Effectiveness of implicit measures of deception (e.g., sweating, eye focus, EEG) when filling out online questionnaire I'm working in my master thesis on a method of detecting user deception or lying when answering online questionnaires using his implicit feedback like sweating, eye focus, EEG etc. 

I would like if you could recommend me some related works or books or give me some tips on which implicit feedback should I focus.
If you want to estimate/classify using implicit measures, whether a user is being deceptive while filling out an online questionnaire ... then methods such as EEG are not suitable.

Recording EEG data takes a lot of preparation and at least one experimenter to prepare the "user" (in your case the person filling out the questionnaire). And if you are talking about online questionnaires, I do not see a point in having an experimenter visit the user.

On the other hand, using (often toy-like) dry-electrodes that could be prepared by a single person, will not yield a sufficient data quality.

I think the easiest might be to consensually access the webcam of a user and evaluate the video stream for e.g., eye blinks, or other tentative variables.

Generally, this sounds like a very difficult task that will probably result in a high number of false positives and false negatives.