What part of the brain does psychosis affect

Two brain chemicals may interact to contribute to the development of psychotic disorders such as schizophrenia, according to a new study.

The results suggest abnormal levels of the neurotransmitter glutamate may lead to changes in the levels of another neurotransmitter, dopamine, causing the transition into psychosis. Though both chemicals have been studied before, the interaction between them has been brought to light by the new study, the researchers say.

Targeting this interaction may be a way to treat these mental disorders and possibly prevent them from occurring, the researchers say.

"If we could prevent this kind of abnormal glutamate-dopamine interaction early enough in the illness, it might prevent people from actually going on to get full blown psychosis," said study researcher James Stone, of King's College London in the United Kingdom.

Dopamine and glutamate

Scientists have long known that dopamine is involved in the development of schizophrenia and other psychotic disorders. People with schizophrenia have an overactive dopamine system, releasing more dopamine than healthily people. Currently, the drugs used to treat schizophrenia aim to regulate dopamine levels in the brain.

But scientists say dopamine doesn't tell the whole story. Some people with schizophrenia don't respond to dopamine-regulating drugs, Stone said. And most of the genes that have been linked to schizophrenia are involved in the production or regulation of glutamate, not dopamine. Drugs such as PCP that act on the glutamate system produce symptoms similar to those seen in schizophrenia.

Previous studies have shown schizophrenia patients have changes in their glutamate systems, but no one had looked at how glutamate and dopamine interact in the same person.

Stone and his colleagues examined images of the brains of 16 individuals who had some psychotic symptoms, but whose symptoms were not intense enough for them to be diagnosed with schizophrenia. Instead, they have an illness known as "at-risk mental state for psychosis," and are known to be at risk for developing schizophrenia later on. These brain images were compared to those of 12 healthily volunteers.

In the "at risk" patients, low glutamate levels in one part of the brain, called the hippocampus, were associated with increased dopamine activity in another brain area called the striatum.

This relationship was not seen in the healthy volunteers.

"This suggests that these people have something abnormal in terms of their glutamate-dopamine interactions," Stone told MyHealthNewsDaily.

Schizophrenia drugs

The results provide more evidence that glutamate is indeed involved in the development of schizophrenia, Stone said.

And the study supports the idea that drugs for schizophrenia that target glutamate as well dopamine should be developed.

It's possible that future research may lead to a way to use these chemical abnormalities, in addition to genetic testing, as risk markers for schizophrenia, Stone said.

The study is published in the October issue of the journal Biological Psychiatry. 

Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.

What Is Psychosis?

Psychosis is a condition that affects the way your brain processes information. It causes you to lose touch with reality. You might see, hear, or believe things that aren’t real. Psychosis is a symptom, not an illness. It can be triggered by a mental illness, a physical injury or illness, substance abuse, or extreme stress or trauma.

Psychotic disorders, like schizophrenia, involve psychosis that usually affects you for the first time in the late teen years or early adulthood. Young people are especially likely to get it, but doctors don’t know why. Even before what doctors call the first episode of psychosis (FEP), you may show slight changes in the way you act or think. This is called the prodromal period and could last days, weeks, months, or even years.

Sometimes you can lose touch with reality even when you don’t have a primary psychotic illness such as schizophrenia or bipolar disorder. When this happens, it's called secondary psychosis.

These episodes stem from something else, like drug use or a medical condition. Whatever the reason, they tend to disappear in a short time, and they often stay away if you treat the condition that caused them.

Symptoms of Psychosis

Psychosis doesn’t suddenly start. It usually follows this pattern:

• Warning signs before psychosis: It starts with gradual changes in the way you think about and understand the world. You or your family members may notice:
  • A drop in grades or job performance
  • Trouble thinking clearly or concentrating
  • Suspiciousness or unease around others
  • Lack of self-care or hygiene
  • Spending more time alone than usual
  • Stronger emotions than situations call for
  • No emotions at all
• Signs of early psychosis: You may:
  • Hear, see, or taste things others don’t
  • Hang on to unusual beliefs or thoughts, no matter what others say
  • Pull away from family and friends
  • Stop taking care of yourself
  • Not be able to think clearly or pay attention
• Symptoms of a psychotic episode: Usually you’ll notice all of the above plus:
  • Hallucinations:
    • Auditory hallucinations: Hearing voices when no one is around
    • Tactile hallucinations: Strange sensations or feelings you can’t explain
    • Visual hallucinations: You see people or things that aren’t there, or you think the shape of things looks wrong
  • Delusions: Beliefs that aren’t in line with your culture and that don’t make sense to others, like:
    • Outside forces are in control of your feelings and actions.
    • Small events or comments have huge meaning.
    • You have special powers, are on a special mission, or actually are a god.

