Clinical Interventions Diagnostic Criteria

Using Cognitive Behavioural Therapy (CBTp) to Treat Psychosis

This article outlines key cognitive behavioural therapy (CBTp) principles and techniques for psychosis, reviewing diagnostic criteria, symptoms, and evidence-based interventions.

By Mental Health Academy

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This article outlines key cognitive behavioural therapy (CBTp) principles and techniques for psychosis, reviewing diagnostic criteria, symptom profiles, and evidence-based interventions.

Related articles: Understanding Dissociation, Innovative Approaches to Cognitive Behavioural Therapy, Treating Generalised Anxiety with Cognitive Behavioural Therapy.

Related discussion: What’s your approach to working with psychosis?

Related resource: CBT for Psychosis (CBTp): Session Checklist

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Introduction

Cognitive behavioural therapy (CBT) has become a cornerstone of evidence-based practice in mental health care, used to treat a wide range of conditions such as depression, anxiety disorders, eating disorders, and substance use disorders (Beck, 1979; Knapp & Beck, 2008). Over the past few decades, the utilisation of CBT has expanded to address symptoms associated with psychosis, including schizophrenia and schizoaffective disorders (NICE, 2014).

This article introduces key principles and techniques of cognitive behavioural therapy (CBT) for psychosis. We begin with an overview of CBT concepts, then explore psychosis by outlining diagnostic criteria, common symptoms, co-occurring conditions, and patient outcomes. Next, we review the evidence base for CBT in psychosis, highlighting relevant research and outcome statistics. We also present practical interventions and case studies that demonstrate therapy structure and dialogue. Finally, we conclude with clinical considerations and key takeaways.

An introduction to cognitive behavioural therapy (CBT)

Cognitive behavioural therapy is a psychotherapeutic approach that emphasises the relationship between thoughts (cognitions), feelings (emotions), and behaviours (Beck, 1979). The central premise is that maladaptive or distorted thinking patterns significantly contribute to emotional distress and dysfunctional behaviour. By identifying and challenging unhelpful beliefs, patients can adopt healthier thinking styles and coping mechanisms.

CBT is structured, time-limited, and goal-oriented. Sessions often follow an agenda focusing on the patient’s specific problems and targeted interventions. These interventions encourage patients to reflect on their cognitive processes, examine the evidence supporting their thoughts, and consequently adopt more adaptive perspectives (Wright et al., 2017).

Rationale

One of the reasons CBT has gained wide acceptance is its emphasis on empirical validation and measurable outcomes. Developed initially for depression, it rapidly expanded to include techniques applicable to a variety of mental health challenges. The rationale behind CBT is that if we can help patients think differently, this cognitive shift will produce positive changes in their emotions and behaviour (Knapp & Beck, 2008). This interplay between cognition, emotion, and behaviour is essential in conceptualising the patient’s problem and designing interventions aimed at lasting symptom relief.

Techniques

Common CBT techniques include:

  • Thought records: Patients systematically record situations, associated thoughts, feelings, and alternative viewpoints. This allows a structured review of cognitions and challenges cognitive distortions.
  • Behavioural experiments: Patients test the accuracy of their beliefs through planned activities. For instance, a patient who believes they are unable to engage in social interactions may complete a controlled “social experiment” to gather evidence around their fears.
  • Activity scheduling: This is often used for patients who experience low mood or anxiety that leads to avoidance. By scheduling meaningful or pleasurable activities, patients gradually break the cycle of inactivity and negative thinking.
  • Graded exposure: Patients are gradually exposed to anxiety-provoking situations in a controlled manner, helping them learn that their feared outcomes are less likely or more manageable than previously thought (Knapp & Beck, 2008).

Applications in mental health care

CBT has been found effective for numerous mental disorders, including:

  • Depression: Traditional Beckian CBT was first formulated for depression and continues to be a gold-standard intervention (Beck, 1979).
  • Anxiety disorders: CBT is highly efficacious in treating phobias, social anxiety, panic disorder, and generalised anxiety disorder (Butler et al., 2006).
  • Eating disorders: Techniques have been adapted for normalising perceptions of body image, managing dietary restrictions, and addressing self-esteem (Fairburn et al., 2003).
  • Addictive disorders: CBT helps in recognising maladaptive thought processes and developing coping strategies to prevent relapse (Wright et al., 2017).

