The phenomenon of banner blindness explains that users can mentally ignore online advertisements (ads). However, eye-tracking studies have shown that users still fixate on ads, and even without direct gaze, ads still fall within a user's peripheral vision, which may negatively overload cognition. It is therefore unknown how blind, banner blindness, truly is, and what other effect ads may have on user's information seeking. To address this gap, a withinsubjects design experiment was conducted with 37 participants who performed search tasks from the TREC 2017 Common Core News Collection, where 3 search tasks contained various types of ads, and one search task had no ads. Although our results showed that on average, participants retrieved similar amounts of relevant documents regardless of whether ads were present or absent, participants took significantly longer achieving this performance when ads were present. Furthermore, when ads were absent, participants reported less frustration, and not only believed they learned more, but a post-task recall test showed that participants actually did learn up to 38% more. Consequently, our findings suggest that banner blindness is more costly than just mere annoyance, and that the influence of ads on user's information retrieval recall may extend current theories of visual crowding.
CCS CONCEPTS• Information systems → Users and interactive retrieval; • Human-centered computing → HCI design and evaluation methods.