Pilot Study to Assess Changes in the Blink Reflex Across Age

Abstract

The objective was to conduct a preliminary study to access blink reflex parameters across age using the Eyestat. The blink reflex is a primitive brainstem response to an external stimulus is affected by multiple neurologic disorders, including those that affect the dopaminergic circuit that controls the eyelid. Our laboratory has utilized a potential objective measure to identify concussions within a college aged sport population called Eyestat, which measures changes in blink reflex parameters. Prior research cited significant differences in various blink reflex parameters between active play, concussion, and baseline. However, data with older, non-athlete populations has not defined. One hundred forty three subjects between the ages of 8-80 participated in this study. Once the subject was seated, the test sequence was initiated, in which the subject placed their face into the mask and 5 random air puffs were applied to the corner of the left or right eyes over a course of 20 seconds. High-speed videography (280 frames/sec.) captured the response of the subject's eyes before and after each stimuli. Description statistics of the data indicated differences across age with the following parameters: Latency (ms): 46.02 (ages 8-21); 47.12 (ages 22-30); 48.96 (ages 31-40); 47.44 (ages 41-50); 55.20 (ages 51-60); and 55.39 (ages 61-80). Oscillations (qty): 14.10 (ages 8-21); 14.25 (ages 22-30); 12.19 (ages 31-40); 12.75 (ages 41-50); 9.98 (ages 51-60); and 9.78 (ages 61-80). Excursions (px): 127.57 (ages 8-21); 137.46 (ages 22-30); 135.34 (ages 31-40); 144.88 (ages 41-50); 147.72 (ages 51-60); and 148.85 (ages 61-80). Although more research is warranted to determine if these differences occur with a larger subject pool, this data substantiates the need for longitudinal assessments of the blink reflex as a potential biomarker, providing a non-invasive assessment of brain health in various populations.