Brain & Neuropsychology

• Cell body (soma)


  Contains the nucleus which holds the genetic material

  (DNA) of each neuron.
• Dendrites


  Carries the electrical signal from the neighbouring

  neurons to the cell body (dendrites look like branches)
• Axon


  Carries signals away from the cell body towards other

  neurons.
• Nodes of Ranvier


  Areas of the axon without myelin. The electrical signal

  can jump rapidly which speeds up the signal.
• Myelin Sheath


  Multiple layers of fatty cell membrane that wrap around

  the axon to protect it.
• Nucleus


  The command centre of our cells. (Holds the cells DNA)
• Axon Terminal


  Part of a nerve cell that make

  synaptic connections with the next nerve cell
• Hebb’s Theory of Neuronal Growth

  • Hebb suggested that when we learn, this creates new connections between neurons in our brain
  • Hebb suggested that our brain is ‘plastic’
  • Hebb suggested that learning leaves a trace in our brain
• Localisation of Function - The theory that different brain areas are responsible for specific functions and behaviours.
• Penfield's study

  Aim:

  • To see how patients would respond to different regions of their brain being electrically stimulated.

  Method:

  • Epilepsy patients would lay awake while Penfield stimulated different parts of their brain and treated their epilepsy.
  • Penfield would record their responses.
  • Over 30 years Penfield recorded the responses of over 100 patients.
• penfield study evaluation

  • unusual sample, lacks population validity
  • mixed results in later research, lacks reliability
• tulving's gold memory study AMRC

  aim- investigate if episodic memories produce different blood flow patterns to semantic ones

  method- 6 participants injected with radioactive gold, repeated measures, and monitored blood flow using PET scan

  results- different blood flow in 3/6 participants, episodic in frontal lobe

  conclusion- episodic and semantic memories localised, memory has a biological bias
• tulving's gold memory study evaluation

  • made a conclusion based on just 3 of the participants
  • evidence from brain scans are difficult to fake, producing unbiased evidence
• ct scans - takes lots of x-rays of the brain which are combined to give a detailed picture


  strength: quality higher than traditional x-ray

  weakness: high levels of radiation and only produces still images
• PET scan - patient injected with radioactive glucose, brain activity shown on computer screen


  strength: shows the brain in action and localisation of function

  weakness: expensive and may be unethical because of radiation
• fMRI scan - measures changes in blood oxygen levels, displayed as 3D computer image


  strength: superior as produces clear images without use of radiation

  weakness: expensive and have to stay very still