Narrator: This is Science Today. While it may not be the most pleasant of senses, fear is there for a reason - to protect you from danger. Dr. Mark Barad, a professor of psychiatry at UCLA says fear is a very old response.
Barad: In fact, it actually predates the vertebrate lineage. A lot of what we know about the molecular components of fear or at least of reacting to bad things happening was learned from the snail! Those molecules are the same molecules that we use for fear. So the molecules that are necessary for learning fear have been the same since snails to us. It's the same molecule - so the anatomy has developed, obviously considerably.
Narrator: Barad has been studying a type of psychotherapy called extinction of conditional fear.
Barad: Extinction is learning to inhibit that fear under circumstances where it's not appropriate. So what we've discovered - at least one of the specific molecules that are involved in that process of learning inhibition, of learning to inhibit your fear, so the original fear remains.
Narrator: For Science Today, I'm Larissa Branin.