Gang Luo, Ph.D.

Harvard Medical School

Associate Professor of Ophthalmology

Schepens Eye Research Institute of Massachusetts Eye and Ear

Associate Scientist

Research Summary

Center/Research Area Affiliations

Biography

Dr. Luo's past experience as a research engineer, including his work with optics, image processing, and biomedical engineering, has influenced his interest in the mechanisms of the human visual system. He studies assistive technology for individuals with visual impairments. In particular, his current research includes the development of portable collision warning devices, including smartphone-based technologies, to improve walking mobility. He also studies driving behaviors in individuals with visual impairments.

Education

M.S., Ph.D., Chongquing University, China (1994, 1997)

Postgraduate Training

Fellowship, Nankai Univesrity, China (1997-1999)
Fellowship, Schepens Eye Research Institute of Mass. Eye and Ear (2002-2004)

Honors

2014: Alice Alder Fellowship, Harvard Medical School
2012: William F. Milton Award, Harvard University
2009: Best Fellow Paper, Schepens Eye Research Institute of Mass. Eye and Ear
2008: Hochhausen Access Technology Research Award, Canadian National Institute for the Blind
2007: Gordon Conference Travel Award, Oculomotor System Biology
1996: First Prize of China Instrumentation Society Award

His Story

Much of Dr. Luo’s research work aims to mitigate vision loss problems through innovative engineering approaches that are based on understanding of mechanisms in the human visual system. He is interested in developing novel engineering techniques, as well as evaluating those techniques rigorously in actual operation environments, to find evidence of practical benefits the technologies can bring to the patients.

Assistive Technology for Visual Impairments

For instance, he developed a smart phone app called SuperVision+ for vision assistance. The app offers supreme image stabilization, helping individuals read everything from small print to signs in the distance. Dr. Luo also developed a portable collision-warning device.

He collects user data to evaluate the practical usefulness of these devices. Similarly, he develops computerized analysis tools to mine big data collected in naturalistic driving studies involved with drivers who are visually or cognitively impaired.

Collection and analyses of these behavior data are technically challenging, but the research method provides unprecedented insights into the needs of patients, environmental and human factors, as well as evidence that can help understanding the causal relationship between interventions and effects. This research method based on behavior data from the real world represents an important advance in low vision research.

Basic Research on Eye Movement

Dr. Luo also conducts basic research on eye movements and associated visual perception. His studies on eye movements in people with tunnel vision or hemianopia revealed the important role of top-down eye movement control. His studies on peri-saccadic mis-localization provided strong evidence to rebut the long-standing saccadic spatial compression theory. His collision perception studies showed intact spatial motion perception in tunnel vision patients and impaired spatial vision in people with Alzheimer’s disease.

Novel Engineering Techniques

Dr. Luo’s vision research has also led to novel engineering techniques, such as an improved gaze contingent display system and an innovative computer vision algorithm for collision prediction. These have been used in a wearable collision-warning device for individuals who are blind or visually impaired people, as well as a vehicle anti-collision device, and the computerized analysis of naturalistic driving videos aforementioned.

Projects

Research Interests

  • Image processing
  • Assistive technology
  • Vision science

Long-Term Recording and Automated Analysis of Daily Driving Behavior

Driving behaviors in individuals with visual impairments are not well understood. For instance, it is a highly controversial issue whether people with poor visual acuity should drive with bioptic telescopes.

Dr. Luo is leading a study to address this question. He has developed an in-car recording system that can record video, GPS, vehicle black-box, etc., for months. He is also developing an automated analysis system to select important driving segments from the vast amount of data for manual evaluation by professionals. Selected driving procedures are reconstructed on an interactive interface, which provides detailed information about geographic location, speed, traffic videos, head movement, etc. Watch a video of the recording system in action.

Mobility Assistance Devices

The mobility needs of individuals with visual impairments have been receiving more and more research attention, as it is an important factor that impacts an individual’s employment opportunities and independence.

Dr. Luo’s laboratory is developing technologies to help people with impaired vision travel efficiently, walk safely, and drive safely. With funding from the U.S. Department of Defense, the researchers are currently developing a wearable, collision-warning device for individuals who are blind or visually impaired. (Watch a video of the device.) A rigorous clinical trial study to evaluate its usefulness is ongoing.

Mobile Computing Technology for Visually Impaired

Dr. Luo’s laboratory is developing mobile device (smart phones, tablets Google Glass) based technologies for eye care professionals and individuals with visual impairments. With expertise in image processing, Dr. Luo created a magnifying app with image stabilization capability. (Watch the video.) One of his apps, known as SuperVision+, is already on the market for free. He is also conducting clinical studies to evaluate mobile computing visual aid technologies.

Peri-Saccadic Visual Perception

A stimulus flashed shortly before a saccade—rapid eye movement between fixation points—will be mislocalized. Since the mislocalization is toward saccade goal, it is interpreted as saccades-cause spatial compression (Ross, Nature 1997).

Dr. Luo’s study showed that although a stimulus may be mislocalized, the size is still perceived unchanged. It is suggested that visual localization and perception of object size are separated. This provides some evidence to support the theory of separate “what” and “where” visual systems (Mishkin and Ungerleider, Trends in Neurosciences, 1983). Dr. Luo is conducting research to understand the mechanism underlying the peri-saccadic mislocalization. A recent finding indicates that the mislocalization locus is not necessarily at saccade goal. It can fall on a salient distracter that is far from the saccade goal.

Publications

Selected Publications

Dr. Luo has published more than 20 peer-reviewed articles. Below is a list of selected publications.

  1. Doherty AL, Peli E, Luo G.Hazard detection with a monocular bioptic telescope. Ophthalmic Physiol Opt. 2015 Sep; 35(5):530-9.
  2. Pundlik S, Tomasi M, Luo G. Evaluation of a portable collision warning device for patients with peripheral vision loss in an obstacle course.Invest Ophthalmol Vis Sci. 2015 Apr; 56(4):2571-9.
  3. Houston KE, Woods RL, Goldstein RB, Peli E, Luo G, Bowers AR. Asymmetry in the Collision Judgments of People with Homonymous Field Defects and Left Hemispatial Neglect.Invest Ophthalmol Vis Sci. 2015 Jun;56(6):4135-42.
  4. Yu D, Zheng J, Zhu R, Wu N, Guan A, Cho KS, Chen DF, Luo G. Computer-aided analyses of mouse retinal OCT images - an actual application report. Ophthalmic and Physiological Optics. 2015 Jul;35(4):442-9
  5. Tomasi M, Pundlik S, Luo G. FPGA-DSP co-processing for feature tracking in smart video sensors. Journal of Real-Time Image Processing. Special Issue Paper. 2014; 1-17.