ERPs

• Event-related potential (ERP) 


  Very small voltage changes in the brain that are triggered by specific events or stimuli.

  To find a specific response to a target stimulus requires many presentations of the same stimulus, these responses are then averaged together.

  Any extraneous neural activity will not occur consistently
• ERPs

  Divided into two categories:

  Waves occurring within first 100 milliseconds after presentation of stimulus are termed sensory as they reflect initial response.

  ERPs after 100 milliseconds reflect the way in which the participant evaluates the stimulus
• Strengths of ERPs

  • Can measure neural processes more accurately and tell researchers how processing is affected by a specific experimental manipulation
  • High temporal resolution - led to a widespread use in the measurement of cognitive functions
• Weakness of ERPs

  • Background noise and extraneous material must be completely eliminated which may not always be easy to achieve
  • Important electrical activities occurring deep in the brain are not recorded