Cause of Phobias & Causes of Panic Attacks

Phobias and panic, like all anxiety disorders, disturb many areas of a person's functioning. Take the woman who has agoraphobia. Her BEHAVIOR changes when she has to quit her job because she believes she is unable to ride the bus. Her THINKING goes awry when she judges the risk she faces. The memory of past FEELINGS of panic on the bus, when she was sure she would die, produces alterations in her PHYSIOLOGY as her heart pounds, her head gets dizzy, and her hands sweat. Her behavior, thinking, emotions, and her body's physiological responses are all involved in her agoraphobia.

Evidence of these effects has guided research investigators who have tried to understand the causes of anxiety disorders. They have formed their theories by observing patients, listening carefully to what they say, and measuring their functioning in the laboratory. Scientists then go beyond these observations to test theories, either in the clinic or in scientific experiments. These experiments show that other aspects of anxiety and related disorders are not as clearly evident. Some of the most influential or promising theories and bodies of research are described below.


PSYCHODYNAMIC THEORIES
One possible cause of anxiety that is difficult for a nonspecialist to observe is psychological conflict arising from emotions and impulses that remain unconscious (outside of the person's awareness). Much of the theory proposed by Sigmund Freud early in this century assumes that such unconscious forces, mostly deriving from childhood, profoundly influence adult life, including abnormal anxious states. These influences, for the most part, are inferred from the memories and associations of patients who undergo intensive, prolonged therapy. Until the last two or three decades, Freud and the psychoanalytic investigators who revised his theories were the dominant force in explaining and treating anxiety-related conditions. Although now out of fashion in academic settings, the ideas of the psychoanalytic school have influenced thinking throughout society, especially in clinics where people are treated for mental health problems.

In the view of psychoanalysts, anxiety is a signal of danger - a danger that is not real and present, but rather, is carried over from the memories and imaginations of childhood. Often, these dangers involve fantasies of loss or love (or actual separation from loved ones) or other fantasies that express guilt or sexually related events. When these fantasies are activated in adulthood - perhaps because something happens that the patient associates with the fantasies - they give rise to anxiety. The anxiety may be conscious or unconscious. In either case, it makes the person act defensively - that is, attempting to get away from the threat or, more often, to stop the fantasy from ever occurring by regulating or inhibiting the wishes that give rise to fantasies of danger. Because this defensive behavior relieves the anxiety, it tends to be repeated: It is, in other words, learned.

Modern psychodynamic research (that which focuses on mental conflicts) has put a great deal of emphasis on the anxiety that accompanies real or feared separation from a caretaker during childhood. Individuals who, as children, became extremely anxious whenever they were separated from their parents seem to be especially likely to develop agoraphobia later in life. Some 42 percent of agoraphobic patients report a history of childhood separation anxiety. This statistic suggests that agoraphobia may build on a foundation already present in early life or represent the aftermath of unresolved childhood separation anxiety.

In contemporary psychodramic models, the person with agoraphobia avoids situations that symbolize or threaten separation from a loved one. This view explains why a death or other kind of loss may trigger agoraphobia. It also may explain why some agoraphobics can venture out when accompanied by a spouse, child, or friend.


LEARNING THEORIES
Psychoanalytic theory from Freud to the present day has given some role to learning as a necessity for the development of abnormal anxiety states. Another school of thought puts learning squarely at the center in its theory of anxiety. In the simplest learning model, an individual may learn fear through direct experience (e.g., being bitten by a snake) or indirectly by witnessing injury to someone else, by observing fear reactions of others, or by being warned of an object's dangers. More likely, however, the reaction is the result of an association between an unpleasant, fearful response and the chance presence of the object that later is viewed as threatening. As early as 1920, one experimental psychologist showed that a young boy could be trained to fear a harmless white rat if frightened by a loud noise every time the rat was nearby. Because the adult with a phobia seldom remembers such an event, the fear seems unreasonable.

