perception vs perceptual

perception is a noun but perceptual is not a noun.

Word	Noun	Adjective	Verb	Adverb
perception	Yes	No	No	No
perceptual	No	Yes	No	No

perception (noun)	perceptual (noun)
becoming aware of something via the senses
the process of perceiving
the representation of what is perceived; basic component in the formation of a concept
a way of conceiving something
knowledge gained by perceiving

perception (adjective)	perceptual (adjective)
	of or relating to the act of perceiving