Methods for deriving an indication of truth or deception are disclosed. Some methods include (a) monitoring the activation of a plurality of regions of a subject's brain, while the subject responds to questions and (b) measuring one or more physiological parameters while the subject responds to questions and combining the results of (a) and (b) to form a composite evaluation indicative of truth or deception in the subject's response. Another method further includes (c) measuring one or more behavioral components while the subject responds to questions and then combining the results of (a), (b), and (c) to form a composite evaluation indicative of truth or deception in the subject's response. Methods for scoring, weighting, and combining the measurements for (a), (b), and (c), and combinations thereof, are also disclosed.