Bipolar disorder is a mental health condition that causes sudden shifts in mood.

According to the National Institute of Mental Health, an estimated 4.4% of adults in the United States will experience bipolar disorder at some point during their lives. If untreated, this condition can have negative impacts on daily tasks and decision-making.

A 2009 study on the long-term effects of bipolar disorder showed that it can cause structural changes to the brain, especially in some lower parts of the frontal lobe. These changes were visible in older participants after an MRI — an imaging test that shows tissues and other structures on the inside of your body.

In this article, we’ll explore the types of brain changes associated with bipolar disorder and why timely treatment is important for the best outcomes.

Theoretical physicist Michio Kaku perhaps said it best when he referred to the human brain as “the most complex object in the known universe.”

The Department of Health and Human Services hosts an overview of the nervous system that states that there are around 100 billion neurons (nerve cells) inside the human brain. Neurons transmit electrical and chemical signals all over the body, controlling every aspect of our bodily functions.

Anatomically, your brain is composed of three primary structures:

  • the cerebrum
  • the cerebellum
  • the brainstem

Within the cerebrum, you can find four lobes:

  • The frontal lobe is responsible for memory involved in planning, speech and language, decision-making, and some motor functions.
  • The parietal lobe handles a lot of sensory input (touch, pain, temperature), and is also involved in sensorimotor planning (determining movements), learning, language, and spatial recognition.
  • The temporal lobe is responsible for sound recognition, semantic memory (remembering common knowledge), and visual perceptions, including faces and familiar objects.
  • The occipital lobe is in charge of processing and interpreting visual information, which is then sent out to other parts of the brain for analysis.

Each of these lobes is a different size, and many have multiple parts responsible for specific functions.

According to early research on the subject, MRI scans in people with bipolar disorder show changes within the following areas of the brain:

  • Prefrontal cortex. The prefrontal cortex is located at the front of the frontal lobe. Studies suggest that people with bipolar disorder may have decreased gray matter volume in the prefrontal cortex, specifically in the subgenual prefrontal cortex (SGPFC), which appears to regulate mood.
  • Subcortical structures. The subcortical structures are located beneath the cerebral cortex, deep within the brain. Studies have found that in people with bipolar disorder, certain areas in the center of the brain that control emotional, cognitive, and social behavior may be enlarged.
  • Medial temporal structures. The medial temporal lobe includes structures such as the hippocampus and amygdala. Studies have found mixed changes in these structures in people with bipolar disorder, including increased amygdala size, which can have an impact on emotional regulation.

In addition, functional imaging studies, which allow researchers to view how the brain is functioning during episodes, suggest that bipolar disorder can cause functional abnormalities.

For example, studies have shown decreased activity in the prefrontal cortex during both manic and depressive episodes — as well as increased activity in the amygdala and other areas of the anterior limbic network, which are linked to emotional arousal.

However, it’s important to remember none of the data is conclusive yet. Researchers are still seeking to understand what connections may exist between brain structure and function in relation to bipolar disorder.

Although imaging studies show many different areas of the brain that are affected by bipolar disorder, perhaps one of the biggest impacts of bipolar disorder is on the gray matter of the brain. Gray matter is a type of brain tissue that primarily surrounds the outer layer of the brain, creating what is known as the cerebral and cerebellar cortexes.

Gray matter is filled with neurons and is essential to all our functions. Gray matter makes it possible for us to control our physical movements, remember things, and experience emotions.

In a large study from 2017, researchers gathered information about cortical gray matter thickness and surface area from over 6,500 brain scans — including scans from over 1,800 bipolar disorder patients. Results of the study found that, when compared with healthy controls, people with bipolar disorder had decreased gray matter thickness in the frontal, temporal, and parietal lobes.

Since gray matter plays an essential role in everything our bodies do, a decrease in gray matter can lead to long-term health effects. In people with bipolar disorder, receiving timely and effective treatment may help prevent potential damage to gray matter.

There are three characteristic mood episodes associated with bipolar disorder (depression, mania, and hypomania), as well as stable periods called euthymia.

While there are several types of bipolar disorder, the most common are types 1 and 2. Your bipolar type diagnosis will depend on the frequency and severity of your mood episodes, among other factors.

Although the symptoms of bipolar disorder can vary from person to person, they generally include periods of mania (or hypomania) and depression.

Here’s a simple breakdown of which type of bipolar disorder typically includes which features.

disorder type
bipolar I disorder
bipolar II disorder

During a manic episode, you may experience the following symptoms:

  • a high or elevated mood
  • more energy than usual
  • racing thoughts
  • fast speech
  • not sleeping well or at all
  • decreased appetite
  • weight loss
  • engaging in behaviors that may have harmful effects, such as excessive spending or unsafe sex

During a hypomanic episode, which is primarily a symptom of bipolar II disorder, you may notice some of the same symptoms as mania — but hypomania is much less severe and doesn’t cause psychotic features, such as hallucinations or delusions.

