Today I woke up feeling exhausted. Every time this happens, I just want to take something that will boost my mood into a unreasonable "work high". I vaguely recall reading about the medical cause of depression, where I learned that our moods are affected by some enzyme in our brain. So I thought maybe the level of that-whatever-it-is thing in my head is highly variable. Maybe there is a way to stablize it (doing Yoga maybe?).
So I went online and googled.
Okay. It is not really an enzyme. Hippocampus (hippo-campus?) that in charge of memory storage becomes smaller in depressed patients. Hmm ... interesting, I thought. Most people had depression went through things they DO want to forget. Sometime, we hear ourselves saying "I am trying to forget about this" especially during stressful events. This can be interpretted as signals to our brain (of course, we think using our brain, don't we?) and our brain takes the hint and signaled the hippocampus to become smaller.
There is absolute proof that people suffering from depression have changes in their brains compared to people who do not suffer from depression. The hippocampus, a small part of the brain that is vital to the storage of memories, is smaller in people with a history of depression than in those who've never been depressed. A smaller hippocampus has fewer serotonin receptors. Serotonin is a neurotransmitter -- a chemical messenger that allows communication between nerves in the brain and the body. What scientists don't yet know is why the hippocampus is smaller.
Investigators have found that cortisol (a stress hormone that is important to the normal function of the hippocampus) is produced in excess in depressed people. They believe that cortisol has a toxic or poisonous effect on the hippocampus. It's also possible that depressed people are simply born with a smaller hippocampus and are therefore inclined to suffer from depression.
So we probably should keep remembering everything no matter how frustrating it is. :)