The brain is an immensely complex creation of our God that we are just beginning to gain insight into. No one but He fully understands how this spongy blob of tissue uses chemicals and electrical signals to run our body, interact with the world, and connect with the spiritual dimension of creation.
The function of memory alone is astounding. How is it that stored in liquid and electricity we can recall vivid remembrance of sights, smells, sounds, tastes, and feelings from decades ago?! While there is much we do not understand about the brain, modern medical research has brought some insight that has proven helpful.
Research suggests that when our brain is lacking the adequate supply of certain chemicals it needs to function correctly, we experience symptoms of depression. We all experience periods of depressed brain chemistry at different times. Usually our brain is able to make adjustments to course correct and get things back in order.
Sometimes it cannot. For one reason or another, when a brain is not able to make adjustments to get its chemistry back in healthy ranges, it can get stuck in a depressed state and continue to sink deeper. When this happens, we call it “Major” depression.