PURPOSE: This exploratory, pilot study compared the effects of concentrating on a visual task and a very mild ocular surface air stimulus on multiple blink parameters. METHODS: Ten subjects participated in this study. There were two visits, one with an ocular surface air stimulus (AS) and one without (NS). The AS was set at a level barely perceptible by subjects (approximately 0.6 m/s at the eye). At each visit, subjects performed a high-concentration (HC) and low-concentration (LC) task. Blinking was tracked and tear-film breakup (TBU) was monitored simultaneously to measure blink parameters, including the interblink interval (IBI), blink amplitude, duration, maximum velocity and TBU before and after each blink. RESULTS: During the HC tasks, IBI was significantly higher and blink duration was lower (repeated measures ANOVA, p < 0.05) than the LC tasks. The IBI in the AS-LC condition was significantly lower and less variable than in the NS-HC condition, whereas blink duration showed the opposite effect (Hotelling T² test, p < 0.005). There was high individual variation in correlations between blink amplitude and maximum velocity. The area of TBU was not significantly correlated with any blink parameter. CONCLUSIONS: The lack of correlation between TBU and blinking suggests that many blinks are stimulated by internal controls, rather than direct stimulation of the ocular surface by TBU. This pilot study suggests that even very mild ocular surface stimulation produces opposite effects on the timing and duration of the blink, when compared to concentrating on a visual task. The HC task tends to decrease blink frequency and duration, presumably to minimize interruption by the eyelids, whereas mild ocular surface AS increased blink frequency and duration, most likely to increase protection of the ocular surface.
PURPOSE: This exploratory, pilot study compared the effects of concentrating on a visual task and a very mild ocular surface air stimulus on multiple blink parameters. METHODS: Ten subjects participated in this study. There were two visits, one with an ocular surface air stimulus (AS) and one without (NS). The AS was set at a level barely perceptible by subjects (approximately 0.6 m/s at the eye). At each visit, subjects performed a high-concentration (HC) and low-concentration (LC) task. Blinking was tracked and tear-film breakup (TBU) was monitored simultaneously to measure blink parameters, including the interblink interval (IBI), blink amplitude, duration, maximum velocity and TBU before and after each blink. RESULTS: During the HC tasks, IBI was significantly higher and blink duration was lower (repeated measures ANOVA, p < 0.05) than the LC tasks. The IBI in the AS-LC condition was significantly lower and less variable than in the NS-HC condition, whereas blink duration showed the opposite effect (Hotelling T² test, p < 0.005). There was high individual variation in correlations between blink amplitude and maximum velocity. The area of TBU was not significantly correlated with any blink parameter. CONCLUSIONS: The lack of correlation between TBU and blinking suggests that many blinks are stimulated by internal controls, rather than direct stimulation of the ocular surface by TBU. This pilot study suggests that even very mild ocular surface stimulation produces opposite effects on the timing and duration of the blink, when compared to concentrating on a visual task. The HC task tends to decrease blink frequency and duration, presumably to minimize interruption by the eyelids, whereas mild ocular surface AS increased blink frequency and duration, most likely to increase protection of the ocular surface.
Authors: Craig Evinger; Jian-Bin Bao; Alice S Powers; Iris S Kassem; Edward J Schicatano; Victor M Henriquez; Kavita R Peshori Journal: Mov Disord Date: 2002 Impact factor: 10.338
Authors: Carolyn G Begley; Robin L Chalmers; Linda Abetz; Kitty Venkataraman; Polyxane Mertzanis; Barbara A Caffery; Christopher Snyder; Timothy Edrington; Daniel Nelson; Trefford Simpson Journal: Invest Ophthalmol Vis Sci Date: 2003-11 Impact factor: 4.799
Authors: Carlos Belmonte; Jason J Nichols; Stephanie M Cox; James A Brock; Carolyn G Begley; David A Bereiter; Darlene A Dartt; Anat Galor; Pedram Hamrah; Jason J Ivanusic; Deborah S Jacobs; Nancy A McNamara; Mark I Rosenblatt; Fiona Stapleton; James S Wolffsohn Journal: Ocul Surf Date: 2017-07-20 Impact factor: 5.033
Authors: Ziwei Wu; Carolyn G Begley; Nicholas Port; Arthur Bradley; Richard Braun; Ewen King-Smith Journal: Invest Ophthalmol Vis Sci Date: 2015-07 Impact factor: 4.799