This study investigates the relationship between the characteristics of drawn lines and reaction time in simulated right turn situation, considering that cars drive on the left side in Japan. Analyzing tablet-based task of drawing lines, it aims to predict cognitive influences on driver performance, providing valuable insights for accident prevention and road safety. 36 male participants completed line drawing tasks and simulated right turn performance tests. Significant positive correlations were found between variations in drawn lines, and variations in reaction time and total number of errors. Participants with significant variability in their drawn lines exhibited higher variations in reaction time and larger number of errors. From a t-test, there was a significant difference between the groups with small and large variation in their drawn lines with respect to the average reaction time. Participants with significant variability in their drawn lines tended to have longer reaction times. The results suggest that reaction time or number of errors can be predicted from the characteristics of drawn lines.