RatNetworks are composed of nodes and links along the lines of Catacomb's general purpose graph. There are four types of possible nodes: input, output integrate-and-fire subnetworks and vector operations. The input and output nodes are preset, and are hardwired to the rat sensory and motor systems. Vector operations and integrate-and-fire subnetworks can be configured at will.
There are two possible connection types, both flavours of RatNetLink, for propagating continuous values or spikes.
The input nodes receive position, place, visual, sound and proprioreceptive input. Output nodes connect to motor and desired-destination systems. Place input and desired-destination output are shortcuts to bypass the need for networks to generate place cells and to convert from desired destination to motor activity. The position input is not intended for use by the network but serves as a conduit for moving position information to subsequent spike analysis features which correlate position with spiking activity in particular populations. The origin of this information is in the environment withe specially marked lines indicating paths to be analysed [see the projectOnto field].
initial specifications requested and funded by Mike Hasselmo -- grant numbers NSF IBN 9996177, NIH MH 60013 and NIH MH 61492