Blink Rate and Incomplete Blinks in Six Different Controlled Hard-Copy and Electronic Reading Conditions

Abstract

PURPOSE. To evaluate spontaneous eye blink rate (SEBR) and percentage of incomplete blinks in different hard-copy and visual display terminal (VDT) reading conditions, compared with baseline conditions. METHODS.A sample of 50 participants (29 females, age range, 18-74 years) were recruited for this study. All participants had good ocular health and reported no symptoms of dry eye (OSDI score < 15). Face video recordings were captured while participants observed in silence a landscape picture at 2 m (baseline) and during six different, 6-minute controlled reading experimental conditions. Texts were presented in electronic (tablet and computer display at 100% and 330% zoom levels) and hard-copy (text in book position in silence and aloud and text pasted on the computer display) formats. Video analysis was subsequently conducted to assess blink parameters.RESULTS. All reading conditions resulted in a decrease in SEBR when compared with baseline conditions (all P < 0.001), with the least negative impact corresponding to reading in a 330% expanded display. The percentage of incomplete blinks was found to increase when reading was conducted on an electronic platform, in contrast to hard-copy text.CONCLUSIONS. The high cognitive demands associated with a reading task led to a reduction in SEBR, irrespective of type of reading platform. However, only electronic reading resulted in an increase in the percentage of incomplete blinks, which may account for the symptoms experienced by VDT users.Keywords: blinking amplitude, saccades, spontaneous eye blink rate, reading task OBJETIVOS. Evaluar la frecuencia espontánea de parpadeo (FEP) y el porcentaje de parpadeos incompletos en diferentes condiciones de lectura, incluyendo texto en papel y en terminales de visualización de datos (TVD), en comparación con condiciones baseline.MÉTODOS. Una muestra de 50 participantes (29 mujeres, edades entre 18 y 74 años) fue reclutada. Todos los participantes tenían buena salud ocular y no presentaban síntomas de ojo seco (OSDI < 15). Se capturaron vídeos mientras los participantes observaban en silencio una imagen situada a 2 metros (baseline), y en seis diferentes condiciones controladas de lectura (durante 6 minutos). Los textos se presentaron en formato electrónico (tableta, pantalla con un nivel de zoom de 100% y de 330%) y papel (libro en silencio y en voz alta y texto pegado encima de la pantalla). Posteriormente, se analizaron los vídeos para evaluar los parámetros del parpadeo.RESULTADOS. Todas las condiciones de lectura provocaron una disminución de la FEP al compararlas con el baseline (todas las P < 0.001), siendo el impacto menos negativo en el caso de la pantalla expandida a 330%. El porcentaje de parpadeos incompletos aumentó durante la lectura electrónica, en comparación con papel.CONCLUSIONES. La demanda cognitiva asociada a la lectura origina una disminución en FEP en todas las plataformas de lectura. Sin embargo, sólo la lectura electrónica ocasiona un aumento del porcentaje de parpadeo incompleto, lo que puede explicar l...

Changes in blink rate and ocular symptoms during different reading tasks

“…We found that reading a book reduced the blink rate more than reading text on an electronic device; this is in agreement with the work of Argilés et al23 They found that the blink rate was significantly lower when reading a book than text on an electronic device (9.7 inch tablet). Although the blink rate was higher when the electronic device was used, employment of an electronic device increased the incidence of incomplete blinks compared with hard copy reading condition 23…”

“…This is in agreement with the findings of previous studies; blink rates dropped significantly under different reading conditions 26. One possible explanation is that the attentional demand is higher during reading tasks, perhaps reducing the blink rate 23. Alternatively, use of the down-gaze position may be preferred during reading, which could in turn reduce the blink rate 3…”

“…It has been suggested that the reduction in blink rate during down-gaze viewing could be due to the decrease in the eyelid aperture 25. Therefore, decreased corneal exposure and less drying of ocular surface would be expected in comparison with primary gaze 23. This could be the reason for immediate reduction in blink rate found in this study during performing reading tasks.…”

“…The spontaneous blink rate has been reported to range between 12 and 18/min 3,23,24. The reason could be that, in our current study, we did not exclude subjects who might be classified as frequent blinkers (blink rate of >21/min) 25.…”

Spectral radiance of blue light filters on ophthalmic lenses

“…One of the most prevalent problems associated with CVS is dry eye [4]. Researchers have reported that ocular discomfort, specifically dry eye symptoms, may be associated with an increase of incomplete blinks (that is, the eye is not completely closed in the downward process of a blink) when electronic displays are used [5].…”