User manual

An EyeLink 1000 Tutorial: Running an Experiment

The “Eyedata” template uses link data to display a real-time gaze cursor. The

data is then played back after the trial, drawing the saccade paths and fixation

points to the screen. The bitmap for the trial is a grid of letters.

E. GCWindow

The most useful real-time experiment is a gaze-contingent display, where the

part of the display the subject is looking at is changed, or where the entire

display is modified depending on the location of gaze. These require high

sampling rates and low delay, which the EyeLink 1000 tracker can deliver

through the link.

This template demonstrates how to use the link’s real-time gaze-position data to

display a gaze-contingent window. This is an area centered on the point of gaze

that shows a foreground image, while areas outside the window show the

background image. You supply full-screen sized bitmaps for these, which are

stored in the bmp folder. You can use different images by replacing the one

provided with the experiment with an image of your own with the same name.

F. Control

This template implements a computer interface that is controlled by the

subject’s gaze. The participant can select one of a grid of letters by fixating on it.

The template contains code to support many rectangular selection regions, but

can be simplified if gaze in a single region is all that needs to be detected. The

image for the trial is a grid of letters.

G. Dynamic

This template consists of four experiment blocks. In the first block a red

horizontal moving dot is presented which moves from left to right then back

again repeatedly. The second block presents a red “/” which moves right to left

then changes to “\” when moving left to right repeatedly. The third block

presents white dots at three locations along the horizontal axis. The final fourth

block presents a white dot, a few seconds later another white dot is shown. The

original white dot then fades away.