Rhythmic Auditory Cueing Research Articles

Step-to-step variability in treadmill walking: influence of rhythmic auditory cueing.

While walking, human beings continuously adjust step length (SpL), step time (SpT), step speed (SpS = SpL/SpT) and step width (SpW) by integrating both feedforward and feedback mechanisms. These motor control processes result in correlations of gait parameters between consecutive strides (statistical persistence). Constraining gait with a speed cue (treadmill) and/or a rhythmic auditory cue (metronome), modifies the statistical persistence to anti-persistence. The objective was to analyze whether the combined effect of treadmill and rhythmic auditory cueing (RAC) modified not only statistical persistence, but also fluctuation magnitude (standard deviation, SD), and stationarity of SpL, SpT, SpS and SpW. Twenty healthy subjects performed 6×5 min. walking tests at various imposed speeds on a treadmill instrumented with foot-pressure sensors. Freely-chosen walking cadences were assessed during the first three trials, and then imposed accordingly in the last trials with a metronome. Fluctuation magnitude (SD) of SpT, SpL, SpS and SpW was assessed, as well as NonStationarity Index (NSI), which estimates the dispersion of local means in the times series (SD of 20 local means over 10 steps). No effect of RAC on fluctuation magnitude (SD) was observed. SpW was not modified by RAC, what is likely the evidence that lateral foot placement is separately regulated. Stationarity (NSI) was modified by RAC in the same manner as persistent pattern: Treadmill induced low NSI in the time series of SpS, and high NSI in SpT and SpL. On the contrary, SpT, SpL and SpS exhibited low NSI under RAC condition. We used relatively short sample of consecutive strides (100) as compared to the usual number of strides required to analyze fluctuation dynamics (200 to 1000 strides). Therefore, the responsiveness of stationarity measure (NSI) to cued walking opens the perspective to perform short walking tests that would be adapted to patients with a reduced gait perimeter.

Music and metronome cues produce different effects on gait spatiotemporal measures but not gait variability in healthy older adults

Rhythmic auditory cues including music and metronome beats have been used, sometimes interchangeably, to improve disordered gait arising from a range of clinical conditions. There has been limited investigation into whether there are optimal cue types. Different cue types have produced inconsistent effects across groups which differed in both age and clinical condition. The possible effect of normal ageing on response to different cue types has not been reported for gait. The aim of this study was to determine the effects of both rhythmic music and metronome cues on gait spatiotemporal measures (including variability) in healthy older people. Twelve women and seven men (>65 years) walked on an instrumented walkway at comfortable pace and then in time to each of rhythmic music and metronome cues at comfortable pace stepping frequency. Music but not metronome cues produced a significant increase in group mean gait velocity of 4.6cm/s, due mostly to a significant increase in group mean stride length of 3.1cm. Both cue types produced a significant but small increase in cadence of 1step/min. Mean spatio-temporal variability was low at baseline and did not increase with either cue type suggesting cues did not disrupt gait timing. Study findings suggest music and metronome cues may not be used interchangeably and cue type as well as frequency should be considered when evaluating effects of rhythmic auditory cueing on gait. Further work is required to determine whether optimal cue types and frequencies to improve walking in different clinical groups can be identified.

Persistent and anti-persistent pattern in stride-to-stride variability of treadmill walking: Influence of rhythmic auditory cueing

Abstract It has been observed that long time series of Stride Time (ST), Stride Length (SL) and Stride Speed (SS = SL/ST) exhibited statistical persistence (long-range auto-correlation) in overground walking. Rhythmic auditory cueing induced anti-persistent (or anti-correlated) patterns in ST series, while SL and SS remained persistent. On the other hand, it has been shown that SS became anti-persistent in treadmill walking, while ST and SL remained persistent. The aim of this study was to analyze the effect of the combination of treadmill walking (imposed speed) and auditory cueing (imposed cadence) on gait dynamics. Twenty middle-aged subjects performed 6 × 5 min walking trials at various imposed speeds on an instrumented treadmill. Freely chosen walking cadences were measured during the first three trials, and then imposed accordingly in the last three trials by using a metronome. Detrended fluctuation analysis (DFA) was performed on the times series of ST, SL, and SS. Treadmill induced anti-persistent dynamics in the time series of SS, but preserved the persistence of ST and SL. On the contrary, all the three parameters were anti-persistent under dual-constraints condition. Anti-persistent dynamics may be related to a tighter control: deviations are followed by a rapid over-correction, which produces oscillations around target values. Under single constraint condition, while SS is tightly regulated in order to follow the treadmill speed, redundancy between ST and SL would likely allow persistent pattern to occur. Conversely, under dual constraint conditions, the absence of redundancy among SL, ST and SS would explain the generalized anti-persistent pattern.

