Anxiety is the subjective feeling of apprehension, dread, or foreboding ranging from excessive concern about the present or future to feelings of panic, accompanied by a variety of autonomic signs and symptoms, with or without a stressful situation. The focus of anticipated danger may be internal or external. The state of anxiety seems to place the defensive physiological mechanisms in a heightened state of preparedness, thereby facilitating and stimulating the fight-flight response only in case the threatening event occurs. Anxiety is often distinguished from fear in that fear is a more appropriate word to use when threat or danger exists in the real world. Anxiety is more reflective of a threat that is not apparent or imminent in the real world, at least not to an experienced degree.