During a depressive episode, you may experience the following symptoms:

  • feeling down or hopeless
  • decreased energy
  • difficulty falling or staying asleep, or oversleeping
  • weight or appetite changes
  • trouble concentrating or remembering things
  • lack of motivation, even for daily tasks like showering or eating
  • loss of interest in activities you enjoy
  • thoughts of death or suicide

Help is out there

If you or someone you know is in crisis and considering suicide or self-harm, please seek support:

If you’re calling on behalf of someone else, stay with them until help arrives. You may remove weapons or substances that can cause harm if you can do so safely.

If you are not in the same household, stay on the phone with them until help arrives.

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If you’ve been diagnosed with bipolar disorder, it’s important to work closely with your doctor, psychiatrist, or care team to find the right treatment for you.

Generally, first-line treatment options for bipolar disorder include medication and therapy, often together.


Medication is still considered the gold standard treatment option for bipolar disorder — especially when used in combination with the therapy options outlined in the next section.

Commonly prescribed medication options for bipolar disorder include:

  • Mood stabilizers. Mood stabilizing medications can help reduce the extreme symptoms that accompany manic and depressive episodes in people with bipolar disorder. In addition, long-term mood stabilizers may also help reduce the risk of relapse and may even reduce suicide risk. Lithium is the most prescribed mood-stabilizing medication for bipolar disorder.
  • Anticonvulsants. Anticonvulsant medications are typically used to treat seizures; however, they have been shown to function as mood stabilizers in people with bipolar disorder. Valproic acid and carbamazepine have both been found to treat mania as effectively as lithium, while lamotrigine is most effective for bipolar I disorder.
  • Second-generation antipsychotics (SGAs). SGAs are generally paired with mood stabilizers to treat manic and mixed bipolar disorder episodes. In addition, SGAs can help treat the symptoms of acute mania or depression. Quetiapine and a mixed medication regimen called Symbyax (olanzepine and fluoxetine) are examples of SGAs prescribed for bipolar disorder.
  • Antidepressants. Although antidepressants can be used in some people with bipolar disorder, they should be used with caution, as they can sometimes trigger manic episodes. The National Alliance on Mental Illness (NAMI) recommends strongly weighing the risks and benefits before taking antidepressants for bipolar disorder.

Medication’s effect on gray matter

Interestingly, results from the 2017 study mentioned above suggest that certain medications prescribed for bipolar disorder can have an effect on gray matter thickness. For example, lithium was found to increase gray matter thickness, while anticonvulsants and atypical antipsychotics were associated with reduced gray matter thickness and surface area, respectively.

However, another study on older adults with bipolar disorder found that lithium (and other antipsychotics) may potentially lower cognitive function in older adults with the condition. It’s important to get thorough medication counseling from your doctor. Pay close attention to possible side effects of any medication you take.


Several types of therapy have proven effective treatment options for bipolar disorder, especially when paired with medication.

Therapy can help you learn to better manage the things in your life that can trigger a bipolar disorder episode, such as stress at work, home, or school. Your therapist can provide a safe space to talk about anything that’s troubling you. They can also help you process your emotions.

Common therapy options for bipolar disorder include:

  • Cognitive behavioral therapy (CBT). CBT focuses on the connection between one’s thoughts, feelings, and behaviors. CBT can teach you how to identify the patterns that make your symptoms worse and work through them to alleviate symptoms.
  • Dialectical behavioral therapy (DBT). DBT primarily focuses on the concepts of acceptance and mindfulness. DBT can teach you how to better tolerate your distress, regulate your emotions, and nurture your interpersonal relationships.
  • Family-focused therapy (FFT). FFT focuses on the important role of family members in the management of bipolar disorder. FFT can allow your loved ones to learn more about what bipolar disorder is, including how to recognize the warning signs of an episode and how to better communicate during conflicts.
  • Interpersonal and social rhythm therapy (IPSRT). IPSRT focuses on the importance of regulating one’s routines, sleep-wake cycles, and interpersonal relationships. IPSRT can teach you how to recognize the effects that these routines can have on your mood, as well as how to solve interpersonal conflicts.

Electroconvulsive therapy (ECT)

ECT is a procedure in which electrodes, which are placed on the side or top of the head, are used to transmit electrical currents to the brain and induce a seizure. Anyone receiving ECT is medicated beforehand with sedatives, muscle relaxants, or even general anesthesia.

ECT is considered a safe and effective treatment for bipolar disorder. It is usually prescribed to people with severe mania or depression whose bipolar disorder has not responded to other treatment options.

In one large study, researchers investigated the effectiveness of ECT in 500 patients with bipolar disorder experiencing manic, depressive, mixed, or catatonic episodes. The authors found ECT was effective in improving symptoms in over 68 percent of patients — all of whom had been previously unresponsive to traditional forms of treatment.

Research has shown that bipolar disorder may cause changes to our gray matter, which controls functions related to our movement, emotions, and more. Untreated bipolar disorder may damage gray matter over time, which can potentially cause health complications later in life.

If you’ve been diagnosed with bipolar disorder, it’s important to work closely with a mental health professional to find the right treatment options for your symptoms. Bipolar disorder is a lifelong condition, but it’s very treatable.

With the right treatment and a strong support network, many people can manage bipolar disorder and live a full life. Positive treatment impacts won’t just make a difference in your day-to-day routine, but will likely be beneficial for your brain’s health as well.