Comparing the effects of rhythmic auditory cueing and visual cueing in acute hemiparetic stroke

Introduction: Every individual requires proper upper limb functions as well as proper walking balance to meet day-to-day demands. Some of the most common problems faced after stroke are balance problems, which, in turn affect the recovery of activities of daily living (ADL), mobility, and lead to an increased risk of falls. In addition, about 80% of all stroke survivors have an upper limb paresis immediately after stroke affecting gross motor and fine motor problems. Objective: To evaluate the effectiveness of rhythmic auditory stimulation and conventional treatment on gross motor, fine motor activities, and walking imbalance; to evaluate the effectiveness of visual cues and conventional treatment on gross motor, fine motor activities, and walking imbalance; and to compare the effectiveness of rhythmic auditory stimulation and visual cueing with conventional treatment on gross motor, fine motor activities, and walking imbalance. Methodology: Design-a randomised controlled trial of 45 participants in acute stage were recruited. The subjects selected for the study were randomly allocated using sealed envelopes into three groups Group A-rhythmic auditory stimulation and conventional treatment, Group B-visual cueing and conventional treatment, Group C-conventional treatment. Outcome measures: Dynamic gait index and upper extremity Fugl Meyer motor score. Result: After one month of therapy a comparison of the groups showed a statistically significant improvement in all three groups independently (P=<0.05 in Group A, B, and C). On comparing post scores between the groups, a statistically significant difference was found between group A and C, and group B and C data (P=<0.05). Conclusion: Both the therapies were effective for gross motor, fine motor, and gait imbalance in acute hemiparetic stroke.

Making music after stroke: using musical activities to enhance arm function

A common long-term consequence of stroke is impaired arm function, which affects independence and quality of life in a considerable proportion of stroke survivors. There is a growing need for self-management strategies that enable stroke survivors to continue their recovery after rehabilitation has ceased. Interventions with high-intensity, repetitive task training and feedback are most likely to improve function. Achieving the required amount of self-practice is challenging, however. Innovative approaches are required to translate therapies into rewarding activities that can be undertaken independently. This paper describes the key principles and development of a novel intervention that integrates individuals' preferred music with game technology in upper limb rehabilitation. The "tap tempo" paradigm, which uses rhythmic auditory cueing, provides repetitive upper limb task training, which can be tailored to individual goals and progress (e.g., in terms of movement range and complexity), while providing sensitive quantitative feedback to promote skill acquisition and enhance self-management.

The possible price of auditory cueing: Influence on obstacle avoidance in Parkinson's disease

Under carefully controlled conditions, rhythmic auditory cueing can improve gait in patients with Parkinson's disease (PD). In complex environments, attention paid to cueing might adversely affect gait, for example when a simultaneous task-such as avoiding obstacles-has to be executed. We primarily examined whether concurrent auditory cueing interferes with an obstacle avoidance task in patients with PD. The secondary aim was to study differences between patients with and without freezing of gait. Nineteen patients with PD (8 with freezing) were examined on a treadmill in 4 conditions: normal walking; walking with auditory cueing; walking with an obstacle avoidance task; and walking with auditory cueing and obstacle avoidance. Outcome measures included kinematic gait parameters and obstacle crossing parameters. Auditory cueing improved gait in PD, without negative effects on concurrent obstacle avoidance. Additionally, freezers avoided obstacles less efficiently than non-freezers. PD patients are able to successfully execute an obstacle avoidance task, when auditory cueing is administered simultaneously. The different obstacle avoidance behavior in freezers may contribute to their higher fall risk.

