The Effects of Repeated Testing, Simulated Malingering, and XXXX on High-Precision Measures of Simple Visual Reaction Time.

@entity1 @entity854 @entity131
Simple reaction time (SRT), the latency to respond to a stimulus, has been widely used as a basic measure of processing speed. In the current experiments, we examined clinically-relevant properties of a new SRT test that presents visual stimuli to the left or right hemifield at varying stimulus onset asynchronies (SOAs). Experiment 1 examined test-retest reliability in 48 @entity1 who underwent three test sessions at weekly intervals. In the first test, log-transformed (log-SRT) z-scores, corrected for the influence of age and computer-use, were well predicted by regression functions derived from a normative population of 189 control @entity1 . Test-retest reliability of log-SRT z-scores was measured with an intraclass correlation coefficient (ICC = 0.83) and equaled or exceeded those of other SRT tests and other widely used tests of processing speed that are administered manually. No significant learning effects were observed across test sessions. Experiment 2 investigated the same @entity1 when instructed to malinger during a fourth testing session: 94% showed abnormal log-SRT z-scores, with 83% producing log-SRT z-scores exceeding a cutoff of 3.0, a @entity854 never seen in full-effort conditions. Thus, a log-SRT z-score cutoff of 3.0 had a sensitivity (83%) and specificity (100%) that equaled or exceeded that of existing symptom validity tests. We argue that even expert malingerers, fully informed of the malingering-detection metric, would be unable to successfully feign impairments on the SRT test because of the precise control of SRT latencies that would be required. Experiment 3 investigated 26 @entity1 with @entity131 ( @entity131 ) tested more than 1 year post-injury. The 22 @entity1 with mild @entity131 showed insignificantly faster SRTs than controls, but a small group of four @entity1 with severe @entity131 showed slowed SRTs. Simple visual reaction time is a reliable measure of processing speed that is sensitive to the effects of malingering and @entity131 .