More recently, increased attention has been given to psychosis, particularly in the context of schizophrenia spectrum disorders. Research evidence has shown that individuals with psychosis can benefit significantly from strategies like cognitive restructuring, reality testing, and techniques aimed at reducing the distress linked to unusual beliefs or hallucinations (Morrison, 2017).

Understanding psychosis

Diagnostic criteria

The term psychosis refers to a cluster of symptoms involving a loss of contact with reality, typically manifesting through hallucinations, delusions, disorganised thinking, or catatonic behaviour. In the Diagnostic and Statistical Manual of Mental Disorders (5th ed., text rev.; APA, 2022)—also referred to as the DSM-5-TR—psychotic disorders such as schizophrenia and schizoaffective disorder are characterised primarily by the presence of these symptoms over specified time frames. Although the DSM-5-TR is a text revision (rather than a new numbered edition) and retains much of the foundational structure from DSM-5 (APA, 2013), it includes updated text and coding clarifications relevant to diagnosis and clinical practice.

For a diagnosis of schizophrenia, the DSM-5-TR requires at least two of the following five symptom categories: delusions, hallucinations, disorganised speech, grossly disorganised or catatonic behaviour, and negative symptoms (e.g., diminished emotional expression)—with at least one of the symptoms being delusions, hallucinations, or disorganised speech (APA, 2022). The symptoms must persist for a significant period, and social or occupational dysfunction is also a key factor. Other psychotic disorders (e.g., brief psychotic disorder, schizophreniform disorder, and schizoaffective disorder) employ similar core symptoms but vary in duration requirements and associated mood components.

Symptomology

Psychosis is commonly conceptualised in terms of positive, negative, and disorganised symptoms:

Positive symptoms

  • Hallucinations: Sensory perceptions in the absence of external stimuli, which may be auditory, visual, tactile, gustatory, or olfactory.
  • Delusions: Firmly held false beliefs not congruent with cultural or subcultural norms, such as persecutory or grandiose delusions.

Negative symptoms

  • Affective Flattening: Reduced emotional expression or reactivity.
  • Alogia: Poverty of speech or content.
  • Avolition: Lack of motivation or inability to initiate and persist in goal-directed behaviours.
  • Social withdrawal: Diminished engagement with others.

Disorganised symptoms

  • Disorganised speech: Examples include frequent derailment or tangential statements that are difficult to follow.
  • Disorganised behaviour: Behaviours that appear bizarre or lack clear purpose, potentially leading to difficulties in performing daily activities.
  • Catatonic behaviour: Marked decrease in response to the environment, which can include stupor, rigidity, posturing, or extreme negativism.

These symptoms often vary in intensity and duration over the course of the illness. Early identification and appropriate intervention can mitigate long-term functional decline.

Co-occurring disorders

Comorbidity is common among individuals experiencing psychosis. The DSM-5-TR (APA, 2022) recognises that co-occurring disorders, such as substance use disorders and mood or anxiety disorders, can complicate diagnosis and treatment. Some notable overlaps include:

  • Substance use disorders: Psychoactive substances (e.g., cannabis, amphetamines) can exacerbate or precipitate psychotic symptoms.
  • Mood disorders: Conditions like major depressive disorder or bipolar disorder with psychotic features can make accurate diagnosis challenging, as the presence of mood symptoms can interact with or mask psychotic symptoms.
  • Anxiety disorders: Chronic anxiety and panic may worsen paranoia or encourage social withdrawal, contributing to a cycle of exacerbated psychotic symptoms.

A comprehensive, multidisciplinary approach—often incorporating medication, psychosocial support, and psychological therapies like cognitive behavioural therapy—tends to be most effective when dealing with individuals facing multiple challenges (NICE, 2014).

Patient outcomes

Outcomes in psychosis vary considerably, influenced by factors such as the duration of untreated psychosis, responsiveness to antipsychotic medication, social support networks, and the presence of comorbid conditions (NICE, 2014). Early intervention initiatives, especially those employing specialised services, can significantly improve long-term prognoses. Despite this, some individuals continue to experience chronic courses of illness with persistent or relapsing symptoms (Morrison, 2017).

Psychosocial interventions, including CBT for psychosis, play a vital role in improving day-to-day functioning, reducing distress, and lowering relapse rates. The DSM-5-TR (APA, 2022) acknowledges the importance of a holistic treatment model—encompassing pharmacotherapy, psychological therapies, and robust community and family support—to optimise both symptom reduction and quality of life.

Using CBT in psychosis: Context and evidence base

Why use CBT (CBTp) for psychosis?

