It forms the paleocortex and is rudimentary in the human brain.

[citation needed] The term rhinencephalon has been used to describe different structures at different points in time.

[2] Some references classify other areas of the brain related to perception of smell as rhinencephalon, but areas of the human brain that receive fibers strictly from the olfactory bulb are limited to those of the paleopallium.

[clarification needed (see talk)] The development of the rhinencephalon varies among species.

A small area where the frontal lobe meets the temporal lobe and the area of cortex on the uncus of the parahippocampal gyrus (both belonging to the olfactory cortex) have a different structure (so called "allocortex") than most of the telencephalon and are phylogenetically older (so called paleocortex).