Cor you got to look at life through his eyes, he is understanding that those colours together mean 'home' and that there is an outside, he is learning what shapes are and colours are, understimulation is not something newborns suffer from, overstimulation is!
I used to hold jasper in the sling and walk around the house letting him look on shelves, or brush things against his face or let him feel different things.
i would take him to areas where there was alot of green because he could only see the green and then stand him in front of trees with alot of pink so he got a vibe for the different colours!
one of his favourite things to do now is to sit in a buggy at the front door and watch the traffic go past! he loves it!