How to calculate Reaction Time of video response stimuli

How would I, successfully extracted participants' overt word reading reaction time data from their responses within the MRI scanner which is in audio file. Can you please suggest me code coz i am new to matlab.

Answer 1

[Sachin Ganjare]

Refer below links:

http://en.wikibooks.org/wiki/MATLAB_Programming/Psychtoolbox/Example_Code/xsearch

http://www.psychtoolbox.org/HomePage

Hope it helps!!!