Knowledge about learning also sheds light on the possible way in which agoraphobia develops. As with simple phobias, the person who first experiences panic attacks in the presence of a certain set of circumstances - alone in a crowd, for example - may learn to associate awful sensations of panic with all crowds. Repeating the experience, or anticipating it, may reproduce the feeling of threat. Avoiding crowds reduces the discomfort. Because the avoidance behavior is rewarded, the person is more likely to avoid crowds in the future. Avoidance also reduces the opportunity for the person to test whether crowds actually do cause panic. By foregoing this kind of potentially corrective experience, the person further strengthens the phobia.


BIOLOGICAL THEORIES
Observers studying anxiety, including Freud, have long predicted that the brain and the central nervous system would be found to be functioning abnormally in patients with serious anxiety disorders. Their predictions remained speculations, however, because they were limited by the methods and knowledge of their times. All that has changed. Because of recent technological advances, much of the research now being done on anxiety and related disorders focuses on the brain. Biological research workers also attempt to understand anxiety disorders by experimentally producing anxiety in human beings and other animals. Others look for physical symptoms that often accompany phobias or panic to see if they may play a role in causing the disorders.


THE BRAIN AND CENTRAL NERVOUS SYSTEM
In light of what scientists would like to know about the role of the brain in anxiety disorders, this work has just begun. Research on neurotransmitters, the chemicals that carry messages from one nerve cell to another, has not found serious malfunctions associated with anxiety. But indirect measures suggest some abnormalities, particularly in the neurotransmitters norepinephrine, GABA, serotonin, and possibly adenosine.

Scientists are, however, still far from being able to say whether faulty brain function reflects the Cause of anxiety disorders - some genetic fault coded into the person's hereditary apparatus, for example. Experts disagree about the meaning of some research findings. Much of the work, for example, has focused on the brain's processing of drugs that reduce anxiety. Such work suggests, but does not prove, how the brain functions during episodes of severe anxiety. Another problem so far has been that most research necessarily is confined to animals; whether the results apply to human beings is not certain. Pieces of the neuroscientific puzzle have been found, and they are beginning to fall into place.


EXPERIMENTAL "ANXIETY
Investigators have identified several substances over the past few years that can actually produce panic attacks in people who have already experienced them (but not in people who haven't). This line of evidence suggests that patients who are subject to panic attacks may be biologically different from other people. It also offers clues to just what those differences might be. The ability to induce panic attacks gives research investigators a powerful tool for understanding them.

The most thoroughly studied of these anxiety-producing chemicals is sodium lactate. The use of this substance to induce panic attacks is based on the observation that some people who suffer extreme episodes of anxiety produce an excessive amount of the chemical lactate after routine exercise. For these people, exercise can actually set off a panic attack. Researchers have found that sodium lactate triggers panic attacks in a full 80 percent of patients with panic disorder, but in less than 20 percent of normal people. Lactate infusions may provide a means of suggesting which patients are biologically prone to panic attacks and thus apt to respond to drug treatments. It is unlikely, however, that lactate infusions will ever be a sure test.

Although less intensively studied, caffeine is another substance that can produce panic attacks in susceptible persons. Caffeine, of course, is common in coffee, tea, cola, and other soft drinks, and many other foods such as chocolate. About half of panic disorder patients have panic experiences after consuming caffeine equivalent to four or five cups of coffee. (Normal people also experience panic, but only after they ingest much higher amounts of caffeine.) Caffeine is thought to produce its effects by blocking the action of a brain chemical known as adenosine, a naturally occurring sedative. Clinical investigators have found that many people with panic attacks avoid caffeine after noticing that it causes attacks.


A SAMPLING OF OTHER BIOLOGICAL STUDIES
Other types of biological research are also under way. One of the oldest experimental approaches tests physiological responses - for example, heart rate, blood pressure, sweating, or characteristics in the skin. Another type of research examines the role of hormones. But none of these studies has as yet been integrated with what is being learned from studies of the neurotransmitter systems in the brain.

