Feel free to download Psykinematix GPU v2.2 (September 2017 - 'Back To School' Release). It comes as a trial version you can fully evaluate for 15 days after which it turns into a demo version you can still use to enhance your teaching of visual perception & psychophysics ! This demo version can be fully re-activated on purchase on a Researcher license .

Download Psykinematix GPU 2.2 [163MB]
(compatible with OSX 10.6 "Snow Leopard" to 10.13 "High Sierra")

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Other Editions:   Student Edition v1.7  |  Standard Edition v1.7   Compare All Editions

System Requirements

Minimum:Mac OS X 10.6, Intel Core, 256MB VRAM
Better:Mac OS X 10.8.5, Intel Core Duo 2Ghz, 512MB VRAM, or better
Recommended :macOS 10.13 (High Sierra), 2.4Ghz Intel Core i7, 1GB VRAM, or better

Release Notes

GPU Edition Version 2.2                                              Released: September 25, 2017

Full Compatibility with macOS 10.13 "High Sierra"

GPU Edition Version 2.1                                               Released: June 21, 2017

New Features:

  • On-the-fly movie export of whole experimental session when control-clicking the "Start" button,
  • Support for Interlaced Stereo mode,
  • Support for time-varying position of whole RDK stimuli,
  • Support for dynamic shape in shape-based RDK stimuli,
  • "Custom" placement of stimuli instances in spatial nAFC Procedure (through [NFCINDEX] variable),
  • Addition of Parameter Configurations (independent variables) in Experiment Control Settings,
  • Notification system to warn about potential issues affecting the experimental setup (e.g. brightness change, expired calibrations, etc.)

Feature Improvements:

  • Improved compatibility with macOS 10.10 "Yosemite" to 10.12 "Sierra",
  • More reliable movie Export of OpenGL preview,
  • Addition of Anti-aliasing options in Experiment properties,
  • Support for chromatic coordinates specification using a chromatic diagram (for xyY and Yu'v' color spaces),
  • Support for trichomatic specification of background appearance in Experiment Display Settings,
  • Addition of xyY, Yu'v', L*a*b* as "Color Space" in Default Preferences tab,
  • Addition of 'bessj1' and 'bessjn' Bessel functions for Custom stimulus,
  • Support for 'rnd' and 'irand' functions in shader-based Custom Stimuli,
  • Support for 'time' variable directly in custom expression (also works for OpenGL Preview or movie export)
  • Improvement of Graphing Math Palette to specify temporal properties of stimuli,
  • Support for spatial jitter direction in SSS stimuli (x-, y- and isotropic in addition of xy-),
  • Improved generation of non-overlapping heterogeneous SSS stimuli elements with warning in case the overlapping constraint is too strong,
  • Addition of minimum/maximum abort criterion based on a number of consecutive incorrect responses in Staircase properties panel,
  • Support for custom catch values in Staircase properties panel (multiple values separated with \),
  • Support for Standard/Test randomization for MOCS and Bayesian Methods,
  • Addition of a separate ISI parameters to insert between the Standard/Test randomization in Yes/No procedure,
  • Addition of PAUSETRIALS, PAUSETIME, PAUSEDURATION and PAUSEMSG system variables to control pauses at regular intervals
  • Support for string variable in Association composing,
  • Better estimation of calibration completion levels (based on the selected chromatic mode),
  • Addition of NetStation Drift Correction and Sync Timing options to troubleshoot communication timing,

User interface improvements:

  • Events' property panel can now be opened by simply clicking the events' icon,
  • Psykinematix files can be opened by directly double-clicking them in the Finder (*.epkmx, *.lpkmx, *.dpkmx),
  • Support for undo/redo operations in Designer panel,
  • Addition of a contextual menu to events in Designer panel
  • Support for undo/redo operations when editing expression for "Custom" stimuli,
  • Detect and emit descriptive error when image RSVP is set with "All Simultaneous" selection mode,
  • Redesign of Plotter panel,
  • Subject-specific parameter/values can be added, deleted or edited directly in Subject panel,
  • Ability to select which data to show in the Gamma calibration table drawer (& addition of CIE xy and DE2000 data),
  • A particular resolution and all its calibration configurations can now be deleted by control-clicking the '-' button in Calibration panel,
  • Addition of an option for alternative ESCape key as a work-around to missing ESC key on newer MacBook &MacBookPro laptops with Touch Bar),


