Elsevier

Gait & Posture

Volume 41, Issue 2, February 2015, Pages 630-633
Gait & Posture

Can sensory attention focused exercise facilitate the utilization of proprioception for improved balance control in PD?

https://doi.org/10.1016/j.gaitpost.2015.01.013Get rights and content

Highlights

  • Sensory attention focused exercise facilitates use of proprioceptive information.

  • Restricting vision during exercise helps to overcome vision dependence in PD.

  • Facilitating use of proprioceptive feedback translates to improved balance in PD.

  • PD SAFEx™ improves balance, a symptom that is poorly responsive to drug therapy.

Abstract

Impaired sensory processing in Parkinson's disease (PD) has been argued to contribute to balance deficits. Exercises aimed at improving sensory feedback and body awareness have the potential to ameliorate balance deficits in PD. Recently, PD SAFEx™, a sensory and attention focused rehabilitation program, has been shown to improve motor deficits in PD, although balance control has never been evaluated. The objective of this study was to measure the effects of PD SAFEx™ on balance control in PD. Twenty-one participants with mild to moderate idiopathic PD completed 12 weeks of PD SAFEx™ training (three times/week) in a group setting. Prior to training, participants completed a pre-assessment evaluating balance in accordance with an objective, computerized test of balance (modified clinical test of sensory integration and balance (m-CTSIB) and postural stability testing (PST)) protocols. The m-CTSIB was our primary outcome measure, which allowed assessment of balance in both eyes open and closed conditions, thus enabling evaluation of specific sensory contributions to balance improvement. At post-test, a significant interaction between time of assessment and vision condition (p = .014) demonstrated that all participants significantly improved balance control, specifically when eyes were closed. Balance control did not change from pre to post with eyes open. These results provide evidence that PD SAFEx™ is effective at improving the ability to utilize proprioceptive information, resulting in improved balance control in the absence of vision. Enhancing the ability to utilize proprioception for individuals with PD is an important intermediary to improving balance deficits.

Introduction

Impairments in sensory integration have been suggested to have an influence on motor symptoms and specifically balance control in Parkinson's disease (PD) [1], [2], [3], [4]. Interestingly, balance control deficits are exacerbated in dark environments or with eyes closed, suggesting that deficits in proprioception become an important factor that contribute to balance impairment in PD [5]. Given that postural instability becomes an increasing concern with disease progression, and is poorly responsive to drug therapies [2], [6], there is a need to identify alternative therapeutic interventions.

Therapeutic alternatives to pharmaceutical treatment in the form of physical activity and exercise have demonstrated additional benefits for motor symptoms in PD [7]. For example, treadmill training has shown improvements in gait parameters, such as stride length [8] and step variability [9]. It has been suggested that enhancing the utilization of intrinsic sensory feedback while exercising might alter cortical function through the release of neurotrophic factors or neurotransmitters [10]. The release of dopamine and neurotrophic factors in PD has been suggested to contribute to neural plasticity and repair [10]. Recognizing the benefits of sensory information during exercise, the PD SAFEx™ program was developed to promote the utilization of proprioceptive information in PD.

Given that balance control is heavily dependent on sensory inputs, if PD SAFEx™ is in fact increasing the utilization of proprioception, then a consequent improvement in balance control should be expected. Previous studies have demonstrated the effectiveness of the PD SAFEx™ program at improving motor symptoms by demonstrating a 25% improvement in Unified Parkinson's Disease Rating Scale (UPDRS) scores immediately following 12 weeks of training, with improvements persisting for a 6 week non-exercise period [11]. The program has also been shown to have increased benefits in motor symptom management when compared to lower limb aerobic exercise [12]. Interestingly, the ability of the PD SAFEx™ intervention to improve balance control has not yet been determined.

It was suggested by Sage and Almeida [12] that the underlying mechanism of PD SAFEx™ was plasticity driven, such that cortical changes might allow for incoming sensory information to develop a pathway to avoid the dysfunctional basal ganglia. This group alternatively suggested that the sensory load created by the program might act as a sufficient enough challenge to the basal ganglia that it might enhance the ability of the remaining dopaminergic neurons to aid in sensory processing [11], [12]. The benefits of PD SAFEx™ are widespread; however, the program has never been formally assessed for the ability of the program to specifically improve the use of sensory feedback in the absence of vision.

