EyelinkToolbox

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EyelinkToolbox.

The EyelinkToolbox can be used to ceate eye-movement experiments and control the SR-Research Eyelink(c) gazetrackers (http://www.eyelinkinfo.com/) from within Matlab and Octave.

It is incorporated into the PsychToolbox (http://www.psychtoolbox.org/).

It provides an interface to the Eyelink Gazetracker.

It uses a very similar approach as the PsychToolBox and uses the functions provided by the PsychToolBox for graphics and sound.

How to start using it:

The EyelinkToolbox is a collection of m-files and a Mex file. The EyelinkToolbox core is the mex/dll-file called Eyelink. The EyelinkToolbox uses the same approach as the SCREEN mex/dll function provided in the PsychToolBox. Most of the Eyelink functions that are avaible in C are also available under Matlab. In addition, the EyelinkToolbox provides a number of wrapper functions to simplify creating an eye-tracking program. The main functionality of the EyelinkToolbox is demonstrated in a number of demos. This is probably where you want to start if you are new to the EyelinkToolbox.

To use Eyelink, you must also install the SR-Research runtime libraries, downloadable from the Support Section of their website (see above).

For a complete list of available functions type "Eyelink" in the command window. For an explanation of any particular eyelink function just add a question mark "?" after a command. E.g. for help on the function 'Initialize', try either of these equivalent forms:

Eyelink('Initialize?') Eyelink Initialize?

Contents of the EyelinkToolbox folder:

-Contents.m: this file.

-Changes.m: file that documents changes to the EyelinkToolbox

-EyelinkBasic Eyelink mex files and a collection of m-files that provide the core functionality of the toolbox.

-EyelinkDemos EyelinkShortDemos is the best place to start. Contains relatively simple demos. The SR-Research Demo folder is a slightly more elaborate example. The folder BRMIC contains the original example as shown in the EyelinkToolbox article in BRMIC (Cornelissen, Peters and Palmer 2002). It is obsolete in many ways but left in the toolbox for historic reasons.

-EyelinkOneLiners Handy routines that provide less essential functionality

We welcome any observations, suggestions that may help us improve this toolbox. If any particular function you need is still missing, let us know and we'll try to incorporate it into a next release. In case you decide to add or modify functions yourself, please send us the modified code. If you think you've found a bug, please tell us. It will help greatly if you can supply a minimal-length program that exhibits the bug. If you're interested in the c-source code of this project, it is part of the source code of the PsychToolbox (http://www.psychtoolbox.org/).

**Citing the use of the Eyelink Toolbox**

We would very much appreciate it if you would (also) cite the EyelinkToolbox paper when you have used the toolbox in your work. You could write something like:

We wrote our experiments in Matlab, using the Psychophysics and Eyelink Toolbox extensions (Kleiner 2007; Brainard, 1997; Pelli, 1997; Cornelissen, Peters & Palmer, 2002; see http://psychtoolbox.org).

Kleiner M, Brainard D, Pelli D, 2007, "What's new in Psychtoolbox-3?" Perception 36 ECVP Abstract Supplement.

Brainard, D. H. (1997) The Psychophysics Toolbox, Spatial Vision 10:433-436. Cornelissen, F.W., Peters. E., Palmer, J. (2002).

The Eyelink Toolbox: Eye tracking with MATLAB and the Psychophysics Toolbox. Behavior Research Methods, Instruments & Computers, 34, 613-617.

Pelli, D. G. (1997) The VideoToolbox software for visual psychophysics: Transforming numbers into movies, Spatial Vision 10:437-442. This toolbox is also actively supported and co-developed by SR-Research (http://www.eyelinkinfo.com), the manufacturer of the Eyelink gazetrackers. You can contact them about it. However, if your problem is likely of interest to other users as well, then please post questions on the PsychToolbox mailinglist, which is also monitored by SR-Research.

The EyelinkToolbox and its source code are copyright Enno Peters, Frans Cornelissen and John Palmer. Additional copyrights for some contributed functions are SR-Research and the respective individual developers of those functions.

(Type "Eyelink" or Eyelink('Version') for authors). The toolbox is freely useable and redistributable under the terms of the MIT license. The exact license text is included inside License.txt in the root folder of any Psychtoolbox-3 installation.

Disclaimer: we cannot be hold responsible for any damage that may (appear to) be caused by the use of this toolbox. Use at your own risk!

Frans W. Cornelissen 22nd July 2010 email: f.w.cornelissen@med.umcg.nl

Enno Peters, Frans Cornelissen and John Palmer Groningen, 27-11-2002