Several studies have shown that patients suffering from agoraphobia and panic disorder have different physiological reactions to fear-producing stress than the average person has. Differences of this type may be present from birth and may explain why some individuals are more susceptible than are others to anxiety disorders.

Several years ago, a number of investigators reported that some agoraphobic patients have a mild heart condition known as mitral valve prolapse or MVP. Like agoraphobia itself, the condition tends to run in families. MVP can give rise to heart palpitations, which some experts believe might trigger panic attacks. It is also possible, however, that chronic anxiety and panic attacks may produce MVP or that both panic attacks and MVP may be symptoms of an underlying nervous system disorder. Finally, it still remains unclear whether there is any difference in the frequency of mitral valve prolapse in panic patients when compared to the general population.

Malfunctions in the thyroid gland have been reported in about one in ten patients who are prone to panic attacks. The relationship between these conditions, which can also cause heart palpitations, and panic is still in the early stages of investigation.

Because breathing difficulty is a hallmark of panic attacks, research scientists have recently become interested in hyperventilation, a condition marked by rapid breathing. The symptoms are similar to those experienced sometimes when blowing up a balloon: dizziness, inability to pay attention or concentrate, and tingling sensations around the mouth and fingers.


ANXIETY AS HERITAGE
The role of history - as recorded in our genes, passed on through our cultures, or learned in our families - is also under study. Barely under way are attempts to learn the relative contributions of nature and nurture to the development of phobias and panic disorder. Some investigators are studying families, because phobias and panic are more common in the relatives of patients than in the general population. Whether this tendency is inherited - passed on genetically - or learned by growing up or simply living close to other anxious people is not known, although some evidence suggests that the link is at least partly genetic.

Clues to what causes anxiety disorders also come from naturalistic observations of animals and human societies very unlike our own. Something like a phobia seems to occur in many animals. Some dogs who have never been touched by anything but a loving hand will cower and slink away at the sight of a broom. Their fear, as well as the common human fear of snakes, may hark back to some earlier stage in evolutionary development. In human societies, cultural differences seem to produce surprising variations in anxiety disorders - the age at which they begin, the course they follow, the symptoms, the distribution among different social groups, the source of anxiety, the experience of the emotion, and the consequences in the life of the sufferer.

Some fears are shared across cultures, suggesting that they enhanced the chances of surviving in the evolutionary history of the human race. Most phobias are directed toward a relatively small number of objects and situations, though there is no reason to believe that these items cause unpleasant experiences more frequently than many others. Phobic fear of truly dangerous electrical outlets, for example, is rare, while fear of seldom-encountered snakes and harmless insects is common. People in our culture are more likely to receive a shock from an outlet than a bite from a snake or one of these insects.

Scientists have sought to explain this paradox by speculating that humans may have an inborn predisposition to fear certain things. This so-called preparedness theory is consistent with the fact that most common phobias (darkness, animals, etc.) involve objects and situations that date from primitive times and were, in the distant past, serious sources of danger.


THE RESEARCH IN SUM
Despite all the research being done on the anxiety disorders - an activity that has accelerated in the last few years - none of the theories that are tested in the various types of studies is adequate to explain what causes phobias and panic. The explanation is probably not far off, however. As they are now propounded, theories about the causes of different types of anxiety disorders tend to cluster either around psychological and social factors or around biological factors. Simple phobias are usually explained in terms of early experience and learning, while agoraphobia and panic (and sometimes social phobia) are becoming increasingly understood as at least partially biological in origin. Most likely, all phobias and panic result from a mixture of influences, although that mixture probably changes with the type of phobia and individual differences among patients. Many theories reflect an implicit assumption that the more serious disorders, such as panic attacks and agoraphobia, are more likely to have a biological basis than the troubling, but less disabling, simple phobias.