Visualizing Ethernet Speed

anthemaniac writes "In the blink of an eye, you can transfer files from one computer to another using Ethernet. And in the same amount of time, your eye sends signals to the brain. A study finds that images transferred to the brain and files across an Ethernet network take about the same amount of time." From the article: "The researchers calculate that the 100,000 ganglion cells in a guinea pig retina transmit roughly 875,000 bits of information per second. The human retina contains about 10 times more ganglion cells than that of guinea pigs, so it would transmit data at roughly 10 million bits per second, the researchers estimate. This is comparable to an Ethernet connection, which transmits information between computers at speeds of 10 million to 100 million bits per second."

Comments

Neuroscience != Computer Science

[KerberosKing]

I am not sure that thinking of signals from the eye to the brain work the same way as computer networks is very helpful. I don't think that there is the same sort of contention in a nervous system as there is in ethernet. Synapses as we understand them today do not appear to have any sort of collision detection. Neurons may have tens of thousands of other neurons that they are connected to in a many-to-one configuration and the whole process is analog, which is very different than ethernet frames. Also a single ganglion cell may send "10 million bits" of information, but the optic nerve is made of many such cells in parallel. I would not be surprised if our current estimates are wrong by at least an order of magnitude.

Neurons make my head hurt

[BilZ0r]

The OP doesn't say that a single retinal cell transmits 10 million bits a second, but that the whole eye does. On top of that, while discussion of collition detection is pointless, thinking about the information a neuronal population can encode does have some merits. Although it's relatively pointless (at least now) to compare the eye to an ethernet, it has uses in comparing different neural populations.

The problem is that getting bitrates for neuronal populations is more of an art that a science. The sum total of information passed on by a neuron can not be computed simpley by it's spiking rate. Large numbers of parameters alter the actual chemical I/O relationship of a neuron. Resting membrane potential before spiking, whether it shows short term facilitation/depression etc...