Analysis of blink rate patterns in normal subjects

Mov Disord. 1997 Nov;12(6):1028-34. doi: 10.1002/mds.870120629.


The present study measured the normal blink rate (BR) variations in relation to behavioral tasks in 150 healthy volunteers (70 males and 80 females; aged 35.9 +/- 17.9 years, range 5-87 years). The subjects were videotaped in a standard setting while performing three different tasks: resting quietly, reading a short passage, talking freely. The mean BR was computed during each task; the data were compared by means of analysis of variance and Student's t tests. Mean BR at rest was 17 blinks/min, during conversation it increased to 26, and it was as low as 4.5 while reading. As compared with rest, BR decreased by -55.08% while reading (p < 1 x 10(-15)) and increased by 99.70% during conversation (p < 1 x 10(-9)). As compared with reading, BR increased during conversation by 577.8% (p < 1 x 10(-17). The distribution curves were highly reproducible in each task. The best curve fit was represented by a log-normal distribution, with the upper tail of each curve having a normal distribution. Eye color and eyeglass wearing did not influence BR. Women had higher BR than men just while reading. No age-related differences were found. The most common BR pattern was conversation > rest > reading, which occurred in 101 subjects (67.3%); 34 subjects (22.7%) had the pattern rest > conversation > reading; 12 (8.0%) had the pattern conversation > reading > rest. This study identified three normal behavioral BR patterns and showed that BR is more influenced by cognitive processes than by age, eye color, or local factors. The present findings provide a normal reference for the analysis of BR in movement disorders such as dystonia or tics.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Blinking / physiology*
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Male
  • Middle Aged
  • Periodicity*
  • Reading
  • Sex Factors
  • Speech
  • Videotape Recording

Grants and funding