Researchers studying the brain may have found the secret to fear.
A new study from the Columbia Medical Centre has identified the part of the brain that controls response to fear.
It is thought that psychiatric disorders such as anxiety or depression could be better understood as a result of the research.
"Based on these findings, tailored treatments may someday be developed based on the biology of the person's disease," said Dr Eric Kandel, one of the study's researchers.
Scientists began to study fear when it was speculated that there must be a specific and distinct neurological response to such events.
"People are exposed to an ever increasing amount of stimuli in our everyday lives and so we realised that the brain must employ a processing mechanism to prioritise and refine responses - we don't run away from every loud sound or unexpected sight," commented the study's senior author Dr Joy Hirsch.
The study distinguished the separate processes at work in arriving at a sense of fear.
First, a stimulus such as a loud bang is registered and then a second region of the brain – the ristral cingulate (rACC) – determines whether an action such as running away is needed or not.