The article discusses the study of high-speed scanning in human memory, focusing on how subjects judge whether a test symbol is contained in a short memorized sequence of symbols. The mean reaction time increases linearly with the length of the sequence, suggesting an internal serial-comparison process with an average rate of 25 to 30 symbols per second. The study uses two experiments to investigate the retrieval process, controlling for response and test-stimulus entropies. The results show that the latency of responses depends on the number of elements in memory, indicating an exhaustive scanning process. The linear regression analysis accounts for 99.4% of the variance in mean response latencies, with a slope of 37.9 ± 3.8 msec per symbol. The zero intercept is interpreted as the sum of motor response and other unknown processes, while the slope represents the mean comparison time. The findings suggest that high-speed scanning is a general process, independent of sensory and motor operations, and differ from parallel comparison processes. The study also notes that the generality of high-speed scanning needs further validation, considering the specific conditions of the experiments.The article discusses the study of high-speed scanning in human memory, focusing on how subjects judge whether a test symbol is contained in a short memorized sequence of symbols. The mean reaction time increases linearly with the length of the sequence, suggesting an internal serial-comparison process with an average rate of 25 to 30 symbols per second. The study uses two experiments to investigate the retrieval process, controlling for response and test-stimulus entropies. The results show that the latency of responses depends on the number of elements in memory, indicating an exhaustive scanning process. The linear regression analysis accounts for 99.4% of the variance in mean response latencies, with a slope of 37.9 ± 3.8 msec per symbol. The zero intercept is interpreted as the sum of motor response and other unknown processes, while the slope represents the mean comparison time. The findings suggest that high-speed scanning is a general process, independent of sensory and motor operations, and differ from parallel comparison processes. The study also notes that the generality of high-speed scanning needs further validation, considering the specific conditions of the experiments.