Visualization, (, Wiens, A. N. (4). Click the button below for the full-text content, 24 hours online access to download content. Everybody makes mistakes on this task. The Paced Auditory Serial Addition Test (PASAT) is a test of serial addition designed to assess information processing speed, working memory, and divided attention. The methods were identical to those of Experiment 1b. Finally, the majority of control subjects with abnormal minSOA z-scores and all abnormal TBI patients had abnormal dyad ratios, consistent with deficits in working-memory capacity to retain digits across trials. With regard to the findings presented by Roman et al. With increased severity and duration of post-concussion symptoms, PASAT performance is expected to decrease. (2005)  found that 16.1% of MS patients either declined to perform the PASAT or failed to complete testing at both 3.0 s and 2.0 s SOAs. Both education [r = -0.23 t(1615) = -9.50, p < 0.0001] and computer-use [r = -0.25, t(1615) = = 10.40, p<0.0001] had significant influences on performance, with both correlations significantly stronger than that of age [z = -2.65, p < 0.01, and z = -3.25, p < 0.005, respectively]. Large populations were studied in different laboratories by different experimenters. However, dyad ratios may decline precipitously at short SOAs among control subjects who adopt an “alternate answer” strategy [8, 35, 66]. Moreover, the demands on working memory are reduced because the subjects do not need to retain digits from one sum to the next. Not surprisingly, dyad ratios declined as SOAs were reduced, averaging 0.82 in the first half of the 54-trial test, and 0.72 in the second half [F(1,1436) = 748.59, p <0.0001, ω2 = 0.15]. The test administration methods were identical to those described in Experiment 1b. Minimum SOA z-scores, calculated after factoring out the influence of these factors, were virtually identical in the two control groups, as were response times (RTs) and dyad ratios (the proportion of hits occurring in dyads). (2005) . Subject z-scores were calculated after factoring out the influence of these factors using the regression equation minSOA = 2680.88 + 6.36*Age -33.56*Education -53.07*Computer-use. Using the bottom quintile of training accuracy as a cutoff, 87% of malingerers with abnormal z-scores showed training performance within the normal range seen in Experiment 1a, versus 31% of the controls with abnormal z-scores (i.e., 87% sensitivity and 69% specificity). In contrast, patients with severe TBI (sTBI) generally show persistently impaired performance on the standard PASAT [1, 84–86] and the adjusting PASAT . As in Experiment 1a, the three-factor regression (Age, Education, and Computer-use) accounted for more variance (13.0%) than a 2-factor regression with Age and Education (10.8%). Abnormalities in simulated malingerers tended to be greater than those of control subjects with abnormal scores (see Fig 3). To facilitate an understanding of the cognitive difficulties experienced following brain injury, the present study intends to analyze cognitive processes tapped by the Paced Auditory Serial Addition Test (PASAT), a test shown to be highly sensitive to the effects of brain injury.