Addressing the Impact of Timing Jitter on Visual Evoked Potentials to Faces

Event-Related Potentials (ERP) are EEG responses that are time-locked to external stimuli and reflect underlying cognitive processing. For accurate recording of ERPs, it is necessary to include information about the stimulus. Modern computers introduce variability between the request to render an image to a monitor and when the image actually appears. This jitter may decrease the amplitude of the measured ERP components. Using a light-sensitive diode to detect stimulus onset, we determined how differences in onset timing impact latencies and amplitudes of select ERP components related to visual face processing. Results indicated that the majority of the component amplitudes are impacted with the exception of the EPN. This impact highlights the importance of using objective measures of stimulus onset when using visual stimuli for ERP experiments. [A document with an explanation of the project poster is included as a supplementary file at the bottom of this page.]