Depression and the injured brain
Prozac, the antidepressant, is one of the most successful drugs in history. It has been prescribed to more than 54 million people worldwide and has relieved massive amount of emotional pain and suffering. It initiated an industry of medications that focus on increasing the amounts of serotonin in the brain. Serotonin is a neurotransmitter, a chemical in the brain that is associated with mood. It was determined that depression was a result of insufficient amounts of serotonin. Sadness became a chemical issue. Happiness was just a matter of providing the brain with what it lacked.
The only problem is that this theory is grossly inadequate to explain Prozac’s efforts. Recent research has demonstrated that lowering serotonin does not make a person more depressed, or less depressed, nor does it make a depressed person more depressed. So what, exactly, does Prozac do?
According to Jonah Lehrer in the Boston Globe, new research has offered a novel theory of depression. Publications in prominent scientific journals have indicated that it is not a lack of serotonin that causes depression, but that the brain is atrophying and dying. Prozac, and similar medications, basically heal these injured neurons and restore them to full, healthy functioning.
“The best way to think about depression is as a mild neurodegenerative disorder,” said Ronald Duman, a professor of psychiatry and pharmacology at Yale. “Your brain cells atrophy, just like in other diseases (such as Alzheimer’s and Parkinson’s). The only difference with depression is that it’s reversible. The brain can recover.”
This new theory is causing radical shifts in the science of the brain. It is shifting focus from symptom oriented explanations of emotional states to understanding the biological, anatomical underpinnings of mood. With the advent of brain scanners and DNA microarrays, some scientists are recategorizing mental health disorders in a manner that patients are not diagnosed exclusively on their most obvious symptoms.
Research has shown
that chronic stress damages the brain by depleting the proteins that nourish and invigorate neurons. According to Duman, “The mental illness occurs when these stress mechanisms in the brain spiral out of control.” This causes the brain to stop functioning, except for the most critical functions. Neurons seem to stop growing and creating new cells.
We don’t want to think of depression as a result of dying brain cells, preferring to think of it as an altered emotional state. But the term “depression” is likely to be misleading and conceals the fundamental nature of the process. Scientists are beginning to pay more attention to the neglected, “vegetative” signs of depression, such as disturbances in sleep, appetite, smell and taste, in addition to problems with learning and e memory. Lehrer states, “Like the paralyzing sadness, which remains the most obvious manifestation of the mental illness, these symptoms are also byproducts of a brain that’s literally withering away.”
Eero Castren is a neuroscientist at the University of Helsinki, who states, “It’s much more than just an inability to experience pleasure.” While antidepressants help brain cells recover their vigor and form new connections, patients must still work to cement these connections in place, perhaps with therapy. In this manner antidepressants are like anabolic steroids, which increase muscle mass only when subjects also go to the gym. Castren states, “if you just sit on your couch, then steroids aren’t going to be very effective. Antidepressants are the same way: if you want the drug to work for you, then you have to work for the drug.” This may explain the predominant scientific evidence that the best treatment for many forms of depression is a combination of psychotherapy and medication. It has been shown repeatedly to be the superior form of treatment over antidepressant medication alone.