One Back Test

The One Back Test uses an n-back paradigm to measure working memory.

Administration Time (in healthy volunteers): 4 Minutes

Cognitive Domain Measured: Working Memory

One Back Test Description

The pre-test on-screen instructions ask: “Is the previous card the same?” The test supervisor will read the test instructions from the script. To begin the test, the test supervisor or subject must press the “Enter” key.

A playing card is presented face up in the center of the screen. The subject must decide as each card is presented whether it is identical to the one just before. Therefore the first answer is always “No”. If the face up card is identical to the one presented immediately before it, the subject should press the “Yes” key, if it is not the same the subject should press the “No” key. The card in the center will go to the back of the pack revealing the next card. As soon as it does the subject must decide whether or not it is the same as the card he/she has just seen.

The subject will practice until they reach the required number of responses, or until the practice period expires.

Then, on screen instructions for the real test are presented. The test supervisor or subject must press the “Enter” key to begin the real test.

The subject should be encouraged to work as quickly as he/she can and be as accurate as possible. For example, the subject should try not to press either “Yes” or “No” key before a card turns over. If the subject makes a mistake he/she will hear an error sound.

Primary Outcome measure

Unit of measurement: Log10 milliseconds

Description and interpretation of scores: Speed of performance; mean of the log10 transformed reaction times for correct responses. (Lower score = better performance)

Two Back Test

The Two Back Test uses an n-back paradigm to measure working memory.

Administration Time (in healthy volunteers): 4 Minutes

Cognitive Domain Measured: Working Memory

Two Back Test Description

The pre-test on-screen instructions ask “IS THE CARD THE SAME AS THAT SHOWN TWO CARDS AGO?” The test supervisor will read the test instructions from the script. To begin the test, the test supervisor or subject must press the “Enter” key.

A playing card is presented face up in the center of the screen. The subject must decide as each card is presented whether it is identical to the card presented two cards previously. Therefore the first two answers are always “No”. If the face up card is identical to the one presented two cards previously, the subject should press the “Yes” key, if it is not the subject should press the “No” key. The card in the center will go to the back of the pack revealing the next card. As soon as it does the subject must decide whether or not it is the same as the card they saw two cards previously.

The subject will practice until he/she reaches the required number of responses, or until the practice period expires.

Then, on screen instructions for the real test are presented. The test supervisor or subject must press the “Enter” key to begin the real test.

The subject should be encouraged to work as quickly as he/she can and be as accurate as possible. For example, the subject should try not to press either “Yes” or “No” key before a card turns over. If the subject makes a mistake he/she will hear an error sound.

Primary Outcome measure

Unit of measurement: Arcsine proportion correct

Description and interpretation of scores: Accuracy of performance; arcsine transformation of the square root of the proportion of correct responses. (Higher score = better performance)