mental disorders making us feeling fearful are called anxiety disorders.Worrying about future events is called anxiety.These events cause increase in heart rate and nervousness.
They include various disorders selective mutism(an anxiety disorder in which a persob cannot speak in specific situations),panic attacks(sudden attack of intense fears),separation anxiety disorder,social anxiety disorder,specific phobias.
causes can be genetic or environmental.
There are also other risk factors like poverty,abuse and family history.
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