Institute for Language Sciences Labs


Flanker Task


  • Boilerplate experiment (default)
  • Author(s): Chris van Run
  • Download link
  • Modules:


The target is flanked by non-target stimuli which correspond either to the same directional response as the target (congruent flankers), to the opposite response (incongruent flankers), or to neither (neutral flankers). The test can be used to assess the ability to suppress responses that are inappropriate in a particular context.

Randomisation is according to these rules:

  1. No more than 3 consecutive sides (direction).
  2. No more than 2 consecutive flanker (congruency).
  3. Never two consecutive trials that have the same congruency AND side.

Example screenshot from the task.


Installation instructions

To run the experiment you need the Zep experiment control application. At the ILS Labs this is already installed on all systems. To install Zep at home or on your personal laptop go to this link and follow instructions there.

To install this experiment:

  1. Download the experiment from this link.
  2. Extract the .zip-file into a target folder (any location will do).
  3. This will produce an experiment folder under the target folder.
  4. Read the readme that comes with the experiment.
  5. Open the console application (under Windows click windows-terminal.bat, under Linux click and type the following command:zep flanker_task
    In this command flanker_task represents the name of the experiment you wish to run.


This experiment script comes with absolutely no warranty. It is your responsibility to pilot test the script and analyze the results before using the script for your research. Be sure to know what the adjustable parameters of the script mean and check whether the script presents stimuli and records responses exactly as you want it to. If necessary, ask the author of the script to explain the things you do not yet understand.