A – 37 Impact of Test Familiarity on Processing Speed and Accuracy in the URI–UCLA Memory Interference Test

Abstract Objective This study investigated whether familiarity with the URI–University of California, Los Angeles (UCLA) Memory Interference Test (MIT) influences cognitive performance and processing speed. The primary objective was to compare individuals completing the MIT for the first time to those with prior experience, with the hypothesis that prior familiarity would improve performance outcomes. Method Data were obtained from the URI–UCLA Memory Interference Test (MIT) database, including 13,805 participants performing the test for the first time (“Yes” group) and 644 participants with previous experience (“No” group). The primary dependent variables were the number of correct responses across sets 1–3 (cognitive accuracy) and average response time in milliseconds (processing speed). All participants completed the same standardized test battery in a community-based setting. Results Median correct responses were similar between groups (first-time: 138.0; prior experience: 137.0), with an observed effect size of 1.0 and a non-significant p-value (0.4376), indicating no substantial difference in accuracy. However, average response times differed significantly: the first-time group had a median of 809 ms, while the prior experience group had a median of 786 ms. This yielded an observed effect size of 23.0 and a highly significant p-value (< 0.0001), demonstrating that prior familiarity with the MIT was associated with faster response times. Conclusion Familiarity with the URI–UCLA Memory Interference Test did not affect cognitive accuracy but was associated with significantly faster processing speed. These findings suggest that prior experience enhances task efficiency without impacting accuracy. Further research is warranted to explore the mechanisms underlying improved response times in experienced participants.