The Vicious Cycles of Depression

There are plenty of theories about what causes depression.  And many of them overlap with each other in some of their concepts. But here is another theory, one that is often in my mind as I am treating patients.  It is not necessarily different from other existing theories, but it has a somewhat different emphasis.

It seems to me that depression is an illness involving numerous vicious cycles.  Event A leads to Event B, which leads back to more of Event A, which leads to more of Event B, and so on.  There are a variety of these cycles in depression.  If there was just one, it would be easier to treat.  But there are several, and each keeps perpetuating itself. 

The theory doesn't really address the issue of what starts depression in the first place.  But it does help explain how a mild depression can turn into a severe one.

Here are some of the vicious cycles which I see in the depressions my patients struggle with:

Cycle #1--Withdrawing from the World.  Depression increases passivity and decreases social interaction.   This in turn isolates the person and deprives them of interpersonal stimulation. They don't get the social support and distraction from negative thoughts which they would otherwise get from interpersonal relationships.  They are increasingly left alone to deal with negative thought distortions on their own without any corrective input from non-depressed persons.  This in turn increase depression.  Which increases social isolation.  And so on.

Cycle #2--Negative Thinking.  Depression increases negative thinking about self, world, and future. The increase in negative thinking increases the depression level. The more depression a person has, the more negative thoughts are generated in the brain.  This is the basis of cognitive therapy. The cycle of negative thinking to depression and back to negative thinking has to be interrupted.

Cycle # 3--Possible Negative Effects on Nutrition.  Depression often decreases the appetite, which in turn may be depriving the person of important nutrients relevant to mood, well being, and health, thus increasing depression, and so on.  The depressed person may opt for a high carbohydrate (high sugar), junk food diet because they don't want to eat, or don't feel up to cooking a more balanced diet.  They seek out foods that will medicate their immediate feelings, not foods that will provide good nutrition for their brain.  Lacking good nutrition, the brain may be more susceptible to depression.  The link between nutrition and depression has not been proven, but there are some studies suggesting that there may be a connection.

Cycle #4--Decreasing Assertiveness.  Depression  makes people less assertive and less likely to use good problem solving techniques.  When people are less assertive, they don't get their needs met.  Aggravations in their environment can continue unabated.  Problems pile up.  And depressed persons generally do not follow well thought out problem solving approaches that would be needed to deal with the stresses they face.  The ongoing presence of stresses keeps them depressed.  The lack of assertiveness and/or problem solving allows stresses to get worse (such as by building up finance charges on credit cards), which can make the person more depressed.  And so on.

Cycle #5--Downward Spiral of Physical Activity.  Depression makes people less active, which means that some of the benefits of exercise (e.g., brain derived neurotrophic hormone and so on) are not obtained.  (Neurogrowth hormone is a naturally occurring substance in the brain which helps nerve cells grow.)  Theoretically, nerve cell growth or regrowth in the brain may be necessary to recover from depression.

The lack of activity also means that the depressed person is deprived of positive environmental stimulation (lights, sounds, tastes, etc.)  Even though these stimuli may be less interesting and less pleasurable than when the person was non-depressed, they may still give some pleasure, and these may be almost totally absent as the person withdraws into their house and/or room.

Cycle #6--The Cortisol Loop.  Psychological stress causes increases in cortisol.  Cortisol has a negative impact on brain function, although we are not sure all of the different ways this may affect it.  The impact of cortisol on the brain (or of other stress related chemicals)  may then cause the brain to go into deeper depression.  Which causes more negative thinking, less energy, and so on.  And so on.

Cycle #7--A Lowering Availability of Mental and Physical Energy to Cope with Stressors.  Let's say a person goes into a mild depression. This reduces their energy and likely increases their negative thinking about how much they have to do. A molehill starts to seem like a hill; a hill starts to seem like a mountain; a small mountain starts to seem like a big mountain.  There is a perceived difference between what they have to do and overcome on the one hand, and how many resources they have for the task.  The person may get an overwhelming feeling of, "I just can't do it all." This is not just a thought process. It is visceral--felt in the gut. They see their tasks as overwhelming, but they also feel it to be overwhelming because they are so fatigued due to the depression.

These vicious cycles all have the capacity of deepening depression to moderate or even severe levels.  For that reason, intervention can be needed to help someone recover. 

In other cases, depressed persons may succeed in eliminating the external source of stress.  That is, if they are without a job, they may succeed in getting another suitable position.  In still other cases, time may cause the external stress to seem less important.  If we lose a job today, it may feel overwhelming, but in two years, it may seem much less important.

Whatever the reason, the vicious cycles of depression fortunately do not go on forever for most people.  If, on the other hand, a person's depression does seem to be going on and on without any let up, then it would be logical to bring in an outside influence such as a psychotherapist, to help break up the cycle.