Trained agents may be able to control their breathing rate, pulse, skin resistance, blood pressure and temperature, but for everyone else, manipulation of such a test is almost impossible. If your partner has cheated on you, an experienced examiner with his high-quality equipment will almost certainly uncover lies, infidelities and fraud. Even a target person's attempt to control their behavior is recognized by the expert. However, nervousness does not affect the result and is a normal occurrence in such a test.