Well I do not know the perfect answer but since it is an unanswered question I will try to answer. Biometric Recognition is something that senses the muscles. This is similar to the touch screens. What I think is you should try to read the mathematics behind the touch screens or Biometric Recognition and try to implement with the help of that mathematical equation in Matlab.
Thanks you for the reply. I will download your attached file and have a look at it. but I was looking for the logic of Recognition in simple words! is it based on simlpe crosscorrelation of vector?