  • Detect change of subject selection through up/down arrow keys and update variable table in Subject panel
  • Stuck textfields when locking the properties panels,
  • Blank texture generation for non-precomputed images with random duration,
  • Issue with same name events embedded in a timeline,
  • Issue with global rotation in text or image-based MEF,
  • Issue with expression-based evaluation of x,y coordinates of SSS stimuli,
  • Uncorrect link for Psykinematix Facebook Group from Help panel,
  • Blank color stimuli when LMS to RGB matrix gets reset,
  • Issue with lost editing being when closing the math palette,
  • Shader-based stimulus generation when using the nAFC Procedure.
GPU Edition Version 2.0.2  Released: Sept 20th, 2016

Full Compatibility with Mac OS X 10.12 (Sierra)

Version 2.0.1 (Researcher/GPU Edition)  Released: Jan 7th, 2016

Full Compatibility with Mac OS X 10.11 (El Capitan)

Version 2.0 (Researcher->GPU Edition)  Released: July 28, 2015

New Features:

  • Support for GPU-based preview and run-time rendering for custom, grating and checkerboard stimuli,
  • Option for GPU-based stimulus generation in Timing Preferences, Experiment Display Preferences and Rendering Control Settings for individual stimuli,
  • Backup & Restore options in File menu,
  • "Open Log File" option in File menu,
  • Support for multimedia image stimulus in MEF and SSS stimuli,
  • Support for Conditional event embedded in Association event,
  • Standard/Test intervals randomization option in Yes/No procedure,
  • pnoise(X,Y) function to generate Perlin noise in Custom Stimuli,
  • log2(), clip(), step() and hsmoothstep() in mathematical expressions,
  • Support for 11.6 bits monochromatic mode through Bit-Stealing
  • Support for Noisy-Bit technique (stochastic dithering) to provide quasi-continuous luminance resolution (based on Allard & Faubert 2008)

Feature Improvements:

  • Better report in Plotter panel of results obtained from interleaved methods,
  • Support for expression-based "ResponseTime" property in "Trial Properties" inside Procedure panel,
  • Support for time-varying alpha for Text Multimedia stimuli,
  • Support for custom image as target and square shape for ground in Ishihara stimuli,
  • Addition of "Targeted Chromatic Mode" in Gamma calibration panel,
  • Report R2 value for Gamma correction,
  • Support for time-varying grid size in MEF stimuli,
  • Support for Catch trial proportion in Staircase method,
  • No error anymore for missing event in Association Composed Stimuli,
  • Addition of a "Hole Size" parameter in zone specification for RDK stimuli,
  • Addition of "Asyn/Syn" lifetime mode in RDK stimuli,
  • Support for time-varying elements in RDK stimuli and "Asyn/Syn" dynamics mode,
  • Support for time-varying direction, speed, coherence and dot number in RDK stimuli,
  • Report multiple declarations of the same variable as a warning rather than a critical error,
  • Better randomization of conditions with different number of trials,
  • Addition of optional Pause between repeats in Conditions Method,
  • Addition of [RESPONSE] and [RT] system-defined variables,
  • Support for comparison (<a>==<b>) and conditional (<a>?<b>:<c>) formats in trigger information,

User interface improvements:

  • Prevent attempt to change event title if locked,
  • Experiment title can be renamed for individual sessions in Subjects panel,
  • Access to all sections of documentation from contextual Help window,


  • License activation issue under OSX 10.7 and 10.8,
  • Issues with time-varying texture-based stimuli used as RDK elements,
  • Crash when using custom stimuli with RGB outputs,
  • Improved speed and memory usage when generating time-varying stimuli by preventing computation of duplicated frames,
  • Hang problem when closing some Keyspan serial devices,
  • Shape stimuli not rendered in achromatic mode when selected,
  • Preview in window mode always rendered in RGB mode.


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