The tutorial has been broken up into step, these are as follows:

Transcription

1 The tutorial will show you how to create an IGT experiment using Opensesame. It will introduce you to some of the items that are available to use, and it does involve programming but not much. The tutorial has been broken up into step, these are as follows: Step 1: The experiment design, what is required? Step 2: Create a new experiment. Step 3: Add items Step 4: Rename the items Step 5: Add instruction and thank you text Step 6: Setup loop Step 7: Setup keyboard Step 8: Setup sketchpads Step 9: Setup feedback Step 10: Setup inline scripts Step 11: Setup logger Save the task at the end of each step. Step 1: The experiment design, what is required? Iowa Gambling Task, what is required? We will need two images, one of the back of a card and the other a slightly darker version to indicate that the card has been selected. Instructions on screen? For this tutorial yes. How many presentations of the stimuli are there? In this tutorial we are just going to run through the it 10 times.. How many stimuli are there? Each presentation is made up of four cards. What is the participant required to do, how do they interact with the task? They have to press 1,2,3,or 4 to select the required deck Do we want to provide feedback? Yes, they will need to see how much they have won or lost, and the selected deck is indicated. So to make it simple we will use four feedbacks. What data do we want to save? What deck was selected, wins and losses. End screen? Yes, just to say thank you Anything else. Need to keep a running total of wins and losses, so will have to use an inline script to define variables and another to calculate running totals. Each of the answers above relates to an item from the toolbar. 1 text display (instructions) 1 inline (to define variables) 1 loop with sequence (why sequence? As there is more than one item to loop) 1 sketchpads 1 keyboard response 1 inline (to update winnings etc) 1 sketchpads 1 logger 1 text display (end screen) Step 2: Create a new experiment. Open Opensesame, in New (Tab area) double click on Default template.

2 Change the description(tab area) from New experiment to IGT. Whilst on the General Properties tab, change the resolution to match your screen resolution. Leave everything else as it is. Let s tidy up the new experiment, in overview there are two items that are not required; these are directly below experiment. To remove any item, right click on an item and select delete from the menu. When you delete an item, it goes into the Unused items, which means that the item is still available for use in this experiment and as a consequence adds to the file size. If you do not intend to use again then click on Unused Items and then click on Permanently delete unused items. Do this for the two items already in there. Step 3: Add items Now you are going to add the required items to the experiment, in the order listed at the end of step 1. There are two ways to add new items to the experiment, one is to drag the required item from the Toolbar to the required place in the Overview, if the item is visible in the Overview then click on the double arrow at the bottom of the Toolbar. The other way is to click on the sequence in overview, where the item is needed and use the Append new item, selected the required item from the drop box and click on the plus button. If the item is in the wrong location place the mouse

3 cursor over the four little squares to the left of the item, left click and drag the item to its new location. Now, using one of the methods describe above add: 1: text display to experiment 2: inline to experiment 3: loop to experiment; this will bring up a dialog asking if you want to create a loop with a new or existing item. The requirement is to run multiple items in a loop so a sequence is needed. Make sure that sequence is shown and click on create. This will add a loop and a sequence to the Overview. 4: sketchpad to the sequence 5: keyboard response to the sequence 6: inline to the sequence 7: feedback x 4 to the sequence 8: logger to the sequence 9: text display to experiment Step 4: Rename the items Rename the items so that they are meaningful. This can be achieved by right clicking the required item in overview and selecting Rename or by selecting the item in overview and then changing the name in the Tab area.

4 Step 5: Add instruction and thank you text Add the text messages to text_display. In overview click on the required text_display, in the Tab area change the font size to 24 and add the text into the Text window. Leave all other settings as they are. Step 6: Setup loop What information do we put in the loop? The procedure needs to know what the losses will be for each card on every trial. So add four variables a,b,c, and d using the Add variable button. Note; variable names cannot contain spaces. Order should be random. Change number of cycles to 10.

5 Enter the details shown here. The Step 7: Setup keyboard Add 1;2;3;4 to the allowed responses. Leave Timeout as infinite, as it waits for user s response. Step 8: Setting up the sketch pads. Click on the folder icon at the top of the screen or use the view menu and select, Show file pool. Click on the plus button, and add the two image files.

6 The sketchpad needs to display the current and previous total, with four numbered decks. Set duration to 0 You will need to add 4 deck images to this sketchpad. Click on the image tool, then click on the black screen, the Select file dialog will open, select deck. Next using the text tool add two texts one with Previous Total [currency][previous], the other with Current Total [currency][current]. Now enter the script editor There is only one line with deck.png, copy this line and paste it three times. Now change the coordinates of the images and the text as in the above image. Click on apply and close.

7 Next is adding text to the decks, click on the text tool, change color to black and font size to 60. Make sure that you can see the decks (if not use the scrollbars), click on the decks one after the other, starting on the left, labelling the decks 1,2,3 and 4. If the numbers are not centred, then enter the script editor and change the coordinates of the text to match the respective deck. Open the script editor and copy all the text. Step 9: Setup feedback Open the script editor and paste the text over all the existing text. Change the duration from 0 to Close script edit. Now, below deck 1 add the following text, You won [currency][win] (in green, size 18), and You lost [currency][loss] (in red, size 18). Open the script editor, tidy up the position of the text. The image name will have to be changed from deck.png to deckon.png for one image per feedback, i.e. first image for Feedback1, second image for Feedback2 and so on.

8 Copy all this text, and paste it in all the other feedbacks. Then change the position of the green and red text so that it is below its respective deck. In sequence change the Run ifs for the feedbacks. Note; response is the variable returned by the keyboard item. Step 10: Setup and Maths. Setup Enter the following Lines 1 to 9 define all the variables as global Lines 13 to 20 pre-sets the variables with default values Lines 22 to 24 pre-sets the experiment variables with default values Note; to set or get an experiment variable use exp.set (variable, value) or self,get(variable)

9 Maths This step is used to total up the current winnings and losses, based on the deck selected. Enter the following. Line 2, sets the experiment variable previous to current value Lines 4 5 6, if key 1 pressed then get its losses and winnings ( Lines 7 8 9, if key 2 pressed then get its losses and winnings Lines , if key 3 pressed then get its losses and winnings Lines , if key 4 pressed then get its losses and winnings Line 17, calculate total Lines , update the experiment variables. Step 10: Setup logger Unselect all the tick boxes. You will need to select the tick boxes for the variables current and previous ( source setup), response_keyboard and response_time_keyboard (source keyboard) and win and loss (source maths)

10 That is it. Now you are ready to run. Subject number dialog will appear for testing leave it as it is. Click OK Next you will be asked to choose where to save the data file. On completion of this test the Finished dialog will appear. Click No, if a file is added to the file pool then it will increase the file size of the experiment.