Psychology (9685) | Schizophrenia

Welcome to the World of Schizophrenia Study Notes!

Hello future psychologist! This chapter deals with Schizophrenia, one of the most complex and serious mental disorders we study. Don't worry if the terminology seems intimidating at first. We are going to break down the symptoms, the tough process of diagnosis, the biological and cognitive roots, and the treatments, step by step.

Understanding this topic is crucial for evaluating psychological explanations and treatments for atypical behaviour. Let's dive in!

3.3.2 Schizophrenia: Defining the Disorder

Schizophrenia is a severe, long-term mental disorder that affects how a person thinks, feels, and behaves. It often involves a loss of contact with reality (psychosis).

The Two Types of Symptoms

When classifying symptoms, psychologists categorize them into two main groups: Positive Symptoms and Negative Symptoms.

1. Positive Symptoms (Adding something abnormal)

These are experiences that are added to the person's mental life. They reflect an excess or distortion of normal functioning.

• Hallucinations: Distortions or exaggerations of perception. The person perceives things that aren't actually there.
  • Most common example: Auditory hallucinations (hearing voices), but they can also be visual, olfactory (smell), or tactile (touch).
• Delusions: False beliefs that are firmly held despite clear evidence that they are untrue or irrational.
  • Example 1: Delusions of persecution (believing they are being harassed or spied on).
  • Example 2: Delusions of grandeur (believing they are famous, powerful, or have special abilities).

2. Negative Symptoms (Taking away something normal)

These symptoms represent a reduction or loss of normal functions or abilities.

• Speech Poverty (Alogia): A reduction in the amount and quality of speech. The person might have very limited verbal output, giving brief, empty replies.
• Avolition: A reduction, difficulty, or inability to initiate and persist in goal-directed behaviour (like motivation).
  • This can manifest as poor hygiene, lack of energy, or lack of persistence in work or school.

Reliability and Validity in Diagnosis

Diagnosing schizophrenia can be challenging. We need to consider how consistent (reliability) and accurate (validity) the diagnostic process is.

Key Issues Affecting Reliability and Validity

The core challenge is that schizophrenia is defined by a collection of symptoms, not a single biological marker, leading to several potential biases:

1. Culture Bias

Diagnosis often relies on Western classification systems (like DSM-5). Symptoms considered 'abnormal' in one culture may be acceptable or even valued in another.

• Example: In some cultures, hearing voices or communicating with ancestors is seen as a sign of spiritual giftedness, not pathology. This means African-American or Caribbean individuals in the UK may be over-diagnosed because their cultural norms are misunderstood.

2. Gender Bias

If diagnostic criteria are applied differently based on gender, gender bias occurs.

• Women are sometimes under-diagnosed because they are often better at maintaining social functioning than men (known as 'coping'). Clinicians might overlook their symptoms, assuming they are dealing with mild depression or anxiety instead of schizophrenia.

3. Co-morbidity and Symptom Overlap

These two related issues severely reduce the validity of a diagnosis (i.e., how sure we are that the person has only Schizophrenia).

• Co-morbidity: This is when a patient suffers from two or more disorders at the same time.
  • If 50% of schizophrenia patients also meet the criteria for substance abuse or depression, it raises the question: Are we dealing with two distinct conditions, or one single, complex disorder?
• Symptom Overlap: This is when symptoms of schizophrenia are also found in other disorders.
  • Example: Severe confusion and avolition (lack of motivation) are also key features of severe depression or bipolar disorder. If the symptoms overlap significantly, it makes reliable differential diagnosis (telling one illness apart from another) very difficult.

Biological Explanations for Schizophrenia

Biological explanations focus on genetics and neurochemistry, suggesting a physical cause for the disorder.

1. Genetic Explanation

Schizophrenia runs in families, suggesting a genetic vulnerability. It is not caused by a single gene but is polygenic (caused by many genes).

• Evidence: Studies comparing concordance rates (the likelihood of both twins having the disorder) show that identical (MZ) twins have a much higher rate (around 48%) than non-identical (DZ) twins (around 17%).
• Crucial Note: Even MZ twins do not have 100% concordance, meaning genes alone do not cause the disorder. This strongly supports the diathesis-stress model (genetic vulnerability + environmental trigger).

