Decrements in selective attention are a commonly experienced phenomenon that has practical implications for many industries. Two causes of such deficits are mental fatigue and alcohol intoxication, which impair selective attention by decreasing the efficiency of inhibitory processes. The present research examined the effects of these two factors on the selective attention subtest of the Useful Field of View test in both a baseline and an experimental session. Participants in the mental fatigue condition (n = 14) were tested while performing a divided attention task for two hours to induce mental fatigue. Those in the alcohol condition (n = 10) were tested while achieving a peak blood alcohol content of 0.05%. No differences between the two groups were observed, nor was a significant decline in selective attention observed as a result of either manipulation. The results indicate three possible explanations for this lack of a difference including a floor effect on the selective attention task, a pop-out effect in switching from the divided to the selective attention task, and an increase in attentional effort regulation due to the contrast in difficulty of the divided and selective attention tasks
