'Giant' Neuron Regulates 50,000 Other Neurons

Scottingham sends this quote from PhysOrg: "A single interneuron controls activity adaptively in 50,000 neurons, enabling consistently sparse codes for odors (abstract). The brain is a coding machine: it translates physical inputs from the world into visual, olfactory, auditory, tactile perceptions via the mysterious language of its nerve cells and the networks which they form. Neural codes could in principle take many forms, but in regions forming bottlenecks for information flow (e.g., the optic nerve) or in areas important for memory, sparse codes are highly desirable. ... This single giant interneuron tracks in real time the activity of several tens of thousands of neurons in an olfactory centre and feeds inhibition back onto all of them, so as to maintain their collective output within an appropriately sparse regime. In this way, representation sparseness remains steady as input intensity or complexity varies."

Comments

Nice summary ...not!

[spikenerd]

Since the summary is somewhat ...lacking, here's my attempt to translate it. (Disclaimer: I am not a neuroscientist, and I really only skimmed it anyway.)

"We studied the olfactory system of locusts, and found that all of the smell information seems to pass through a single neuron with a lot of incoming connections. This single neuron does not send outgoing signals in spikes as most other neurons do, but instead releases a chemical that suppresses other neurons. It uses this method to sort-of "average" all of the incoming signals together. Also, this system involves a feedback loop. We think that this whole arrangement is set up to generate sparse-codes, which is our favorite way to reduce information down to a small number of dimensional values. We hope that mammals use similar systems, and that this might eventually help lead to an understanding of how brains reduce large amounts of information into small concepts."