The brain is essentially a central processing center for a variety of sensory data that inundates it at all times. One of its principle functions is to sort out what is real and what is only perceived. This is done primarily in the frontal lobes where executive functions reside.
It doesn't always get it right, though. :-)
This is particularly true when there is an anxiety disorder such as OCD or a severe mood disorder such as depression or a psychotic disorder such as schizophrenia. Distinguishing between these disorders can be challenging and often requires a mental health professional, particularly when there is overlap of conditions or conflation of symptoms.
Can you explain why certain cognitions produce certain bodily functions. I read that if one is to picture something vividly, the body will react as if the thought were real. Can the brain differentiate between what is real or imagined? Does the amygdala, for example, know the difference between real and imagined fear or will it trigger the fight or flight response even if no danger is present?
Are there any books that would be useful for a lay reader to understand this? Would basic books on Neurology be helpful, or will books from other fiels of study be necessary?
A couple of final questions:
Is it true one can notice certain physical sensations when one places cognitive attention on them? For example, in people who have OCD with sexual obsessions, they often report a groinal sensation to something they claim they're not attracted to. Is this because they're placing cognitive attention on that part of the body? Are they noticing sensations that always existed but were previously neutral, or are they actually causing sensations? Can fear itself cause arousal?
There was the case I read of an OCD sufferer who actually felt like he would physically strangle his father and had to keep his hands held down. Does powerful anxiety have the power to make someone act against their nature?
My OCD has got much better after CBT with exposure therapy. I still have some problems but cope a lot better. I'm hungry for information and am always wanting to learn.
Thanks for your responses.