THE MEDICAL MODEL
It explains that mental illness has a biological cause, hence, could be treated physiologically. Also, the
medical model assumes that patients display.
Biological explanation of mental illness
• Biochemical explanation
o Distorted neurotransmitter levels
• Genetic Explanation
o Inheritance of genes
• Brain Abnormality
o Abnormal structure of the brain
Genetic explanation of mental health
So basically, when people share genes, they are more likely to have similar behavior and
characteristics. Hence, we look at concordance rates (the similarities between individuals).
So, for research to be done based on genetics, who do you believe researchers should conduct
research on?
• People who are genetically related that have a specific disorder (proband)
Genetic Principles
• Family studies:
o First degree relatives should have higher concordance rates than second degree
relatives.
• Because they share more than 50% of their genetic makeup
• Twin studies
o Carrying out studies on MZ and DZ twins in order to see the concordance rates. It is
assumed that these sets of twins share the same background.
, • Adoption studies
o Carrying out studies on individuals who were adopted as children and measuring the
concordance rate between their biological parents (genetics) and their adoptive
parents (environmental)
• Association Studies
• Looking at either individuals who are more vulnerable to a specific disorder; also
known as Candidate-gene association studies (CGAS) or at the entire genome;
known as the Genome-wide association studies (GWAS).
Biochemical explanation of mental illness
• Biochemical explanations focus on the levels of different chemicals in our body.
• This explanation suggests that abnormal levels of certain chemical can cause the symptoms
of a mental health issue (this could be too much of a chemical, or too little)
• Abnormal levels of chemicals = abnormal behavior
• Basically, the brain transmits information in the form of electrical impulses. So, for
information to pass from one cell, it needs neurotransmitters.
• Neurotransmitters are tiny chemical bubbles of information that pass-through neurons. This
information comes in the form of hormones, such as:
o Dopamine and serotonin.
Brain Abnormality explanation of mental illness
Smaller Brain Size
• Patients with schizophrenia have a reduced overall brain size, with less grey matter in total
compared with the neurotypical brains.
• This reduction in grey matter stops when patients take antipsychotic medications.
• This then suggests that the reduced grey matter is associated with aspects of the disorder.
Research evidence
• Study compared 159 people with schizophrenia with 158 healthy people, there can be up to
30% increase in the size of ventricles of patients with schizophrenia.
o Larger ventricles mean less grey matter in the brain, which means less functionality
within the brain.
It explains that mental illness has a biological cause, hence, could be treated physiologically. Also, the
medical model assumes that patients display.
Biological explanation of mental illness
• Biochemical explanation
o Distorted neurotransmitter levels
• Genetic Explanation
o Inheritance of genes
• Brain Abnormality
o Abnormal structure of the brain
Genetic explanation of mental health
So basically, when people share genes, they are more likely to have similar behavior and
characteristics. Hence, we look at concordance rates (the similarities between individuals).
So, for research to be done based on genetics, who do you believe researchers should conduct
research on?
• People who are genetically related that have a specific disorder (proband)
Genetic Principles
• Family studies:
o First degree relatives should have higher concordance rates than second degree
relatives.
• Because they share more than 50% of their genetic makeup
• Twin studies
o Carrying out studies on MZ and DZ twins in order to see the concordance rates. It is
assumed that these sets of twins share the same background.
, • Adoption studies
o Carrying out studies on individuals who were adopted as children and measuring the
concordance rate between their biological parents (genetics) and their adoptive
parents (environmental)
• Association Studies
• Looking at either individuals who are more vulnerable to a specific disorder; also
known as Candidate-gene association studies (CGAS) or at the entire genome;
known as the Genome-wide association studies (GWAS).
Biochemical explanation of mental illness
• Biochemical explanations focus on the levels of different chemicals in our body.
• This explanation suggests that abnormal levels of certain chemical can cause the symptoms
of a mental health issue (this could be too much of a chemical, or too little)
• Abnormal levels of chemicals = abnormal behavior
• Basically, the brain transmits information in the form of electrical impulses. So, for
information to pass from one cell, it needs neurotransmitters.
• Neurotransmitters are tiny chemical bubbles of information that pass-through neurons. This
information comes in the form of hormones, such as:
o Dopamine and serotonin.
Brain Abnormality explanation of mental illness
Smaller Brain Size
• Patients with schizophrenia have a reduced overall brain size, with less grey matter in total
compared with the neurotypical brains.
• This reduction in grey matter stops when patients take antipsychotic medications.
• This then suggests that the reduced grey matter is associated with aspects of the disorder.
Research evidence
• Study compared 159 people with schizophrenia with 158 healthy people, there can be up to
30% increase in the size of ventricles of patients with schizophrenia.
o Larger ventricles mean less grey matter in the brain, which means less functionality
within the brain.
