Some artists work hard to shed their technical skills and draw crude, child-like pictures. There is great artistic power in the pre-verbal, non-rational space where innocent children, raving lunatics and savage animals dwell.
One of my very favorite artists to tap this power is Jean Dubuffet, who illustrated a number of books and record album covers:
Illustration for La Lune Farcie
A selection of covers
Dubuffet was a prolific gallery painter and sculptor. A brilliant, erudite man and unconventional thinker, he was the first advocate for the art of the insane ("art brut"). I adore his work. Among my favorites are his pictures of cows:
...and his intense schizoid landscapes...
Dubuffet did thousands of drawings including a memorable series of "pisseurs"-- a droite, a gauche, and en face.
It is not easy to unlearn what you know and achieve this state. Lots of artists mimic sappy children's drawings, but very few can achieve the raw and disturbing effects that Dubuffet did.
Many of today's illustrators cluster around a few popular styles. You see them throughout the annual Spectrum anthology and the Hugo award nominees. Photorealistic artists interested in exploring a little terra incognita should consider artists such as Dubuffet. After all, Norman Rockwell kept a book of Dubuffet's art handy in his studio.