N- Back The DotBack test is presumed to measure executive control of the updating of information in working memory. The DotBack task is one in which the participant is presented a series of stimuli at a constant rate. The task of the participant is to map the currently presented stimulus on arrow keys of a keyboard to one they have recently seen in the stream (current, one, two or three positions back). Match criteria is the position of a ball in a fixed diamond frame on the screen and the participant is required to map the corresponding position on the arrow keys of the keyboard.
Test Phase
The test has four phases which are often referred as RuleSet or Category for the test in this specs. These Rulesets are named as :
Zero-Back (0-Back)
One-Back (1-Back)
Two-Back (2-Back)
Three-Back (3-Back)
Response Mode
When a response is made during the test, though there is no text coming up on the screen to acknowledge that but the stimuli will be changed as soon as the response was made, without waiting for the maximum allowed time to expire.
Output Variables Reaction Time : This is the time when a key press was recorded. Rule set: This is The RuleSet in which the stimuli was shown, this could be 0/1/2/3 denoting Zero Back, One Back, Two Back and Three Back respectively.
StimuliIndex : Which Stimuli of the above Rule Set was displayed (1,2,3…15, the max stimuli in any ruleset)
Expected response : The correct answer (Key press) for that stimuli (2/4/6/8)
Response Received : The response that was made by the user. (2/4/6/8 and 100 if no
response was made)
Response Type : If the response was Correct(C), In-Correct(I), Non-response(N)
Summary Variables
RuleSet (Rulse set of the stimuli)
Stimuli Index (Stimuli in that RuleSet)
CorrectResponse (Expected, correct response for the stimuli )
ResponseRcvd (Response received/made by user)
Result (Final result for the Response on that stimuli in the ruleset)