## 5 Discussion  
From the results, we can observe that collaborative scenarios where participants took the leader role presented more compelling scores in NASA-TLX's individual factors and overall workload alike. The latter implies that humans felt released, to some degree, from the various demands of the task, which is one of the main targets when designing anthropocentric HRCS. Moreover, strong positive correlations for overall workload with every individual factor were identified. This result is well adjusted to the theory of the NASA-TLX technique, as the six factors contribute in an important manner to the general construction of perceived cognitive workload. It was found, in particular, that sequential interactions were more sensitive to work role changes. Participants switching from follower to leader resulted in a significant decrease in both overall workload and mental demand. That is to say that when assigning responsibilities, experiencing a less proactive interaction with the robot companion may become a source of variation in cognitive ergonomics. Supportive scenarios were not considerably affected by this behavior. Another point to underline is the higher scores provided by participants in follower roles to physical demand and frustration. An initial lecture of this is that human operators executed more sections of the task on their own. They adopted a more passive part as they directed full attention to robot instructions and proposed work pace. In this case, nevertheless, some subjects expressed the necessity to act promptly and without restraints. Furthermore, coordinated physical contact with robots by workpiece handovers was not influential between interaction levels. We presume that objects with superior weights and sizes could represent differences in this matter. Performance was reviewed almost as ideal in the majority of surveys. It is worth mentioning that a low score in performance, unlike the other factors, implies a successful execution by the participants. This suggests that the desired outcome of the task might not be at risk, in principle, if selecting supportive or sequential interactions for similar quality inspection settings. Regarding temporal demand and effort, these were among the highest-rated factors across treatments. The participants did not perceive the task pace as slow or hurried. However, comments were made requesting a faster pace to perform  
Figure 5: Results of overall workload and spare mental capacity by collaborative scenario. additional activities and more autonomy to consistently respond better to the appearance of unforeseen events. According to the Bedford Workload Scale results, leader roles indicated higher levels of spare mental capacity in comparison to follower roles independently of the interaction level. This represents a larger availability of cognitive resources for the human counterpart even when managing robot actions, task instructions, and emerging issues. This is another target of anthropocentric HRCS in the context of Industry 4.0/5.0, where more emphasis on critical-thinking and problem-solving activities is pursued over monotonous physical-oriented labor. On the other hand, it is necessary to point out that participants rated workload as satisfactory without the need for reduction for the follower role scenarios. From our perspective, assigning human operators to follower roles can also benefit organizations, as it might be useful when oriented to training newcomers or introducing task variations to more experienced employees, even if potential learning effects initially arise. The physiological response of the participants, ultimately, showed no discrepancies throughout the four quality inspection scenarios. Nevertheless, the average heart rate of human operators had a positive moderate correlation with the overall workload. This result complies with the behavior reported in the current literature, where heart rate tends to increase along with workload.