Biological

• Twin Study


  Gottesman+ Shields
• Aim


  To see if Schizophrenia had a genetic basis
• Procedure


  1. 62 twin Sz patients equal m.f

  2. All hospitalised before 1964

  3. 24 mz twins, 33 dz twins

  4. Identified by blood grouping

  5. MH measured using hospital notes

  6. Semi-Structured interviews twins-parents

  7. 30 min tape recording assess language

  8. Personality testing
• Adoption Study


  Kety et al
• Aim


  To see if a genetic basis for Sz by comparing adoptive and bio families of 52 patients
• Procedure


  1. 34 sz patients (mostly Dz twins)

  2. Danish adoption register

  3. Age 20-43

  4. Split into 3 groups: Chronic, Short term, borderline diagnosis

  5. 33 healthy controls matched on age, gender, adoptive age

  6. Tracked down 463 relatives

  7. Relatives diagnosed by psychiatrists who didn't know relationship

  8. Relatives put in 3 categories: B: Adoptive child, D: Diagnosis not clear, C: Inadequate personality
• Evolution says brains and spinal cords are made up of CNS and PNS
• CNS


  • Brain and spinal column
• PNS


  • Travels up to brain, organises response, sends signal to body
• Brain


  • Divided into 2 hemispheres
  • Each divided into 4 lobes: Frontal, Parietal, Temporal, Occipital
  • Cerebellum
  • Spinal Chord
• Frontal lobe


  High cognitive functioning, problem solving, decision making/reasoning, motor skills
• Parietal lobe


  Processing information (from senses), language processing
• Occipital lobe


  Visual processing, colour differentiation, motion perception
• Temporal lobe


  Hearing, language
• Spinal Chord


  Transmission of signals between body and brain
• Evolution says males are adapted for aggression due to testosterone
• Hemispheres


  • Sensory stimulus and motor control of right
  • Speech, language, comprehension, analysis, calculation, time sequencing
  • Sensory stimulus and motor control of left
  • Creativity, spatial ability, face recognition
• Corpus Callosum


  Connects the hemispheres and enables communication
• Hypothalamus


  Regulates eating, drinking, release of sex hormones
• Hippocampus


  Memory consolidation, navigation, spatial awareness
• Thalamus


  Relay stations that pass on information from the senses
• Amygdala


  Emotional responses, memory, decision making
• Basal Ganglia


  Movement planning, habit learning
• Brain Scanning Techniques


  PET Scans, CAT Scans, fMRI Scans
• PET scans produce 3D images of how the brain functions by injecting a radioactive tracer into the blood stream
• CAT scans produce cross-sectional 2D images that can be converted to 3D
• fMRI scans measure brain activity by detecting changes in blood flow
• Scans cannot be used on those with pacemakers
• Supporting evidence from brain scanning techniques


  • Murderers had asymmetrical functioning of amygdala compared to control group
  • Those with brain injury more likely to have post-traumatic aggression
  • Gamers showed lower levels of activity in relation to pictures of negative emotion than control group
• Classic Study Raine et al


  Murderers pleading NGRI would show dysfunction in areas associated with violence
• Procedure


  1. 41 murderers (39 male, 2 female) pleading NGRI

  2. 41 controls matched on age, gender, diagnosis of Sz

  3. Screened for general health, psychiatric interview

  4. Performed a CPT task for 10 mins

  5. Injected with radioactive tracer

  6. Completed CBT for 32 mins

  7. Had a PET scan
• Axon terminals


  • End of neuron makes synaptic connection with another neuron (contains neurotransmitters)
• Cell body


  • Contains cell nucleus and genetic information as well as mitochondria
• Dendrites


  • Receives messages from other neurons to trigger electrical impulses
• Axon


  • Extension of the cell body which electrical impulse passes down
• Myelin sheath


  • Fatty deposits that provide an insulating layer and speed up transmission
• Nodes of Ranvier


  • Break along the myelin sheath on cell nodules to speed up transmission
• Neurotransmitters


  Chemical messages that act between the neurons in the brain and allow the brain to process thoughts and memories
• Dopamine


  Related to emotion and cognitive functioning
• Serotonin


  Deals with mood control, feeling pain, sleep, hunger