The term demand characteristics originated in Martin Orne's work as the test group understood what was the investigation and acted consequently. Thus, the way an experiment is built may lead participants to answer unconsciously to what they believe the researcher wants. When the participants form a notion of where the experiment is heading, they probably behave accordingly. One way to avoid the effects of demand characteristics on research is to use deception and guide participant to act more naturally as they cannot guess the purpose of the experiment.
