Using a reverse-engineering method similar to that of the Blue Brain Project, Jenn-Kang Hwang and her team at the National Tsing Hua University in Taiwan have engineered a computer-simulated fruit fly brain with single-cell precision.
The researchers stained (using green-fluorescent protein) and imaged tens of thousands of neurons in the fly brain and used complex gene-marking procedures to find out which cells interacted with one another.
These methods helped them elucidate the architecture of specific networks of cells, and that information allowed for a reconstruction of the pathways of functional brain regions, and ultimately the full structure of the brain. The authors compare their model of interacting neurons to a city highway system, writing:
Each unit is like a city containing local intersected streets and avenues linked to other cities through multi-lane highways without cross-traffic. Sometimes, several geographically closed units form a family working together for a specific function requiring intensive information processing.
The researchers also address the age-old brain/computer comparison, pithily stating:
It seems that a fly brain is smarter and more complicated than any computer built thus far.
However, their work by no means represents a full understanding of the workings of the fruit fly brain and the translation of neural network to behavior (that level of understanding is a ways away); rather, it’s a useful visual tool for testing hypotheses about specific neural interactions in the fruit fly brain, and locating neurons of interest. It’s akin to navigating on a road trip – why use a glove compartment full of small, unconnected state maps when you can use a nice, big road atlas?
The Hwang team has published the results of their brain-mapping project online for free and open access, just like the Human Genome Project did in 2003. To see the exciting images and videos, go here.