Projects

N-Back

The N-Back test uses the classic n-back paradigm to assess working memory and cognitive control. The test has two versions: a 1-back version and a 2-back version. The test involves presenting a sequence of letters and asking the participant to indicate whether the current letter matches the one presented n steps earlier in the sequence. The "n" in the test refers to how many steps back the participant needs to compare the current stimulus.

In the 1-back version, participants are instructed to click "yes" if the current letter matches the letter from one step ago. For example, if the first letter is "A" and the second letter is "A," the participant should click "yes." If the first letter is "A" and the second letter is "B," the participant should click "no.".

In the 2-back version, participants are instructed to click "yes" if the current letter matches the letter from two steps back. For example, if the sequence starts with "A," "B," and the third letter is "A," the participant should click "yes." If the sequence starts with "A," "B," and the third letter is "B," the participant should click "no," as the letter does not match the one from two steps earlier.

In both versions, participants first view a brief animated tutorial explaining the instructions. Each letter is displayed for 2 seconds, and the trial times out after 5 seconds, requiring a response within that time. The test is typically administered in blocks of 20 trials (i.e., letters).