However , other studies have challenged that the underlying cause is not age , but are due to artistic movements which occur in certain periods .
Galenson 's distinction between conceptual and experimental is based upon evidence from the age in which artists were most productive creatively .
Other studies have challenged that the underlying cause is not age , but are due to artistic movements which occur in certain periods .
Galenson 's distinction between conceptual and experimental is based upon evidence from the age in which artists were most productive creatively .