La Technologie des
Mouvements Oculaires en
Linguistique Expérimentale
Rachel Shen
The key points of this
presentation
What is eye tracking?
Eye tracking in language studies and some examples;
A very brief evaluation of different types of eye trackers;
The SMI eye tracking glasses
What is eye tracking?
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Subconscious movements of the eyes
during visual activities, such as scene
viewing, reading, etc.;
Intake of information through those
movements will be processed by
human brain;
The eye-mind assumption and the lag
between attention and fixations;
Track them!
Eye tracking in Language
studies: READING
Self-paced reading;
Gaze contingency
paradigm;
Linguistic manipulations
can be reflected in the
measurements of
“fixation time” and
“saccade time and
direction”
From a study of speed reading made by Humanist laboratoriet,
Lund University, in 2005. Data are recorded using an SMI iView X
240 Hz video-based pupil-corneal reflex eye tracker.
Reading example: Normal sentence
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Reading example: Syntactic anomaly
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Reading example: Semantic anomaly
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Eye tracking in Language
studies: Visual World Paradigm
(VWP)
Auditory input and visual input;
Eye movements (most commonly, no. of fixations and
saccades) on the visual input are recorded;
Sensitive to various linguistic properties from word
recognition to syntactic ambiguity resolution (and beyond)
VWP: the Advantages Compared to
Reading
Provides clues about what happens prior to a critical
word or region (can measure attention);
Measures relative direct interpretations of a listener,
which might be misjudged by the listener himself;
Some phenomena can only be measured in situated
condition;
Easier to apply with children and patients
Example VWP: Donald Duck and
tractor (Conklin, Dijkstra & van
Heuven, 2008)
HE
200-2000ms
200-400ms
Example VWP: Cue integration during
spoken word recognition (Toscano &
McMurray (2012)
VOT (400ms)
vs. VL (700ms)
VOT time course
Eye tracking in Language
studies: Production
No spoken input;
To name an object or describe a scene;
Gaze movements and object viewing order are
recorded, especially relative to the speech
output;
Reflects utterance planning
Example Production (Gleitman,
January, Nappa & Trueswell, 2007)
Onset of each stimuli
were given to manipulate
the attention;
Fixation order is affected
by the manipulation;
Word order choice for
utterance production is
affected;
The integrated paradigms
Situation specific;
Pragmatic inferencing;
Dialogue
Dialogue
The map task (Anderson et al., 1991);
Tree decoration task (Ito and Speer, 2006);
Tangram task (Clark and Wilkes-Gibbs, 1986);
Lego task (Clark and Krych, 2003);
Baufix ( Poncin & Rieser (2006);
Cooking (Hanna & Tanenhaus, 2004)
Example Situated: cue encoding
and decoding (Snedeker &
Trueswell (2003))
Tap the frog with the flower. (Ambiguous)
Tap the frog by using the flower.
(Unambiguous)
Tap the frog that has the flower.
(Unambiguous)
Eye tracking Data presentation
Animated;
Static saccade path;
Heat maps;
Blind zone maps
Canadian viewers
US viewers
Which eye tracker?
• Setups vary;
• Sample rates vary (30Hz-2000Hz);
• Bright pupil (varying light conditions) and dark pupil
tracking (Lab condition);
• For detailed comparison:
http://www.eyetracking.com/Hardware/Eye-Tracker-List
The SMI Eye tracking
• Glasses
System Type: Video based glasses-type eye tracker
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Sampling Rate: 60Hz binocular
• Method: Dark pupil, pupil-cr
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Binocular Tracking: Yes (auto parallax correct)
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Accuracy: 0.5 degrees over all distances
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Gaze tracking range: 80° horizontal, 60° vertical
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Additional Details: HD Scene Camera Resolution:
1280x960
The workflow of the SMI
Eye tracking Glasses
Design
Record
Analyse
The SMI Eye tracking
Glasses Example
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Field work with the SMI
Eye tracking Glasses
• Easy to carry (1300g /246g);
• Easy to setup;
• Easy to calibrate and validate with live feedback
on scene video;
• Long recording time (2-4hrs);
Data view and analyses with
the SMI Eye tracking
Glasses
• Event replay such as gaze size, scanpath, etc.;
• Raw data of fixations and saccades in terms of
location, start time and end time, etc.
Please come and try it!
Merci beaucoup pour votre temps!