Because symptoms are so severe, many people who experience a panic attack may believe they are having a heart attack or other life-threatening illness and may go to a hospital ER. Panic attacks may be expected, such as a response to a feared object, or unexpected, apparently occurring for no reason. The mean age for onset of panic disorder is 22-23. Panic attacks may occur with other mental disorders such as depression or PTSD.
The philosopher Søren Kierkegaard, in The Concept of Anxiety (1844), described anxiety or dread associated with the "dizziness of freedom" and suggested the possibility for positive resolution of anxiety through the self-conscious exercise of responsibility and choosing. In Art and Artist (1932), the psychologist Otto Rank wrote that the psychological trauma of birth was the pre-eminent human symbol of existential anxiety and encompasses the creative person's simultaneous fear of – and desire for – separation, individuation, and differentiation.
Selective mutism: A somewhat rare disorder associated with anxiety is selective mutism. Selective mutism occurs when people fail to speak in specific social situations despite having normal language skills. Selective mutism usually occurs before the age of 5 and is often associated with extreme shyness, fear of social embarrassment, compulsive traits, withdrawal, clinging behavior, and temper tantrums. People diagnosed with selective mutism are often also diagnosed with other anxiety disorders.
A person with separation anxiety disorder is excessively fearful or anxious about separation from those with whom he or she is attached. The feeling is beyond what is appropriate for the person’s age, persists (at least four weeks in children and six months in adults) and causes problems functioning. A person with separation anxiety disorder may be persistently worried about losing the person closest to him or her, may be reluctant or refuse to go out or sleep away from home or without that person, or may experience nightmares about separation. Physical symptoms of distress often develop in childhood, but symptoms can carry though adulthood.
Separation anxiety disorder: Separation anxiety is often thought of as something that only children deal with; however, adults can also be diagnosed with separation anxiety disorder. People who have separation anxiety disorder have fears about being parted from people to whom they are attached. They often worry that some sort of harm or something untoward will happen to their attachment figures while they are separated. This fear leads them to avoid being separated from their attachment figures and to avoid being alone. People with separation anxiety may have nightmares about being separated from attachment figures or experience physical symptoms when separation occurs or is anticipated.