Think back two posts ago. I mentioned how some everyday experiences can cause stress reactions in people with autism. Add eye contact to that list. Several studies have shown that direct eye gaze from others can bring on physiological signs of stress in those with autism. Again, here’s where our lab’s research comes to bat. In a recently completed study, we hypothesized that by blocking the stress response system in people with autism, eye contact may be become more easy. Just as in the other study, we used propranolol, a drug designed to block receptors in the brain that are a part of the stress response system.
In this study, we examined eye contact via a machine that tracks the location of eye gaze. This machine, called an eye tracker, can tell us where a participant is looking and how long they look there. To mimic the direct gaze of another person, we used video clips of people looking directly at the video camera. We had research participants with autism view 32 of these clips on two different study days. Just as before, we compared the effects of propranolol, given on one study day, versus placebo (a sugar pill), given on the other. Overall, we hoped to see a benefit of propranolol in improving eye contact, or increasing the time the participants spent looking at the eyes of the people in the video clips.
Here’s the interesting part about science. 99.999% of the time, you don’t find exactly what you expect. We did not see differences between propranolol and placebo in eye contact. However, we did find that propranolol significantly decreased the amount of time our participants spent looking at the people’s mouths in the video clips. What does this mean? We are not entirely sure.
Is looking someone in the mouth an impairment linked to reduced eye contact or is it an adaptive strategy used to cope with the stress of eye contact? And how does the effect of propranolol on mouth gaze fit into the picture? As is common in the field of autism research, our findings produced more questions than answers. All the more reason to keep asking.
[This post was originally published at my previous blog, Neurolore.]