Understanding the "Understandable" in "Understanding Depression"

A twitter thread by Dr. Gipps prompted me to look at the use of the term "understandable" more closely in the document "Understanding Depression" by the British Psychological Society. It appears to me that the term is used in an ambiguous and polysemous manner in the document, drawing on multiple themes and analogies, that are not only different but also generate different implications and subsequent questions. In this post I identify some of the different ways in which this term is used. A recurrent theme in the document, at least implicitly, is that depression being "understandable" poses some sort of a problem for a medical approach to depression; there is a crude sense in which it can be the case, but not necessarily. I briefly discuss this aspect of the problem as well. 

1) "Another idea is that, rather than being an experience thrust upon us by biology, depression, like other emotions, is often an understandable human response to the world around us that involves complex evaluations of events." Understanding Depression (p. 23)

The document appears to be offering emotions as the template of "understandability" in this particular instance

The APA dictionary defines emotions as:

"a complex reaction pattern, involving experiential, behavioral, and physiological elements, by which an individual attempts to deal with a personally significant matter or event. The specific quality of the emotion (e.g., fear, shame) is determined by the specific significance of the event. For example, if the significance involves threat, fear is likely to be generated; if the significance involves disapproval from another, shame is likely to be generated. Emotion typically involves feeling but differs from feeling in having an overt or implicit engagement with the world."

So "understandable" in this sense would imply

- the presence of an experiential element (along with physiological elements)

- it is generated in response to or as a way of dealing with a significant matter or event 

However, this statement in the document also implies that experiences that are "thrust upon us by biology" are not "understandable." This is a somewhat odd thing to say given the embodied nature of emotions. Presumably, this refers to a biological cause along the lines of neuropathological processes such as tumors. This does generate a problem because as all physicians are well-aware, brain lesions can influence our emotions, depending on their location. Emotions of all sorts can be exaggerated or distorted in problematic ways due to brain diseases. Do emotions stop being "understandable" if they have been influenced by biological processes in this manner? I suspect the authors of the document may say "yes" but this means that there are assumptions being made around the use of understandable that go beyond any simple analogy with emotions. These assumptions have not been clearly articulated, which makes any critique difficult. Nonetheless, this brings up the dilemma of emotions being abnormal in some sense, yet still simultaneously understandable in another, a dilemma that "Understanding Depression" doesn't quite seem to appreciate. 

Another issue is that emotions are also a response to a wide variety of psychological ways in which the interactions with world have been "internalized" during the course of our development. The ways in which our interactions with others has generated, say, a sense of deep insecurity, of being unlovable, or being inadequate, etc. Emotions that are generated in response to such psychological conflicts can ultimately be traced back to an interaction with the world at some point in development, but it would be a mistake to think that these emotions are a response to a world here and now; rather, they are a response to a world that once was, and now exists deep inside us. I don't think the document fully appreciates these dimensions of the analogy with emotions.


2) "Many life events and circumstances can lead to depression, particularly ones involving threat or loss. It is common, natural and understandable to feel low and hopeless if faced with a situation of ongoing threat in which we have little control, for example a life-threatening illness,  discrimination, financial problems, violence in a relationship, exploitation, bullying or homelessness." (p. 30)

The use of "understandable" here is not fully discernable, but it appears to be along the lines of "typical" or "it is to be expected."

This meaning of understandable also has analogues in medicine. Obesity can be an understandable (i.e. typical, or expectable) response to poor diet, stress, sedentary lifestyle, and social practices that make healthy food inaccessible to many. Therefore, this sense of "understandable" doesn't divorce depression from the realm of medicine in a way that the authors of the document may like it to be. 

3) "A key message of this report is that depression is a very difficult but common human experience, but also an understandable one. In particular, it highlights how the events and circumstances of our lives often play a powerful role; countering the misleading but widespread idea that depression is usually the result of something going wrong in the brain." (p. 39) 

"Understandable" here appears to be appealing to a sort of causality; depression is a result of, is caused by, circumstances of our lives, rather than something going wrong in the brain. That is, the connotation is that of psychosocial etiology.

If such an etiological interpretation is correct, this brings up other sorts of concerns, given that etiology of depression in clinical settings is typically complex, multifactorial, and involves multiple levels of explanation.

4) "The most important message of this report is that depression is not a disease but a human experience: a complex, understandable set of psychological responses to the events and circumstances of our lives. It is understandable in both evolutionary and psychological terms and has a function: it often tells us that things need to change in some way." (p. 51)

The use of "understandable" here is clearly polysemous; there are the prior themes of response to the world and etiology, but it goes further and says that depression is understandable in "evolutionary" terms and serves an evolutionary function of telling us that something needs to change. The idea is that depression is an evolutionary adaptation. This sense of understandable in evolutionary terms is quite broad and overlaps greatly with evolutionary adaptations of other sorts in medicine. Consider, for example, this discussion by Randy Nesse and Dan Stein about how evolutionary perspective informs the medical model: 

* "Physicians in other medical specialties routinely distinguish direct manifestations of bodily malfunction from symptoms that are normal protective responses. Seizures, paralysis and dyskinesias arise from abnormal bodily mechanisms. Cough, pain and fever, by contrast, are normal protective responses shaped by natural selection in conjunction with regulation systems that express them in situations where their benefits are likely to exceed their costs...

Capacities for anxiety and mood also exist because they offered selective advantages to our ancestors. Emotions adjust diverse aspects of physiology, cognition, behavior and motivation in ways that increased ability to cope with situations that influenced fitness during our evolutionary history. Their utility is confirmed by the existence of systems that regulate their expression; such systems could evolve only if the responses were useful in certain circumstances...

Defense regulation systems can fail, giving rise to responses that are abnormal in any circumstance. Most defensive responses are aversive, so their inappropriate arousal causes much suffering. High prevalence rates for chronic pain, chronic fatigue, anxiety disorders and depression suggest that the regulation mechanisms underlying cognitive/emotional symptoms are especially vulnerable to failure. Most such failures are not complete but involve responses that are too soon, too strong or too prolonged for the situation."  *

"Understandable" in evolutionary sense, therefore, views depression as analogous to cough, pain, fever, and other evolutionary adaptive responses. However, evolutionary responses can fail, or these responses can be inappropriately excessive or prolonged in relationship to our present context, hence, this use of understandable is entirely compatible with depression being abnormal yet understandable in the same sense as cough or pain may be abnormal yet understandable. Again, I don't think this implication is fully appreciated or articulated by the document.