An Anxiety (or Panic) attack is an abnormal and irrational state of panic about a trivial thing or situation, or in some cases, for no discernible reason at all. Attacks usually occur without warning and a sufferer can simply burst into a state of fear.
It is a disproportionate reaction to the situation or the problem at hand, leaving the person excessively fearful, or sometimes incapacitated, which can affect life generally, relationships, happiness and peace of mind.
The trigger for an Anxiety attack is created initially by a traumatic experience, sometimes though, the sufferer may have no recollection of that experience being traumatic. i.e: One of the most popular causes of a panic attick attack is arogaphobia (an extreme or irrational fear of open, or public places). The traumatic experience may have been that they were scolded by their Mother while they were playing in the park and the sub-conscious has chosen the environment as the cause of the trauma.
The next time the sufferer is taken to the park (or any other open, or public place) they suffer a panic attack.