I came across this thesis online (and there's a book at Amazon, too).
A Portrait of the Artist as a Very Young or Very Old Innovator: Creativity at the Extremes of the Life Cycle
David W. Galenson
in which he attempts to indicate a distinction between what he calls conceptual and experimental innovators.
Orson Welles made Citizen Kane, his greatest movie, when he was 25 years old; Frank Lloyd Wright designed Fallingwater, his most famous house, when he was 70. Contrasts as great as this raise the question of whether there is a general explanation of when in their lives great innovators are most creative. For each of seven artistic disciplines, this paper examines a major innovation made by a very young artist, and another made by an old one, with the goal of understanding the role of the artist's age and experience in the accomplishment. The analysis shows why youth was necessary for the innovations of such conceptual artists as F. Scott Fitzgerald, Arthur Rimbaud, Maya Lin, and Orson Welles, all of whom produced their masterpieces before the age of 30, and why extensive experience was necessary for the innovations of such experimental artists as Piet Mondrian, Elizabeth Bishop, Henrik Ibsen, and Frank Lloyd Wright, all of whom made major contributions after the age of 60.
This paper demonstrates the generality of the distinction between conceptual and experimental innovators in artistic disciplines, and the value of the analysis in explaining the very different relationships between age and creativity for the two types of artist.