Post Mortem, FMRI, EEG - A01

• Post Mortem Examinations - one way of studying the brain, used to establish underlying neurobiology of particular behaviour, these areas of damage are examined after death as means of establishing cause of affliction individual has suffered.
• Functional Magnetic Resonance Imaging (fMRI) - works by measuring changes in blood flow using magnetic field / radio waves in particular areas of brain which indicates increased neural activity, if particular area of brain more active there is an increase in oxygen demand in that area which is why blood travels with oxygen to these areas. This is why researchers are able to produce maps showing which areas if the brain are involved in particular mental activities.
• Electroencephalogram (EEG) - measures specifically electrical activity in the brain, electrodes placed on the scalp which detects small electrical changes resulting from activity of brain cells, when electrical signals from different electrodes are graphed over a period of time the resulting representation is EEG. There are 4 basic patterns which are Alpha, Beta, Delta, Theta waves.
• Event Related Potentials (ERPs) - small voltage changes in brain that are triggered by specific events or stimuli (eg while watching violent video). Difficult to pick up signals specific to target stimulus from all the other electrical activity being generated at given time. To establish specific response to target stimulus, many responses to stimulus averages. ERPs divided into 2 categories:

  • Sensory ERPs - reflect an initial perception of physical characteristics of stimulus
  • Cognitive ERPs - demonstrates information processing in response to stimulus