resolution. We will combine this technique with behavioural, genetic, and imaging experiments to test the roles of individual neurons, their biophysical properties, and their synaptic connections in processing signals at intermediate timescales. The proposed experiments will further our understanding of motion vision, perceptual decision-making, and path integration.