The eye as a window into your pain tolerance

Vision Science graduate student, and winner of the provincial Three Minute Thesis (3MT) competition, pitches new method to quantify pain

Have you ever wondered why some people can swim for hours in a cold lake while others don’t last a minute? Everyone has a different tolerance for cold water, in much the same way that everyone processes pain differently.

Emmanuel Alabi, an optometrist and now a doctoral candidate in Waterloo’s School of Optometry and Vision Science, noticed it’s hard to predict how patients will handle the discomfort of routine medical procedures. That’s why he’s researching how the eye can be used as an objective measure of pain.

The surface of the eye, better known as the cornea, is one of the most densely innervated tissues on the body and is made up of a combination of both sensory and autonomic nerve fibres. The autonomic nervous system (ANS) is the primary control system for the human body, regulating internal functions such as heart rate and arousal. Within the ocular area, the ANS controls pupillary reflexes, focus and blood flow.

When introducing stimuli to the surface of the eye, Alabi observes pupil response and blood flow as factors to measure an individual’s pain tolerance. By characterizing these responses, Alabi and his supervisor, Professor Trefford Simpson, hope to develop objective metrics to quantify how much pain each individual experiences.

Alabi presented his research at the recent University-level Three Minute Thesis (3MT) competition, taking first prize and also winning the People’s Choice Award. He will compete in the Ontario 3MT competition being hosted on Wednesday, April 12 at the University of Waterloo.

Last year, Gah-Jone Won, a doctoral candidate in Faculty of Science’s School of Optometry and Vision Science, won the National 3MT Finals. Alabi is the third student from the Faculty of Science to compete at Provincials in the last five years. 

Alabi said, “I participated in the 3MT competition to share the research our lab does with the rest of the world; to let everyone know that science is not some abstract thing locked up in a highly classified laboratory, but rather part and parcel of our everyday lives from birth through adulthood.

Alabi hopes his research will be used in other fields by analyzing different areas of the body such as the surface of the skin. By conducting these measurements, medical experts will be able to clearly define patient tolerance instead of using a general self-reporting scale, which varies between individuals. It will also allow medical practitioners to properly predict the tolerance of those who are unable to communicate verbally, such as infants.    

Alabi said his passion for researching pain and autonomic responses continues to grow because of the unconditional support of his supervisor.

The Three Minute Thesis was first established in 2008 by the University of Queensland and is now a staple across many universities. It challenges graduate students to describe their research within three minutes to a public audience, using just one visual slide.