Research Interests

  • How vision impairments affect driving
  • Relationship between driving performance and novel tests of vision and attention
  • Evaluation of optical and electronic devices for visually impaired people while driving and walking

Research Methods

The Bowers Laboratory uses the realistic, but controlled environment of a high-fidelity driving simulator to evaluate the impact of central vision loss (e.g., due to age-related macular degeneration), peripheral vision loss (e.g., due to glaucoma or retinitis pigmentosa) and hemianopic visual field loss (loss of half the field of vision e.g., after a stroke). The laboratory is evaluating the effects of these vision impairments on detection of hazards while driving, on steering and lane-keeping skills, and on eye and head movement behaviors. When evaluating the benefits of optical devices for mobility tasks, we use two main approaches:

  • Laboratory-based studies, including assessments in controlled environments such as the driving simulator
  • Multicenter clinical trials using community-based, low vision clinics where the primary outcome measures are clinical success (whether the devices are still being used six months after being prescribed) and participants’ reports of the benefits of the devices (assessed by questionnaires)


Driving with hemianopia

This project continues Dr. Bowers’ prior research on driving with hemianopia. The current study is investigating the ability of people with hemianopia to compensate for the hemifield loss by scanning (eye and head movements) in realistic scenarios involving a range of different hazards within the safe environment of the driving simulator. We are interested in the question of why some people with hemianopia compensate well by scanning yet others do not. In later stages of the project we will evaluate a novel intervention aimed at improving the scanning of drivers with hemianopia.

simulator image                 miniSim

                             FAAC driving simulator                                                                             Custom-built compact driving simulator

Why do drivers fail to see hazards at intersections?

The aim of this project is to understand more about the factors that may contribute to the finding that older drivers are more likely to be involved in intersection crashes than middle-age drivers. Interestingly, people sometimes report that they looked but failed to see the vehicle with which they crashed. We are using novel laboratory tests of visual attention and peripheral vision, complemented by more real-world tests in the driving simulator to investigate this observation. Using eye and head tracking we are recording whether older drivers actually fail to look in the direction of a hazard and do not see it, or whether they look directly at the hazard but do not consciously see it.

Evaluating interactions between drivers and pedestrians

In collaboration with colleagues from the Chair of Ergonomics, Department of Mechanical Engineering, Technical University Munich we are using a novel arrangement of two linked simulators to evaluate the effects of vision impairment on the social interactions between drivers and pedestrians.

Driving with bioptic telescopes

People with reduced visual acuity are permitted to drive in 45 states with the aid of a small telescope, called a bioptic telescope, mounted at the top of their spectacle lens. The aim of the project is to investigate when and how bioptic telescopes are used and the safety of driving with bioptic telescopes. Using an in-car recording system and computerized analysis programs, we will record participants' daily driving activities for several months and then automatically process the vast amount of data to select segments of interest for analysis. This naturalistic driving evaluation will be complemented by lab-based tests and driving simulator evaluations. This project is being conducted in collaboration with Dr. Gang Luo.


Collision warning device for people with blindness or severe vision loss

People with total blindness or severe vision loss often use a long cane when walking to warn them of potential obstacles in their path. However, the traditional long cane only detects objects at ground level. Dr. Gang Luo and colleagues have developed a collision warning device to provide long-cane users with warnings of potential collisions from objects above ground level (e.g., over-hanging tree branches). The goal of this project is to establish a strong evidence base for the functional efficacy of the device by conducting a randomized controlled clinical trial of the device in which participants use the device in their daily activities for one or two months.

Collision Warning Device