1. Introduction Processing Verbal Information in Concept Maps How people read concept maps in the context of a semantically meaningful task?

2. Eye tracking How do we see? Fixations – visual gaze on a single location; 200-350 ms Saccades – fast movement of the eye Constant state of vibration at a rate of 30-70 Hz

3. Eye tracking How does it work? Infrared light source to illuminate the eye Sensor to capture a reflection of the user’s eye Calculating the gaze

4. Eye tracking Tobii T120 Data rate120Hz Accuracy0.5 degrees Drift0.1 degrees Head movement box30 X 22 cm at 70 cm Blink tracking recoverymax 8 ms

5. Eye tracking Tobii DataMeasure Pupil sizeCognitive Load Fixations/ObservationsCognitive processing/Attention Gaze Pattern (sequence) Self-regulation

6. Eye tracking Data output Timestamp - in milliseconds GazePointXRight - horizontal screen position of gaze Event – automatic and logged mouse clicks and keys Data1 – Data field for the event

7. Example of Input

8. Area of Interest - AOI

9. Eye tracking Replay

10. Eye tracking Data output/AOI Fixation length - in milliseconds Fixations – number in AOI Total time – in AOI in milliseconds Time to first fixation – in milliseconds

11. Eye tracking Visualizations

12. Eye tracking Visualizations

13. Eye tracking Visualizations

14. Eye tracking Logged data

15. Experimental Design Concept Maps

16. Task

17. Strings

18. Transition Matrix

19. Map A

20. Look “next”  Connected  Go to node with arrowheads  Go to node with reverse arrowheads  Distance  Size of node

21. Concept Map “Model”

22. Assume:  Every sequence starts at N  Track each sequence until Terminal Event  Keep track of whether it was a First Visit or a Return Visit

23. Concept Map “Model” Assume:  Every sequence starts at N  Track each sequence until Terminal Event  Keep track of whether it was a First Visit or a Return Visit

24. Concept Map “Model” Forward FixationNLF Backwards FixationNCB Incomplete FFNL Incomplete BFNC Immediate Retrospection (Node)NXN IR (Link)NYN IR (Incomplete FF)NLN IR (Incomplete BF)NCN Delayed IRFNLFN or NLFN Delayed IRBNCBN or NCBCN