This morning I was thinking
about the relationship between your pre-frontal cortex and your limbic system.
I know, it’s a little strange to be having these thoughts while out riding a bicycle in the morning… a hazard of the profession I guess.
The reason I was thinking about this subject is that people’s moods appear to be affected by both of these areas of the brain.
The limbic system is the source of emotion and, perhaps, a part of the unconscious. You might think of it as Freud’s “id”, the animal part of the brain, the part that acts quickly, figures out very rapidly if things are safe or not safe, sees the big picture but is likely to misinterpret.
The pre-frontal cortex is the evolutionarily newer part of the brain that is where most conscious thought takes place. It is where we think through problems and try to figure out meanings and reasons for things. Both of these structures are very much affected by mood, and in turn, affect mood. The limbic system is where all of the monoamine neurotransmitters like dopamine and norepinehrine and serotonin are stored. These are the brain chemicals that are affected by most antidepressants. They set the emotional “tone”. If you wake up one day and for no reason at all your mood suddenly becomes much more cheerful, you can probably thank your limbic system.
On the other hand, the pre-frontal cortex, particularly the part of the pre-frontal cortex that is in the midline of your brain, is very much involved in assessing risks and looking for potential catastrophes. The extent to which you are inclined to look for risk or negative outcomes is probably largely determined by your genes and your early childhood experiences, but you can affect that tendency through conscious choice.
In other words, you might have a natural tendency to look for potential negative reactions from others, but you can consciously shift your attention towards other aspects of the situation by paying attention, for instance, to how people are interacting with each other rather than what their reactions are to you.
This ability to shift attention is the basis for psychotherapy. By getting us to switch from risk thoughts to more positive or less negative thoughts, our mood can gradually change. In other words, the pre-frontal cortex, our conscious mind, can affect our limbic or emotional brain.
While I was riding my bicycle I was thinking about a couple of pretty depressed folks that I was going to be seeing in the morning. My eyes were downcast, I was mentally anticipating possible disasters. Then it occurred to me that I hadn’t actually looked at the scenery. I was so immersed in those worry thoughts that I was missing the beauty of the lake, trees, and flowers I was cycling through.
The ability to focus attention is a lot of what makes us able to change our mood… look around and see if you have been missing something interesting, or positive, or beautiful.