1. Instructions • In the following eight trials you will see a cross presented, briefly, at the center of the screen. • One of the arms (horizontal or vertical) is longer than the other. For example: Vertical Arm is Longer Horizontal Arm is Longer

2. Instructions • Your task is to focus on the cross and decide which arm (horizontal or vertical) is longer. • The display is preceded by a fixation display that contains a plus sign. This is to focus your attention. • The cross display is presented quickly (0.2 second) • The cross display is followed by a “mask.” + Fixation Cross Display Mask

3. Trial 1: Press SPACEBAR when told

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7. Trial 1: Which arm was longer? • Circle horizontal or vertical on your response sheet

8. Trial 2: Press SPACEBAR when told

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12. Trial 2: Which arm was longer? • Circle horizontal or vertical on your response sheet

13. Trial 3: Press SPACEBAR when told

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17. Trial 3: Which arm was longer? • Circle horizontal or vertical on your response sheet

18. Trial 4: Press SPACEBAR when told

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22. Trial 4: Which arm was longer? • Circle horizontal or vertical on your response sheet

23. Trial 4: Did you notice anything else that you did not notice on the preceding three trials? • Write yes or no on your response sheet • Label this answer as “Trial 4a”

24. Trial 4: If you answered yes, what did you see? • Select one of the following shapes and write the corresponding number on the response sheet. • Label this answer as Trial 4b: 1 2 3 4 5 6

25. Trial 4: If you answered yes, in which quadrant you see the item? • Select one quadrant and write the corresponding number on the response sheet. • Label this answer as Trial 4c: 1 2 4 3

26. Trial 5: Press SPACEBAR when told

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30. Trial 5: Which arm was longer? • Circle horizontal or vertical on your response sheet

31. Trial 6: Press SPACEBAR when told

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35. Trial 6: Which arm was longer? • Circle horizontal or vertical on your response sheet

36. Trial 7: Press SPACEBAR when told

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40. Trial 7: Which arm was longer? • Circle horizontal or vertical on your response sheet

41. Trial 7: Did you notice anything other than the cross? • Write yes or no on your response sheet • Label this answer as “Trial 7a”

42. Trial 7: If you answered yes, what did you see? • Select one of the following shapes and write the corresponding number on the response sheet. • Label this answer as Trial 7b: 1 2 3 4 5 6

43. Trial 7: If you answered yes, in which quadrant you see the item? • Select one quadrant and write the corresponding number on the response sheet. • Label this answer as Trial 7c: 1 2 4 3

44. Trial 8: On this trial, do not do the line judgment task. Just watch the whole display. Press SPACEBAR when told

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48. Trial 8: Did you notice anything other than the cross? • Write yes or no on your response sheet • Label this answer as “Trial 8a”

49. Trial 8: If you answered yes, what did you see? • Select one of the following shapes and write the corresponding number on the response sheet. • Label this answer as Trial 8b: 1 2 3 4 5 6

50. Trial 8: If you answered yes, in which quadrant you see the item? • Select one quadrant and write the corresponding number on the response sheet. • Label this answer as Trial 8c: 1 2 4 3