Schizophrenia Flashcards
All of the explanations of schizophrenia and exam question layouts/techniques
What is schizophrenia?
Schizophrenia is a profound disruption of cognition and emotion, which affects a person’s language, thought, perceptions and sense of self.
What is meant by ‘positive’ symptoms of schizophrenia?
Positive symptoms: behaviours that have no psychological counterpart - they are in addition to a person’s ‘normal behaviour’.
What is meant by ‘negative’ symptoms of schizophrenia?
Negative symptoms: Behaviours that are a reduction in ‘normal functioning’ - they take away from a person’s ‘normal’ behaviour
What are the positive symptoms of schizophrenia?
Hallucinations, delusions and disorganised thinking
What are hallucinations? What are the most common hallucinations?
Hallucinations are unusual sensory experiences.
-Can be related to environmental stimuli or completely random
-Hallucinations can occur in any of the senses
-Auditory hallucinations are the most common, e.g. hearing voices
-Visual hallucinations involve seeing things that aren’t there or seeing distorted facial expressions for example
-Hallucinations can also be olfactory (sense of smell) or tactile (touch)
What are delusions? What are the most common delusions seen in people with SZ?
Delusions are strongly held false beliefs that are persistent even when there is evidence against them.
-Persecutory delusions: the belief that one is going to be harmed, harassed, etc by an individual or organisation i.e. believing that the police are after them, or that family members are special officers out to kill them (most common)
-Referential delusions: the belief that certain gestures, comments and environmental cues are directed at oneself i.e. believing that people are laughing at them (also common)
-Grandiose delusions: the belief that one has excessive fame, wealth or special powers.
What is disorganised thinking? What are some examples of disorganised thinking common in those with SZ?
Disorganised thinking is the result of abnormal thought processes.
-Patient has trouble organising thought processes, which then manifests in speech. This can be quickly switching between topics (derailment), sometimes mid-sentence or speaking gibberish (word salad).
-People with SZ often report that their thoughts are not their own (thought insertion) and are believed to have been inserted by a third party.
-Answers to questions may be indirectly related or completely unrelated (tangentiality).
What are the negative symptoms of schizophrenia?
Flat affect, avolition, alogia, anhedonia and catatonic behaviour
What is the flat effect? (SZ)
-Reduction in range and expression of emotion, e.g. facial expression, eye contact, body language.
-Lack of prosody (intonation and tempo) in speech.
What is avolition? (SZ)
-Difficulty beginning or keeping up with goal-directed activity
-Loss of motivation to carry out day to day tasks
-Andreason (1982) identified 3 signs of avolition: poor hygiene, lack of energy, lack of persistence in work or education
What is alogia? (SZ)
-The focus is on the reduction in amount and quality of speech.
-“Name as many animals as you can in 1 minute” - patients with speech poverty would struggle with this task, not through lack of knowledge, but just struggling to spontaneously produce the words.
What is anhedonia? (SZ)
Loss of pleasure from all activity. This can include eating, social contact or activities the patient used to find pleasure in.
What is catatonic behaviour? (SZ)
-Can range from fast, repetitive movements to no movement at all
-Unexpected gestures and loud utterances
-Echopraxia: mimicking the movement of those around them
-Rigid and unnatural postures - immobile for long periods of time
What are some prodromal symptoms of schizophrenia? (Symptoms that indicate the onset of SZ).
-A loss of interest in usual activities
-Avoiding the company of others
-Staying away from work or school
-Being irritable and oversensitive
-Lack of interest in personal appearance and hygiene
-Generalised anxiety
-Mild degrees of depression
What are the requirements for a schizophrenia diagnosis through DSM-V?
Symptoms occur over at least a 1 month period
6 months of deterioration of functioning
Two or more of the following have to be present for a diagnosis:
Delusions
Hallucinations
Disorganised speech
Disorganised/ catatonic behaviour
Negative symptoms
What are the requirements for a schizophrenia diagnosis through ICD-10?
At least 1 month of symptoms being present to diagnose SZ
At least 1 symptom from category 1 (thought echo/broadcasting and delusions/hallucinations) OR at least 2 category 2 (persistent hallucinations and fleeting delusions, disorganised speech, catatonic behaviour or negative symptoms).
A typical exam question is:
Q) Describe the characteristics of behaviour that lead to a diagnosis of schizophrenia [10]
How would you answer this?
-Outline the difference between positive and negative symptoms
-Explain 2 positive symptoms MINIMUM with detailed examples of each
-Explain 3-4 negative symptoms with detailed examples of each
Another example of a typical exam question:
Q) Ronald has not been feeling the same lately. He told his friend Rory what he has been experiencing. Rory suggested that the behaviours Ronald is showing could be characteristics of schizophrenia.
Describe the characteristics of schizophrenia that Ronald may have told Rory he was experiencing. [15]
How would you answer this?
To get marks for AO1 (description -10 marks):
-Outline the difference between positive and negative symptoms
-Explain 2 positive symptoms MINIMUM with detailed examples of each
-Explain 3-4 negative symptoms with detailed examples of each
To get marks for AO2 (linking to question - 5 marks)
-Reference Ronald or Rory as the characteristics are described, e.g. “Ronald may have told Rory that he is hearing voices that he doesn’t recognise. Rory could believe that Ronald is experiencing auditory hallucinations”
What are the two biological explanations of schizophrenia?
The genetic explanation and the dopamine hypothesis
Explain the main idea of the genetic explanation of schizophrenia.
This explanation believes that schizophrenia is inherited through genes passed down through families. This is investigated through twin, family and adoption studies.
What are some examples of supporting research for family studies of schizophrenia?
Kendler et al (1985) found that first degree relatives of those with schizophrenia are 18 more times at risk than the general population.
Kety et al (1962) The Copenhagen high risk study:
207 children whose mothers had schizophrenia (high risk group) and 104 children with healthy mothers (low risk group) aged between 10-18 years old were matched based on age, gender, their parent’s socio-economic status, and whether they lived in an urban or rural setting. Schizophrenia was found in 16.2% of the high risk group and only 1.9% of the low risk group.
What are some examples of supporting research for twin studies of schizophrenia?
Gottesman and Shields (1972) found a concordance rate of 42% for MZ (identical twins) and 9% concordance rates for DZ (fraternal twins).
Torey (1992) argued that twin studies were inadequate. He found from re-assessing eight previous studies that the concordance rate for the MZ twins was 26% compared with only 6% for DZ.
Cardno et al (1999) found a 40% concordance rate in MZ twins compared with 5.3% in DZ twins.
What are some examples of supporting research for adoption studies of schizophrenia?
Heston (1966) compared 47 children of schizophrenic mothers, who were adopted into non-SZ families, before the age of one month with a control group of 47 children (with no biological SZ mother) raised by non-SZ families. 10% of the children with schizophrenic mothers developed it themselves whereas none of the children from the control group did.
Tienari et al (1987) compared 112 cases of adopted children who had biological mothers who had been diagnosed with schizophrenia with 135 adopted children who had non-schizophrenic biological mothers. 7% of the 112 children whose biological mothers had SZ developed schizophrenia compared to 1.5% of the control group.
A typical exam question for the genetic explanation of schizophrenia is:
Q) Briefly describe one biological explanation for schizophrenia [5]
How would you answer this?
-Introduce the explanation, i.e. “This explanation believes that schizophrenia is inherited through genes passed down through families.”
-Explain that SZ is explored through family studies, twin studies and adoption studies
-Give examples of research (you only have to remember one or two from each), what they did, what they found and why this suggests SZ is genetic
Another typical exam question for the biological explanations of schizophrenia is:
Q) Evaluate one biological explanation of schizophrenia [10]
How would you evaluate the genetic explanation of SZ?
+ve Supporting evidence
P: One strength of the genetic explanation of SZ is that there is research on families that supports the influence of genes on the onset of SZ.
E: For example, Gottesman (1991) found that the closer the genetic relationship to someone with SZ, the higher the likelihood of SZ developing. For example, the occurrence of SZ in the general population is approximately 1%, but if you have a parent with SZ, this jumps to 6%.
C: However, research has shown that 63% of people diagnosed with schizophrenia do not have any family history of schizophrenia in first-degree (parents and siblings) or second-degree (grandparents, aunts, and uncles) relatives.