Psychotic symptoms, particularly delusions and hallucinations, often arise from and are maintained by specific patterns of appraisal and interpretation. For example, a person experiencing auditory hallucinations may interpret these voices as evidence of being under surveillance, while another might conclude they are receiving divine messages (Morrison, 2017). CBT helps to:

  • Normalise the experience: By offering alternative explanations for unusual experiences, CBT can reduce the stigma and distress attached to psychotic symptoms.
  • Promote reality testing: Through guided discovery and Socratic questioning, individuals are encouraged to test the validity of their beliefs and consider alternative perspectives.
  • Enhance coping: Strategies such as relaxation techniques, mindfulness, and distraction help to manage distressing hallucinations or anxious states triggered by delusional concerns (Wright et al., 2017).

Evidence base and outcome statistics

Multiple meta-analyses and systematic reviews have demonstrated that CBT can be effective for reducing psychotic symptoms, particularly in combination with antipsychotic medication (NICE, 2014; Wykes et al., 2008). While medication remains a first-line treatment for psychosis, CBT significantly improves coping skills, insight, and treatment adherence.

A landmark meta-analysis by Wykes and colleagues (2008) found that CBT reduced both positive and negative symptoms of psychosis, with moderate effect sizes. Furthermore, CBT has been shown to reduce relapse rates and depression, reduce general psychopathology, and improve overall functioning (Lincoln et al., 2012). Recent studies emphasise the role of CBT in preventing the transition from an at-risk mental state to full-blown psychosis (French & Morrison, 2008). The National Institute for Health and Care Excellence (NICE) guidelines (2014) recommend that CBT should be offered to all individuals experiencing psychosis or at risk of psychosis.

Specific applications of CBT for psychosis

Assessment and formulation

An integral first step in CBT for psychosis is a comprehensive assessment, collecting information about:

  • Symptom profile: Which hallucinations or delusions are present, their frequency, triggers, and meaning to the patient.
  • Current coping strategies: How the person responds to or attempts to manage these symptoms.
  • Social context: Living situation, support network, cultural influences, and occupational status.
  • Comorbidities: Substance use, mood disturbances, or anxiety that might influence treatment.

From this data, clinicians develop a collaborative case formulation, linking the patient’s experiences with potential maintaining factors such as maladaptive beliefs or safety behaviours (Morrison, 2017).

Therapy structure

CBT for psychosis often follows a structured format:

  1. Engagement and rapport building: Due to the nature of psychotic symptoms, establishing trust is paramount. Empathy, genuine respect for the patient’s perspective, and demonstrating real interest in their experiences is key.
  2. Psychoeducation: Patients are provided with information about psychosis, the nature of CBT, and how thoughts influence emotions and behaviours.
  3. Goal setting: Goals may include reducing the distress associated with hallucinations, decreasing conviction in delusional beliefs, or improving overall functioning.
  4. Intervention phase: This is the bulk of therapy, focusing on cognitive restructuring, coping strategies, and behavioural experiments tailored to psychotic symptoms.
  5. Relapse prevention: Therapy concludes by identifying early warning signs of relapse and developing a plan to maintain progress.

Interventions and techniques

CBT for psychosis typically utilises a variety of targeted interventions designed to address both the specific symptoms of psychosis (e.g., hallucinations, delusions) and the overarching cognitive and behavioural processes that maintain these experiences. By integrating strategies such as normalisation, Socratic questioning, and cognitive restructuring within a collaborative framework, therapists help patients develop insight, reduce distress, and acquire more adaptive coping skills.

Below we explore these interventions in more detail, highlighting their relevance and application to common psychotic presentations.

  • Normalisation techniques: One of the most influential strategies in CBT for psychosis involves normalising the experience of psychosis. Patients learn that hallucinations and delusional beliefs can be understood on a continuum of human experiences, reducing shame and stigma.
  • Socratic questioning: Through gentle, inquisitive dialogue, patients evaluate the realism and helpfulness of their beliefs. For instance, a patient who believes the television is transmitting secret messages might be gently guided to consider alternative explanations and the evidence for each possibility.
  • Cognitive restructuring: Similar to traditional CBT, therapists work with the patient to challenge and reframe unhelpful thoughts, eventually adopting more flexible, adaptive interpretations (Wright et al., 2017).
  • Attention switching and mindfulness: These techniques help patients reduce their focus on distressing hallucinations or paranoid thoughts by directing attention towards neutral or positive stimuli.
  • Relapse prevention planning: Therapists collaborate with patients to develop strategies for recognising early warning signs. By rehearsing coping techniques, patients are better equipped to manage symptoms should they return (Morrison, 2017).

