N170

Question 1

Jeffreys (1989)

Answer 1

conducted the first systematic ERP study into the recogntiion of faces.

• 8/9 participants had a peak amplitude in response to face related stimuli, 170 ms after stimulus onset
• face related stimuli varied, including pictures, outline drawings and fragmentary figures
• the stimuli were altered in size and parameter, having virtually no effect on the N170 response.
• this is thought to be because the N170 is the recognition of face related stimuli. when processing the features of a face, the response is thought to shift later in the time domain
• when the stimuli have no relation to faces, no N170 response occurs. the largest response is the P1 representing visual attention to a stimulus.

Question 2

Bentin et al (2006)

Answer 2

found delayed latencies when processing images of scrambled faces.

• this highlights the delayed physiological response when processing the more complex features of a face. when these features are made even more complex, the response takes even longer.
• it also highlights that face processing (N170) is initially at the global level

Question 3

what does this suggest?

Answer 3

by assessing EEG in relation to specific time locked stimuli, it allows us to identify when physiological processes are taking place within the brain, helping identify that more complex stimuli are processed later when looking at a face