James Liao, MD,PhD


James Liao, MD,PhD

Name of Institution:

Cleveland Clinic, Cleveland, OH

Project Title:

External vs internal-triggered augmented-reality visual cues to treat freezing of gait

Investigator Bio:

Dr. Liao is Associate Staff in the Center of Neurological Restoration at Cleveland Clinic. His clinical and research interests are in Parkinson’s disease (PD) and related disorders where technologies like motion analysis, augmented reality, wearable sensors, neural signal recordings, and deep brain stimulation are used to assess and treat patients. He has a particular interest in the neural control of gait and gait impairment. Dr. Liao’s current research involves developing technology-based assessments and therapies for gait impairments and freezing of gait in PD. He sees patients with these types of disorders at Cleveland Clinic. Dr. Liao has a BS in electrical engineering and computer science from the University of California, Berkeley. He obtained his PhD in biomedical engineering in 2014 and his MD in 2016, both from Case Western Reserve University in Cleveland, OH. He completed his Neurology residency at Case Western Reserve University/University Hospitals Cleveland Medical Center, and a Movement disorders fellowship at Cleveland Clinic. He was appointed Associate Staff in 2022.


To study how augmented-reality cues can be used to ameliorate freezing of gait in PD.


Freezing of gait (FOG) is a “brief, episodic absence or marked reduction of forward progression of the feet despite the intention to walk” that eventually affects more than half of people with PD. FOG is associated with falls, morbidity, and mortality, yet medications or surgical treatments like deep brain stimulation do not universally help. On the other hand, gait cues like parallel floor lines are effective in reducing FOG. However, existing cueing techniques have drawbacks that limit their use in real-world situations. There is a need for a cueing technique that is on-demand and discreet – only perceptible to the patient. Fortunately, recent technological advances in augmented-reality (AR) enable such an approach. In this study, state-of-the-art AR glasses will be used to project digital cues that are only visible to the wearer, to determine if they can improve FOG.


We will recruit 36 individuals with PD and FOG to perform an obstacle-course gait task under six cue conditions: no cue, conventional cue, constant-on AR, patient-hand-triggered AR (turns on when patient clicks button), patient-eye-triggered AR (turns on when looking down), and examiner-triggered AR. The AR cue is a set of images that appear on the floor at a patient’s feet, mimicking floor lines. Gait performance will be captured on video and via body-worn wireless sensors that detect how each limb is moving. We will determine whether individuals are cue-able with conventional cues, whether intermittent cues outperform constant-on cues, and whether cues triggered by an examiner outperform cues triggered by patients themselves.

Relevance to Diagnosis/Treatment of Parkinson’s Disease:

If successful, this will be the first study to show that AR cues can improve FOG and could lead to widespread adoption of AR assistive cueing devices to treat FOG. Also, this study will inform the directions of future AR-based PD gait research, including whether to focus on developing closed-loop (intermittent, automatically-triggered) cues or whether to rely on constant-on or patient-triggered intermittent cues. In addition, by comparing FOG propensity across cue mechanisms, we may gain insight into the mechanisms of FOG, which are still incompletely understood. Ultimately, this project will lead to reliable and discreet treatments for FOG that improve quality of life and safety for people with PD.