Case studies: Practical illustrations of CBT for psychosis

Case studies offer valuable insights into how CBT can be tailored to address the unique challenges of psychosis. The following examples highlight the process of engagement, formulation, and intervention. All names and identifying details have been changed to protect confidentiality.

Case study one: “James”

James, a 28-year-old male, was referred to a community mental health team due to persistent auditory hallucinations. He believed the voices belonged to government agents who criticised his every move. This belief led him to isolate himself and avoid leaving his flat for fear of being monitored.

Assessment and formulation:

  • James reported that the voices were threatening, labelling him as a “traitor”.
  • He believed that by staying indoors, he could remain “invisible” to the agents.
  • This avoidance behaviour, however, reinforced his belief that leaving home was dangerous and hindered any real-life testing of these paranoid thoughts.
  • He also experienced low mood and significant anxiety.

Therapeutic process:

  1. Engagement and rapport: The therapist spent the first few sessions getting to know James, emphasising empathy and respect for his experiences. They discussed James’s interests (music and literature) to build rapport.
  2. Psychoeducation: Together, they explored how stress might exacerbate psychotic symptoms, and how certain triggers (e.g., watching conspiracy-related news) could intensify his paranoid thoughts.
  3. Normalisation: The therapist introduced the concept that hearing voices, although distressing, can be more common than James had believed. They discussed how individuals can experience voices when they are highly stressed or traumatised.
  4. Cognitive restructuring: One key belief James held was, “If I go out, I will be harmed by government agents.” Socratic questioning was used:
    • Therapist: “What makes you think that the government agents are specifically targeting you?”
    • James: “They say I’m a traitor. They talk directly to me.”
    • Therapist: “Do you recall any specific evidence that someone physically tried to harm you when you last stepped outside?”
    • James: “No… but it felt like they were waiting.”
    • Therapist: “Do we have any evidence beyond that feeling? If we tried a small test, like walking to the local shop, how might we assess whether they are actually out there?”
  5. Behavioural experiment: To test the validity of his belief, James and the therapist planned a brief walk to the local corner shop. James reported feeling anxious but completed the experiment. Upon returning, he recognised that he had not been attacked or followed. By repeating these experiments, James started to gather contrary evidence to his paranoid belief.
  6. Attention switching and coping strategies: James learned to shift focus when the voices became critical, turning to an audiobook or calling a trusted friend. Over time, he noticed that the voices lessened in intensity when he was engaged in meaningful activities.

Outcome: After four months of weekly sessions, James demonstrated reduced conviction in his delusion, increased social engagement, and a significant decrease in auditory hallucinations. He continued to experience occasional voices but recognised them as stress-related, rather than government-originated.

Case study two: “Jasmine”

Jasmine, a 35-year-old woman, experienced fixed beliefs that she was responsible for causing the COVID-19 pandemic through her “negative energy.” She often reported hearing a disembodied voice confirming her “guilt.” Jasmine felt immense shame, leading to self-imposed isolation and suicidal ideation.

Assessment and formulation:

  • Jasmine’s anxiety about global events manifested in self-blame, a coping mechanism that paradoxically gave her a sense of control (“If it’s my fault, maybe I can fix it by atoning”).
  • The auditory hallucination, which stated, “You are the root of all suffering,” reinforced a longstanding pattern of low self-worth.
  • She had a history of childhood abuse and had developed maladaptive beliefs that “bad things happen because of me.”

Therapeutic process:

  1. Establishing Safety and Trust: Given Jasmine’s trauma history, the first few sessions prioritised stabilisation. The therapist emphasised a compassionate, non-judgmental stance and introduced grounding techniques to manage acute distress.
  2. Psychoeducation on psychosis and trauma: The therapist explained how traumatic experiences could shape core beliefs. They discussed the interplay between stress, anxiety, and psychotic symptoms.
  3. Cognitive restructuring and emotional processing: Jasmine’s core belief was “I cause harm.” The therapist used guided discovery to explore alternative explanations for the pandemic and to address her self-blame:
    • Therapist: “What evidence supports the idea that you alone caused a global pandemic?”
    • Jasmine: “I’ve always felt my negativity causes harm, so this must be another example.”
    • Therapist: “Might there be other factors—like how viruses spread—that could explain the pandemic?”
    • Jasmine: “Yes, I suppose. It’s not just me, but I still feel responsible.”
    • Therapist: “That feeling might be rooted in past experiences. Let’s look at those experiences and see if you truly caused those events, or if you’ve been attributing blame to yourself when it belongs elsewhere.”
  4. Behavioural activation: Jasmine was encouraged to engage in acts of self-care and social connection, such as brief walks and online support groups. This served as a behavioural antidote to her self-isolating tendencies.
  5. Relapse prevention: As Jasmine’s hallucinations and distress subsided, the therapist worked on a plan to identify early warning signs of relapse. They discussed how high-stress events (e.g., watching upsetting news) could trigger old beliefs, and they designed immediate coping strategies to reframe negative thinking before it escalated.

