Because of the length of the article I have broken it up into several sections for you. I hope you find this information helpful, and as always, welcome your questions and comments.
The Body/Brain Connection in The Conditioned Fear Response (Part 1)
Imagine this - you're out with a group of friends, having a good time, talking, laughing, and listening to music as your friend at the driver's wheel takes you to your party destination across town. Because your attention is diverted by the conversation at hand, you are only vaguely aware of certain physiological changes taking place in your body, and a mild uneasiness occurring psychologically. It manifests itself at first by a mild queasiness in your stomach, but then it becomes an inexplicable sense of anxiety and fear that you cannot explain. You can't ignore the tremor in your hands and the sudden headache and increase in your respiration rate, though it obviously has nothing to do with your friend's last joke! What in the world is happening? you ask yourself. You begin to look around you; you take note of your surroundings and the location of the car you're traveling in. Then the realization hits you; you know this place! You've been here before! Your heart is pounding now... Step away from this little scenario now and look on from an objective distance. The person inside the car is someone else. What would it be like if we could look inside that person's brain, especially in the area immediately surrounding her midbrain? What we would see is a whole range of activities taking place! There in an area most commonly referred to as the Limbic System we would see a fascinating array of processes most likely responsible for what she was feeling. It could be explained by a paradigm called Pavlovian Fear Conditioning.
First, what is fear and why do we feel it? What purpose does it serve? Surely, it must serve more than some trivial function when we see all the intense reactions the body has to it. And why does it cause such long lasting physiological changes? According to LeDoux (1998), "Fear is a normal reaction to threatening situations." But the effects of fear do not simply disappear when the danger does. Somehow, the memories of those fear-producing experiences seem to be recorded in our very neurons! And so they are, literally. Understanding the "behavioral correlates of fear" (Malenka & Nicoll, 1997) may bring us a clearer understanding of how the mechanisms of fear and fear conditioning contribute to survival.
