Abstract
Critical flicker fusion frequency (CFF) is the frequency at which flickering light can be perceived as continuous and it is used to assess the processing of temporal vision. It is of interest to compare critical fusion frequency (CFF) in mild, moderate & severe internet users. Cross sectional observation study was done among 350 professional students. Internet addictions for around 372 professional students & internet addiction was evaluated by Young's scale of Internet Addiction questionnaire in the age group 18-25 years. CFF was measured using an in-house built LED-based CFF M1 Model instrument. A total of 372 participants (in age group 19-22 years) were recruited. Of the participants 65 % of them were mild internet addictors, 48% were moderate and 7% were severe internet adductors. Among the internet usage, the Kruskal-Wallis test showed a significant difference in internet addiction score, duration of internet usage (hours) and average Critical fusion frequency (Hz) (P<0.001). For the average critical fusion frequency (Hz), the Dwass-Steel-Critchlow-Fligner test showed significant pairwise comparisons between the following: (1) mild internet addictor's vs moderate internet addictors and (2) Mild internet addictors versus severe internet addictors (p<0.001). Critical flicker fusion frequency(CFF) as it is an easy, quick, and non-invasive technique used as a general indicator of cortical processing, visual persistence for cognitive flexibility.