Objective of the Study: The objectives of this study were to compare the bispectral index (BIS) values during the solving of three different psychomotor tests and during the 5-minute relaxation periods before and after solving the test. Also, the goal of the research was also to determine the possible existence of a connection between the results of solving psychomotor tests of the examined students and their overall average grades in the study of medicine and the different groups of subjects. Subjects and methods: Our research included 30 participants, all whom were sixth year students at the Faculty of Medicine in Split. Each subject solved a total of three psychomotor CRD tests, the order of solving was randomized. Before each test, there was a practice of the test, then a relaxation period, which was followed by solving the test, the results of which were measured. After solving the last test, another relaxation followed. During all periods of relaxation and test solving, the subjects' BIS values were recorded using a disposable BIS electrode, BIS device and monitor. We obtained the average grades during the study from the ISVU system for a possible connection with the results of the psychomotor tests. ANOVA test for repeated measurments was used to compare BIS values during all three psychomotor tests, both with each other and with relaxation periods before and after a certian test. Correlation analysis was used to calculate the correlation between average grades and recorded reaction speeds on the test. Statistical significance was set at P <0.05. Results: A significant difference in BIS values was observed during the solving of three psychomotor tests in our research. BIS values were significantly lower when solving the test of arithmetic tasks (CRD 11) than when solving a test of speed of reaction to light stimuli (CRD 311) or a test of hand-leg coordination (CRD 411). In addition, BIS values while solving the CRD 11 test were significantly lower compared to the relaxation before and after the mentioned test, while this was not the case in the other two tests. There was no significant difference in BIS values during the relaxation before and the relaxation after solving the mentioned tests for all three CRD tests. The correlation between the calculated average grades and the results of the CRD tests was not statistically significant, although the CRD 11 with the average score of the preclinical morphology subjects (P=0.081) and the negative correlation of the speed of solving the CRD 411 test with the average score of the preclinical physiology subjects was very close to the threshold level of significance (P=0,071). Conclusion: This research confirms that BIS values were significantly lower during arithmetic problem solving test compared to light stimulus reaction speed test and arm-leg coordination test in medical students in our research. The stability of recorded BIS values during the relaxation period before and after psychomotor testing speaks in favor of the validity of this kind of research and the protocol we applied. In order to assess the correlation of success at the study (viewed only through the average grades on the exams during the study), our preliminary results show that the grades from the preclinical subjects were more related to the results of the psychomotor tests that we applied than the grades from the clinical subjects. Our results also indicate that the average scores on the preclinical morphology subjects could be more related to the arithmetic problem solving test, while the complex hand-foot coordination test is possibly more related to the average scores on the preclinical physiology subjects. For a better and more complete assessment of the connection between success at the study, assessed through the average grades on the exams during the studies, and the results on the applied psychomotor tests, additional research is needed on a larger number of subjects and in different universities.