The Spatial Delayed Response (SDR) Task or Oculo-motor delayed response (OMDR) task has been used extensively for assessing spatial working memory.

Subjects must focus on a central fixation cross on a computer screen. While fixated, a cue appears for 150 ms in one of 32 possible locations at a 4.5 inch radius from the central fixation. A delay period is then imposed. During the delay, a series of geometric shapes appear in place of the fixation cross. The subject must press the spacebar whenever the diamond shape appears. After the delay, the fixation cue returns, and the subjects must to point on the computer screen where they remember seeing the cue. Responses are measured in X and Y coordinates and compared to the actual location of the cue. Delay trials and trials with no mnemonic load (cue-present trials) are presented in a random order. Targets are evenly distributed between left and right sides of the screen. On the cue-present trials the cue is present during the response phase. This set of trials gives an indication of subjects’ pointing accuracy. Mean error in mm (distance between recall and actual target) is calculated for each subject for each type of trial.

File Number: CL0221 

Other Information:

State of Development
SDR Software has been extensively used:

Hershey, T., Craft, S., Glauser, T. & Hale, S. (1998). Short-term and long-term memory following early temporal lobe dysfunction. Neuropsychology, 12(1), 52-64.

Hershey, T., Bhargava, N., Sadler, M., White, N., Craft, S. (1999a). Standard vs. intensive insulin treatment in children with type 1 diabetes mellitus: Effects on memory and motor speed. Diabetes Care, 22(8), 1318-1324.

Hershey, T., Barr, W.B., Richards, K., Newcomer, J.W., & Miller, J.W. (1999b). Delayed response performance in temporal lobe epilepsy. Journal of the International Neuropsychological Society, 5(2), 122.

Hershey, T., Selke, G., Fucetola, R., Newcomer, J.W. (1999c). Spatial long-term but not working memory decreases over time in schizophrenia. Society for Neuroscience Abstracts, 25 (Part 1), 572.