Mood disorders are a broad umbrella term used for conditions in which disturbance of mood is the central feature. Common mood disorders include different types of depressive and bipolar disorders.
While it is normal to experience periods of different moods, mood disorders are characterized by emotional extremes and difficulties in regulating mood.
Mood disorders are found to affect about 20% of the general population at any given time. Specifically, in the US for instance, 17% of the population is thought to struggle with depression over the course of their lifetime, with bipolar disorders affecting 1% of the general population.
Disclaimer: This article is for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. If you are concerned about your mental health or that of a loved one, please consult a qualified healthcare professional. If you are in crisis or experiencing suicidal thoughts, seek help immediately by calling your local emergency number or a crisis hotline.
Quick Overview of Mood Disorders
| Disorder | Hallmark Features |
|---|---|
| Major Depressive Disorder (MDD) | Persistent sadness, loss of interest, fatigue, feelings of hopelessness |
| Bipolar I Disorder | Cycles of depression and full mania (extreme highs with risky behavior, racing thoughts, high energy) |
| Bipolar II Disorder | Cycles of depression and hypomania (less intense highs than mania, but still disruptive) |
| Cyclothymic Disorder | Chronic mood swings between mild depression and hypomania for 2+ years |
| Persistent Depressive Disorder (Dysthymia) | Long-term, low-grade depression lasting at least 2 years |
| Seasonal Affective Disorder (SAD) | Depression tied to seasonal changes (commonly in winter) |
| Disruptive Mood Dysregulation Disorder (DMDD) | In children, frequent severe temper outbursts and chronic irritability |
| Premenstrual Dysphoric Disorder (PMDD) | Severe mood changes, irritability, and tension before menstruation |
“Affective disorders” vs “mood disorders”:
In clinical literature, these conditions are sometimes called "affective disorders," but today the term "mood disorders" is far more common and user-friendly—it's the phrasing people typically search for in reference to depression, bipolar disorder, and related conditions.
Types of Mood Disorders
Major depressive disorder
Major depressive disorder is characterized by prolonged and persistent periods of extreme sadness.
While it is normal to experience sadness or grief during traumatic life events, if this depression continues even when the events are over, or there is no apparent cause for the sadness, this may be classified as clinical or major depression.
This is a very common mental disorder that is accompanied by a variety of physical, cognitive, and emotional symptoms.
Bipolar I disorder
This disorder is characterized by extreme emotional highs (mania) and extreme emotional lows (depression) that can last for several weeks or longer.
Manic episodes in bipolar I disorder can involve euphoric and/or irritable moods, high energy, being more talkative than usual, and increased self-importance.
Depressive episodes in bipolar I disorder can involve feeling hopeless, lethargic, having difficulty concentrating, feeling worthless, and losing interest in everyday activities.
Bipolar II disorder
This disorder causes cycles of depression which is similar to those who have bipolar I disorder.
Individuals with bipolar II disorder also experience hypomania, a less severe form of mania.
Hypomanic periods are not as intense or as disruptive as manic episodes, and people are usually able to handle daily tasks despite these episodes.
Seasonal affective disorder (SAD)
SAD is a type of depression that only occurs during certain seasons. Typically, depressed symptoms start in late autumn or early winter for many people, less commonly starting in spring or summer for others.
The symptoms of SAD resemble those of major depression, although SAD differs in that the individual will usually start to feel better once the season is over.
Cyclothymic disorder
This disorder causes emotional highs and lows believed to be less extreme than in those experiencing bipolar I or II disorder.
Individuals with cyclothymic disorder experience continuous irregular mood swings for extended periods. The mood changes can occur suddenly, at any time, with only short periods of baseline mood.
Disruptive mood dysregulation disorder
This is a newer type of depressive disorder that was added to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).
DMDD is usually diagnosed in children. It involves persistent irritability, anger, and frequent temper outbursts, often without any clear cause.
Persistent depressive disorder
This disorder was previously known as dysthymic disorder, a milder form of major depression.
This type of depressive disorder is long-term, occurring for at least two years for individuals, and the symptoms of depression occasionally lessen during this time.
Premenstrual dysphoric disorder
This is characterized by significant mood changes and irritability during the premenstrual stage of a menstrual cycle.
Individuals with PDD may experience extreme mood swings, hopelessness, anger, anxiety, or tension. Once the individual begins their menstruation, the symptoms usually cease.
Common Symptoms of Mood Disorders
Below are some of the common signs that may be experienced by someone who is experiencing a depressive mood:
- Loss of interest in activities that were once enjoyed
- An increase or decrease in appetite
- Difficulty sleeping or sleeping more than usual
- Being easily upset or crying a lot
- Feeling hopeless and worthless
- Physical symptoms such as headaches or stomach aches
- Withdrawing from social events, friends, or family
- Suicidal ideation
Below are some of the common symptoms of manic or hypomanic episodes:
- Feeling extremely energized or elated
- Rapid speech and movement
- Agitation, restlessness, or irritability
- Risk-taking behaviors
- Trying to take on many activities at once
- Racing thoughts
- Grandiosity
Unhelpful Thinking Styles
Depressed moods are often fueled by automatic, negative thought patterns known as unhelpful thinking styles. These habits can go unnoticed, yet they intensify emotional distress. Common examples include:
- Mental filter: Focusing only on the negative part of a situation while ignoring positives.
- Catastrophizing: Blowing events out of proportion and expecting the worst.
- Black and white thinking: Seeing things as all good or all bad, with no middle ground.
- Overgeneralization: Assuming one bad event means “it always happens” or “everyone does this.”
- Jumping to conclusions: Assuming you know what others think (mind reading) or predicting the future negatively.
- Personalization: Blaming yourself for things outside your control.
- Shoulding and musting: Pressuring yourself with rigid “I should” or “I must” statements.
- Labeling: Defining yourself or others with global, negative labels (e.g., “I’m stupid”).
- Emotional reasoning: Believing feelings are facts (“I feel anxious, so something bad will happen”).
- Magnification/minimization: Exaggerating others’ strengths while dismissing your own.
Recognizing these patterns is the first step toward challenging and changing them.
How Are Mood Disorders Diagnosed?
According to DSM‑5 criteria, a major depressive episode — and a diagnosis of Major Depressive Disorder (MDD) — requires at least five symptoms, including either:
- Depressed mood most of the day, or
- Loss of interest or pleasure in usual activities
These symptoms must persist for at least two weeks and cause clinically significant impairment in social, work, or other key areas of life.
Clinicians must also rule out triggers like substance use or medical conditions. The absence of any history of manic or hypomanic episodes is essential to distinguish MDD from bipolar disorders.
Everyday Sadness vs. Clinical Depression
While it’s normal to feel sad due to life circumstances, sadness typically passes and doesn’t disrupt functioning. In contrast, clinical depression:
- Persists day after day for over two weeks,
- Involves symptoms beyond sadness (like concentration impairment, appetite or sleep changes),
- Substantially affects daily life—work, relationships, and self-care.
Adjustment disorder with depressed mood (sometimes called situational depression) may resolve once a stressor passes—whereas MDD is more persistent and requires professional assessment.
Causes and Risk Factors
While there is no known direct cause for someone to develop a mood disorder, there are some possible contributing factors that may play a part.
Often, the cause of mood disorders is thought to be a combination of biological, genetic, psychological, and environmental factors.
Genetic and Biological Factors
Mood disorders tend to run in families, suggesting a genetic component. For example, having a close relative with a mood disorder increases the likelihood of developing one yourself.
Neurotransmitters such as norepinephrine and serotonin appear to play a key role: depressed individuals often show abnormally low levels, while manic episodes are linked to elevated norepinephrine.
Medications that adjust these neurotransmitters can reduce symptoms, further supporting their role (Price & Drevets, 2010; Victor et al., 2010).
Structural differences in the amygdala and prefrontal cortex have also been observed, with abnormal responses to emotional cues in those with depression and bipolar disorder (Murray et al., 2010).
Environmental and Social Factors
Environmental stressors, such as social isolation, substance misuse, or ongoing life pressures, can increase risk.
In recent years, researchers have noted that heavy technology and social media use is linked with higher rates of depression in adolescents, with heavy users nearly twice as likely to report low well-being (Twenge, 2020).
Hormonal Factors
Hormonal fluctuations influence mood for some individuals. Disorders like premenstrual dysphoric disorder (PMDD) and postpartum depression highlight the role of reproductive hormones, particularly estrogen and progesterone, in mood regulation.
Gender and Age Differences
Women are diagnosed with depression almost twice as often as men, which may reflect both biological differences (hormones, reproductive events) and social factors such as willingness to seek help.
Adolescents and young adults show the highest risk, with depression rates rising significantly in U.S. teens between 2011–2018 (Twenge, 2020).
Older adults can also be affected, though symptoms are sometimes mistaken for cognitive decline.
Impact of Mood Disorders on Daily Life
Work & School Functioning
Mood disorders can significantly impair concentration, attendance, and performance. Students experiencing impaired mental health are more likely to underperform academically—leading to poor grades or dropping out entirely (Chu et al., 2022).
In the workplace, depression may result in more days absent and reduced productivity, often resulting in job loss or financial strain.
One person shared:
“Too many jobs lost, lots of financial struggles … due to depression/attendance issues.”
Relationships
Emotional lows, strain, and withdrawal often affect personal relationships. Such dynamics can lead to misunderstandings, isolation, and emotional exhaustion—for both those with mood disorders and their loved ones.
A person living with bipolar disorder reflected:
“I just wanna have a normal stable life the past 4 years have been so incredibly exhausting with all my mood issues.”
Physical Health Links
Mood disorders often affect sleep and appetite, causing both insomnia or hypersomnia, and weight changes.
Physical health is also at risk: people with long-term mental health conditions are more likely to develop heart disease, fatigue, headaches, or digestive issues.
Wearable-device research reinforces this link: poor sleep quality measured by wristband trackers correlates with increased depressive symptoms (Zhang et al., 2020).
Treatment Options for Mood Disorders
Medication
Healthcare providers may recommend medication as part of treatment:
- Antidepressants are commonly prescribed for depressive disorders and work by affecting serotonin or norepinephrine.
- Mood stabilizers such as lithium are often used for bipolar disorder to help regulate mood swings.
- Antipsychotic medications can also be prescribed in certain cases, such as severe mania or treatment-resistant depression.
Psychotherapy
Psychological therapies are frequently used alongside medication. Cognitive behavioral therapy (CBT), for example, has been shown in research to help people identify and challenge unhelpful thought patterns.
For some individuals with mild to moderate symptoms, therapy alone may be effective.
Brain Stimulation Therapies
In treatment-resistant cases, approaches such as electroconvulsive therapy (ECT) or repetitive transcranial magnetic stimulation (rTMS) may be considered by specialists.
These are typically offered when other interventions have not been effective.
Light Therapy
For seasonal affective disorder (SAD), exposure to a light box has been found to reduce depressive symptoms. This is usually recommended as a supplement to other approaches.
Lifestyle and Holistic Approaches
Research suggests that lifestyle factors—such as consistent sleep, exercise, a balanced diet, and stress management practices (e.g., yoga, meditation, or mindfulness)—may help reduce symptoms or support recovery.
Peer support groups can also provide a sense of connection. These are considered complementary strategies, not substitutes for professional care.
Coping and Support
When to Seek Professional Help
Professional help may be appropriate when symptoms:
- Last longer than two weeks,
- Interfere with work, school, or relationships,
- Include suicidal thoughts, or
- Lead to reliance on alcohol or drugs.
Keeping a mood diary can help individuals recognize patterns and share useful information with a clinician.
Supporting a Loved One
Friends and family members can play an important role. Support may include:
- Listening without judgment,
- Encouraging professional evaluation,
- Learning about the condition, and
- Providing practical help (such as attending appointments together).
It’s also important that caregivers look after their own wellbeing, as supporting someone with a mood disorder can be emotionally demanding.
“I didn’t realize how much my depression was affecting work until my partner gently pointed it out. Having someone notice and encourage me to get help made all the difference.”
Do you need mental health help?
USA
Contact the National Suicide Prevention Lifeline for support and assistance from a trained counselor. If you or a loved one are in immediate danger: https://suicidepreventionlifeline.org/
1-800-273-8255
UK
Contact the Samaritans for support and assistance from a trained counselor: https://www.samaritans.org/; email jo@samaritans.org .
Available 24 hours a day, 365 days a year (this number is FREE to call):
116-123
Rethink Mental Illness: rethink.org
0300 5000 927
Related Articles
Self Help Resources for Bipolar Disorder or Manic Depression
National Institute of Mental Health. Bipolar disorder. Updated January 2020.
References
Chu, T., Liu, X., Takayanagi, S., Matsushita, T., & Kishimoto, H. (2022). Association between mental health and academic performance among university undergraduates: The interacting role of lifestyle behaviors. International Journal of Methods in Psychiatric Research, 32(1), e1938. https://doi.org/10.1002/mpr.1938
Murray, E. A., Wise, S. P., & Drevets, W. C. (2011). Localization of dysfunction in major depressive disorder: prefrontal cortex and amygdala. Biological psychiatry, 69(12), e43-e54.
Nathan, P., Rees, C., Lim, L., & Correia, H. (2003). Back from the Bluez. Perth, Western Australia: Centre for Clinical Interventions
Price, J. L., & Drevets, W. C. (2010). Neurocircuitry of mood disorders. Neuropsychopharmacology, 35(1), 192-216.
Price, J. L., & Drevets, W. C. (2012). Neural circuits underlying the pathophysiology of mood disorders. Trends in cognitive sciences, 16(1), 61-71.
Truschel J. (2020, September 29). Bipolar Definition and DSM-5 Diagnostic Criteria. PSYCOM. https://www.psycom.net/bipolar-definition-dsm-5/
Twenge, J. M. (2020). Why increases in adolescent depression may be linked to the technological environment. Current opinion in psychology, 32, 89-94.
Victor, T. A., Furey, M. L., Fromm, S. J., Öhman, A., & Drevets, W. C. (2010). Relationship of emotional processing to masked faces in the amygdala to mood state and treatment in major depressive disorder. Archives of General Psychiatry, 67(11), 1128.
Zhang, Y., Folarin, A. A., Sun, S., Cummins, N., Ranjan, R. B., Rashid, Z., Conde, P., Stewart, C., Laiou, P., Matcham, F., White, K., Lamers, F., Siddi, S., Simblett, S., Rintala, A., Wykes, T., Haro, J. M., Pennix, B. W., Narayan, V. A., . . . Dobson, R. J. (2020). The Relationship between Major Depression Symptom Severity and Sleep Collected Using a Wristband Wearable Device: Multi-centre Longitudinal Observational Study. ArXiv. https://doi.org/10.2196/24604