1.229 QUANTITATIVE ASSESSMENT OF REST AND ACTION TREMOR AND THE EFFECT OF CUEING IN PARKINSON'S PATIENTS TREATED WITH DEEP BRAIN STIMULATION

Introduction: In Parkinson’s disease rest and action tremor may occur. High frequency deep brain stimulation in basal ganglia nuclei has proved to be effective in the suppression of tremor. In addition, rhythmic auditory cues have shown to result in improved performance of repetitive movements, possibly by suppressing action tremor. The aim of this study was to investigate if electrical stimulation has similar effects on rest and action tremor, and whether in case of action tremor, the effect of electrical stimulation is similar to or enhanced by auditory cueing. Methods: Three exercises were carried out by 7 Parkinson’s disease patients treated with deep brain stimulation of the subthalamic nucleus: 1) sitting at rest; 2) performing a hand tapping movement as fast as possible; 3) performing hand movements on the rhythm of an auditory cueing signal. Inertial sensors registered the movement of the hands during the tests. The exercises were repeated for four different stimulation settings. Results: Electrical stimulation may either enhance or suppress rest and/or action tremor. Power spectral density analysis shows that tremor suppression is accompanied by an increase in relative power in the low frequency band for both rest and action tremor. Most patients could (temporarily) phase lock their hand movements to the cueing signal of 1.6 Hz. Cueing signals at higher frequencies (3.2 and 4.8 Hz) could result in (n:m) phase locking of tremor as well as movement. Conclusion: Electrical stimulation results in a re-scaling of tremor, while auditory cueing may enhance suppression.

The Effects of Therapeutic Instrumental Music Performance on Endurance Level, Self-Perceived Fatigue Level, and Self-Perceived Exertion of Inpatients in Physical Rehabilitation

The present study investigated the effects of a Neurologic Music Therapy (NMT) sensory-motor rehabilitation technique, Therapeutic Instrumental Music Performance (TIMP) as compared to Traditional Occupational Therapy (TOT), on endurance, self-perceived fatigue, and self-perceived exertion of 35 hospitalized patients in physical rehabilitation. The present study attempted to examine whether an active musical experience such as TIMP with musical cueing (i.e., rhythmic auditory cueing) during physical exercises influences one's perception of pain, fatigue, and exertion. All participants were diagnosed with a neurologic disorder or had recently undergone orthopedic surgery. Investigators measured the effects of TOT and TIMP during upper extremity exercise of the less affected or stronger upper extremity. Results showed no significant difference on endurance measures between the 2 treatment conditions (TIMP and TOT). Statistically significant differences were found between TIMP and TOT when measuring their effects on perceived exertion and perceived fatigue. TIMP resulted in significantly less perception of fatigue and exertion levels than TOT. TIMP can be used foran effective sensory-motor rehabilitation technique to decrease perceived exertion and fatigue level of inpatients in physical rehabilitation.

Shared mechanisms in perception and imagery of auditory accents

Objective An auditory rhythm can be perceived as a sequence of accented (loud) and non-accented (soft) beats or it can be imagined. Subjective rhythmization refers to the induction of accenting patterns during the presentation of identical auditory pulses at an isochronous rate. It can be an automatic process, but it can also be voluntarily controlled. We investigated whether imagined accents can be decoded from brain signals on a single-trial basis, and if there is information shared between perception and imagery in the contrast of accents and non-accents. Methods Ten subjects perceived and imagined three different metric patterns (two-, three-, and four-beat) superimposed on a steady metronome while electroencephalography (EEG) measurements were made. Shared information between perception and imagery EEG is investigated by means of principal component analysis and by means of single-trial classification. Results Classification of accented from non-accented beats was possible with an average accuracy of 70% for perception and 61% for imagery data. Cross-condition classification yielded significant performance above chance level for a classifier trained on perception and tested on imagery data (up to 66%), and vice versa (up to 60%). Conclusions Results show that detection of imagined accents is possible and reveal similarity in brain signatures relevant to distinction of accents from non-accents in perception and imagery. Significance Our results support the idea of shared mechanisms in perception and imagery for auditory processing. This is relevant for a number of clinical settings, most notably by elucidating the basic mechanisms of rhythmic auditory cuing paradigms, e.g. as used in motor rehabilitation or therapy for Parkinson’s disease. As a novel Brain–Computer Interface (BCI) paradigm, our results imply a reduction of the necessary BCI training in healthy subjects and in patients.

