Apparent Fear
This is not the authentic face of fear. This is a woman who is simulating the face of fear for a photographer. In order to show a photograph of a person who is genuinely fearful, a very improbable series of coincidences would have to occur. A photographer would have to be present with the camera ready at the exact time that a person became fearful. This is very unlikely. So we have here a pose showing what most people would recognize as fear.
In the early 1790s, electricity was a novelty. Luigi Galvani demonstrated the electrical nature of nerve action by placing live wires on frogs' legs, thereby making them move. A few decades later, Dr. Duchenne photographed his own experiments on a human. He placed electrodes on a man's face and recorded the expressions that resulted from the action of the muscles. The man in the above photograph is not experiencing fear, but his facial muscles have been made to move in such a way as to mimic the expression of that emotion. Dr. Duchenne's photographs helped isolate the outward appearance of an emotion from its genuine occurrence in the nervous system.
Apparent fear is used in the theater and in cinema. Being a basic human emotion, fear is often portrayed in these dramatic media. Actors and actresses can easily mimic fear through the use of voluntary facial muscles. In many cases, it is almost indistinguishable from real fear. However, the observer always knows that he or she is watching a theatrical presentation. For this reason, apparent fear does not generate as intense a reaction in the observer as does real fear.