R epresentation O f S timuli A s N eural A ctivity

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Representation Of Stimuli As Neural Activity ROSANA Project UCM-UAM-FrI-UPo-UEs

description

R epresentation O f S timuli A s N eural A ctivity. ROSANA Project. UCM-UAM-FrI-UPo-UEs. “ Perception ” ⇩ “ Internal Representation ” of the external world. Understand the fundaments of perception. Determine the principles of coding of sensory stimuli. - PowerPoint PPT Presentation

Transcript of R epresentation O f S timuli A s N eural A ctivity

Page 1: R epresentation O f S timuli A s N eural A ctivity

Representation Of Stimuli As Neural Activity

ROSANA Project

UCM-UAM-FrI-UPo-UEs

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“Perception”⇩

“Internal Representation” of the external world

we will be able to reproduce the same spatiotemporal pattern of activity

Understand the fundaments of perception

Determine the principles of coding of sensory stimuli

Interactions sensory inputs - activity of CNS neurons

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Lemniscal somatosensory system

10.000

500.000

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Our Experiment

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State of the project (started May 2002)

•We set-up a complete electrophysiology lab

•We implanted sieve microelectrodes in the peripheral nerve of rats and cats

•We obtained functional regeneration of the sensory nerves

•We recorded the electrical activity of the regenerated nerves•We recorded electrical activity simultaneously from the regenerated nerve and from neurons in the CNS•We developed mathematical and computational models of oscillating neurons•We deveoped specific microstimulators to control the stimulation

•We are developing new microstimulators to control the stimulation•We are developing new mathematical and computational models

•We are developing new microelectrodes

•We are setting-up the 140 simultaneous recording procedure

•We are setting-up the new data analysis techniques

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Problems to be solved

1. If artificial sensors are to be directly connected to the nerve(s), only a very low number of fibers can be interfaced

2. Interfacing of artificial sensors to a sensory nerve will submit to each axon information concerning different sensory submodalities in an entirely unpredictable fashion