Biological Approach

• Central nervous system

  Brain and spinal cord
• Peripheral nervous system


  Nerves throughout the body
• The brain is divided into 2 _______________

  Hemispheres
• The 2 hemispheres are joined by the ________ ___________

  Corpus callosum
• Cerebral cortex

  The outer wrinkly part of the brain
• 4 lobes that each hemisphere is divided into

  - frontal

  - parietal

  - temporal

  - occipital
• Frontal lobe

  Thoughts & personality
• Parietal lobe


  Movement
• Temporal lobe


  Language
• Occipital lobe


  Vision
• 3 sub-cortical areas

  - hippocampus

  - hypothalamus

  - thalamus
• Hippocampus


  Involved with emotions & memories
• Hypothalamus


  Involved with maintaining body systems
• Thalamus


  Sends information from the senses to the correct parts of the brain
• Localisation of function


  Certain areas of the brain have specific functions
• 2 things Darwin suggested


  - species have all evolved from simple life forms

  - evolution occurs through natural selection
• What does natural selection suggest?

  Individuals in a species show a wide range of variation due to differences in their genes - individuals with best suited characteristics are more likely to survive
• Genes


  Carry instructions for the characteristics
• Genotype


  Genetic makeup
• Phenotype

  Observable characteristics
• 2 types of family studies

  Twin studies and adoption studies
• In twin studies psychologists look for ____________

  Concordance
• Concordance


  The number of second twins who have a particular characteristic given that the first one has it
• 2 key problems with twin studies

  - finding twins where both are willing to take part is difficult so leads to small samples

  - twins usually grow up in the same environment so similarities in behaviour could be due to nurture rather than nature
• Monozygotic twins


  Twins who form from one egg, are identical, have the same genes and are always the same sex
• Dizygotic twins

  Twins who form from 2 eggs, are non-identical, have 50% of the same genes and can be male/female
• What do adoption studies look at

  A person has a certain characteristic and both biological and adoptive parents are looked at to see if they have the characteristic
• 3 hormones that are involved with behaviour

  - oxytocin

  - testosterone

  - cortisol
• Oxytocin

  Positive feelings
• Testosterone


  Aggression
• Cortisol


  Stress
• Neurons


  Nerve cells that are the building blocks of behaviour
• Neurons send ________________ to the brain

  Electrochemical messages
• Neurotransmission


  The process by which electrochemical messages are sent
• Synapse

  Gap between 2 neurons
• Neurotransmitters


  The body's natural chemical messengers
• Strengths of the biological approach (2)

  - methods used produce replicable and reliable data

  - understanding neurotransmitters can help to understand mental illness and treatments
• Weaknesses of the biological approach (2)

  - deterministic so suggests we have no control over our behaviour

  - reductionist so may miss some of the wider influences