What is described above concerned the input map or "inmap" (corresponding to the spatial distribution of the afferent axons from one source to one target). This does not correspond necessarily to the output map or outmap (corresponding to the distribution of the neurons in relation to their axonal targets). Physiological studies and transsynaptic viral markers have shown that islands of pallidal neurons (only their cell bodies or somata, or trigger points) sending their axons through their particular thalamic territories (or nuclei) to one determined cortical target are organized into radial bands. These were assested to be totally representative of the pallidal organisation. This is certainly not the case. Pallidum is precisely one cerebral place where there is a dramatic change between one afferent geometry and a completely different efferent one. The inmap and the outmap are totally different. This is an indication of the fundamental role of the pallidonigral set: the spatial reorganisation of information for a particular "function", which is predictably a particular reorganisation within the thalamus preparing a distribution to the cortex.