An Eye for the Eye: Mapping Retinal Neurons with the CrowdMay 23rd, 2012 by Ville Miettinen
If you’ve ever had a close encounter of the lamppost kind you’ll know that the eye can sometimes deceive us. But considering just how complex the eye is you might think it would let us down more often.
You may remember from your high school biology classes that basically (very basically) light enters the eye through the pupil and falls on photo receptive cells called rods and cones. These send an electrical impulse that travels through the optic nerve and into the brain, creating the sensation we experience as sight. All of this happens in a fraction of a second.
Inside the retina are 5 different types of neuron (although some scientists believe there may be as many as 60) and there are millions of each type in each eye. With some 100 billion neurons in the brain as a whole, trying to understand how it all works is no easy task.
Here’s looking at you Crowd
Undeterred by these gargantuan numbers, a group from MIT (who must have a few neurons to spare) has developed the EyeWire project. The project incorporates some ingenious techniques to map the mind-bogglingly complex web of neurons in the retina.
Beginning with a series of cross sections through the retinal neurons of a flatworm, they developed a sophisticated image processing algorithm that created a 3D model of the neural network from the 2D images.
To check the accuracy of the 3D models they required something even more sophisticated than the algorithm. Realizing that the very subject of their inquiry was probably the best tool for the job the team broke the images up into small blocks and distributed them online for volunteers to verify by sight.
The result is a sort of optical puzzle. The player traces a colored neuron through a series of 2D images as it weaves and branches its way through clusters of seemingly identical blobs. Your task is to fill in any color missing from the neuron.
At first it seems an impossible task but it quickly becomes almost intuitive. After several minutes of squinting at a series of blobs it is incredibly satisfying to find a new branch and have it pop up on the 3D window in the corner of your screen.
The most determined players will get a position on the leader board. Maintaining that position or moving up the board should provide ample motivation to keep people coming back to what is an enjoyably challenging and surprisingly relaxing way to spend your time.
The Future Looks Bright
As well as providing enjoyment for its volunteers Eyewire is also contributing to our understanding of the eye’s nervous system. Potentially the research could result in treatments for disorders like epilepsy and new ways to revert and prevent different types of blindness.
The method is already being applied to the rest of the brain’s neurons with the “Wired Differently” program which could result in better understanding and treatments for conditions like autism and schizophrenia. Perhaps one day we may even understand the brain well enough to prevent the hilarious but debilitating problem of walking into glass doors.