A Study of Critical Flicker Fusion Threshold among Smartphone Users

The critical flicker fusion frequency (CFF) is the frequency at which a flickering stimulus is perceived to be constant; the quick recognition of variation in stimuli indicates the active coordination between eyes and brain. When human eyes get exposed to the light radiating from Smartphone screen for longer period that driven us into recognizable mental and visual fatigue results in sleep disturbances, mood fluctuations, insomnia, dry eyes, computer vision syndrome, misconceptions and tactile hallucinations. In the present study the CFF frequency test has been used to evaluate the mental and visual fatigue due to continuous Smartphone overuse. Total 160 respondents (80 girls and 80 boys) of 18 to 24 years age group were randomly selected for baseline data out of which 10 percent i.e. 16 (8 girls and 8 boys) respondents were selected to assess the change in critical flicker fusion (CFF) frequency among the Smartphone users before and after usage. Critical fusion frequency was recorded by Flicker Fusion Apparatus. The findings of the study showed that there was slight decrease in fusion and flicker frequency in both eyes of the respondents that indicated the visual fatigue in the respondents due to Smartphone use for longer period. There was no significant difference between before and after case of CFFF rate in participants. Decreased CFF frequency after using Smartphone indicated visual and mental fatigue in participants. The slight variation in CFFF rate may not giving instant effect but indicated the point of concern for heavy Smartphone users as its impact will be emerge in later phase of life.