It's all in your head

December 6, 2006 7:56 AM

Ramón y Cajal fathered a new science with his elegant sketches of neurons. Since then, the brain has been visualized in a variety of ways: from the microscopic to the functional, from the abstract to the beautiful. The connectome, intellectual heir to the human genome project and proteomics, aims to map the entire brain network as a means of understanding cognition and behavior. Pick your favorite brain metaphor here.
posted by logicpunk (9 comments total)

Obligatory youtube link.
posted by logicpunk at 7:58 AM on December 6, 2006

Those drawings are quite nice. And I like the reasonable tone of the Connectome authors:

We emphasize that structure–function relationships are not directly evident from the connectional dataset itself. Rather, their elucidation will require further intense empirical and computational study. Depending on sensory input, global brain state, or learning, the same structural network can support a wide range of dynamic and cognitive states.

posted by OmieWise at 8:14 AM on December 6, 2006

I suspect the limitations will not be lack of functional understanding, but sheer computational complexity, where the number of possible configurations start to approach the number of molecules in the universe.
posted by StickyCarpet at 8:35 AM on December 6, 2006

Depending on sensory input, global brain state, or learning, the same structural network can support a wide range of dynamic and cognitive states.

Aren't long term memories (which result from learning) structure? I agree that in the beginning learning changes firing patterns only.
posted by vertriebskonzept at 9:24 AM on December 6, 2006

That's interesting, vertriebskonzept, particularly after reading Robert Pirsig's Zen comments. Maybe some day there will be a biological analysis of Zen. I think it has something to do with keeping new neurons firing vs. following established paths.

If you're running Firefox 2, clicking Images / Display Alt Attributes helps for that last link.
posted by weapons-grade pandemonium at 9:55 AM on December 6, 2006

Do you know who else was a pioneer in neural anatomy?
That's right. Nansen.
posted by Chrischris at 10:00 AM on December 6, 2006

Aren't long term memories (which result from learning) structure?

Kind of - it's usually regarded as the strength of synaptic connections, usually by changing the type (isoform) of receptors present, and/or how they function, at that particular synapse.

Of course, all kinds of stuff also happens close to that synapse inside the cell - phosphorylation of all kinds of different proteins, novel expression of other sets of proteins to reduce synapse disassembly, long term changes in scaffolding, possibly recruitment of soluble ribosomes for local mRNA translation, &c&c&c. Changes in the pre-synaptic side is also likely. The connectome is certainly an ambitious undertaking.
posted by porpoise at 11:10 AM on December 6, 2006

Ramón y Cajal fathered a new science with his elegant sketches of neurons.

The rumor that Cajal sketched me in the nude is completely untrue.
posted by neuron at 12:56 PM on December 6, 2006

Don't forget Camillo Golgi. His staining technique was what allowed Cajal to actually visualize neurons in the first place. The technique was great but Golgi almost missed out on sharing the Nobel with Cajal - not because of any problem with his technique, but because some of his other theories about the nervous system were out of favor and in fact quite wrong.

Damn, I love me some neurons.
posted by caution live frogs at 1:08 PM on December 6, 2006