Do You Want a Map of Your Brain?



If you've ever wondered (as one does), "Why don't I have a map of all the neurons in my brain?" 

...Well, now you can.

If, that is, like me, you have a brain the size of a fruit fly.

That's right. All of the nerve cells and connections between them in a larval fruit fly brain have been fully mapped out by scientists.

Granted, a fruit fly brain (like my brain) is not that large, but this it IS larger than the "brains" of sea squirts and worms.

Before this, scientists had only been able to fully diagram the brain circuitry of three organisms - a sea squirt and two types of worm. Those buggers have only have a few hundred neurons, while fruit flies have--as we now know--three thousand.

They used a fancy microscope to capture pictures of the brain, and then pieced them all together like a puzzle. They even traced each individual nerve cell to create a 3D model of the brain.

"Fruit flies (Drosophila melanogaster) share a wide range of behaviors with humans, including integrating sensory information and learning. Larvae perform nearly all the same actions as adult flies — except for some, like flying and mating — but have smaller brains, making data collection much faster (SN: 7/19/18).
The idea for this project came 12 years ago, says neuroscientist Marta Zlatic of the MRC Laboratory of Molecular Biology in Cambridge, England. At that time, she and her colleagues captured electron microscope images of the entire larval fruit fly brain. They then stitched those images together in a computer and manually traced each neuron to create a 3-D rendering of the cells. Finally, the team found the connections where information gets passed between the cells, and even determined the sending and receiving ends."

After all that work, the researchers discovered over 3,000 nerve cells in a fruit fly's brain, and more than half a million tiny connections between them. These connections are called synapses, and they're how nerve cells communicate with each other. By mapping out all of these synapses, the researchers can start to understand how a fruit fly's brain works.

By exploring the connections between cells, the researchers were able to identify 93 different types of neurons, each with its own unique shape and function. They also discovered that 75% of the most well-connected neurons were linked to the brain's learning center.

We probably don't want researchers to map our own brains using the same methods they did with fruit flies. (And if there is a group of mad scientist somewhere mapping human brains like this, it's probably on a black op site.)

However, as both methodology and comparative knowledge gets better, perhaps a non-invasive, personalize brain mapper is on the horizon.