A conversation with the creators of the world’s largest functioning model of the human brain

Last night, the group of researchers responsible for the creation of the SPAUN project – that just published the first large scale model of a functioning brain to produce complex behaviours began an “ask me anything” (AMA) on Reddit. The scientists offer frank answers to questions ranging from technical queries from other scientists to enquiries from layman on topics spanning from the singularity to “would you have relations with a fully aware functional AI in a robots [sic] body that has realistic skin and genitals?”.

“Can you give us as layman of a description as you can of how this thing actually works? How does your software actually emulate biological systems? What is the architecture of the software like at a high level? What does the data look like that makes up the ‘memory’?

(Xuan says): Spaun is comprised of different modules (parts of the brain if you will), that do different things. There is a vision module, a motor module, memory, and a decision making module.

The basic run-down of how it works is: It gets visual input, processes said visual input, and based of the visual input, decides what to do with it. It could put it in memory, or change it in some way, or move the information from one part of the brain to another, and so forth. By following a set of appropriate actions it can answer basic tasks:

e.g. – get visual input – store in memory – take item in memory, add 1, put back in memory – do this 3 times – send memory to output

The cool thing about spaun is that it is simulated entirely with spiking neurons, the basic processing units in the brain.

You can find a picture of the high-level architecture of spaun here.

The stuff in the memory modules of spaun are points in a high dimensional space. If you think about a point on a 2D plane, then on a 3D plane. Now extend that to a 512D hyperspace. It’s hard to imagine. =)”

For a brief background on SPAUN check out IEEE Spectrum, for a more detailed account check out Ed Yong’s report over at Nature News or read more on the researchers’ website. The relevant paper is behind a paywall but at the moment you still can grab a copy over at Google Scholar. The researchers are no longer live at Ask Redditt but have said they will continue to check back with the aim of answering all questions!

Reference:

Eliasmith, C., Stewart, T., Choo, X., Bekolay, T., DeWolf, T., Tang, Y., & Rasmussen, D. (2012). A Large-Scale Model of the Functioning Brain Science, 338 (6111), 1202-1205 DOI: 10.1126/science.1225266