“found that when people multitasked, their facial expressions displayed more negative emotions, particularly anger, which you can see in Figure 3. When they did not multitask, their emotional expressions were more neutral.26 Interestingly, when people received the emails all at once, their expressions showed a rise in anger during the time they were working on the emails compared to when they worked on the essay task. We also gave participants the NASA-TLX scale, described earlier in Chapter 5, and those who were continually interrupted assessed themselves as having higher mental load and effort.”