Changing the task presentation time can significantly affect the time of problem solving. Research shows that when the task presentation rate increases, the time to complete it can decrease due to increased concentration and mobilization of cognitive resources. However, excessive acceleration can lead to errors and poorer performance due to stress and overload. The aim of this study was to identify quantitative criteria for assessing the ultimate possibility of reliably solving the cognitive and perceptual problems based on a comparison of the time needed to solve problems and the response of the cardiovascular system. The survey included test task performance (logical-combinatorial and perceptual tasks) and heart rate. Time for every task performance was fixed during the test session and limited (5 intervals in both tests of 10 min each with modeling different “time pressure”). We have revealed in our study that the ratio of the time of the test performance for 10 min and the tension of cardiac regulation by interbit intervals can be a quantitative measure of the limits of human capabilities for processing a stream of perceptual tasks. A significant criterion can be the measurement of the time of tasks’ solution in the perceptual test reduced to 0.62 of the average time it takes to solve such problems by this person without time limits.