Learning how the brain does its coding

By John Timmer

A single giant neuron makes many connections.

Science/AAAS

Most organisms with brains can store and process a staggering range of information. The fundamental unit of the brain, a single neuron, however, can only communicate in the simplest of manners, by sending a simple electrical pulse. The challenge of understanding how information is contained in the pattern of these pulses has been bothering neurobiologists for decades, and has been given its own name: neural coding.

In principle, there are two ways coding could be handled. In dense coding, a single neuron would convey lots of information through a complex series of voltage spikes. To a degree, however, this creates as many problems as it solves, since the neuron on the receiving end will have to be able to interpret this complex series properly, and separate it from operating noise.

The alternative, sparse coding, tends to be used for memory recall and sensory representations. Here, a single neuron only conveys a limited amount of information (i.e., there’s something moving horizontally in the field of vision) through a simple pulse of activity. Detailed information is then constructed by aggregating the inputs of lots of these neurons.

Read More>>

Advertisements

Comments are closed.

%d bloggers like this: