Biological Approach

• Biological Approach Assumptions


  All behaviour has a biological basis

  Our minds live in our brains

  Brings psychology and physiology together
• Heredity


  Passing of characteristics over generations through genes
• Hereditary


  The idea that a particular trait (eg illness) has been passed on
• Genotype


  Genetic code in DNA of cells
• Phenotype


  Physical appearance resulting from genes
• Concordance Rate


  The likelihood that a person will develop a characteristic, trait, or disorder given that another already has it
• Methods of investigating link between genes and behaviour

  Family studies

  Twin studies

  Adoption studies
• Dizygotic twins


  Share 50% of their genes (fraternal)
• Monozygotic twins


  Share 100% of their genes (identical)
• Gottesman & Shield


  Biopsychologists who compares the concordance for schizophrenia between monozygotic and dizygotic twins
• Gottesman and Shield's findings


  Concordance for monozygotic twins was 42%

  Concordance for dizygotic twins was 9%

  Therefore there is higher concordance for monozygotic twins, providing evidence for a genetic basis of schizophrenia
• Issue with family and twin studies

  They share genes and environment, therefore it is difficult to determine which has influenced them
• Tienari (1991)


  Assessed the development of schizophrenia in adopted children of schizophrenic parents

  Found that 10% developed schizophreni compared to 1% in the control group
• Evolutionary Psychology Assumptions

  Behaviours adapt due to evolutionary pressures

  Innate brain functions and knowledge help us to adapt to our environment

  Behaviour is passed on via genetics
• Natural Selection


  Process whereby those who are best adapted to their environment survive and produce more offspring
• Evolutionary Scientists


  Charles Darwin and Alfred Russel Wallace
• What causes evolution? (3)

  • Environmental pressures and competition eg habitat, food, predation
  • Variation
  • Sexual Selection - those with better adaptions more likely to be selected as mates
• Why might the nervous system be important to psychologists?

  To understand human behaviour such as stress, fight or flight etc
• Parts of nervous system

  Brain

  Spinal cord
• Function of neurons


  They transmit nerve impulses as electrical signals

  Influence many aspects of behaviour eg breathing, eating, sex

  How our nervous system communicates with the body
• Draw and label a neuron


  (Don't need to know soma)

  
• Brain diagram !!


  ...

  
• The temporal lobe influences memory and auditory processing
• The occipital lobe affects visual processing
• The parental lobe affects sensory processing eg touch, taste
• The brain stem is responsible for unconscious behaviours eg breathing, blinking
• The cerebellum controls balance
• Draw and label a pre-synaptic and post-synaptic terminal sending neurotransmitters


  !

  
• Name the parts of the endocrine system

  Pituitary, thyroid, adrenal, and sexual glands, and pancreas