The Attention Network Test (ANT) was developed by Jin Fan and Michael Posner. More information about it can be obtained from Fan's website.

In 2009, we published an article introducing the ANT to researchers and clinicians with an interest in driving. At that time, we were using the Java version of the ANT, downloaded free of charge from Fan's website. But it takes approximately 20 minutes to complete, which is too long for our purposes. Therefore, we developed a shorter version of the ANT, called the CRSD-ANT. It was programmed by Luke Docksteader and Kris Scott, and takes about 10 minutes to complete. We are currently working on an article that reports very strong correlations between measures from the CRSD-ANT and Fan & Posner's Java ANT. Anyone interested in trying the CRSD-ANT can download it (free of charge) below.

This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-sa/3.0/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California 94105, USA.

Any original or modified version of this software must attribute the original work to the following (original) authors, and include a hyperlink (or at very least a URL reference) to their respective Web sites:

• Luke Docksteader - http://docksteaderluke.com
• Kris Scott - http://krssctt.com

Click on the "Zip" link in the sidebar above or simply click here.

Extract the archive using the zip utility of your choice. Once the archive has been extracted a new folder named "CRSD-ANT" should now exist.

Inside of the newly created "CRSD-ANT" folder there should be a file named "index.html". Open this file with the Firefox Web browser and follow the on-screen instructions.

You can use a URL query to pre-populate some of the fields (ID, Session Number, Study ID, Group ID, and Age). This is done in the following format, where 'x' indicates a value:

index.html?ID=x&sessionNumber=x&studyID=x&groupID=x&age=x

The index.html page will extract the values if they are present and pre-populate the main.html page with those values, marking the text boxes as read-only. If one or more values are not present in the URL query, then the text boxes will will not be pre-populated and will be editable.

Important Note: The CRSD-ANT program will run in any browser, but timing accuracy is not guaranteed in all browsers, and importantly, it is known to be faulty in Internet Explorer. If you do not have Firefox, you can download it here.

Under default operation, the left and right arrow keys are used. If you wish to change these (for example, changing them to E and I) you will need to do the following.

1. open trial.js
2. under the stage4Interrupted function, locate and change the following key values:

• Left key:

if (e.keyCode == 37) {

• Right key:

if (e.keyCode == 39) {

• Change these values to the desired key values.

3. Either update the main.html page instructions to reflect these changes, or advise the participant of the change in keys.

1. Find image with an aspect ratio of 1:1, preferably 100x100 pixels. Images must be of type .png to allow for transparency.
2. Create a second version of the image facing the opposite direction.
3. Place both images in the images/targets folder and rename them to "NAMELeft.png" and "NAMERight.png". For example: a horse picture would become "HorseLeft.png" and "HorseRight.png".
4. Add a reference to the image file on line 1 of the config/targetTypes.js file:

var stimList = ["Arrow", "Truck", "Hand", "Airplane", "Car", "Horse"];

1. Open js/navigation.js in the text editor of your choice.
2. Near the top of the file, change the following line, replacing "4" with the desired number of blocks:

var numberOfTestBlocks = 4;

Description of Data Files Saved by the CRSD-ANT.

[1] Note: For all summary statistics that are computed based on response times, only correct responses with RTs between 100 and 1500 ms are used. RT < 100 ms is considered anticipatory, and so is excluded; and the maximum display duration for the target is 1500 ms, so that is also the maximum possible RT.

[2] A trial is considered correct if the subject correctly indicated the direction of the target arrow, and if the RT was within the range 100 to 1500 ms.

[3] Set variable CORRECT to 1 if the subject’s response matches the correct response, and if the RT is in the range 100 to 1500 ms. Otherwise, CORRECT = 0.