Remember?

Fleeting picture
Image in my brain
Burned in to my thoughts
It leaves me sleepless
Wondring what it was
I can't recall it
Or attempt to describe
So I claw and search
For elusive words
They still don't come
But it persists and returns
And I still grapple to relive
That which bewilders me
So familiar
And yet unidentified
Tip of my tongue
It's always there
That flash of recognition
But flees before it's caught
To some dark corner where it hides
It's only a flash
A moment in my mind