Synchronizing with Trigger Signal from MRI Scanner

[Hilke Plassmann]

Hi,

I have a question concerning the use of e-prime for fMRI experiments.  
I would like to synchronize the ImageDisplay Onset with the trigger  
signal from the scanner. This signal is send via a response box I'm  
using and is coded as a '5'. That means that every 2secs (TR=2secs)  
the scanner sends a '5' to the PC in the control room which can  
theoretically be detected by E-Prime. Does anybody know how to tell  
Eprime to use the Trigger Signal to start the Image Display Onset? Or  
to use the signal to adjust the timing of the Eprime task? Many  
thanks for your help.

Hilke