For this lab you will be investigating the dissociation between visuospatial and verbal "codes" for cognition.

In Part I, you will be collecting data on two tasks to establish a baseline measure of visuospatial and verbal performance.

In Part II, you will choose an interference task and examine how it influences performance on the tasks in Part I.

In Part III, you will compare your baseline and interference performance.

Before you begin, make a table in your notes like the one below:

 Performance with Interference

Step 1. Corsi Block-Tapping Test (Baseline)

The Corsi Block-Tapping Test (or corsi blocks) is a psychological test that assesses visuospatial short term memory. You will now take a version of the corsi blocks test to determine your baseline visuospatial performance score.

Click this link to begin the test. When the test is over, you will see a screen that says "Your Corsi span is # items." Take the # from this test and add it to your table in the baseline performance row and under the visuospatial span column. If working in pairs or a group, take the average score and put it in the table. 

Step 2. Digit Span Test (Baseline)

The Digit Span Test is a psychological test that assesses verbal short term memory. You will now take a version of the digit span test to determine your baseline verbal performance score.

Click this link to begin the test. When the test is over, you will see a screen that says has the correct number as well as your answer and the level you got to "E.g., Level 6". Take the # from the level you got to and subtract 1 (this gives you the highest number of digits you were able to recall accurately). Add this # to to your table in the baseline performance row under the verbal span column.

Step 1. Choose a Secondary Task

The idea that there are two codes for cognition means that our mind processes visuospatial information and verbal information in different ways. This means that when we engage in a task like corsi blocks, we are using different cognitive resources than when we are engaged in a task like the digit span test. If these visuospatial and verbal tasks rely on different resources they should be dissociable (separable). In cognitive psychology, a common way to determine whether two things are dissociable is to look at whether a third factor influences the original two things in the same way.

For example, let's say we have two stones and we want to show they are different types of rock. If we just look at the two stones, they look identical. However, if we put both rocks in a bucket of water (a third factor) one floats and one sinks. Thus, we know they are dissociable because they behaved differently when put in water. In the current lab, visuospatial cognition and verbal cognition are our two stones, and the water is a secondary task you are going to come up with.

What is a secondary task? A task you perform AT THE SAME TIME as a primary task. In this lab, your primary tasks are corsi blocks and the digit span test. Your secondary task is any type of activity you can do while performing each of the primary tasks. For example, while doing either corsi blocks or the digit span test you could sing the lyrics of your favorite song loudly, do a dance in your chair, or keep up a conversation with the person sitting next to you.

You will now make up a secondary task that you think will interfere with one of the primary tasks (either corsi blocks or digit span) but NOT the other. Think about what cognitive resources your secondary task will rely on. For example, if the secondary task uses mostly verbal resources it may worsen performance on digit span but not corsi blocks. Once you choose your secondary task, write it down and continue to Step 2.

Step 2. Corsi Block-Tapping Test (Interference)

You will now take the corsi blocks test again, but this time engage in your secondary task while watching the blocks appear (you can stop the secondary task when entering your response).

Click this link to begin the test. When the test is over, you will see a screen that says "Your Corsi span is # items." Take the # from this test and add it to your table in the interference performance row and under the visuospatial span column. If working in pairs or a group, take the average score and put it in the table. 

Step 3. Digit Span Test (Interference)

You will now take the digit span test again, but this time you will engage in your secondary task while watching the numbers appear (you can stop the secondary task when entering your response).

Click this link to begin the test. When the test is over, you will see a screen that says has the correct number as well as your answer and the level you got to "E.g., Level 6". Take the # from the level you got to and subtract 1 (this gives you the highest number of digits you were able to recall accurately). Add this # to to your table in the interference performance row under the verbal span column.

Examine the values in your table to answer the following questions:

For the visuospatial span (corsi blocks), how did your secondary task influence performance?

For the verbal span (digit span test), how did your secondary task influence performance?

Which in which task did performance suffer more when adding the secondary task? Why?

Do your results support the idea that there are two codes for cognition? Why or why not?

Be ready to share the following with the class:

1. What was your secondary task?

2. What primary task did it interfere with more? (corsi blocks or digit span)