In 2016, as the actress and singer Selena Gomez embarked on her world tour to promote her album, Revival, she struggled with depression and anxiety triggered by her ongoing battle with lupus , and ultimately had to cancel the tour after 55 performances.

Her mental health woes didn’t end there. In 2018 she had an episode of psychosis, a condition in which someone loses contact with reality, she’s now revealed in her new Apple TV+ documentary, Selena Gomez: My Mind and Me.

The documentary is based on video taken over six years and takes a close, often raw, look at high and low moments for Gomez, now 30, during that time. Gomez says her key goal in making the documentary was to make it more common for people to talk about mental health struggles.

Gomez did eventually recover from it, according to the documentary. Afterward she was diagnosed with bipolar disorder — which her doctors say is what triggered the psychosis — and began treatment for it, including medication.

Here, experts explain what psychosis is, potential signs and symptoms, and how it’s diagnosed and treated.

What Is Psychosis?

Psychosis is a combination of symptoms resulting in an impaired relationship with reality. That means that you've lost your ability to distinguish between what’s real and what’s not real, says Po Wang, MD, a clinical professor of psychiatry and behavioral sciences at Stanford University in California, who specializes in treating bipolar disorder.

However, doctors may not necessarily use the term “psychosis” when talking about the condition with a patient. “Often, psychiatrists will use the term ‘psychosis’ or ‘psychotic episode’ to talk among themselves about a patient,” says Dr. Wang. But when speaking to a patient, they may be more likely to refer to the episode as an unusual experience or thinking, says Wang.

The reason: Terms like psychosis often come with stigma. “Patients may hear it as a failing rather than as part of an illness. It can be a lot to take in,” says Wang.

Wang applauds Gomez for speaking out about her experience. “Stigma is such a problem that it often prevents people from seeking help,” he says.

Around 70 percent of people worldwide with a mental health condition don’t get treatment for reasons including stigma, according to research published in the American Journal of Public Health.

What Does Psychosis Do to a Person?

Gomez remembers very little about her episode, other than finding herself in a mental health treatment facility, she said in the documentary.

“If anybody saw what I saw in the state that [Gomez] was in at the mental hospital, they wouldn’t have recognized her at all,” said Gomez’s friend Raquelle, in the documentary. “And I was devastated because psychosis can last from days to weeks to months to years to life.”

Psychosis symptoms can vary significantly from person to person, says Holly Swartz, MD , a professor of psychiatry and the medical director of the Depression and Manic Depression Program at the University of Pittsburgh.

Like in Gomez’s case, psychosis can cause someone to have hallucinations — meaning they hear or see things that aren’t there, according to the National Institute of Mental Health (NIMH). “I just remember it being very chaotic, and [Gomez] was hearing all of these voices,” said Gomez’s friend Raquelle, in the documentary. “They just kept getting louder and louder and louder.”

A person with psychosis may also experience delusions, or false beliefs, NIMH experts say. For instance, says Dr. Swartz, they may believe without evidence that someone is out to harm them, leading them to feel very fearful for reasons that aren't grounded in reality.

People can also have what are called “ideas of reference,” says Swartz, which means they perceive meaning where there is none. “So, for instance they hear a song on their playlist and believe that it has very specific messages to them, or about them that go beyond just resonating meaningfully with a song, or with a work of art,” says Swartz.

Sometimes people have experiences that we call “thought insertion” or “broadcasting,” says Swartz, which means you believe someone else is putting thoughts into your brain that aren’t your own, that people can read your thoughts, that you're somehow communicating your thoughts to other people, or that there are complicated plots being developed.

When someone is experiencing psychosis, says Swartz, they often appear to be responding to internal stimuli, or something happening internally rather than in the world around them. For instance, instead of talking to the person next to them, they seem to be paying attention to conversations with people or ideas in their head that are divorced from the world around them.

Other possible signs of psychosis, NIMH experts say, are:

Difficulty thinking or concentrating that represents a change in the person’s previous behavior
Feeling suspicious, paranoid, or uneasy around others
Sudden decline in job or school performance
Spending more time alone than usual
Unusual and intense new ideas or feelings, or conversely, no feelings at all
Lack of self-care or personal hygiene
Having a hard time separating reality from fantasy
Difficulty communicating or confused speech

What Are the Triggers of Psychosis?

Psychosis symptoms can vary greatly from person to person, says Swartz, mainly because there are many different illnesses or problems that could cause them. That can include the use of substances such as hallucinogens, cocaine, and marijuana, as well as disorders such as schizophrenia and bipolar disorder, says Swartz.

Other medical conditions, such as stroke or multiple sclerosis, can also cause psychosis in some patients, adds Wang. Medical issues including low levels of sodium in the body or an electrolyte imbalance could also be culprits, says Swartz.

What Does Psychosis Have to Do With Bipolar Disorder?

Like in Gomez’s case, psychosis can be a symptom of bipolar disorder, a mental health condition that causes mood episodes, or extreme shifts in mood that last weeks at a time or longer. Mood episodes can take the form of mania (feeling extremely elated, energetic, or irritable), hypomania (a less severe version of mania), or depression (feeling deeply sad and hopeless).

In bipolar disorder, manic episodes often alternate with episodes of depression, and they can last weeks or months separated by periods of neutral moods, when a person isn’t experiencing any symptoms, according to Wang.

Psychosis can happen in either a manic or depressive episode. However, some people with bipolar disorder never experience an episode of psychosis, adds Wang.

A manic episode lasts at least one week, says Swartz, and symptoms may include:

Elevated or irritable mood
Increased energy
Grandiosity, or an exaggerated sense of self-worth
Racing thoughts
Decreased need for sleep
Engaging in dangerous or impulsive activities, such as speeding while driving, overspending, or sexual indiscretions

A depressive episode lasts at least two weeks, say Mayo Clinic experts, and can include symptoms such as:

Feeling sad, empty, worthless, or tearful
Loss of interest or pleasure in activities once enjoyed
Appetite changes that lead to weight loss or gain
Not sleeping enough or oversleeping
Restlessness
Slowed behavior
Fatigue or lack of energy
Difficulty thinking, concentrating, or making decisions
Suicidal thoughts or behaviors

How Is Psychosis Treated?

“I can’t emphasize enough that what the treatment is will depend on what’s driving the episode,” says Swartz. So, for example, if tests determine a low sodium level is causing psychosis, then restoring the person’s sodium levels via supplementation could end the episode.

When someone comes to the doctor with a first episode of psychosis, the doctor will take a thorough medical history and run tests to see if there is a reversible medical cause for their symptoms. If someone with psychosis is brought to the emergency room, the first line of treatment will be antipsychotic medications. “Treatment can change over time, especially for bipolar disorders where other medications may be more beneficial,” says Swartz.

In severe cases, people with psychosis need to be hospitalized.

For bipolar disorder, like in Gomez’s case, the mainstay of treatment is mood-stabilizing medication, which is very effective for managing symptoms, says Wang. “Once we get patients to a stable baseline, we can see what else will be effective for that person,” adds Swartz.

Evidence-based forms of psychotherapy for bipolar disorder can include cognitive behavioral therapy , family-based psychotherapy, or other forms of therapy, says Swartz. These therapies have been shown to reduce symptoms and reduce risks of new episodes of both depression and mania.