The impact of attentional, auditory, and combined cues on walking during single and cognitive dual tasks in Parkinson disease

Auditory and attentional cues improve gait in Parkinson disease (PD), but it is unclear if combining the two cueing strategies offers additional benefit. Further, the effect of a secondary cognitive task on cue efficacy is unknown. Therefore, this study aimed to assess the effects of cue type and task complexity on gait in PD. 11 participants with PD, 11 age-matched controls, and 11 young controls performed 3 walking trials on a GAITRite walkway under the following cueing conditions: no cue (baseline), rhythmic auditory cue at 10% below (AUD−10) and 10% above (AUD+10) self selected cadence, attentional cue (ATT; “take long strides”), and a combination of AUD and ATT (COM−10, COM+10). Each condition was also performed concurrently with a secondary word generation task (dual task, DT). Baseline gait velocity and stride length were less for those with PD and age-matched controls compared to young controls, and the ability of those with PD to use cues differed from the other groups. Gait velocity and stride length increased in PD with ATT, but not with auditory cues. Similar increases in gait velocity and stride length were observed with the combined cues, but additional benefit beyond ATT alone was not observed. Cues did not improve gait velocity during dual task walking, although stride length did increase with COMB+10. It appears persons with PD are able to benefit from attentional cueing and can combine attentional and auditory cues, but do not gain additional benefit from such a combination. During walking while performing a secondary cognitive task, attentional cues may help to facilitate a longer stride length.

Mesencephalic Corticospinal Atrophy Predicts Baseline Deficit but Not Response to Unilateral or Bilateral Arm Training in Chronic Stroke

Objective. Stroke survivors with motor deficits often have pyramidal tract atrophy caused by degeneration of corticospinal fibers. The authors hypothesized that the degree of atrophy correlates with severity of motor impairment in patients with chronic stroke and predicts the response to rehabilitation training. Methods. They performed a post hoc analysis of 42 hemiparetic patients (>6 months) who had been randomized to either 6 weeks of bilateral arm training with rhythmic auditory cueing (BATRAC) or dose-matched therapeutic exercise (DMTE). Arm function was measured using the Fugl-Meyer (FM) and modified Wolf Motor Function Test (WMFT). Structural MRI and diffusion tensor imaging (DTI) on the pontine level measured corticospinal tract (CST) atrophy by planimetric measurement of the mesencephalon (mesencephalic atrophy ratio) and fractional anisotropy (FA), respectively. Voxel-based lesion symptom mapping (VLSM) was used to determine the lesions associated with highest degrees of atrophy. The predictive value of CST atrophy for impairment and training response was analyzed. Results. CST atrophy predicted baseline motor arm function measured by the FM and WMFT. The authors found only a trend for the correlation with FA. No measure of atrophy predicted response to either BATRAC or DMTE. CST atrophy was higher with larger lesions and those that affected the CST. VLSM identified internal capsule lesions as being associated with highest CST atrophy. Conclusion. Larger lesions, internal capsule lesions, and those overlapping the pyramidal tract are associated with greater CST atrophy. CST atrophy explains in part the variability of baseline deficits but does not seem to predict the response to BATRAC or unilateral arm training on upper-extremity function.

