On the connectome

Via Twitter, MnkyMnd thinks this should be required reading for every scientist:

In that Empire, the Art of Cartography attained such Perfection that the map of a single Province occupied the entirety of a City, and the map of the Empire, the entirety of a Province. In time, those Unconscionable Maps no longer satisfied, and the Cartographers Guilds struck a Map of the Empire whose size was that of the Empire, and which coincided point for point with it. The following Generations, who were not so fond of the Study of Cartography as their Forebears had been, saw that that vast map was Useless, and not without some Pitilessness was it, that they delivered it up to the Inclemencies of Sun and Winters. In the Deserts of the West, still today, there are Tattered Ruins of that Map, inhabited by Animals and Beggars; in all the Land there is no other Relic of the Disciplines of Geography.

On Exactitude in Science (Borges, 1946)

Watching a brain in motion

And science steadily advances. It was only last July that I posted a video showing the activity of all the neurons in a brain. But that animal was stuck in place – not moving freely (though it was in virtual reality).

Jeffrey Nguyen and Andrew Leifer just uploaded their manuscript detailing their work imaging the whole brain of an animal that is freely moving. The animal is just locomoting around like nobody is their boss. That’s important as a lot of evidence points to neural activity being different when an animal is restrained and when it is allowed to move of its own volition. This technical feat is particularly exciting because the animal is C. elegans, which means that we know how all of the neurons are connected (we have the connectome). Here’s a video:

What you are seeing is a wormlike animal bend its nose from right to left (see the green lines moving out from the center mass? Those are processes sent to the sensory receptors at the very tip of the nose of the animal). I assume the animal is moving during this, but the whole image is stabilized.

There is a smoother/faster version hereHere is another videoHere’s a description of the work from Technology Review.