2. Neural Correlates (The Dopamine Hypothesis)

The Dopamine Hypothesis is the most important biological explanation, suggesting that abnormal levels of the neurotransmitter dopamine (DA) in the brain are linked to the onset and symptoms of schizophrenia.

Step-by-Step Dopamine Theory:

1. Original Hypothesis (Hyperdopaminergia): It was first believed that schizophrenia was caused by abnormally high levels (excess) of dopamine activity in the subcortex (deep areas of the brain).
   • This excess DA activity in areas like the Broca’s area (speech production) is thought to cause positive symptoms (like auditory hallucinations).
2. Updated Hypothesis (Hypodopaminergia): Newer research suggests that abnormally low levels (deficit) of dopamine in the cortex (the prefrontal area, associated with thinking and decision-making) may be responsible for the negative symptoms (like avolition and speech poverty).

Key takeaway: Modern psychology sees an imbalance—excess DA in some areas (causing positive symptoms) and deficit DA in others (causing negative symptoms).

Cognitive Explanations: Dysfunctional Thought Processing

Cognitive explanations suggest that schizophrenia results from disruptions in normal thought processes and mental filtering, causing patients to misinterpret information.

Dysfunctional Thought Processing

This approach focuses on the breakdown of cognitive systems. Two key dysfunctional processes are often implicated:

1. Impaired Meta-representation: This is the ability to reflect on your own thoughts and intentions and distinguish them from others' actions.
   • If this system is impaired, individuals might fail to recognize their own internal thoughts or inner voice as being produced by themselves. They might mistakenly perceive them as external voices or commands, leading directly to hallucinations.
2. Impaired Central Control: This is the ability to suppress automatic responses and perform deliberate, goal-directed actions.
   • If central control is impaired, schizophrenic patients often suffer from disorganized speech (tangentiality), jumping between topics because they cannot suppress automatic associations linked to certain words.

Therapies and Treatments for Schizophrenia

Treatments typically involve a combination of biological (drug) therapy and psychological (cognitive) therapy.

1. Biological Therapy: Anti-Psychotic Drugs

Anti-psychotics aim to normalize neurotransmitter activity, primarily dopamine, to reduce symptoms.

A. Typical Anti-Psychotics (First Generation)

• Mechanism: These drugs (e.g., Chlorpromazine) primarily work as dopamine antagonists. They block D2 receptors in the brain.
• Effectiveness: They are effective in reducing positive symptoms (like hallucinations and delusions) by limiting the amount of dopamine that can bind to receptors.
• Side Effects: They have severe side effects, including motor difficulties resembling Parkinson's disease, and potentially irreversible movement disorders like tardive dyskinesia (involuntary facial movements).

B. Atypical Anti-Psychotics (Second Generation)

• Mechanism: These drugs (e.g., Clozapine, Risperidone) also block D2 receptors but also act on serotonin (5-HT) receptors.
• Effectiveness: They temporarily occupy and then rapidly detach from the D2 receptors, reducing the risk of side effects. Critically, they treat both positive and negative symptoms, often by improving function in the prefrontal cortex.
• Side Effects: While generally having fewer severe motor side effects than typical drugs, atypical drugs still carry risks, such as weight gain and, in the case of Clozapine, a rare but serious blood condition called agranulocytosis.

2. Psychological Therapy: Cognitive Therapy (CBT)

Cognitive Behavioural Therapy (CBT) for schizophrenia aims to help patients identify and challenge their irrational thoughts (delusions) and abnormal interpretations (hallucinations).

How CBT Works with Schizophrenia:

1. Assessment: The therapist helps the patient understand the source of their distress (e.g., identifying the content of their delusion).
2. Challenging Delusions: The therapist does not directly dismiss the delusion but helps the patient evaluate the evidence for their belief.
   • For example, if a patient believes they are a secret agent (delusion of grandeur), the therapist might ask, "If you are a secret agent, why are you currently sitting here and not on a mission?"
3. Normalization: The patient learns that hearing voices is an experience shared by many people, reducing anxiety and feelings of uniqueness or hopelessness.
4. Developing Alternative Explanations: The patient is encouraged to test the reality of their beliefs, leading them toward less threatening or dysfunctional interpretations of their symptoms.