FMRI's

• Functional Magnetic Resonance Imaging (fMRI)

  1. Looks at areas of brain most active when person performs a task

  2. Measures blood flow in brain using radio waves and magnetic field, neurons most active require more O2 and glucose therefore inceased demand so increased bloof flow

  3. Produces maps showing which areas of the brain are involved in a particular mental activity

  4. Takes a 'photo/3D map' of the areas of high oxygen use before a task (baseline measure)

  5. Takes a 'photo/3D map' of the areas of high oxygen use during a task
• Neurons most active when person is doing a task

  Using most energy so requires glucose and oxygen carried into bloodstream
• Particular area of the brain becomes more active


  Increased demand for oxygen in that area
• Increased demand for oxygen


  Brain responds by increasing blood flow, delivering oxygen in the red blood cells
• Difference between the two recordings (before and during task)


  Only to do with the activity associated with the task
• AO3


  -non invasive- a lot of other techniques involve things such as injecting potentially harmful radioactive material,

  if administered correctly it is straightforward to use and can produce images which have very high spatial resolution.

  strength as is it virtually risk free and produces clear images HOWEVER, has poor temporal resolution as there is approximately a five second time lag between image on screen and neurons initial firing, so may not truly represent moment to moment firing
• AO3

  FMRI scans are the most expensive way of measuring the brain,this means that it is very expensive to carry out research that uses fMRI with multiple participants, maybe multiple times.This may then result in fMRI scans not being used or only small sample sizes being possible in research.This then makes research less valid, recent research has shown the fMRI scans are better than polygraphs (measure anxiety through respiration and skin temperature changes) at detecting when people are lying.  A Californian company called No Lie MRI claims they can detect lies 90% of the time.