Tobii Pro WorkshopsPresenter: Dr. Louisa Kulke
4 January 2017, 8:30-10:00
Fee: EUR 20
Setting up combined eye-tracking and EEG
Combining eye-tracking and Electroencephalography (EEG) can be a useful technique to investigate brain mechanisms of free viewing, to investigate neural responses in infant-friendly paradigms relying on gaze-contingency or to simply ensure fixation during presentation of visual stimuli. Especially in infant research, where verbal instructions are often not possible, non-verbal eye-tracking paradigms can provide useful insights to cognitive processes. However, eye-movements cause large artifacts in EEG data, making it tricky to combine both. This workshop will provide an introduction to combining eye-tracking and EEG in infant research. It will give an overview of technical considerations when putting together a co-registration lab and when setting-up the hardware. To facilitate later analyses, some precautions must be taken when programming co-registration experiments, which will be outlined. Furthermore, particularly in research with young infants, timing of the EEG-preparation and the eye-tracking calibration plays a crucial role, as infants are only alert and awake for a limited time. Tips will be provided on how to prepare both the eye-tracking and EEG systems as efficiently as possible, to make the best use of the time the infant is awake. The workshop will combine technical background information with examples from the lab to help getting started with combined eye-tracking and EEG.
4 January 2017, 10:15-11:45
Fee: EUR 20
Analyzing co-registered eye-tracking and EEG data
Co-registered EEG and eye-tracking data can provide abundant information, for example regarding fixation locations, pupil size, fixation-related neural potentials, saccade-related responses and underlying sources. However, results from the combination of both methods are tricky to analyze, as both measures need to be aligned first. Furthermore, eye-movements create large artefacts in the EEG signal, covering up neural responses. Compared to research with adults, infant data is even more challenging to analyze due to lower trial numbers and noise. In the first part, this workshop will discuss considerations during the analysis procedure. Particular caution must be taken when selecting filter settings for co-registered data. Different tools can be used to correct eye-artefacts; Independent Component Analysis (ICA) will be discussed as one possible option. Furthermore, information from eye-tracking data can be used to identify noisy samples in the EEG data. Once the data has been preprocessed, different measures can be extracted, including Event-Related Potentials (ERPs) occurring before saccade onset, fixation-related potentials and saccade-related potentials, which will be outlined in the second part of the workshop. Co-registration research with infants is still rare; however, the basic findings regarding these measures so far will be reviewed in the third part of the workshop to provide an overview of the responses previously identified in infants. In the end there will be time for specific questions regarding the analysis and available software solutions. In summary, the workshop will provide a basic introduction to analyzing co-registered eye-tracking and EEG data.