Whole Brain Emulation: Looking At Progress On C. elgans

Be­ing able to treat the pat­tern of some­one’s brain as soft­ware to be run on a com­puter, per­haps in par­allel or at a large speedup, would have a huge im­pact, both so­cially and eco­nom­i­cally. Robin Han­son thinks it is the most likely route to ar­tifi­cial in­tel­li­gence. An­ders Sand­berg and Nick Bostrom of the Fu­ture Of Hu­man­ity In­sti­tute cre­ated out a roadmap for whole brain em­u­la­tion in 2008, which cov­ers a huge amount of re­search in this di­rec­tion, com­bined with some scale anal­y­sis of the difficulty of var­i­ous tasks.

Be­cause the hu­man brain is so large, and we are so far from hav­ing the tech­ni­cal ca­pac­ity to scan or em­u­late it, it’s difficult to eval­u­ate progress. Some other or­ganisms, how­ever, have much smaller brains: the ne­ma­tode C. el­e­gans has only 302 cells in its en­tire ner­vous sys­tem. It is ex­tremely well stud­ied and well un­der­stood, hav­ing gone through heavy use as a re­search an­i­mal for decades. Since at least 1986 we’ve known the full neu­ral con­nec­tivity of C. el­e­gans, some­thing that would take decades and a huge amount of work to get for hu­mans. At 302 neu­rons, simu­la­tion has been within our com­pu­ta­tional ca­pac­ity for at least that long. With 25 years to work on it, shouldn’t we be able to ‘up­load’ a ne­ma­tode by now?

Read­ing through the re­search, there’s been some work on mod­el­ing sub­sys­tems and com­po­nents, but I only find three pro­jects that have tried to in­te­grate this re­search into a com­plete simu­la­tion: the Univer­sity of Ore­gon’s Ne­maSys (~1997), the Perfect C. el­e­gans Pro­ject (~1998), and Hiroshima Univer­sity’s Vir­tual C. Ele­gans pro­ject (~2004). The sec­ond two don’t have web pages, but they did put out pa­pers: [1], [2], [3].

Another way to look at this is to list the re­searchers who seem to have been in­volved with C. el­e­gans em­u­la­tion. I find:

  • Hiroaki Ki­tano, Sony [1]

  • Shugo Hama­hashi, Keio Univer­sity [1]

  • Sean Luke, Univer­sity of Mary­land [1]

  • Michiyo Suzuki, Hiroshima Univer­sity [2][3]

  • Takeshi Goto, Hiroshima Univeristy [2]

  • Toshio Tsuji, Hiroshima Univeristy [2][3]

  • Hisao Oh­take, Hiroshima Univeristy [2]

  • Thomas Fer­ree, Univer­sity of Ore­gon [4][5][6][7]

  • Ben Mar­cotte, Univer­sity of Ore­gon [5]

  • Sean Lock­ery, Univer­sity of Ore­gon [4][5][6][7]

  • Thomas Morse, Univer­sity of Ore­gon [4]

  • Stephen Wicks, Univer­sity of Bri­tish Columbia [8]

  • Chris Roehrig, Univer­sity of Bri­tish Columbia [8]

  • Catharine Rankin, Univer­sity of Bri­tish Columbia [8]

  • An­gelo Can­gelosi, Rome In­sti­tu­ite of Psy­chol­ogy [9]

  • Domenico Parisi, Rome In­sti­tu­ite of Psy­chol­ogy [9]

This seems like a re­search area where you have mul­ti­ple groups work­ing at differ­ent uni­ver­si­ties, try­ing for a while, and then mov­ing on. None of the simu­la­tion pro­jects have got­ten very far: their em­u­la­tions are not com­plete and have some pieces filled in by guess­work, ge­netic al­gorithms, or other ar­tifi­cial sources. I was op­ti­mistic about find­ing suc­cess­ful simu­la­tion pro­jects be­fore I started try­ing to find one, but now that I haven’t, my es­ti­mate of how hard whole brain em­u­la­tion would be has gone up sig­nifi­cantly. While I wouldn’t say whole brain em­u­la­tion could never hap­pen, this looks to me like it is a very long way out, prob­a­bly hun­dreds of years.

Note: I later re­or­ga­nized this into a blog post, in­cor­po­rat­ing some feed back from these com­ments.


[1] The Perfect C. el­e­gans Pro­ject: An Ini­tial Re­port (1998)

[2] A Dy­namic Body Model of the Ne­ma­tode C. el­e­gans With Neu­ral Os­cilla­tors (2005)

[3] A model of mo­tor con­trol of the ne­ma­tode C. el­e­gans with neu­ronal cir­cuits (2005)

[4] Ro­bust spa­cial nav­i­ga­tion in a robot in­spired by C. el­e­gans (1998)

[5] Neu­ral net­work mod­els of chemo­taxis in the ne­ma­tode C. el­e­gans (1997)

[6] Che­mo­taxis con­trol by lin­ear re­cur­rent net­works (1998)

[7] Com­pu­ta­tional rules for chemo­taxis in the ne­ma­tode C. el­e­gans (1999)

[8] A Dy­namic Net­work Si­mu­la­tion of the Ne­ma­tode Tap With­drawl Cir­cuit: Pre­dic­tions Con­cern­ing Sy­nap­tic Func­tion Us­ing Be­hav­ioral Cri­te­ria (1996)

[9] A Neu­ral Net­work Model of Caenorhab­di­tis Ele­gans: The Cir­cuit of Touch Sen­si­tivity (1997)