Psychopaths seem to suffer a kind of emotional poverty that limits the range and depth of their feelings. While at times they appear cold and unemotional, they are prone to dramatic, shallow and short-lived displays of feeling. Careful observers are left with the impression that they are play-acting and that little is going on below the surface.
Laboratory experiments using biomedical recorders have shown that psychopaths lack the physiological responses normally associated with fear. The significance of this finding is that, for most people, the fear produced by threats of pain or punishment is an unpleasant emotion and a powerful motivator of behavior. Not so with psychopaths; they merrily plunge on, perhaps knowing what might happen but not really caring.
