Help Make Neurological Discoveries with the Eyewire Project

In neuroscientist Sebastian Seung's book, Connectome: How the Brain's Wiring Makes Us Who We Are is to be released, and it promises to delve into some of the key issues around whole brain scanning.  To study a network of neurons it would be helpful to have a map of the network’s connections. Such mapping has been difficult or impossible in the past, but is becoming more feasible due to technological advances. One technology is known as serial electron microscopy, which involves cutting extremely thin slices of brain tissue using a diamond blade, acquiring a sequence of two dimensional images, and assembling them into a three dimensional image of every neuron and synapse in the tissue.  The technology for this process exists, however decoding the slices is the difficult part. 

Last year we named the Mouse Connectome Observatory as the top innovation of the year.  At the Max Planck Institute for Medical Research in Heidelberg, Germany, neuroscientists in the laboratory of Winfried Denk  have also taken extremely thin slices of brain tissue and generated electron-microscope images of all the neural connections within each slice.

Likewise, high-resolution images are being acquired in the laboratory of Jeff Lichtman at Harvard University. However, the next step — mapping those connections — is extremely time-consuming. Seung estimates that it would take 100,000 years for a lone worker to trace the connections in one cubic millimeter of brain tissue.

To address this issue, Seung and his colleagues have developed an AI system, which they presented at the International Conference on Computer Vision and the Neural Information Processing Systems Conference in 2009. Despite its efficiencies, the system still requires human guidance, so the researchers are enlisting crowdsourcing the help of the general public through a website called eyewire.org. They are starting with the retinal neuron connectome.  “The brain is like a vast jungle of neurons,” Seung says. “They’re like trees that are all tangled up together, and people can help us explore that.”

According to the website,

Inside the retina, tucked away at the back of the eye, lies an incredibly dense tangle of interconnected neurons. If we can map the many connections between these cells, we will be closer than ever to understanding how vision works. To achieve this, we need something more intelligent than even the most powerful supercomputer — you. 

You can help discover things that machines can't. Delve into the microscopic realm of the retina to glimpse the twists and turns of neurons hitherto unseen. You will be at the forefront of scientific exploration as you chart the entangled branches of those tree-like cells called neurons. Join us to explore the eye's jungle.

Participants in the Eyewire project will help guide the computer program when it loses track of where a neuronal extension goes amidst the tangle of neurons.  The inner workings of individual neurons are fascinating by themselves, but the story gets much more complex when we look at the connections between neurons. When the axon of one neuron comes into contact with a dendrite of another, the two can communicate through a special junction called a synapse. The axon sends information to other neurons by releasing molecules known as neurotransmitters. Dendrites receive signals from other neurons by sensing neurotransmitter molecules. (Direct transmission of electrical signals between neurons can also occur.) A typical neuron is connected to thousands of other neurons! Together these cells form a highly interconnected network.

Eyewire is set up like a game.  While the computer algorithms are good at linking neural connections between slices, they are not 100% perfect.  That is where the crowdsourcing comes in.   It is from this interface that participants will explore and color neurons. By tracing neurons mapping their connections can be completed thereby creating connectomes. Think of it as a 3-D coloring book. Each task explores a small cube of data.

“The person can click the mouse and say color here, and the computer starts coloring again, and keeps going, and then stops again when it’s uncertain. So you’re guiding the computer,” Seung says. Furthermore, the AI system becomes “smarter” as people guide it, so it will need less and less help as it goes on.

As each coloured slice is added to the stack, a 3D view of the connectome is formed, like the ones pictured below:

Rather than tackling the human brain right away, the researchers are beginning with a 300x350x 80-micron slice of mouse retinal tissue. Images of just this small piece of tissue take up a terabyte of data, or enough to hold 220 million pages of text.

While a daunting task, progress in connectomics (mapping the 100 billion neurons in the human brain) is comparable to mapping the human genome.  At first the progress is incredibly slow, and it seems impossible, but as incremental progress builds on itself, the progress becomes exponential.


http://eyewire.org