What Can A Cause Panic Attack

physiology of panic attacks 

One clue to the physiology of major panic attacks is the common symptom of rapid, heavy breathing (hyperventilation). This kind of respiration has the biological function of absorbing oxygen quickly for emergency purposes.

The reaction of oxygen with the body's cells produces carbon dioxide, which is then exhaled. During hyperventilation the lungs may exhale more carbon dioxide than the cells produce, causing the level of carbon dioxide in the blood and brain to fall.

The resulting symptoms, which may temporarily include dizziness and heart palpitations, caused some people to breathe even harder, further dissipating carbon dioxide and intensifying their severe panic attack. 

Paradoxically, inhaling air with a high concentration of carbon dioxide may cause similar panic attack symptoms. This finding has inspired the controversial theory that during a panic attack the brain is falsely signaling a shortage of oxygen or an increase in carbon dioxide and setting off a suffocation alarm in a person with a low threshold.

Because both excess and shortage of carbon dioxide are associated with panic, most experts are inclined to believe that a panic attack may occur in a susceptible person who develops any imbalance of gases in the blood sufficient to cause intense physical sensations.

Another physiological clue is derived from injection of the chemical sodium lactate, which also produces the physical symptoms of panic attacks. These symptoms precipitate panic itself in about four-fifths of people with panic disorder but only one-fifth of the general population.

The muscles of the body produce lactate (in the form of lactic acid) during vigorous exercise, and its presence is a sign that the body is straining to meet oxygen needs. Lactate sensitivity might be a sign of genetic susceptibility to panic attacks, since it is often found in otherwise healthy members of the families of people with panic disorder.

Fearing Fear Itself

Experiments with carbon dioxide and lactate show that the physical symptoms of a panic attack do not always lead to the fear of fear itself that characterizes panic disorder.

Most people also find it easy to adapt physiologically and psychologically to hyper-ventilation, and panic is largely unaffected by the beta-blocker propranolol (Inderal) and other drugs that usually block anxiety-induced physical symptoms.

Something else must convert the biological response into a psychiatric disorder. One widely accepted view is that panic occurs when the physical sensations are wrongly interpreted as a sign of impending loss of control, death, or insanity.

In fact, some experiments in which patients inhale excess carbon dioxide suggest that they are less likely to panic when they are induced to think mistakenly that they can control the amount they are inhaling. If this view is right, panic disorder resembles hypochondriasis, except that the misinterpreted physical sensations are briefer, more sudden in onset, and more limited in variety.

If catastrophic misinterpretation explains panic attacks, it is unclear why people go on fearing them even after repeatedly surviving without harm. One possibility is that they are never sure the next one will not be different, a genuine heart attack or psychotic episode; some may suffer from the opposite of the gambler's fallacy and think their luck is due to run out.

Another objection to the misinterpretation theory is that some panic attacks are not even accompanied by conscious fear. Misinterpretations might occur automatically and almost unconsciously, but then it becomes unclear what to count as evidence for their existence.

A close watch

Some people may be susceptible to panic disorder because they are unusually sensitive to physical symptoms of anxiety. There are studies suggesting that panic patients are skilled at detecting subtle changes in heart rate, breathing, and other physiological rhythms.

The problem is that sensitivity to anxiety symptoms might be a result rather than a cause of panic attacks. But experimental volunteers with high anxiety sensitivity and patients with panic disorder respond similarly to hyperventilation and sodium lactate.

One kind of pattern leading to panic might be the following: the irrational thought that a tunnel will collapse while you are driving through it evokes an image of suffocation, which causes chest tension and a pounding heart.

These are seen as signs of an impending heart attack and exacerbate the anxiety, which heightens the physical tension, and so on. Thinking errors and the associated sensations and feelings reinforce one another in a vicious spiral of fear.