Update History


  • Bug fixes
  • Edits to documentation


  • All reference documentation (core and element types) is now online. Non-reference documentation remains in /docs but is also available online.
  • Revamp of MATLAB help: All documentation is now hyperlinked, including all function help text, Contents.m files summarizing files and folders, all options in pb_prefs, and the pb command menu. Added files summaries for /tools and /element type programming/basic. Now uses the standard MATLAB ver command for version information.
  • Added compatibility options which are especially useful to avoid problems that Psychtoolbox experiences on Macs. See pb_prefs → screen tab → sync tests and compositor.
  • Save and resume any experiment run quit part-way through (type help runExperiment for details)
  • Any property that uses deg visual angle can also use px, wh (window height), ww (window width), or cm units using <cd>{value, <cd><cds>"unit"<cds><cd>}<cd> syntax
  • All visual element types now have all core visual options (rotation, opacity, convolution filter, etc.). (Previously some did not implement these options, e.g. line, linearDotMask, etc.)
  • Added intensity scaling as a core visual option
  • New input options to element_draw, _redraw for element type programmers
  • Minor additions/changes: soundRecorder elements save sound recorded so far if experiments halts. Optionally use one number for symmetric dimensions in size properties across many element types (e.g. one number for a square side length as opposed to a rectangle). Added fit/fill/px sizing and crop options to element types picture and movie. Can set Gaussian convolution filter width. Can specify separable custom convolution kernels. And more.
  • Bug fixes
  • Edits to documentation


  • Graphical interface for setting general preferences (default property values for trial, experiment, and device objects) using command pb_prefs. Especially useful for easily setting common parameters like Psychtoolbox sync tests; experiment window size; sound device, sample rate, and quality; etc.
  • Results output is now organized by object, not object class. More readable and each trial always uses one row.
  • Second results output now uses nan and <missing> values where possible to preserve numeric and string arrays for easier analysis
  • Option to set trial repetition and order directly in trial definitions using trial object property n. An alternative to the command setTrialList for unusual cases.
  • Added tools randomDistribute, randomDistributePerms for use in experiment scripts. Added an output to randomOrder to facilitating inverting order.
  • Added element type dotPath: arbitrary dot motion based on (x, y) time series data
  • Minor tweaks: Default volume = on for movie elements
  • Bug fixes
  • Edits to documentation


  • Sound input functionality using Psychtoolbox PortAudio, and element type soundRecorder to record sound to file
  • A sound-based Stroop demo where the subject responds verbally
  • Minor additions/changes: Set a break interval in a repeating display for element type bmlWalker
  • Edits to documentation


  • Added support for Cedrus response pads, and element type cedrusPress
  • Streamlined framework for devices (screen, PortAudio, keyboard queues, ports, button boxes, etc.) in element type code
  • Reduced start latency of keyPress, portSender, portReceiver, and other elements that use keyboard queues or ports
  • Bug fixes
  • Edits to documentation


  • All response handler elements can now register triggers as well as record responses from subject, allowing you to use any response handler modality for triggers
  • Element type keyPress now uses a keyboard queue by default for better time measurement precision and never missing a key press. Polling functionality (Psychtoolbox KbCheck) is still available as an option.
  • Merged element type keyReceiver into keyPress
  • Add latency and buffer size properties to speaker device objects, which allows control over those technical settings in Psychtoolbox PortAudio. This is necessary to prevent crackling on some systems.
  • Added multisampling (general antialiasing) option to screen device objects
  • Bug fixes
  • Edits to documentation


  • Added a second results output from runExperiment which contains results compressed into a numeric matrix or other arrays for extracting/plotting/analyzing with MATLAB functions. The first results output remains easily viewable as a table in MATLAB's visual variable editor.
  • Added an option in addTrial to define distinct trial groups by number, which can be useful in complex experiments
  • Added Stroop and biological motion demo experiments
  • Bug fixes


  • Added element type fixationGrid. This shows a grid of concentric circles and diagonal lines, per Tyler, C.W. et al. (2005).
  • Edits to documentation


  • Simplified the interface for setting timing from sync with a scanner or other external device
  • Minor additions/changes: Fast step sizes now default to regular step sizes for fixed step staircases
  • Bug fixes


  • Can now use any static visual elements in pre-trial intervals, not just fixation crosses
  • Edits to documentation


  • Minor additions/changes: Can now load motion data directly from files for bmlWalker elements. Faster opening of bmlWalker elements when many there are many elements using the same motion data in an experiment


  • PsychBench 1 beta released