Introduction Electronic media are an integral part of university students' academic and personal lives; however, their excessive use may interfere with the cognitive functions critical for learning. Intelligence can be assessed through crystallized intelligence (Gc), which reflects accumulated knowledge, and fluid intelligence (Gf), which is associated with problem solving and adaptability. Also, neurophysiological measurements like the event-related potentials (ERPs), particularly P300, provide high temporal resolution measures of cognitive processing, allowing an assessment of attention (neurophysiological measures) and memory functions. This study hypothesizes that excessive screen time negatively impacts attention, fluid and crystallized intelligence, and academic performance in medical students. Materials and methods A total of 305 second-year medical students from a public university participated in the study (mean age: 20 years). Variables assessed included intelligence, attention, academic trajectory, and screen time. Intelligence was measured using the Shipley-2 test, and screen time was measured using a validated Screen Time Survey. For the neurophysiological measures, a subsample (n=30) underwent ERPrecording with the P300 oddball paradigm for neurophysiological analysis. Academic performance was determined from standardized physiology test scores. Data were analyzed using IBM SPSS Statistics for Windows, Version 25.0 (2017; IBM Corp., Armonk, New York, United States), GraphPad Prism (Dotmatics, Boston, Massachusetts, United States), and Excel (Microsoft Corporation, Redmond, New York, United States) through descriptive and inferential statistics. Results A significant relationship emerged between screen time, cognitive performance, and academic achievement. Participants reported an average daily screen exposure of 7.1 ± 4.3 hours. A negative correlation was identified between screen time and standardized test scores (r = -0.24, p < 0.001), indicating that increased screen use was associated with lower academic performance. Cognitive intelligence assessments revealed that Gf (R² = 0.848) and general cognition (R² = 0.400) were significantly affected, while Gc remained stable (R² = 0.001). Neurophysiological measures showed average P300 latencies of 358.33 ± 45.6 ms and amplitudes of 259.63 ± 61.6 μV. Shorter N100 latencies (86.7 ± 24.6 ms) correlated with better academic performance (r = -0.45, R² = 0.199). Discussion Students with greater screen time exhibited lower standardized exam scores, suggesting that excessive digital exposure may deplete the cognitive resources essential for academic tasks. The decline in fluid and general cognitive intelligence suggests a diminished capacity for problem-solving and adaptability. Neurophysiological markers indicated prolonged latencies and reduced amplitudes of key ERPs (N100, N200, and P300), reflecting impaired attentional control and working memory in students with higher screen exposure. These findings suggest that prolonged screen use contributes to slower and less efficient cognitive processing. Conclusions Excessive screen time, particularly due to recreational electronic media use, negatively affects cognitive performance and academic outcomes in medical students. The observed decline appears to be mediated by deficits in attention and working memory along with a reduction in Gf, which may impair problem-solving skills and adaptability in complex academic settings.
Read full abstract