March 3, 2013

On worms, cities, brains, and behavior

These features are being cross-posted from my micro-blog, Tumbld Thoughts.

Here is a link to an excellent review in the blog Neuroanthropology [1] on recent work by Cornelia Bargmann [2] using C. elegans [3] as a model for uncovering the "building blocks" of sensorimotor behavior -- and its relationship with experience [4]. This work advances the idea that neuropeptides (e.g. oxytocin and vasopressin) organize behavioral complexity in a manner similar to how Hox genes organize phenotypic development [5].

This is a brand new paper (as of 2/28/2013) from the Nicolelis Lab at Duke on brain-to-brain interfaces (BTBI). BTBIs [6] are similar to BCI/BMI technology [7], but instead of neural signals driving a computer interface or machine, they are used to stimulate the brain of a conspecific (in this case, another rat on another continent [8], as shown in above image and described in the paper).

Finally, here is an image and linkfest related to the pre-release hype surrounding SimCity5. Unique features of the updated release include the use of tilt-shift photography and the Glassbox game engine. The Sims (humanoid agents) are also a bit more human-like.

So to provide context, here are four Wired Science blog posts by Sam Arbesman. The first post [9] is the connection between LEGO and SimCity as modeling tools (e.g. modeling cities at small scales). The second and third posts [10, 11] involve understanding the scale of cities in the context of their importance and how Kolmogorov complexity [12] can characterize this scalar relationship.

The fourth post describes a paper by Mark Changizi [13] in which the number and frequency of distinct types of LEGO piece contribute to the overall complexity of objects being built [14]. These mathematical principles (known as scaling laws) can be applied to understanding both the top-down design and bottom-up emergent complexity of cities.


[1] Lende, D.   Cornelia Bargmann and the Building Blocks of Behavior. Neuroanthropology blog. February 20 (2013).

Also see an article from 2012, in which she weighs in on the idea of building a connectome: Bargmann, C.I.   Beyond the connectome: how neuromodulators shape neural circuits. Bioessays, 34(6), 458-465 (2012). 

[3] C.elegans has a complexity of just 959 cells (the brain has 302 cells). This makes this nematode a potentially tractable model for whole-organism understanding and emulation of simple behaviors (but see article [2] for difficulties in achieving this). 

See the following review article for more information: Ankeny, R.A.   The natural history of Caenorhabditis elegans research. Nature Reviews Genetics, 2(6), 474-479 (2001).

[4] Hall, S.S.   As the worm turns. Nature News. February 20 (2013).

[5] For more information on how neuropeptides may organize social and other behaviors, please see the following review in which neuropeptides are called the "dark matter" of social neuroscience: Insel, T.R.   The Challenge of Translation in Social Neuroscience: a review of oxytocin, vasopressin, and affiliative behavior. Neuron, 65(6), 768–779 (2010).

[6] Paper: Vieira, M-P., Lebedev, M., Kunicki, C., Wang, J., and Nicolelis, M.A.L.   A brain-to-brain interface for real-time sharing of sensorimotor information. Scientific Reports, 3, 1319 (2013).

In addition, here is a video of the experiment and an article in The Scientist.

[8] Rat-to-rat communication (North America to South America and back), referred to in the paper as a "rat dyad". Map courtesy Google Earth.

[9] Arbesman, S.   LEGO Meets SimCity. Wired Science, February 20 (2013).

[10] Arbesman, S.   The Scale and Context of Cities. Wired Science, March 12 (2012).

[11] Arbesman, S.   The Complexity of Cities and SimCity. Wired Science, June 14 (2012).

[12] Hutter, M.   Algorithmic Complexity. Scholarpedia, 3(1), 2573 (2008).

[13] Changizi, M.A., McDannald, M.A., and Widders, D.   Scaling of differentiation in networks: nervous systems, organisms, ant colonies, ecosystems, businesses, universities, cities, electronic circuits, and Legos. Journal of Theoretical Biology, 218(2), 215-237 (2002).

[14] Arbesman, S.   The Mathematics of Lego. Wired Science, January 6 (2012).

No comments:

Post a Comment