Central influence is processed intellectually in such a manner that we can apply our critical thinking to the message. When someone tries to use reason to persuade you of something, they are using the central route. On the other hand, when someone uses emotional appeal, when they conceal their intentions in an elaborate story, or us trickery to gain your trust, or various other persuasive tactics not reliant upon reason, they are using peripheral influence . Social psychology experiments have shown very dramatically that we are capable of relying on such superficial guidelines as someone's appearance to determine whether to trust them and how to interpret their messages. We may be perfectly aware that someone gave us a free gift or that they are wearing a white lab coat, but we might not be aware that these simple things have a strong effect on our thinking processes and how we interpret what the person tells us.
Hypnotic suggestion relies greatly, in fact almost entirely, on peripheral influence.
By engaging our vivid imagination, eliciting our trust, and encouraging us to explore and become absorbed in fantasized roles, the hypnotist uses our own motivations and willingness to relax to help create the optimum conditions for cooperation. People may do unusual things during or following hypnosis, particularly stage hypnosis, but they are in control. In no sense does hypnosis demonstrate a special power possessed by the hypnotist to force people to do things that is contrary to their own motivations. Their motivations, however, may be influenced by a fantasized role they have allowed themselves to explore in conjunction with the hypnotist, in whom they have implicit trust. Neurolinguistic programming has some unique ways of describing what is going on in hypnosis, and also, like Ericksonian hypnosis, provides for the use of suggestion outside of formal hypnotic induction.