Psychosis and Schizophrenia

University of Exeter PSY1204: Psychosis and Schizophrenia

Dr. Gina Collins - November 2025

Trigger Alert

  • This lecture includes discussions that may touch upon sensitive topics, including violence and homicide related to psychosis and schizophrenia.

  • The information is handled carefully to minimize stigma, but students are advised to prioritize their wellbeing and take breaks as needed.

Lecture Overview

  • By the end of this lecture, you will be able to:

    • Define psychosis and schizophrenia.

    • Identify symptom domains: positive and negative symptoms.

    • Describe biological and psychosocial factors relating to schizophrenia.

    • Understand evidence-based interventions including CBTp (Cognitive Behavioral Therapy for psychosis), family therapy, medication, and early intervention in psychosis (EIP).

Understanding Psychosis and Schizophrenia

  • Definition Inquiry: What do psychosis and schizophrenia mean to individuals? (Engagement via https://www.menti.com/alcj1brs8ojr)

Media Representations of Schizophrenia

  • Negative portrayals emphasize:

    • Violence

    • Unpredictability

    • Homicidal behavior

    • Dangerousness

    • “Madness” stereotypes

Current Events: Schizophrenia in the News

  • Cases often seen in mental health services include:

    • Notable histories such as low adherence to medication and prior criminal damage but deemed low risk.

    • A documented manslaughter conviction with diminished responsibility raises questions of accountability.

Statistical Insights on Homicide and Mental Health

  • According to Shaw et al. (2020):

    • Only 8% of homicide convictions in England and Wales had prior contact with mental health services.

    • Of those, less than 25% had a diagnosis of schizophrenia; the majority had diagnoses related to:

    • Personality disorders

    • Substance abuse (drugs/alcohol)

    • People with schizophrenia are no more likely to commit violent crimes than the general public.

    • A critical risk factor: 10% of individuals with schizophrenia die by suicide.

Positive Representations of Psychosis

  • Positive impressions include:

    • Individuals leading meaningful, loving, and productive lives.

    • Emphasis on relationships and community, supporting humanization and stigma reduction.

Understanding Psychosis

  • Definition:

    • A combination of psychological symptoms leading to a loss of contact with reality.

  • Prevalence:

    • Approximately 1% of the population (PHE, 2016).

    • Peak onset: Males in their teenage years to mid-20s; females from teenage years to late 20s.

  • Features:

    • Present in various psychiatric, neuropsychiatric, and medical conditions with high distress potential for affected individuals and their families.

  • Description:

    • Inability to distinguish between internal mental experiences and external reality.

Domains of Psychosis

  • Abnormalities may be noticed across five domains:

    • Hallucinations

    • Delusions

    • Disorganized thoughts

    • Disorganized behaviors

    • Negative symptoms: Decrease or loss in normal functioning.

  • Common features include illogical thought processes, tangentiality, neologisms, thought blocking, and catatonia.

Hallucinations

  • Definition: False perceptions without external stimuli. Types include:

    • Auditory (most common)

    • Visual

    • Olfactory

    • Gustatory

    • Tactile

    • Nociceptive

    • Thermoceptive

    • Proprioceptive

  • Association with Schizophrenia: Auditory hallucinations typically involve commands or third-person comments.

  • Linked to other conditions such as bipolar disorder and PTSD.

Notable Quotes About Hallucinations

  • Patricia Deegan: "Hearing voices is not like imagining someone speaking…"

  • Elyn Saks: "The voices…commanding. They were not me — and yet somehow, they lived inside my mind."

  • Virginia Woolf: "The world wavered and quivered…"

Delusions

  • Definition: Fixed, false beliefs maintained despite contradictory evidence. Types include:

    • Bizarre delusions: Clearly implausible beliefs (e.g., MI5 stealing genes).

    • Non-bizarre delusions: Possible beliefs lacking evidence (e.g., MI5 is looking for you).

