To imagine a rose visually as a mime does, there is a great deal of kinesthetic sense memory employed. I remember the velvey feel of the red rose, the prickliness of its thorns and rough, sticky, bumpy stem. I even smell the dirt and grass that hold it in the ground, the horizontal plane from which it grows.
When these senses create it for me, others see what I see. It is there in my mind and in the reality which I re-create.
What is the effect upon my nervous system? Do I activate the neurons the same as if I am really touching a rose? If I am soothed is my mind and body responding likewise? It seems the answer is "yes". Our mind is a sixth sense. We have great untapped powers and can learn how to harness it.
So...the question then appears...does the flower exist?