Template: Different Instructions at the Beginning of Each Block
Different Instructions at the Beginning of Each Block

Required Experiment Builder Version: 1.5.58 or higher
EyeLink Required: Yes
Type: Complete Example
Difficulty Level: Easy to Intermediate

This example illustrates:
  • How to use of multiple Conditional nodes to determine the type of the each block
  • How to collect button response information (button press, RT calculation, and response accuracy)
  • How to use Sound nodes to play different audio feedback for correct and incorrect trial performance
  • How to use Send EyeLink Message node to mark the participant's performance in Data Viewer

This experiment illustrates how to present different instructions to the participant at the beginning of each block of the experiment. It uses a series of conditionals to make a decision about which instructions to present based on which block it is. The first block is a practice block consisting of six trials. The next two blocks each consist of twelve trials. The instructions of each block are different.

Furthermore, it illustrates an experiment involving the presentation of a series of different images in the periphery while the participant maintains gaze at a common fixation point in the center of each presentation screen. A trial proceeds as follows: A fixation point is presented in the center the screen. When the participant achieves a steady gaze on the fixation point they presses a button on the control pad to start the trial (If the gaze is not directed at the fixation point the trial will not start). The fixation point is present throughout the trial. While the point is present a cue (consisting of a picture of a face) first appears on either the left or right side of the screen for 300 msec. Then the cue disappears leaving just the fixation point for 200 msec. The fixation point then increases in size for 200 msec and returns to its original size for an additional 200 msec. Finally a target rectangle appears on either the left or the right side of the screen. The participant is expected to press one of two buttons to indicate the location of the target. One of two sounds then informs the participant of whether or not the response was accurate. If the participant does not react to the target within 1000 msec then the trial times out.

**Additional detailed information about the project is given in the notes section for most nodes. To see notes for a given node, either mouse over that node or click on it to display the notes window. If the notes window is not visible, go to the "View" drop down menu in Experiment Builder, select "Properties", and check "Note".

NOTE: Please see our Performing Different Types of Trials In the Same Experiment in Experiment Builder Webinar for more details.

  • Download the Different_Instructions_at_the_Beginning_of_Each_Block.ebz example from this message.
  • Launch the Experiment Builder application.
  • Unpack the Different_Instructions_at_the_Beginning_of_Each_Block.ebz file to a location on your Experiment Builder PC with "File menu -> Unpack".
  • Open the project in Experiment Builder.
  • Deploy the project to a new folder.
  • Run the Different_Instructions_at_the_Beginning_of_Each_Block.exe from the deployed directory.

.ebz   Different_Instructions_at_the_Beginning_of_Each_Block.ebz (Size: 189.2 KB / Downloads: 124)