Effect of Computer Screen Background Hues on Attention, Memory, and Visual Task Performance in Medical Students: A Repeated Measures Pilot Study.

BACKGROUND

Digital screen characteristics may influence visual comfort, circadian physiology, and cognitive performance. Although blue-enriched light has been extensively studied, less is known about whether the background hue of a computer screen affects short-duration cognitive task performance. This study compared balanced white, red-predominant, and blue-predominant computer-screen conditions with printed white paper in medical students.

METHODS

Thirty medical students completed four testing sessions one week apart in a repeated-measures design. The visual conditions were balanced white, red-predominant, and blue-predominant computer-screen hues, and printed white paper. Cognitive performance was assessed using an author-developed PQBD letter-identification task, a picture-difference task, comprehension-based multiple-choice questions (MCQs), and the Pittsburgh Sleep Quality Index (PSQI). Differences across conditions were analyzed using the Friedman test, with Wilcoxon signed-rank post-hoc comparisons and Holm correction. Kendall's W was reported as an effect-size measure.

RESULTS

Paper was associated with the highest performance on several tasks, while the red screen condition performed better than the balanced white screen on selected attention and recall outcomes. PQBD performance differed significantly across conditions (Friedman χ²(3) = 37.08, p < 0.001; Kendall's W = 0.412). Mean correct-response percentages were 71.40 ± 17.31% for white screen, 81.26 ± 10.35% for red screen, 80.63 ± 9.51% for blue screen, and 89.92 ± 11.54% for paper. Picture-difference performance also differed significantly (χ²(3) = 26.15, p < 0.001; W = 0.291), as did comprehension-based MCQ performance (χ²(3) = 52.03, p < 0.001; W = 0.578).

CONCLUSION

Short-duration cognitive task performance differed across visual conditions in this exploratory repeated-measures study. Printed paper showed the highest performance on several tasks, while red-predominant screen hue was associated with better performance than balanced white on selected outcomes. Because the study used a small sample, fixed condition order, exploratory cognitive measures, and software-based rather than spectroradiometrically calibrated display settings, the findings should be interpreted cautiously. It appears that background hues of computer screens can affect task performance involving memory and concentration capabilities of medical students. Paper should be preferred in tasks requiring cognitive function, including memory and attention.