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MRI eye tracker

The MRI eye tracker is an SMI system comparable to that in the MEG, except for some additional shielding and the fact that it needs to look at the eye through a special mirror in the custom mirror box used for eye tracking. The radiographers know how to set up the hardware and get a good picture of the eye. Once this is done, the system works normally.

There is a dedicated PC in the scanner control room for eye tracking using i View X software. The serial port connection, necessary for use with E-Prime, is current setup with Stim3 but can be switched over to another machine if you ask nicely. The SMI calibration is run from the same machine where your experiment runs by using WinCal, a little application which can present the calibration targets on the stimulus computer. Read more about the calibration procedure using WinCal in the section EyeTrackingWithEprime.

Eye tracking is often difficult with the MRI-compatible goggles. If volunteers can wear contact lenses instead this tends to work better. Tracking can also be difficult if the participant is wearing any eye makeup, so all eye makeup should be removed prior to scanning.