Although researchers don’t know exactly why some people experience anxiety disorders, they do know that there are various factors involved. Like many other mental health conditions, anxiety disorders seem to be a result of a combination of biological, psychological, and other individual factors.
How we think and react to certain situations can affect anxiety. Some people may perceive certain situations to be more dangerous than they actually are (e.g., fear of flying). Others may have had a bad experience and they fear this will happen again (e.g., a dog bite). Some psychologists believe that childhood experiences can also contribute to anxiety.
Researchers know that problems with brain chemistry can contribute to the development of anxiety disorders. Certain neurotransmitters (chemical messengers) in the brain involved in anxiety include serotonin, norepinephrine, and gamma-aminobutyric acid (GABA). Researchers have also shown that changes in activity in certain areas of the brain are involved in anxiety. Many anxiety disorders run in families and likely have a genetic cause.
Certain medical conditions such as anemia and thyroid problems can also cause symptoms of anxiety. As well, other factors such as caffeine, alcohol, and certain medications can cause anxiety symptoms.
Traumatic life events such as the death of a family member, witnessing a death, war, and natural disasters such as hurricanes and earthquakes may trigger anxiety disorders.