  • Primary vs. Secondary Delusions:

    • Primary delusions are ambiguous and linked to severe illnesses like schizophrenia.

    • Secondary delusions correlate with emotional states (e.g., paranoia in substance use).

Categories of Delusions

  • Persecutory Delusions: Individual believes they are being followed or targeted.

  • Delusions of Infidelity: Overwhelming jealousy about a partner presumed unfaithful.

  • Referential Delusions: Belief that common events pertain directly to the individual.

  • Grandiose Delusions: False beliefs of greatness or supernatural powers.

  • Erotomanic Delusions: Belief that someone, often of stature, is in love with the individual.

  • Religious Delusions: Involves non-mainstream religious beliefs.

  • Nihilistic Delusions: False beliefs that aspects of self or reality do not exist.

  • Somatic Delusions: Focus on bodily functions or appearance.

  • Delusional Parasitosis: Belief of being infested with parasites or insects (Julayanont & Suryadevara, 2021).

Disorganised Thoughts and Behaviors

  • Disorganized Thoughts:

    • Non-linear or circumstantial thinking.

    • Tangential thoughts.

    • Word salad.

  • Disorganized Behaviors:

    • Emotional responses that are unpredictable or inappropriate.

    • Nonsensical actions considered socially unacceptable.

    • Catatonic behavior, showing diminished responses to the environment.

Negative Symptoms of Schizophrenia

  • Represent a deterioration in normal functioning, often confused with depression and include:

    • Avolition: Lack of motivation.

    • Alogia: Poverty of speech.

    • Anhedonia: Loss of pleasure.

    • Flat Affect: Lack of emotional expression.

    • Psychomotor Retardation: Decreased energy levels.

    • Catatonia: A state of unresponsiveness.

Symptom Classification Exercise

  1. “I hear voices commenting on what I’m doing.” ➔ Positive

  2. “I feel no motivation to do anything anymore.” ➔ Negative

  3. “I believe my thoughts are being broadcast to others.” ➔ Positive

  4. “I’m convinced that strangers are plotting against me.” ➔ Positive

  5. “I barely feel any emotion these days.” ➔ Negative

  6. “I’m convinced that my neighbor is spying on me.” ➔ Positive

  7. “I keep losing my train of thought mid-sentence.” ➔ Cognitive

  8. “I smell things that no one else can smell.” ➔ Positive

  9. “I rarely speak unless someone forces me to.” ➔ Negative

  10. “I find it difficult to remember things I’ve just learned.” ➔ Cognitive

Schizophrenia Spectrum and Other Psychotic Disorders

  • These disorders include:

    • Schizotypal (personality) disorder

    • Schizophrenia

    • Schizoaffective disorder

    • Schizophreniform disorder

    • Delusional disorder

    • Brief psychotic disorder

    • Substance or medical-induced psychotic disorder

  • Common symptoms across disorders consist of delusions, hallucinations, and cognitive disorganization.

DSM V Diagnostic Criteria for Schizophrenia

  • Characteristic Symptoms:

    • Must include two or more symptoms for at least one month (with at least one from 1, 2, or 3):

    • Delusions

    • Hallucinations

    • Disorganized speech

    • Grossly disorganized or catatonic behavior

    • Negative symptoms

  • Functional Impairment: Markedly lower functioning in at least one major area (e.g., work, relationships).

  • Duration: Continuous signs for at least six months, may include prodromal or residual phases.

  • Differential Diagnosis: Schizoaffective disorder and mood disorders with psychotic features must be ruled out.

Prevalence and Subtypes of Schizophrenia

  • Schizophrenia affects approximately 24 million people, or 0.32% of the global population (WHO, 2022).

  • Common subtype descriptions include:

    • Paranoid Type: Dominated by delusions and hallucinations.

    • Catatonic Type: Withdrawn behavior mixed with sporadic episodes of agitation.

    • Disorganized Type (Hebephrenic): Bizarre speech and behavior not matching social cues.

