Thought blocking occurs when someone is talking and suddenly stops for no clear reason. Losing a train of thought occasionally is common and not usually a cause for concern.

However, it can also be a symptom of a mental health condition such as psychosis. This condition can cause disorganized speech and thinking, as well as hallucinations and delusions, in some cases.

Keep reading to learn more about thought blocking, including some conditions and other factors that may cause it. This article also discusses when to contact a doctor.

Person talking on phone and experiencing thought blocking.Share on Pinterest
fizkes/Getty Images

Thought blocking occurs when someone suddenly stops talking in the middle of doing so. It may also cause someone to stop thinking in the middle of a thought.

According to its loosest definition, thought blocking can technically happen to anyone at any time. It is not uncommon for someone to temporarily forget what they were about to say or to get distracted.

People can also become so consumed by trying to recall a specific detail or memory during a story or train of thought that they may stop talking or shift their attention.

For some people, thought blocking feels as if a thought has permanently left their brain. In these cases, the person may truly be unable to remember their intended thoughts, their words, or the reason they stopped talking.

Everyone forgets what they were about to say or loses their train of thought from time to time. For example, this can be due to:

  • stress
  • exhaustion
  • drowsiness
  • lack of concentration or focus
  • multitasking, such as driving, cleaning, or playing games while talking to someone

However, thought blocking can also occur due to thought disorders or psychosis.


Psychosis occurs when someone interprets and perceives reality very differently from the people around them. It may cause hallucinations (seeing things that are not there), delusions (unrealistic or extreme ideas), and disorganized speech and thinking, such as thought blocking.

Typically, psychosis is known as an “experience” or a symptom of a medical health condition, rather than a specific condition in itself. Psychosis can vary greatly in terms of what a person experiences, and no two people’s experience of it is the same.

In the United States alone, around 100,000 young people experience psychosis every year, and up to 3 in 100 people will experience it in their lifetime.

Learn more about psychosis here.


One of the most common mental health conditions associated with psychosis and thought blocking is schizophrenia.

Schizophrenia is a chronic neurodevelopmental condition that impacts how someone feels, thinks, talks, and acts. It is a fairly uncommon condition, affecting an estimated 0.25% to 0.64% of U.S. adults and around 0.33% to 0.75% of people worldwide.

Learn more about schizophrenia here.

Other conditions

Bipolar disorder can also cause psychosis, though it seems to disrupt mood more than thought.

Thought blocking may also present with other mental health conditions associated with types of psychosis, including:

Other conditions and factors that can cause or increase the risk of psychosis or mental health conditions may also cause thought blocking.

Intense emotion or physical events may also cause someone to consciously or unconsciously “block” out or avoid certain memories, feelings, thoughts, or emotions.

This may cause someone to suddenly stop speaking when they think about or have to talk about something that is tied to these traumatic thoughts, feelings, memories, or emotions.

Other causes and risk factors for thought blocking include:

  • trauma, such as abuse or intense loss
  • physical injury or illness, such as very high fever, poisoning, head injuries, or stroke
  • extreme anxiety
  • drinking alcohol
  • smoking tobacco
  • taking recreational or illegal drugs, such as cannabis, LSD, crack cocaine, heroin, or ecstasy
  • taking certain prescribed medications, such as antidepressants, corticosteroids, some heart medications, and some Parkinson’s medications
  • tapering or stopping antipsychotic medications or mood-stabilizing medications
  • rarely, taking some over-the-counter medications, such as nonsteroidal anti-inflammatory drugs, antihistamines, or cold or flu medications

The best way to treat and manage psychosis depends largely on the cause.

People with schizophrenia often need to take antipsychotic medications that try to counter the chemical imbalance in their brain. They may also benefit from psychosocial services that help them and their family learn how to cope with their condition.

Some examples of these services include:

  • psychotherapy, often cognitive behavioral therapy
  • rehabilitation
  • family education
  • peer counseling or group therapy
  • substance misuse treatment
  • illness management skill classes or groups

People with other mental health conditions that cause psychosis and thought blocking may also benefit from antipsychotics or the following:

  • mood stabilizers
  • antidepressants or antianxiety medications
  • psychotherapy
  • substance misuse counseling or harm-reducing medications
  • Parkinson’s medications
  • autoimmune therapies
  • surgery
  • medication changes
  • lifestyle changes, such as getting proper rest, eating a healthy diet, and avoiding drugs, alcohol, and smoking
  • neurofeedback
  • transcranial magnetic stimulation
  • electrostimulation

Anyone who thinks that they may be experiencing thought blocking, other thought disorders, or psychosis should also talk with a doctor as soon as possible.

People experiencing psychosis may believe that:

  • other people are conspiring against them, talking about them, spying on or tracking them, or acting against them when they are not
  • they have superpowers, are gifted, or are immortal
  • they are an extremely important person, such as the president, when they are not
  • their bodies are distorted in some way
  • their minds are being controlled by outside forces that mean them harm
  • others can read their minds or hear their thoughts
  • they have an intense relationship with God or have a religious destiny or calling
  • people in the media or celebrities are talking directly to them or trying to communicate with them when they are not

Someone with psychosis may also:

  • see, feel, taste, or hear things that are not there
  • repeat certain unusual movements over and over
  • be unable to move or talk
  • have difficulty processing and using information
  • have difficulty making decisions and staying focused
  • suddenly stop taking care of themselves and their hygiene
  • have disorganized thinking or speech
  • accidentally make up fake words (neologisms)
  • keep returning to the same topic or subject, no matter the conversation
  • go far off-topic when talking before returning to their original topic (or not returning to it at all)
  • make no sense when speaking or be unable to follow a train of thought
  • act erratically or overact excessively
  • have suicidal thoughts or behaviors

If a person is experiencing any of these symptoms, they need professional help.

Suicide prevention

If you know someone at immediate risk of self-harm, suicide, or hurting another person:

  • Ask the tough question: “Are you considering suicide?”
  • Listen to the person without judgment.
  • Call 911 or the local emergency number, or text TALK to 741741 to communicate with a trained crisis counselor.
  • Stay with the person until professional help arrives.
  • Try to remove any weapons, medications, or other potentially harmful objects.

If you or someone you know is having thoughts of suicide, a prevention hotline can help. The 988 Suicide and Crisis Lifeline is available 24 hours a day at 988. During a crisis, people who are hard of hearing can use their preferred relay service or dial 711 then 988.

Find more links and local resources.

Was this helpful?

Thought blocking occurs when someone loses a train of thought for no apparent reason, which may cause them to suddenly stop speaking.

Thought blocking is not usually a cause for concern. It can happen to anyone at any time due to factors such as tiredness or stress.

However, it can also be a symptom of a more serious mental health condition, such as schizophrenia.

Treatment for thought blocking focuses on treating the underlying cause. For example, if it occurs due to a mental health condition, treatment could mean seeking therapy or taking medication.

If a person is concerned that they or someone they know might be experiencing psychosis, they should contact a doctor.