Dear Peter Thank you for your suggestion, I will also subscribe the pupil list and share the same question among this group of spetialists. According to our research, this topic is of high interest for us. Thanks Luis -- EYE-MOVEMENT mailing list ([log in to unmask]) N.B. Replies are sent to the list, not the sender To unsubscribe, etc. see http://www.jiscmail.ac.uk/files/eye-movement/introduction.html Other queries to list owner at [log in to unmask]