Play sound and continu in the dial plan

hello all !

I am trying to do a lot of things in my dialplan!
In fact I do vocal recognition.
and I have to do :
1: playback()
2: voice recognition !

and I want that to play sound and during the song execute the exten of voice recognition…

In fact, I want to do an other exten during a son played!

anybody have an idea???

exten => s,n,Background()