By Gearóid ÓLaighin and Ian Gallivan,  NUI Galway’s School of Engineering & Informatics. Reused with permission.

A team of researchers at the National University of Ireland Galway (NUI Galway) have developed a wearable electronic device (cueStim) to prevent Freezing of Gait in Parkinson’s disease and preliminary results, following testing on a group of persons with Parkinson’s (PwP) in Scotland, are promising.

Parkinson’s disease (PD) is the second most common neurodegenerative disease in the developed world. There are approximately 1.2 million people living with PD in the EU [1] and it is estimated that nearly one million persons will be living with Parkinson’s disease (PD) in the U.S. by 2020 [2]. Approximately 60,000 Americans are diagnosed with PD each year and more than 10 million people worldwide are living with PD. Incidence of Parkinson’s disease increases with age, but an estimated four percent of people with PD are diagnosed before the age 50 [2]. The combined direct and indirect cost of Parkinson’s, including treatment, social security payments and lost income, is estimated to be nearly $25 billion per year in the United States alone [2].

The disease is typically characterized by movement abnormalities that develop with the progression of the disease. Freezing of Gait (FoG) is a movement abnormality associated with PD that presents in more advanced stages of the disease and is one of the most debilitating symptoms of PD. Persons affected by FoG refer to it as if his/her feet are glued to the ground, rendering the person unable to initiate or continue walking. FoG can typically be triggered by gait initiation, turning during walking or walking in restricted spaces (doorways etc.)

It is estimated that between one-half and one-third of PwPs experience FoG [3][4].

FoG is strongly associated with increased falls risk and it can significantly affect the PwP’s independence and quality of life by reducing their mobility.

FoG is widely perceived by clinicians as difficult to manage and the most challenging type of FoG to manage is ON-state FoG, which refers to the case when the PwP experiences FoG while they are getting the full benefits of their dopaminergic medication. ON-state FoG can occur either as a resistance to the otherwise positive effects of dopaminergic medication or in some cases, can be induced by the dopaminergic medication itself. These features of ON-state FoG make it particularly complex to manage through pharmacological interventions and hence the need for the development of novel, non-pharmacological treatments [5].

As FoG does not characteristically respond to medication changes, the mainstay of management is through cueing to try to prevent/relieve the freezing episode, however the techniques commonly used have functional limitations [6]. Cueing can be defined as using:

  • Internal stimuli which focus the PwP’s attention on the tasks of stepping and walking.
  • External stimuli which provides temporal (related to time) or spatial (related to space) information

to facilitate movement (gait) initiation and continuation [7].

Attentional strategies (internal stimuli) are the first line of choice for cueing and these involve thinking about the movement, such as thinking about placing the heel down first when walking or thinking about lifting the knees high (marching) when turning. Understandably, these techniques can be exhausting, and PwPs often struggle to use these when tired, distracted, or in a busy setting [6].

Visual cues are often the second line of treatment and involve taping lines on the floor at trigger points, for example doorways. This provides a trigger for the patient to step on or over the lines, thus improving gait. However, this technique is of no use outside the patient’s own environment. Laser sticks can be useful, but are expensive and require the patient to look at the floor with each step, which can increase falls risk, and contribute to secondary complications such as poor posture [6].

Auditory cues are generally the third option and involve the use of a metronome. This is set at a specific cadence for the PwP and they are advised to step in time to the beat. In this instance, a continuous beat plays, therefore it is not real-time cueing, and not sympathetic to normal stops and changes of pace. Furthermore, it can be irritating for the patient, and they are often unwilling to use it in a public place due to embarrassment. Earpieces can be used, but hearing difficulties often make this impossible [6].

In light of these limitations of conventional cueing techniques, the team at NUI Galway believes that there is an un-met need for a more user-friendly device that allows for effective real-time cueing for PwPs in their lived environment, in the broadest sense of the word and which evokes a positive user experience for the PwP.

