Tag Archives: science

Mapping the brain’s semantic space

A color-coded map of four dimensions of the semantic space. The branches show "is-a" relationships.
A color-coded map of four dimensions of the semantic space. The branches show “is-a” relationships.

This is one of those moments in science that makes me think I’m so lucky to be alive right now. A team of scientists at UC Berkeley have found a way to map the brain’s representations of objects into a shared semantic space— a multidimensional space in which related things are nearer than unrelated ones. And there’s reason to believe this might be not just a semantic space, but the semantic space: they ran their test on five different people, and found that the first four dimensions of this semantic space were the same for all five subjects–dimensions easily labeled with ideas like moving/stationary, man-made/natural, animate/inanimate, and so on. In other words, the brain’s way of relating different objects might be something we all share at much more than a superficial level. This alone is pretty mind-blowing to me.

As if that weren’t enough, they’ve also created a very cool interactive visualization that shows how all of this plays out on the surface of an actual brain. (That page requires WebGL and a lot of memory, so if you’re reading this on an older device, you might want to just watch the video instead. Actually, you should watch the video anyway, because it’s really well done!)

Go science!

The Coffee Ring Effect

Why do coffee stains always have a dark ring around the edge? It’s because the water’s surface is curved: it evaporates more quickly near the edges, causing it to flow outward from the middle, carrying coffee particles with it. We cited some early research demonstrating this effect in our 1997 watercolor paper, but now there’s video that actually shows the process happening at a microscopic scale. (Thanks Eric for the link!)

Can you teach yourself synaesthesia?

Neuroscientist Olympia Colizoli has done an interesting experiment where she tried inducing synaesthesia in non-synaesthetes:

To test the idea, they gave seven volunteers a novel to read in which certain letters were always written in red, green, blue or orange (see picture). Before and after reading the book, the volunteers took a “synaesthetic crowding” test, in which they identified the middle letter of a grid of black letters which were quickly flashed onto a screen. Synaesthetes perform better on the test when a letter they experience in colour is the target letter.

The volunteers performed significantly better on this test after training compared with people who read the novel in black and white.

I’m curious as to how significant the effect turned out to be for non-synaesthetes. (I also wonder: what was the novel? Something by Nabokov maybe? ;-) Unfortunately I can’t find Colizoli’s data on line anywhere, as her research appears to have been presented as a conference poster session rather than a full publication. But hopefully we’ll be hearing more about this in the near future…

Update: You can read a more detailed abstract of Colizoli’s experiment over at synesthesia.info.