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Anxiety can be defined as ‘a state consisting of psychological and physical symptoms brought about by a sense of apprehension at a perceived threat’. Fear is similar to anxiety except that with fear the threat is, or is perceived to be, more concrete, present, or imminent.
Symptoms
The psychological and physical symptoms of anxiety vary according to the nature and size of the perceived threat, and from one person to another. Psychological symptoms include feelings of fear and dread, an exaggerated startle reflex, poor concentration, irritability, and insomnia.
In mild to moderate anxiety, physical symptoms such as tremor, sweating, muscle tension, a faster heart rate, and faster breathing arise from the body’s so-called fight-or-flight response, a state of high arousal fuelled by a surge in adrenaline.
In severe anxiety, hyperventilation, or over-breathing, can lead to a fall in the concentration of carbon dioxide in the blood. This gives rise to an additional set of physical symptoms, among which chest discomfort, numbness or tingling in the hands and feet, dizziness, and faintness.
Purpose
Fear and anxiety can be a normal response to life experiences, protective mechanisms that have evolved to prevent us from entering into potentially dangerous situations, and to help us escape should they befall us regardless. For example, anxiety can prevent us from coming into close contact with pestilent or venomous animals such as rats, snakes, and spiders; from engaging with a much stronger or angrier enemy; and even from declaring our undying love to someone who is unlikely to spare our feelings.
If we do find ourselves caught in a threatening situation, the fight-or-flight response triggered by fear can help us to mount a suitable response by priming our body for action and increasing our performance and stamina.
In short, the purpose of fear and anxiety is to protect us from harm and, above all, to preserve us from death—whether literal or figurative, biological or psychosocial.
Problem
Although some degree of anxiety can improve our performance on a range of tasks, severe or inappropriate anxiety can have the opposite effect and impair our performance. Thus, whereas a seasoned actor may perform optimally before a live audience, a novice may suffer from stage fright and freeze.
From a medical standpoint, anxiety becomes pathological when it becomes so severe, frequent, or longstanding as to prevent us from doing the sorts of things that most people take for granted, such as leaving the house or even just our bedroom. I once treated a patient with a severe anxiety disorder who, to avoid crossing the corridor from bedroom to bathroom, urinated into a bottle and defaecated into a plastic bag.
Pathological anxiety often owes to a primary anxiety disorder, although in some instances the anxiety is secondary to another psychiatric disorder such as depression or schizophrenia, or to a medical disorder such as hyperthyroidism or alcohol withdrawal.
Prevalence
Primary anxiety disorders are increasingly common, now affecting as many as one in five Americans in any given year. They commonly present in one or more patterns such as a phobic anxiety disorder, panic disorder, generalized anxiety disorder, a conversion disorder, post-traumatic stress disorder (PTSD), or a culture-bound syndrome.
Causes
Mental disorders associated with anxiety include mood disorders such as depression, psychotic disorders such as schizophrenia, and eating disorders such as anorexia or bulimia. Physical disorders associated with anxiety include endocrine disorders such as hyperthyroidism, Cushing’s disease, and hypoglycaemia, as well as drug and alcohol intoxication or withdrawal.
Genetic, environmental, and psychological factors can all predispose or contribute to an anxiety disorder. A genetic predisposition to anxiety disorders may manifest as 'neurotic' personality traits. The core feature of neurosis is anxiety, but neurosis can also manifest as a range of other problems such as irritability, perfectionism, and obsessive-compulsive tendencies.
In terms of environmental factors, an anxiety disorder may be triggered or perpetuated by stress and stressful events, especially those involving a threat. They may also result from childhood traumatic events such as parental neglect or physical abuse.
In many cases, psychological factors, often superimposed upon genetic and environmental factors, play an important role. According to cognitive behavioural theories, anxiety disorders result from inappropriate thought processes and belief systems. According to psychoanalytic theories, anxiety disorders are rooted in childhood events such as separation or loss, and in unresolved childhood conflicts of psychosexual development.
Management
Ultimately, it is difficult to separate the psychological from the physical, since the psychological, which arises in the brain, is also in some sense physical, and has manifold physical manifestations. However, anxiety disorders that are secondary to another mental or medical disorder are usually best treated by treating the primary, or underlying, cause.
For further advice on anxiety management, see my related article, Coping with Anxiety.
Read more in The Meaning of Madness.
