Biological Approaches

• What are the assumptions of the biological approach?

  Everything psychological is at first biological We need to look at structures and processes in the bodyMind lives in the brain
• What is neurochemistry?

  The action of the chemicals in the brain which regulate psychological functioning
• Neural means?


  The brain
• What does much of our behaviour rely on?

  Chemical transmissions in the brain, this occurs through neurotransmitters
• What are neurotransmitters?

  Chemical messengers in the brain
• What are examples of neurotransmitters?

  Dopamine, serotonin, acetylcholine, adrenaline
• What has an imbalance of neurochemicals been implicated in?

  Cause of mental illnessesLow levels on serotonin - OCDOverproduction of dopamine - schizophrenia
• What is used to see if characteristics have a genetic basis?

  Twin studies
• What is concordance rate?

  The likelihood that if the trait is found in one twin it will be found in the other
• What are monozygotic (MZ) twins?

  IdenticalOne eggShare 100% of DNA
• What are dizygotic (DZ) twins?

  Non-identicalTwo eggs Share 50% of DNA, the same as siblings
• Example of concordance rate - schizophrenia

  MZ: 50%DZ: 10-19%Fischer, 1971
• Example of concordance rate - OCD


  MZ: 87%DZ: 47%Carey and Gottesman, 1981
• Twin studies evaluation

  Environment may not be the same for the twins
• What is a genotype?


  A person's genetic makeup
• What is a phenotype?


  The way in which genes are expressed, affected by environment
• What is PKU?

  Genetic disorder that can cause learning difficulties, detected by heel prick test, treated with restricted diet
• How does PKU illustrate genotypes and phenotypes?

  Shows children may be born with a predisposition as a genotype but the environment effects the expression of the phenotype
• Evolution

  Darwin, natural selection, pass down the good traits
• Strengths of the biological approach

  Real world applicationScientific methods
• Why is "real world application" a strength of the biological approach?

  Antidepressant medication as treatments for depressionBiological research used Applied to real life mental illness
• Why is "scientific methods" a strength of the biological approach?

  Use objective methods such as scanning techniques Technological advances allow for non-subjective research Produces objective reliable data
• Weaknesses of the biological approach

  Antidepressants don't work for everyoneDeterministic
• Why is "Antidepressants don't work for everyone" a weakness of the biological approach?

  Studies have found wide variations in effectiveness of the drugsResearchers found that they were more effective than placebos but the effects were mainly modestNeurochemistry cant alone explain behaviour
• Why is "Deterministic" a weakness of the biological approach?

  Sees human behaviour as governed by internal genetic causes, ignores environmental influenceMZ twins don't look and act the sameToo simplistic as it ignores effects of the environment