Anxiety is distinguished from fear, which is an appropriate cognitive and emotional response to a perceived threat and is related to the specific behaviors of fight-or-flight responses, defensive behavior or escape. Anxiety occurs in situations only perceived as uncontrollable or unavoidable, but not realistically so. David Barlow defines anxiety as “a future-oriented mood state in which one is ready or prepared to attempt to cope with upcoming negative events,” and that it is a distinction between future and present dangers which divides anxiety and fear.