To address this need, Professor Gearóid Ó Laighin, Dr. Leo Quinlan and Dean Sweeney, at the Human Movement Laboratory in the CÚRAM Centre for Research in Medical Devices at NUI Galway, developed ‘cueStim’, designed to prevent or relieve FoG using electronic means. The patented cueStim device uses sensory electrical stimulation (through skin-surface stimulation electrodes) to provide a cue to the sensory nervous system of the person with Parkinson’s (PwP). The electronic device, designed to be worn around the waist or in a pocket, was developed with funding from the European Union Framework 7 project (REMPARK project number CT-287677) and the Science Foundation Ireland TIDA programme (grant number 13RC2073).

The research collaboration between NUI Galway in Galway, Ireland and the National Health Service (NHS) Greater Glasgow and Clyde (NHSGGC) health system in Glasgow, Scotland found that when cueStim delivered ‘fixed’ rhythmic sensory electrical stimulation, there was a significant reduction in the time taken for a PwP to complete a home-based walking task and there was a significant reduction in the number of FoG episodes which occurred during that walking task. As a consequence, the PwP was able to walk more effectively and efficiently when using cueStim. The detailed findings of the study were published in the Journal of Healthcare Engineering.

NUI Galway Co-investigator, Dr. Leo Quinlan, from Physiology in the School of Medicine at NUI Galway, said: “These results are very encouraging as they show that cueStim reduced Freezing of Gait episodes and the time to complete a walking task in an independent clinical assessment with a pilot home-based study carried out by NHSGGC.”

The clinical study was designed by Dr Anne-Louise Cunnington, Consultant Geriatrician and Ms Lois Rosenthal, Movement Disorder Specialist and Highly Specialised Physiotherapist, both from NHSGGC.

Ms Lois Rosenthal, NHSGGC, said: “Freezing of gait is one of the most frustrating and difficult symptoms for patients to suffer and specialists to treat. This common feature of Parkinson’s is not improved by Parkinson’s medications, and is inconsistently responsive to cueing techniques trialled by physiotherapists. This collaboration between NUI Galway and NHSGGC explored a novel intervention and results were very encouraging. We now need a larger scale study to further evaluate effectiveness and real-life practicality.”

NUI Galway are now looking for partners to comprehensively test cueStim in a large-scale, home-based study.

Professor Gearóid Ó Laighin, said: “We are now seeking additional clinical partners to work with NUI Galway in carrying out a comprehensive long-term clinical evaluation of cueStim in enhancing the quality of life of people with Parkinson’s disease through a funded programme of research.”


[1]      P. Andlin-Sobocki, B. Jönsson, H. U. Wittchen, and J. Olesen, “Cost of disorders of the brain in Europe,” Eur. J. Neurol., vol. 12, no. S1, pp. 1–27, 2005.

[2]       “Statistics,” Parkinson’s Foundation, 13-Oct-2017. [Online]. Available: [Accessed: 05-Mar-2019].

[3]       N. Giladi and D. McMahon, “Motor blocks in Parkinson’s disease,” Neurology, vol. 42, pp. 333–339, 1992.

[4]       S. Fahn, “The Freezing Phenomenon in Parkinsonism,” Adv. Neurol., vol. 67, pp. 53–63, 1995.

[5]       L. Rosenthal, D. Sweeney, A.-L. Cunnington, L. R. Quinlan, and G. ÓLaighin, “Sensory Electrical Stimulation Cueing May Reduce Freezing of Gait Episodes in Parkinson’s Disease,” Journal of Healthcare Engineering, 2018. [Online]. Available: [Accessed: 05-Mar-2019].

[6]       A.-L. Cunnington and L. Rosenthal, “Does Sensory Electrical Stimulation (sES) help relieve Freezing of Gait (FOG) in patients with Parkinson’s disease?,” NHS Greater Glasgow Clyde, Glasgow, Research Ethics Application, 2015.

[7]       A. Nieuwboer et al., “Cueing training in the home improves gait-related mobility in Parkinson’s disease: The RESCUE trial.,” J. Neurol. Neurosurg. Psychiatry, vol. 78, pp. 134–140, 2007.


To read the full study in the  Journal of Healthcare Engineering, visit: