Depression Spectrum (Unipolar/Bipolar)

Everyone who goes through a battle with depression has their own unique experience. No two experiences are ever quite the same. However, we are able to see enough similarities that we can identify common categories, or types, of depression. We’ve come to learn over time that depression presents itself on a mood disorder spectrum, with unipolar major depression at one end and bipolar 1 depression at the other end. Across the spectrum, people experience many of the same symptoms, but each type of depression has its own characteristics.

Unipolar vs. Bipolar Depression

The biggest distinction between the two ends of the spectrum is whether or not there is mania present. Unipolar depression is depression (low energy, low mood, hopelessness, etc.) without any mania. Bipolar depression, on the other hand, is characterized by manic episodes (high energy, restlessness, impulsiveness, etc.)

People with bipolar 1 typically have had both depression and mania. During a depressive period, bipolar can look a lot like unipolar depression and may even be misdiagnosed as such at first. However, the presence of even one manic episode differentiates it and makes the bipolar diagnosis clearer. In fact, although a majority of people with bipolar 1 do have periods of both mania and depression, you only have to have had a manic period to receive this diagnosis. In other words, even though it’s on the depression spectrum, some people with bipolar 1 do not experience depression.

Major Depression

At one far end of the spectrum is major depression. When you think of the “classic” form of clinical depression, this is probably what you have in mind. It’s characterized by a depressed mood and/or anhedonia (lack of interest in things) lasting most of the day every day for at least two weeks. Some people live months or even years with major depression, with or without a diagnosis. In addition to the low mood, symptoms of major depression include:

Change in appetite which may result in weight changes; this may go in either direction (loss or gain)
Fatigue, tiredness, persistent lack of energy
Inability to focus, concentrate, think clearly, and/or make decisions
Observable slowing down of thought, speech, and movement
Pervasive feelings of guilt and/or worthlessness

People who have major depression may or may not think regularly about death. They may or may not have thoughts of suicide. Of course, if you have thoughts of suicide, and especially if you have a plan for suicide, it’s important to reach out for help immediately.

Bipolar 1 and 2

As discussed, bipolar disorder is at the other end of the spectrum. A person with bipolar 1 disorder has had at least one period of mania. As aforementioned, they may have also had a depressive period, but it’s not a requirement for the diagnosis.

So, what is a manic episode? It’s a period of hyper-energy, which may manifest in symptoms that appear “happy” to others on the outside but are just as likely to look restless and irritable. Someone diagnosed with bipolar 1 mania has three or more of the following symptoms:

Delusions of grandeur or feelings of unusually high self-esteem
Frequent, rapid speech
High energy, sometimes intensely focused on completing activities or tasks
Insomnia with the feeling that you don’t need to sleep
Lack of ability to pay attention
Racing thoughts
Risk-taking behavior and impulsivity

If a diagnosis doesn’t have to require a depressive period, then why does bipolar end up on the depression spectrum? That’s where it helps to understand bipolar 2. Someone with bipolar 2 has at least one depressive period and one period of hypomania. Hypomania is similar to mania, but the person experiences the symptoms to a lesser degree.

So, in terms of the spectrum, if major depression is all the way to the left and bipolar 1 is all the way to the right then bipolar 2 is just to the left of bipolar 1. Someone with bipolar 2 has had depression symptoms. They’ve also had some of the symptoms of (hypo)mania. Someone who has bipolar 1 is “more” manic and may or may not have had depression symptoms.

Disorders in The Middle of The Depression Spectrum

Once you understand the two ends of the depression spectrum, you can start to see that there are different forms of depression that exist more in the middle. People can have symptoms of depression that aren’t as persistent, so they have a condition that’s closer to that left end of the spectrum but not as far over as major depression. On the other hand, people can have mood changes that put them closer to the right end of the spectrum but not as far over as bipolar. Some of the conditions that exist in the middle of the spectrum include:

Cyclothymia, which has some of the same “highs” and “lows” seen in bipolar but with cycles that last significantly longer. For example, someone might have mild depression for two or more years and then mild hypomania in the years that follow.

Persistent Depressive Disorder, previous called dysthymia, which exists close to major depression on the spectrum. It’s a similar form of depression but one that lasts longer (two years or more). The symptoms may or may not be as intense as they are in major depression because there are various forms of this condition ranging from mild to severe.

Postpartum Depression, which is a period of depression that occurs within the first year of a child’s birth.

Seasonal Affective Disorder, which is depression (often mild) that recurs annually around the same season each year. Most people find themselves affected in the winter months, when natural light is limited) but some people have Reverse Seasonal Affective Disorder with symptoms occurring in the summer.

There are also many forms of depression that take on some of these characteristics but don’t fit neatly into one diagnosis. You can have atypical depression, with strong depression symptoms that are mitigated by joyful experiences. You can have bipolar (Not Otherwise Specified) in which you have many of the symptoms of bipolar disorder but none that rise to the level of bipolar 1 or 2. So don’t be surprised if your own depression symptoms don’t fit neatly into a box. You and your therapist can work together to figure out your place on the spectrum in order to find the solutions that will work best for you.