For the last several hundred years the fields of behavior, psychology, and psychiatry had little choice but to rely on descriptions of events – behaviors – when making a diagnosis. The brain has been seen as a “black box” – a mystery of subtle activities. Anatomists of the middle ages threw out the brain – because it didn’t seem to do anything – although its location might have been a clue that something was going on in there. Indeed, there is much going on in there! Major shifts are occurring not only in the views of behavior disorders but also in their treatments.
In about 1640 René Descartes opined about the brain and behavior in ways that were consistent not only with the knowledge of the times but also with the allowable constructs of the times. Fresh on his mind, no doubt, was the fate of Galileo Galilei, who offered that maybe the earth wasn’t the center of things. Galileo’s ideas, though founded in science, put him in confrontation with a church threatened by ideas. They were willing to burn him at the stake as a heretic if he was not willing to recant. He did. (He died in 1642.) So, when Descartes – a very smart guy – approached the issues of brain and behavior he concluded that they must be separate. There must be a brain that was subservient to an etherial mind. That detached “mind” allowed for a “spirit” – and the powers that be were happy. He spawned what has become known as “The Cartesian Duality”. He did not offer an explanation of how the separate mind and brain would factually communicate. However, this was 1640.
Now we are in a different era. Our studies of this era are beginning to show precisely how the mind is a derivative of the brain. With fMRI we can actually watch thought happening. We are building a picture called “The Connectome” which shows how the areas of brain are connected and relate to each other during activities of thinking [https://en.wikipedia.org/wiki/Connectome] Much is still not known. But we do now know precisely where to look for the mind.
In this era we begin to leave behind the obligations of past centuries. No longer are we obligated to talk about behavior only in behavioral terms. Now we are understanding the physiology of behavior. We can begin to discuss both behavioral health and illness in terms of physiological states and processes. We begin to leave behind illness labels based only on constellations of symptoms (constellations that often vary over time, or be similarly represented in other illness). We are now moving into the era where psychiatric/psychological diagnosis will be based on measurement of biological states. Most certainly, we are in the early stage of this transition. There is still a lot of reliance on symptoms. However, we can and should be trying to understand illness and health beyond symptoms. We need to arrive at causes and mechanisms. This shift will be of great benefit to patients. Many patients experience the problem of receiving different diagnoses from different providers (at any one time, or over time). As we shift to diagnosis based on objective measurements this degree of variability will shrink. Further, as we develop better objective tests for diagnosis we will have better tracking tools to objectively determine whether treatment is beneficial or not (short term, and long term).
This is an active area of interest and a “moving target”. The “state of the art” is rapidly changing. Below, I’ll list some references here that may give you an idea of where we are. Over time the list and the commentary will evolve.
“Depression” is a widely used word, often with imprecise meaning. The following 2010 article discussed the state of perspectives on “depression” at that time. It’s a medical article. You may not want to wade through it. However, you can just get a sense for the variations in perspective. Most importantly, not all patients with “depression” have the same thing. Appropriate treatments will vary.
More recently, here is a 2017 article that discusses the variable mechanisms that may be present in depression.
Similarly, “anxiety” is a word used frequently – often with little precision. Many situations cause the behaviors of anxiety. The following article is hampered by an excessive number of ads. However, it is written for the general public and has some good generalizations.
Further, here is a quick review of anxiety disorder as put out by the National Institutes of Mental Health (great: not many ads!)
I’ll be adding to this list and also adding more discussion.