Thus, the aim of this study was to determine whether PD SAFEx™ can improve balance control with eyes open and eyes closed in PD. It was hypothesized that the PD SAFEx™ intervention would be successful at improving the utilization of proprioception, which would be detected through improved sway scores in the eyes closed balance condition. Since visual inputs would remain the dominant sensory resource when available, it was anticipated that improved proprioception might not have an effect on balance in the eyes open conditions. New outcome measures of exercise programs are a valuable means to providing better insight into some of the benefits associated with exercise, and the systems being targeted by the specific program.

Section snippets

Participants

This study was approved by the research ethics board at Wilfrid Laurier University, and all participants engaged following informed consent. Twenty-eight participants with idiopathic PD were randomly selected from the Sun Life Financial Movement Disorders Research and Rehabilitation Centre (MDRC), Waterloo, Ontario database and examined in this study. All participants were clinically diagnosed with PD, and had no other neurological deficits which would alter their ability to exercise safely. To

m-CTSIB

A significant interaction was found between time of assessment and vision (F(1,21) = 7.12, p = .014), Fig. 1. Post hoc analysis revealed significant improvement in balance scores during the eyes closed conditions only. Specifically, participants’ sway index improved by 12.7% from pre- to post-assessment (p = .0018).

There was also a significant main effect of surface (F(1,21) = 148.27, p < .001) such that the dynamic foam surface produced the poorest scores for balance control. Additionally, a significant

Discussion

The main finding of this study was that the PD SAFEx™ program significantly improved balance control only in the absence of vision, and hence, the ability of individuals with PD to utilize proprioceptive information. Given that proprioception is the predominant source of sensory information when the eyes are closed, improved balance control without vision can be argued to be the result of improvements in proprioceptive abilities. This can be inferred through improved sway scores in the eyes

Acknowledgements

This study was supported in part by a Parkinson's Disease Foundation Summer Student Fellowship, PDF-SFW-1476 to Shannon Lefaivre and Canada Foundation for Innovation to Quincy Almeida.

Conflict of interest: None to report.

Cited by (22)

  • The effects of a 12-week yoga intervention on body awareness in people with multiple sclerosis: A non-controlled pilot study

    2022, Advances in Integrative Medicine
    Citation Excerpt :

    The concept of interoception in relation to MS has been described in several publications; alterations in the sensing of bodily signals is prevalent among PwMS, indicating distinctively impaired interoceptive processes within this patient group [31–34]. Alterations related to sensing of bodily signals also characterizes related disorders such as Parkinson's disease [35–39], Tourette Syndrome [40] and Alzheimer's [41]. As the sensing of bodily signals is important as a tool to continuously assess possible effects and adverse effects of treatments, impaired interoceptive processes may constitute a barrier to finding optimal treatment strategies – in dialog with HCPs as well as self-initiated in daily life - among PwMS.

  • Use of real-time multimodal sensory feedback home program improved backward stride and retention for people with Parkinson Disease: A pilot study

    2022, Clinical Parkinsonism and Related Disorders
    Citation Excerpt :

    Sensory input, other than auditory feedback, is often neglected during intervention but recent shifts in rehabilitative training which enhance sensory input hold promise for pwPD. Programs such as PD SAFEx [15], a sensory and attention focused rehabilitation program as well as blindfolded balance training emphasize sensory training and report positive improvements in both motor and balance deficits [16]. Shen [17] used more traditional verbal and summary feedback (percentage of correct fast stepping and perturbation responses) for pwPD and found significant differences in stride length at 3 and 12 months after completing intense training compared to a program without feedback.

  • Linking anxiety, cognitive and sensory deficits to gait and balance deficits in Parkinson’s disease

    2020, Genetics, Neurology, Behavior, and Diet in Parkinson’s Disease: The Neuroscience of Parkinson’s Disease, Volume 2
  • Sensory training with vibration-induced kinesthetic illusions improves proprioceptive integration in patients with Parkinson's disease

    2017, Journal of the Neurological Sciences
    Citation Excerpt :

    These results signify that proprioceptive training changed the processing of proprioceptive inputs in PD patients. Previous studies have showed clinical and functional benefits in PD patients following a rehabilitation program, designed to have participants focus on proprioceptive feedback during physical exercises [27–29]. In these previous findings, the use of proprioceptive cues was reinforced by asking the participants to keep their eyes closed and to focus attention on specific portions of actual exercises.

View all citing articles on Scopus
View full text