The IMT/DMT (Dougherty, Marsh, & Mathias, 2002) is a continuous performance test that was designed to assess impulsive behavior. The Immediate Memory Task involves comparison of consecutively presented number and responding in those instances when the current number matches the number immediately before it (called a correct detection). The Delayed Memory Task similarly involves responding to matching numbers, but the numbers to be compared a separated by a filler sequence (e.g. 12345).
IMT/DMT instrument reference:
Immediate and delayed memory tasks:
a computerized behavioral measure of memory, attention, and impulsivity.
Dougherty DM, Marsh DM, Mathias CW (2002)
Behavioral Research Methods: Instruments and Computers, 34, 391-398. PubMed ID 12395555
For more information, the authors maintain a website for the IMT/DMT that can be accessed at: