"unlike other senses, space is not analyzed by a specialized sensory organ"
"Unlike vision, touch or smell, which are pre-wired and based on Kantian a priori knowledge, the spatial maps presents us with a new type of presentation, one based on a combination of a priori knowledge and learning. The general capability for forming spatal maps is built into mind but the particular map is not. Unlike neurons in a sensory system , place cells are not switched on by sensory stimulation. Their collective activity represents the location where the animal thinks he is"
Eric R. Kandel from " In Search Of Memory"