Post 2: Clinical Research at SERI

Driving in the simulator. Taking an exit off the highway to our digital ski resort – see the snow-capped mountains on the right?

Here at Schepens Eye Research Institute (SERI) in Boston, I have been working on four research projects. In the first project, we are investigating the relationship between visual impairment and auditory distraction as well as the effects of age on these interactions. In order to test this, we have subjects from two different age groups (young = 20-40, old = 60+) drive in our driving simulator (see picture above) while wearing goggles that simulate visual impairment and performing an auditory distraction task. The visual impairment goggles use dispersion filters to blur vision and simulate eye conditions such as cataracts. The auditory task involves listening to an audio book and repeating back certain words (such as “the”) every time they are said. This is a lot harder than it seems. Try it at home! But not while driving. During these drives, pedestrians appear, and the driver must honk each time they see one. Response times are recorded as well as data about the control and motion of the vehicle. [Note: If you or someone you know is a current driver in the Boston area, age 60+, you qualify to participate. We are still recruiting. Contact me.]

The second project I am helping with is related to the first. In this project, we use the same auditory task, but we leave out the goggles so that we can track head and eye movement. Our eye tracking device is unable to track eyes through the dispersion filters on the goggles, so in order to examine the effects of auditory distraction on gaze movements we must do without the goggles. The eye tracking device utilizes six cameras and infrared lights around the simulator. The data we receive from this is in the form of graphs of head and gaze movements surrounding pedestrian events. Here is an example of one of these plots:

This plot shows the head and gaze movements surrounding the presence of a pedestrian. The red line represents head movement, and the blue line shows gaze movement. Yellow and green lines along the blue line show glances. The two black vertical lines indicate the time that the pedestrian is on screen. The green dash at the top is the moment the horn is honked.

The third project I am helping with involves driving with a bioptic telescope, a device attached to glasses that people with visual impairments may use to help them drive and read street signs (see picture below). Unfortunately, the telescope creates a ring-shaped blind spot around that impairs vision. Therefore, during our experimental drives, we have signs that participants look at through the telescope and honk at pedestrians they see. We then examine the timing of how the head and eyes move to look through the telescope as part of a bigger study that examines the effect of this blind spot on pedestrian detection.

Bioptic telescope

In these three projects, I help to run subjects through our experiments, which involves obtaining consent, doing vision measures (including visual acuity, contrast sensitivity, and central visual field), and running them through the drives in the simulator. I also help to process and analyze the data we collect.

The final project I am working on is a telephone questionnaire that we are designing in order to gather information about how much drivers with visual impairments use in-vehicle assistive technologies (such as cruise control) and whether or not these devices are helpful. This project is in the beginning stages, and I have been helping to design the questionnaire, fill out paperwork, and pilot the questionnaire to make it clear and usable.

So far, I have been having a lot of fun and have learned a great deal about each step of the clinical research process. During my final few weeks, I hope to continue running subjects and learning more about data analysis.

For more information about the lab, visit the lab’s website here: http://bowerslab.eye.hms.harvard.edu/

If you are in the Boston area and are interested in participating in experiments here, let me know!

Week One at Schepens Eye Research Institute

Outside of Schepens

This summer I am doing an internship in clinical research at Schepens Eye Research Institute in Boston. Schepens Eye Research Institute of Massachusetts Eye and Ear Infirmary is an affiliate of Harvard Medical School, and one of the largest research organizations in the nation. Their mission is to eliminate blindness, and their labs perform research on all aspects of vision and vision loss. I am interning in a lab that researches the safety and considerations of driving with various visual impairments, particularly hemianopia (loss of vison in half of each eye). I am currently being trained to help with a project investigating the effects and interactions of three factors on driving: age, visual impairment, and auditory distraction. Experiments are conducted using a very realistic driving simulator. Before learning how to help run the study, I got to be a participant. Here is a picture of me cruising down the highway on the simulator:

Me driving the simulator

The simulator consists of five giant monitors giving it 220° of view surrounding a genuine car seat, steering wheel, pedals, and dashboard. It contains all of the components of a real car, including working digital rearview mirrors and speedometer. The seat moves to mimic the physical effects of turning or accelerating in a real car. The scene portrayed on the screens is from a virtual world where conditions can be manipulated, such as weather, time of day, and the presence and actions of pedestrians and other cars. These conditions are controlled in specific ways depending on the experiment being performed. The simulator is also equipped with cameras that can track head and eye movement data.

This week, I read articles to become familiar with this field of research, and began learning how to perform vision tests on subjects, how to run the driving simulator, and how to process data. Eventually I will be performing all of these tasks on real subjects in order to collect and process data. For this study, we perform two visual tests on all subjects: visual acuity and contrast sensitivity. Visual acuity is the overall accuracy or sharpness of one’s vision (a normal acuity is 20/20), and is measured by reading a chart of different sized letters. Contrast sensitivity is how well one can distinguish between light and dark, and is measured by reading a chart that has gradually fading letters.

Chart used to measure contrast sensitivity

 

Eye chart used to measure visual acuity

 

 

 

 

 

 

 

From this project, we hope to gain valuable information about the interactions between visual impairment and auditory distractibility. This information could be useful in the consideration of the safety of visually impaired drivers, or those considering obtaining a license.
I have known since high school that I have a strong interest in pursuing a career in ophthalmology. I hope that this internship will give me the opportunity to learn more about ophthalmology in both a clinical and research perspective. My goal for this summer is to gain experience that will affirm my decision to pursue a career in ophthalmology, and provide insight to help me to refine and discover my interests.

– Eliana Ellenberger