|Driving a car is highly complex and therefore causes driving error to be a high causal factor in road accidents. Because it requires constant management of cognitive processes like perception, decision-making, and execution of motor responses. It is therefore important to study driving behavior to ensure road safety. The paper of van der Heiden, Janssen, Donker and Merkx (2019) studied lane changing while performing a secondary task. However, the effects of primarily cognitively loading tasks on driving performance are not well understood yet. Therefore this paper extends their study with novel analyses. Firstly, this paper investigates which subscale of the TLX questionnaire is responsible for the decrease in drive performance when there is a higher level of cognitive distraction. Secondly, it is investigated if mental workload is a predictor of reaction time and distance. The third research question answers the question which underlying cognitive processes account for the different aspects of reaction time. The results showed that no specific subscale of the TLX is responsible for decrease in drive performance and there was no relationship found between reaction time, distance and mental workload. The third analysis showed drivers tend to shift from focus from the near point to the far point when they start driving faster. Furthermore drivers steer less abruptly when they drive faster with a focus on the far point. The last finding is about the delay period (the period in which the visual events are processed before action is initiated). This seems to be very important for this component T1. This information can be used to design safer roadways and enhance safety systems in cars by incorporating these cognitive processes.