Eye-Tracking with Python and Pylink

Preface 5Chapter 1 A gentle introduction to Python 7Install Python 7Python modules 8Python shell 9Script editors 11Data types 12Numbers 12Strings 12List 14Tuple 15Sets 16Dictionary 16Booleans 17Operators 17Data type conversion 18Control flow 19if statement 19for statement 20while statement 21More on looping 22List comprehension 22Functions 23Output 25Output formatting 25Files 26Modules 28Choose a library to create your "video games" 29Where to go from here 29Chapter 2 Building experiments with PsychoPy 31Install PsychoPy 31PsychoPy Coder 321Open a window 34Screen units 34Monitor 36Window types 37Gamma 37Vertical blanking 38Call on flip 39Screen capture 39Visual stimuli 40Shapes 40GratingStim 42TextStim 43Font and font files 44Right-to-left text 44Wrap width 45Non-ASCII characters 45Aperture 45Mouse and keyboard 47Mouse 47Keyboard 48Register keyboard events with the event module 49Register keyboard events with the ioHub module 49Register keyboard events with PsychHID 50Trial control 51A real example: Simon effect 54Chapter 3 Building experiments with Pygame 59Install Pygame 60Display 61Events 63Draw 65Text 66Image and sound 68A real example: Posner cueing task 69Chapter 4 Getting to know Pylink 76A brief introduction to eye-tracking 76Install Pylink 78An overview of an eye-tracking experiment 78Connect to the tracker 80Open a camera setup / calibration screen 812Configure the tracker 81Open an EDF file 82Calibration 82Data recording 82Retrieve the EDF data file 83Disconnect from the tracker 83A real example: Free viewing 83Calibration graphics 86Idle mode 86EyeLink Host commands 86Preamble text in EDF 87Record status message 87Drift-check/drift-correction 87Logging messages 88Chapter 5 Preparing scripts for analysis and visualization in Data Viewer 90Trial segmentation 91Trial variables 93Interest Areas 95Background graphics 97Size of the screen 97Image 97Video 98Simple drawing 99Draw list file 101Target position 102Examples in PsychoPy 102The Stroop task 102Custom graphics for calibration 106The DISPLAY_COORDS message 107The TRIALID and TRIAL_RESULT messages 107Record status message 107Background graphics: the IMGLOAD message 107Trial variables messages 107Messages marking critical trial events 108Video playback 108Pursuit task 113Chapter 6 Retrieving gaze data over the link 119Samples and events 119Retrieving sample data 1213Commands for sample retrieval 121Example in PsychoPy: Gaze-contingent window 124Retrieving eye events 127Commands for event retrieval 127Example in PsychoPy: Fixation trigger 133Recording playback 136Chapter 7 Advanced Pylink Functions 141Drawing to the Host PC 141Option 1: Using the draw commands 141Option 2: Sending images to the Host 142Option 3: The bitmapBackdrop command 143Send TTL via the Host PC 145Broadcasting 148Calibration and custom CoreGraphics 151Chapter 8 Data analysis and visualization in Python 163EyeLink EDF data file 163Samples 163Events 164Other useful information in the EDF data file 165EDF2ASC Converter 166Extract data from the ASC files 169Parse the ASC file with the string function split() 169Parse ASC files with regular expressions 174Data visualization 176Gaze trace plots 177Heat maps 180Scan path 183Interest area-based visualization 183Chapter 9 Miscellaneous 185Predefined constants in Pylink 185Frequently used EyeLink Host commands 185References 187