Outcome: Over six months, Jasmine reported a significant reduction in the intensity of the voice blaming her for global events. She began volunteering remotely, found new ways to connect with supportive friends, and gained insight into her maladaptive core beliefs. By the end of therapy, she retained occasional paranoid fears but could challenge them effectively using CBT techniques.

Additional considerations for clinicians

While CBT for psychosis follows the same foundational principles as traditional CBT, several considerations require particular attention:

  • Alliance-building: Individuals with psychosis may harbour feelings of mistrust or paranoia. Building a strong therapeutic alliance with openness, genuine empathy, and non-judgmental acceptance is essential (Morrison, 2017).
  • Flexibility in treatment structure: Standardised protocols are helpful, but the unique nature of delusions and hallucinations calls for creative adaptation. Clinicians should be prepared to deviate from rigid agendas if needed.
  • Trauma-informed approach: A substantial number of individuals with psychosis have histories of trauma. Integrating trauma-informed principles—ensuring emotional safety, recognising triggers, and respecting patients’ boundaries—can greatly enhance therapeutic effectiveness (Larkin & Read, 2008).
  • Integration with other treatments: Medication management, family therapy, and occupational interventions often work synergistically with CBT. Collaboration with psychiatrists, community nurses, social workers, and family members can optimise outcomes.
  • Cultural sensitivity: Interpretations of psychotic symptoms can differ based on cultural and religious backgrounds. Clinicians should explore the patient’s cultural context and avoid pathologising culturally normative beliefs (Achim et al., 2011).
  • Early intervention: The earlier CBT is introduced—particularly in first-episode psychosis or those at high risk—the better the long-term outcomes (French & Morrison, 2008).

Conclusion

Cognitive behavioural therapy for psychosis represents a powerful, evidence-based intervention that extends beyond symptom reduction to address the broader psychosocial challenges faced by individuals with psychotic experiences. By helping patients to test the validity of their beliefs, reduce the distress associated with hallucinations, and develop sustainable coping strategies, CBT can play a critical role in recovery and relapse prevention.

While antipsychotic medication often remains a cornerstone of treatment, the synergistic effect of combining pharmacological intervention with a structured, person-centred, and empathetic psychotherapeutic approach can markedly improve quality of life and functional outcomes. Indeed, the body of research supporting CBT for psychosis continues to grow, underscoring the important role mental health professionals can play in this domain.

For clinicians, successful engagement hinges on empathy, patience, and a willingness to adapt standardised procedures to the patient’s unique symptom profile and context. As both James’s and Jasmine’s stories exemplify, collaborative work, grounded in a robust therapeutic alliance and guided by systematic cognitive and behavioural strategies, can facilitate meaningful change even in the face of entrenched and distressing psychotic symptoms.

Key takeaways

  • CBT for psychosis is rooted in the same foundational principles as standard CBT—identifying and modifying dysfunctional thoughts, beliefs, and behaviours to alleviate distress and improve functioning.
  • Strong empirical support indicates that CBT reduces both positive and negative symptoms of psychosis, improves coping, and can lessen relapse rates.
  • Building a trusting, empathetic relationship is crucial. Individuals with psychosis may be more guarded, necessitating a flexible and respectful approach.
  • A structured approach (with goal-setting, psychoeducation, cognitive restructuring, and relapse prevention) must be complemented by clinical creativity and cultural sensitivity.
  • Many individuals with psychosis have complex trauma histories and may present with co-occurring substance use, anxiety, or mood disorders. Integrating CBT with trauma-informed practices and multi-disciplinary collaboration enhances effectiveness.
  • Techniques like normalisation, Socratic questioning, attention shifting, and behavioural experiments can be tailored to the individual’s specific delusions or hallucinations.
  • CBT for psychosis extends beyond symptom relief to encompass functional recovery, the promotion of social integration, and better quality of life.

References

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