Most of us don’t think twice about walking. It’s natural, something we’ve been doing since we were babies.
But what if suddenly, you couldn’t move your feet or take normal steps? Most of us wouldn’t know what to do.
As scary as it is, roughly 10 Million people with Parkinson’s across the world go through this every day. The complications caused by this condition can make any walk, whether to the kitchen or the corner store, difficult and frustrating.
As symptoms progress, many are at risk of injury and loss of personal independence, hurting both their physical and emotional health.
However, there is hope!
Research over the past 30 years has found that cues can complement medical treatment and physical activity for those diagnosed with Parkinson’s. With these now-popular techniques, it is possible to help people with Parkinson’s walk again.
How Parkinson’s Affects Walking
The likeliest cause of Parkinson’s is death of cells inside the basal ganglia, a region of the brain that helps direct bodily movement. The damage is primarily within the region called the substantia nigra” which produces dopamine, a neurotransmitter needed for movement. As the dopamine supply in the body goes down, the brain struggles to transmit neural impulses to the rest of the body.
This damage to the basal ganglia causes compromised motor functions, especially in the legs. The main walking related symptoms include small, shuffling steps (Parkinsonian Gait), involuntary increases in pace (festination) and freezing episodes (Freezing of Gait). Combined, these symptoms make walking incredibly dangerous, with current figures estimating that 70% of people with Parkinson’s will fall at least once, putting them at serious risk for injuries.
Research shows that damage to the basal ganglia caused by Parkinson’s is not evenly distributed, primarily affecting areas controlling automatic and habitual behavior, as opposed to goal-based movements. This discovery heavily suggests that in order to regain mobility, people with Parkinson's can consciously direct their body into movement.
It is this important insight that allows cueing technology to provide important assistance.
How Cues Work
Within Parkinson’s treatment, cues act as controlled external stimuli designed to improve a subject’s motor symptoms. By applying these signals, a person with Parkinsons’ can improve their overall gait patterns, using direct pathways connected to the premotor cortical system within the brain, bypassing the basal ganglia altogether.
The most common forms of cues consist of auditory and visual signals that engage sight and hearing to help improve movement. Other, less utilized forms can involve tactile sensations such as vibrations. Within these categories, cues belong to one of two types: 1) Open loop, pre-set mechanisms that act as a metric for movement and 2) closed loop, mechanisms that respond to a subject’s movement in real time, providing instant feedback.
With regular cue-based training, subjects can learn how to both prevent and manage freezing episodes, as well as other Parkinson’s symptoms. This ability is particularly important to the roughly 50% of people with Parkinson’s who experience Freezing of Gait on a regular basis.
Audio cues activate motor neurons that connect the brain to the spinal cord, and assist enhanced voluntary movement. These signals are usually delivered through rhythmic auditory stimulation using sounds including metronomes, music, verbal instructions or pre-recorded stepping patterns. As a subject listens to the auditory cues, they are able to time their footsteps and maintain a consistent pace.
Visual cues trigger motor pathways linked to the cerebellum to increase a subject’s range of motion. These signals provided on the floor, which can be laser projections or physical markers made of tape, act as targets for ideal step length. As a subject monitors the targets, they are able to manually plan the needed length of their steps, generating an optimal pattern of gait.
Effects of Cues
By reducing the need for internal timing mechanisms, cueing has proven to be an effective aid for people with Parkinson’s. One particular group that benefits from this treatment are those prone to freezing of Gait. The use of both visual and auditory cues reduce freezing episodes and improve their overall walking patterns, allowing them to avoid dangerous falls.
However, while both forms of cues improve gait patterns, they tend to yield different results.
Tests utilizing auditory cues exhibit increase in subject step length and speed, as well as accompanying arm movement. At the same time, most subjects in tests utilizing visual cues showed consistent step symmetry.
Most tests that combine auditory and visual cues show only a slight improvement over those with one focus or another. However, the addition of heavy physical activity to combined-cue tests, such as treadmill training, increases their effectiveness.
The effectiveness of cue-based treatments have led it to become a key facet of many Parkinson’s treatment regimens. However, since each person with Parkinson's has unique needs, it’s important to consult a physician to find a cue-based treatment that works best for each individual
1. Compensation Strategies for Gait Impairments in Parkinson Disease: A Review JAMA Neurology, March 2019 • 2. Cueing Paradigms to Improve Gait and Posture in Parkinson’s Disease: A Narrative Review • 3. Cueing Paradigms to Improve Gait and Posture in Parkinson’s Disease: A Narrative Review • 4. Predictors of freezing in Parkinson's disease: a survey of 6,620 patients, Mov Disord. May, 2007 • 5. Cueing Paradigms to Improve Gait and Posture in Parkinson’s Disease: A Narrative Review • 6. Acute and Chronic Effect of Acoustic and Visual Cues on Gait Training in Parkinson's Disease: A Randomized, Controlled Study • 7. Cueing for people with Parkinson's disease with freezing of gait: A narrative review of the state-of-the-art and novel perspectives • 8. Rehabilitation Treatment of Gait in Patients with Parkinson’s Disease with Freezing: A Comparison Between Two Physical Therapy Protocols Using Visual and Auditory Cues with or Without Treadmill Training