Can science put a value on art?
Brain injuries and post-traumatic stress disorder affect tens of thousands of US veterans of the wars in Iraq and Afghanistan.
It is known that art therapies can help with the psychological effects of these invisible wounds, but can they promote physical healing?
A top military hospital near Washington is conducting the first comprehensive clinical tests to find out how art works.
The National Intrepid Center of Excellence is carrying out the study as part of a broader effort to measure the value of creative endeavours in all stages of human development.
The BBC's Jane O'Brien went to the new military medical facility at Walter Reed National Military Medical Center in Bethesda, Maryland, to find out more.