Скачать или смотреть Evolved Machines - Brief presentation of 2d object to Synthetic Visual Cortex

A synthetic visual cortex.
Paul A. Rhodes - Evolved Machines - Mountain View, CA.

The neurons in each layer of this simulated visual cortex wire themselves during sensory experience, creating a synthetic neural fabric that self-organizes to represent visual information. The "retinal" layer consists of 4 64x64 arrays of distinct spatiotemporal filters, a subset of the over 17 spatiotemporal filter types found in mammalian retina. A visual object (a simple diamond shape) activates a subset of these units, with the cell bodies and axons firing shaded yellow. Retinal axons in turn directly activate (the thalamus is omitted in this simplification) the first layer of a "visual cortex", which includes both inhibitory and excitatory cell types interwoven. The excitatory cells and their axons firing in the first layer of this system are colored orange, and in turn project to the next layer, causing the firing pyramidal cells there (in pink). The dendrites and axons of these cells and their connections have been grown both during development and then refined during sensory experience to create the neural fabric shown here, in a manner inspired by the mechanisms observed in neurobiological circuit development. During several million timesteps of exposure to simulated visual input the axonal connections themselves continually reorganize according to an evolved set of local rules. The wiring resulting from this process gives rise to neurons that begin to show the visual response properties, including so-called "complex cell" receptive fields, observed in the mammalian visual cortex.