The Psychological
Experiments Laboratory

Hans Irtel



Experiment Demos

Lab Course

Vision Demos


Timing Notes








What is PXLab?

PXLab is a collection of Java classes and applications for running psychological experiments. The PXLab system allows interactive design of a wide range of experiments from all areas of psychological research. It includes a run time control system which runs experiments under highly optimized timing constraints.

PXLab's major features include:

  • Complete procedural control for sessions, blocks, and trials,
  • display composition by combining elementary display objects,
  • timing groups of display objects,
  • more than 100 elementary display objects: text, geometric objects, images, gratings, sound, movies, and many more,
  • conditional display execution,
  • response collection from keyboard, mouse, external devices, and sound channels,
  • precise timing with optimized use of accelerated video memory,
  • automatic time control and report of all timing properties,
  • vertical retrace synchronization with native code library under Windows,
  • color control by CIE chromaticity coordinates using built in gamma correction,
  • all display object properties controlled by experimental parameters,
  • experiments can run as local applications or as HTML-embedded applets using the same design file,
  • same program does data collection in the laboratory and on the internet
  • extensible by implementing new display objects in Java code
  • uses ASCII design files,
  • tools for design file editing, command line experiments, and color calibration,
  • special features for class room demonstrations and laboratory courses.

PXLab is available under an Open Source License. If you are interested in cooperating with the development of PXLab please contact .