Causes of Psychosis

Doctors don’t know exactly what causes psychosis, but some known risk factors include:

• Genetics: You can have the genes for it, but that doesn’t always mean you’ll get psychosis.
• Drugs: Triggers include some prescription medications and abuse of alcohol or drugs like marijuana, LSD, and amphetamines.
• Trauma: The death of a loved one, a sexual assault, or war can lead to psychosis. The type of trauma and the age you were when it happened also play a role.
• Injuries and illnesses: Traumatic brain injuries, brain tumors, strokes, Parkinson’s disease, Alzheimer’s disease, dementia, and HIV can all bring on psychosis.

Psychosis can also be a symptom of a mental illness, like schizophrenia or bipolar disorder.

Drugs  

Both drugs that depress the nervous system, like cannabis (marijuana), and stimulant drugs, like cocaine and amphetamines, can affect your brain activity in dramatic ways, so that what seems real to you doesn't match with the world.

Most of the time, this goes away when you stop use of the drug. But there’s a strong link between all these drugs and primary psychosis. More than 25% of those who are diagnosed with amphetamine-induced psychosis later have psychotic disorders. Cannabis is involved in roughly half of all cases.

Studies suggest that these drugs may not so much cause psychosis as uncover the condition when it’s already present among people with psychiatric conditions, such as schizophrenic disorders or a family history of psychosis.

Drugs used to treat mental illness can lead to problems as well. Although it’s rare, if you've been taking an antipsychotic (such as chlorpromazine, fluphenazine, haloperidol, perphenazine, and others) for many months or years, you could develop a movement disorder call tardive dyskinesia because of the long-term effects of the medication on your brain.

And if you stop taking an antipsychotic medicine, you may get supersensitivity psychosis. Doctors think it happens because ongoing use of this type of drug changes how your brain responds to the chemical dopamine. Some antipsychotic medications, like aripiprazole (Abilify), carry an increased risk of psychosis.

Most drug-triggered symptoms will clear up after the drug leaves your system. But psychosis from cocaine, PCP (aka angel dust), and amphetamines could last for weeks. While you wait for the episode to pass, your doctor can ease the symptoms with an anti-anxiety drug such as lorazepam (Ativan) or maybe an antipsychotic.

Medical conditions

Postictal psychosis (PIP) happens in some people with epilepsy who've had a number of seizures in a row. It's more likely when you've had a seizure disorder for a long time or you've had mental illness in the past.

Antipsychotic drugs like olanzapine and risperidone can stop symptoms and may help prevent future episodes.

Myxedematous psychosis may happen when your thyroid gland doesn't work well, known as hypothyroidism. Because of the way thyroid hormone affects your brain, you may have hallucinations, delusions, and changes to your sense of taste or smell if there's not enough in your body. Your doctor can test your level of thyroid-stimulating hormone (TSH) to confirm myxedema psychosis and rule out other conditions like schizophrenia.

Taking thyroid hormone can help balance your gland's activity and end the psychosis.

Female hormone shifts

Although it's extremely rare, some women have menstrual psychosis. Out-of-balance hormones at different points in your cycle can affect thinking and moods. This type of psychosis can appear at the beginning, around ovulation, or during the few days before your period starts.

Menstrual psychosis can show up quickly and can disappear just as fast. During the episodes, you may be confused about what's real, hallucinate, and believe things that aren't true.

Cognitive behavioral therapy (CBT) and antipsychotic drugs can help ward off your symptoms, even with hormone levels that are hard to predict.

Diagnosis

You can see a psychologist, psychiatrist, or a social worker. They’ll find out what might have caused your symptoms and look for related conditions. Doctors diagnose mental illnesses after ruling out other things that could be causing psychotic symptoms.

Medical Treatment for Psychosis

It’s important to get treated early, after the first episode of psychosis. That will help keep the symptoms from affecting your relationships, work, or school. It may also help you avoid more problems down the road.

Your doctor may recommend coordinated specialty care (CSC). This is a team approach to treating schizophrenia when the first symptoms appear. It combines medicine and therapy with social services and work and education support. The family is involved as much as possible.

What your doctor recommends will depend on the cause of your psychosis.

Your doctor will prescribe antipsychotic drugs -- in pills, liquids, or shots -- to ease your symptoms. They’ll also suggest you avoid using drugs and alcohol.

You might need to get treated in a hospital if you’re at risk of harming yourself or others, or if you can't control your behavior or do your daily activities. The doctor will check your symptoms, look for causes, and suggest the best treatment for you.

Some clinics and programs offer help just for young people.

Psychotherapy

Counseling, along with medicines, can also help manage psychosis.

• Cognitive behavioral therapy(CBT) can help you recognize when you have psychotic episodes. It also helps you figure out whether what you see and hear is real or imagined. This kind of therapy also stresses the importance of antipsychotic medications and sticking with your treatment.
• Supportive psychotherapy helps you learn to live with and manage psychosis. It also teaches healthy ways of thinking.
• Cognitive enhancement therapy (CET) uses computer exercises and group work to help you think and understand better.
• Family psychoeducation and support involves your loved ones. It helps you bond and improves the way you solve problems together.
• Coordinated specialty care (CSC) creates a team approach in treating psychosis when it’s first diagnosed. CSC combines medication and psychotherapy with social services and work and education support.