Diagnosis: Challenges and Considerations

  • Emotional situations can lead to sensory experiences similar to those in psychosis, i.e., bereavement may induce vivid flashbacks.

  • Environmental cues may trigger misinterpretations of normal auditory or visual stimuli, particularly in ambiguous situations.

  • Relatable feelings, such as sensing one is being watched, may not reach psychotic levels but can cause distress.

  • The influence of religion on psychotic experiences is significant; sometimes culturally accepted beliefs are misinterpreted clinically.

Bio-Psychosocial Understanding of Schizophrenia

  • Biological Factors:

    • Genetics, biochemistry, and neurology.

  • Psycho-social Factors:

    • Social determinants, systemic factors, and sources of psychological stress.

Genetic Research on Schizophrenia

  • Twin Studies by Gottesmann & Shields (1972):

    • Investigated concordance rates among monozygotic (MZ) vs. dizygotic (DZ) twins.

    • MZ twins showed approximately 42% concordance for schizophrenia, while DZ twins had about 9%.

  • Adoption Studies by Heston (1966):

    • Higher risk of schizophrenia in individuals with a diagnosed biological mother despite different environmental upbringing.

Dopamine Hypothesis in Schizophrenia

  • The dopamine hypothesis: Dysregulated dopaminergic systems play a pivotal role in the manifestations of schizophrenia.

  • Increased presynaptic dopaminergic activity associated with hallucinations and delusions. Antipsychotics act primarily on dopamine D2 receptors.

  • Modern models recognize dopamine dysregulation as integrating genetic, environmental, and neurodevelopmental factors.

Neurological Development and Risk Factors

  • Studies show that perinatal complications greatly heighten schizophrenia risk.

  • Research by Ursini et al. (2018): Polygenic risk factors indicated magnified schizophrenia risk (5x) with perinatal complications, while ease of other environmental interactions was noted.

Substance Influence on Schizophrenia

  • Studies suggest that avoiding cannabis use could potentially prevent approximately 8% to 24% of first-onset psychosis cases across various nations.

Socio-economic Factors and Stress

  • Socioeconomic challenges, such as poverty and lack of resources, significantly correlate with schizophrenia.

  • Major life stressors, including bereavement or divorce, are triggering factors for symptom onset.

Family Dynamics and Psychosis

  • High Expressed Emotion (EE) within families often exacerbates symptoms.

  • Only around 10% of individuals from low EE homes relapse compared to significantly higher rates in high EE environments.

Racial Disparities and Diagnosis

  • Notably higher prevalence (5%) of schizophrenia among young Black men in South London attributed potentially to societal racism rather than genetic predisposition.

Treatment Approaches for Schizophrenia

  • NICE Guidelines (2014):

    • Emphasize early intervention in psychosis services, involving both antipsychotic medications and psychological interventions like family therapy and individual CBT.

    • Crisis resolution teams are recommended to provide support during acute episodes.

Types of Antipsychotic Medications

  • First Generation Antipsychotics:

    • Side Effects: Extrapyramidal symptoms including dystonia, akathisia, weight gain, sedation, etc.

  • Second Generation Antipsychotics:

    • Examples and Side Effects include:

    • Clozapine: Risk for agranulocytosis and cardiotoxicity.

    • Olanzapine: Weight gain, sedation.

    • Risperidone: Hypertensive responses and other classic sympathomimetics.

Psychological Interventions

  • Most effective interventions include family therapy, psychoeducation, and CBT, all vital in reducing symptoms and relapse risks.

  • Future Directions: Need for more comprehensive treatments and validation of multi-element approaches.

Interview with Dr. Daniel Maughan

  • Position: Consultant Psychiatrist and clinical lead for the Early Intervention in Psychosis Service, Oxfordshire.

Conclusions

  • Schizophrenia stems from a complex interplay of multiple causes.

  • Importance of understanding individual experiences and providing families with support strategies.

  • Advancements needed in medications, interventions, and social equality to improve patient outcomes and quality of life.