L: Therefore, even though Gottesman’s research suggests that there is a genetic influence on the development of SZ, the findings across studies are inconsistent, leading us to question the reliability of the genetic explanation of SZ.
-ve Hard to separate nature and nurture
P: One weakness of the genetic explanation of SZ is that it is hard to separate nature and nurture.
E: Family studies/twin studies - participants share similar or the same environment as they live together
E: Therefore it is hard to know whether the development of SZ is down to shared genetics or a shared environment
L: This is a weakness of the genetic explanation as…
-ve Concordance rates are not 100%
P: One weakness of the genetic explanation is that the concordance rates within twin studies are not 100%.
E: Cardno et al (1999) - concordance rate of less than 50%
E: This means that there must be another influence of the development of SZ, not just genetics.
L: This is a weakness of the genetic explanation of SZ, as it fails to provide a full explanation of the cause of SZ, as clearly genetics only play a part in the onset of SZ and other factors must be considered.
Conclusion:
State whether or not the genetic explanation is a useful explanation of the development of SZ. Why/why not? How could it be improved?
Explain the initial hypothesis of the dopamine explanation of schizophrenia.
The brains of schizophrenic patients produce more dopamine than normal brains. It is this increased dopamine that is believed to be responsible for some of the symptoms of the disorder.
What supporting evidence is there for the initial dopamine hypothesis of SZ?
Falkai et al (1988) Autopsies found that people with schizophrenia have a larger than usual number of dopamine receptors. They found an excess of dopamine in the left amygdala. Concluded that dopamine production is abnormal for schizophrenia compared to “normal controls”.
People suffering from Parkinson’s disease were given the drug L-Dopa. L-Dopa raises dopamine activity in the brain, reducing Parkinsonian symptoms. Patients began to develop schizophrenic symptoms.
PET scans: Lindstroem et al (1999) L-Dopa was administered to 10 patients with schizophrenia and 10 controls. L-Dopa stayed in the brain of schizophrenic patients for longer (their synapses didn’t absorb it because the D2 receptors inhibited the transmission). This suggests that schizophrenics have excess levels of dopamine because they have more dopamine receptors.
Drug use: LSD/Amphetamines (chemically similar to dopamine) increase the effects of dopamine in the brain. Large quantities lead to delusions and hallucinations - characteristics associated with SZ. If drugs are taken by SZ patients, their symptoms get worse.
What is the revised dopamine hypothesis of the dopamine explanation of schizophrenia?
Two pathways connecting the limbic system to the cortex and other structures have been found to be implicated in the development of positive and negative symptoms of SZ.
What are the two pathways in the dopamine hypothesis that have been linked to the onset of SZ?
Mesolimbic pathway - positive symptoms
Mesocortical pathway - negative symptoms
The mesolimbic pathway runs from the VTA –> NTA. Too much dopamine in this pathway causes overstimulation, leading to positive symptoms like hallucinations and delusions. Antipsychotic drugs that reduce dopamine transmission (D2 receptors) target this pathway, reducing positive symptoms.
The mesocortical pathway runs from the VTA –> frontal lobe. This pathway is important for emotional response and motivation. Not enough dopamine in this pathway (D1 receptors) leads to the negative symptoms of SZ.
How can the dopamine hypothesis be applied to methods of modifying schizophrenia?
Dopamine hypothesis = Antipsychotics
Antipsychotics are drugs developed to treat disorders like SZ by targeting the release of neurotransmitters at the synapse. Typical antipsychotics were developed based on the dopamine hypothesis and work by blocking the transmission of dopamine on the postsynaptic neuron, which leads to a reduction in neural activity. This then leads to a reduction in positive symptoms like hallucinations and delusions.
A typical exam question for the dopamine explanation of SZ is:
Q) Describe one biological explanation for schizophrenia [10]
How would you answer this?
-One explanation for schizophrenia is the dopamine hypothesis.
-Initially it was believed… (briefly explain the initial dopamine hypothesis - the idea of too much dopamine). Give one piece of evidence to support this e.g. Falkai (1988) Autopsies.
-However, the dopamine hypothesis has advanced in recent years.
-Two pathways have been found to be implicated in the development of positive and negative symptoms of SZ
-Explain what the two pathways are and the difference in dopamine transmission.