My fellow neuro-enthusiasts!
I have a special post for you this time☺. We have received a special request to explore the issue of phobias. In the interest of turning the world into neurogeeks we must deliver. That and we are suckers for a pretty face.
Have you or a “friend” let out a childish, high-pitched squeal as a response to simply viewing a multi legged creature? Well, you or your “friend” can rest assured that you are not the only one. The intense dislike for anything creepy crawly starts after the age of 7 in females and 12 in males (based on personal observations, boys like icky things). Lots of people (yes very scientific) don’t enjoy our multi legged friends. Of course, there is a percentage of individuals that don’t simply “dislike” them, they fear them. A deep, sometimes irrational, and immense fear. Scientifically known as phobias.
Phobias are morbidly intense and are at times debilitating to the individual. According to the American Psychological Association, more then 10 million people in America suffer from some sort of phobia. There are a multitude of different types of phobias that all involve intense emotional and behavioural responses, these phobias are not limited to our little friends, but encompasses every aspect of our lives. From fear of crossing the street, to fears of insanity and pointed objects.
So naturally we are asking what is happening in the brain? Why is it that some people have such a heightened responses, sometimes quite ridiculous, to these creatures? What is it in their brain that makes them respond so strongly? Due to the nature of phobias, research is usually based on cognitive neuroscience techniques.
So to answer the above questions, researchers have utilized different types of brain imaging techniques to visualize what is going on in the brain during the exposure of the fear-inducing object. For example functional magnetic resonance imaging (fMRI) is a scan that measures the change in blood flow activity in the brain. Researchers use it in both humans and animals due to its lack of invasiveness, wide availability (if your lab is loaded), and pretty pictures. The brain activation in phobia is highly dependent on the type of phobia it is. For example, those you have a fear of social situations will have different areas of the brain activated in comparison to those who have a fear of spiders. Individuals that experience social phobia show a decrease in brain activity in the amygdala, our friend the hippocampus, and the parahippocampal gyrus. Those who are arachnophobic (fear of spiders) have a decrease in activity in the insular cortex, thalamus, dorsal anterior cingulate cortex and the parahippocampal gyrus.
What’s so cool about these studies is that they will provoke the fear, for example showing images or videos of the spiders while the individuals are in the fMRI. The researchers can then map out the activation of the brain areas before the exposure, during, after and finally in response to different types of treatments.
A particular study by a group from Cambridge explored the physical distance between the feared object and the individual. They found that when the “threat”, they used tarantulas, was close, there was an increase in fear related brain networks, which includes the areas we have mentioned above. As the threat was removed they found that the orbitofrontal cortex became activated. They have suggested that this engagement may be suggesting that this region may be involved in the relaying the “safe” signals.
Due to the individualistic nature of phobias it is understandable that finding a single mechanism that is responsible for the fear may be difficult, if not unreasonable.
‘till next time,
P.S. Neurobites will be involved in a variety of social events..
Yes we have friends. And no they are not only in our heads.We will prove it with photo posts.So there:P.
Look out for the following posts;
Neurobites on location for Brain Awareness Week
Neurobites on location at a student conference
Neuronbites on location at a public neuroscience lecture.