Now You See It, Now You Don't: Investigating Inattentional Blindness

Working with Human Test Subjects

There are special considerations when designing an experiment involving human subjects. Intel ISEF-affiliated (International Science and Engineering) fairs often require an Informed Consent Form for every participant who is questioned. Consult the rules and regulations of the science fair that you are entering, prior to performing experiments or surveys. Please refer to the Science Buddies documents Projects Involving Human Subjects and Scientific Review Committee for additional important requirements. If you are working with minors, you must get advance permission from the children's parents or guardians (and teachers if you are performing the test while they are in school) to make sure that it is alright for the children to participate in the science fair project. Here are suggested guidelines for obtaining permission for working with minors:

1. Write a clear description of your science fair project, what you are studying, and what you hope to learn. Include how the child will be tested. Include a paragraph where you get a parent's or guardian's, and/or teacher's signature.
2. Print out as many copies as you need for each child you will be surveying.
3. Pass them out to the children or to the teachers of the children to give to the parents. You must have permission for all the children in order to be able to use them as test subjects.

Gathering Permission and Making the Test Video

1. While you wait to get permission to work with your test subjects, start making your test video.
   1. Go to your chosen site with the seven volunteers. They should all have their light- and dark-colored clothing on. Make sure that it is quiet and that there are not a lot of people there.
   2. Have six volunteers all stay within a small area, but one in which they can all move comfortably around, and start passing the basketball around. Once you are filming, the light volunteers in light colors should pass one basketball, and the volunteers dressed in dark colors should pass the other basketball. The volunteers don't need to be too far apart from each other, because they will need to catch the ball during the entire time of filming. You might want to have them all practice a few times before you film the actual clip.
   3. Set up the video camera and tripod. You should place the video camera and tripod such that you can capture all six of the volunteers moving around.
   4. Once you have recorded the volunteers passing the basketballs for 10 seconds, have the seventh volunteer (dressed in dark colors) walk directly through the scene, from left to right in the video camera view, carrying an open umbrella over his or her head. The volunteers passing the basketball and the umbrella-carrying volunteer should take care to move around each other without hitting each other.
   5. After the umbrella-carrying volunteer has exited the scene, continue to record the volunteers playing for another 5–7 seconds, and then stop recording.

Inattentional Blindness Testing

1. Prepare what you are going to say to your test subjects. Write what you are going to say on a piece of paper if you need to. Here is an example:
   1. Today I will be conducting a simple observational test. It is designed to highlight how males and females think. I will be showing you a video of six people passing a basketball. Three people are dressed in light clothes and they are passing a basketball between themselves. Your job in this test is to count the number of times they throw the basketball to each other. To make the task more challenging, there are also three people dressed in dark clothes who are passing a basketball. Ignore these people and just concentrate on counting the number of passes that the people in light clothes catch.
2. Set up a viewing area with the television screen so that a test subject can watch the video comfortably. You can include a chair in the viewing area if you feel it necessary.
3. Bring in one test subject to the viewing area and have him or her sit or stand in front of the television. Note: Do not use any of the seven volunteers who helped you make the video as a test subject.
4. In your lab notebook, create a data table, like the one shown below. Assign each volunteer a number and also write down each volunteer's gender.

5. Ask the test subject to carefully listen to your speech that you wrote in step 1. Turn on the TV and the video and move to the side.
6. Once the video has finished, ask the test subject how many passes the volunteers wearing light clothes caught. Then ask if he or she noticed anything unusual. If so, ask what he or she noticed. Record whether the test subject noticed the person moving across the screen with the umbrella in your lab notebook. Thank the test subject for participating in the experiment and let him or her go.
7. Repeat steps 3–6 with each test subject until you have tested all of the test subjects.

Analyzing Your Data

1. Count the number of test subjects who didn't notice anything unusual about the video. Record this data in your lab notebook, along with the number of people who did notice something unusual about the video.
2. Plot the data on a graph. If you would prefer to make your plots online, use the following website: Create a Graph. Label the y-axis Number of Test Subjects. On the x-axis, label one bar Noticed Unusual Activity and another bar Did Not Notice Unusual Activity.
3. From your data, did inattentional blindness affect your volunteers? What kind of conclusion can you make about how people see unexpected and expected objects?