Bilateral and Unilateral Arm Training Improve Motor Function Through Differing Neuroplastic Mechanisms

Background and Purpose. This randomized controlled trial tests the efficacy of bilateral arm training with rhythmic auditory cueing (BATRAC) versus dose-matched therapeutic exercises (DMTEs) on upper-extremity (UE) function in stroke survivors and uses functional magnetic resonance imaging (fMRI) to examine effects on cortical reorganization. Methods. A total of 111 adults with chronic UE paresis were randomized to 6 weeks (3×/week) of BATRAC or DMTE. Primary end points of UE assessments of Fugl-Meyer UE Test (FM) and modified Wolf Motor Function Test Time (WT) were performed 6 weeks prior to and at baseline, after training, and 4 months later. Pretraining and posttraining, fMRI for UE movement was evaluated in 17 BATRAC and 21 DMTE participants. Results. The improvements in UE function (BATRAC: FM Δ = 1.1 + 0.5, P = .03; WT Δ = −2.6 + 0.8, P < .00; DMTE: FM Δ = 1.9 + 0.4, P < .00; WT Δ = −1.6 + 0.7; P = .04) were comparable between groups and retained after 4 months. Satisfaction was higher after BATRAC than DMTE (P = .003). BATRAC led to significantly higher increase in activation in ipsilesional precentral, anterior cingulate and postcentral gyri, and supplementary motor area and contralesional superior frontal gyrus (P < .05). Activation change in the latter was correlated with improvement in the WMFT (P = .01). Conclusions. BATRAC is not superior to DMTE, but both rehabilitation programs durably improve motor function for individuals with chronic UE hemiparesis and with varied deficit severity. Adaptations in brain activation are greater after BATRAC than DMTE, suggesting that given similar benefits to motor function, these therapies operate through different mechanisms.

Generalization of a modified form of repetitive rhythmic bilateral training in stroke

Objective To determine if a modified form of repetitive rhythmic bilateral training will generalize to two reach to target tasks. Setting Testing and training were performed at the Brain Rehabilitation Research Center, Malcom Randall VAMC in Gainesville, Florida. Subjects Fourteen subjects with chronic stroke completed this study: 9 male, 5 female, mean age 64.4 years, and a mean of 5.5 years post-stroke. Intervention Modified Bilateral Arm Training with Rhythmic Auditory Cueing (modBATRAC) was performed 4 sessions/week of 2.25 h/session for 2 weeks. Main measures End-point kinematic measures; hand path curvature, time to peak velocity, peak velocity, smoothness of the curve and acceleration using the Vicon motion analysis system during two reach to target tasks: (1) similar spatial demands (2) dissimilar spatial demands. An individual analysis was performed to investigate if there was any pattern of responding. Additionally, correlation analyses of kinematic and functional measures taken pre- and post-test were performed. Results Improvements were found at post-test for hand path curvature, smoothness of the curve, and peak velocity and were equivalent across two reach to target tasks. Discussion Generalization was found for both reach to target tasks for end-point kinematic aspects (PV, HPC, and number of Peaks) during modBATRAC training. There was a positive correlation with the significant kinematic variables (HPC and PV) and the functional measures used pre- and post-test in this study. This suggests that generalization may be possible through the practice of basic coordinated movements after stroke. These basic movements may provide the building blocks for more complex movement behaviors.

Temporal and spatial control following bilateral versus unilateral training

Principles of motor control and learning such as bilateral coordination and task-specificity, are increasingly incorporated in the design of upper extremity rehabilitation protocols for stroke survivors. Yet most studies investigating the efficacy of new protocols report composite scores of standardized tests, such as the Fugl-Meyer Upper Extremity test (FM) and the Wolf Motor Arm Test, rather than determining how the motor control and coordination of arm movements has changed. Here we present a sub-study of a larger randomized controlled trial comparing a bilateral and unilateral training protocol where participants were assessed on bilateral and unilateral arm reaching. Eligible participants for the arm reaching analysis were 9 (FM=37) and 9 (FM=34) in Bilateral Arm Training with Rhythmic Auditory Cueing (BATRAC) and Dose Matched Therapeutic Exercises (DMTE), respectively. Participants undertook 18 sessions of training for 6 weeks with 20min of active training per session. For bilateral arm reaching, participants after BATRAC were faster, with increased peak acceleration, fewer movement units, and smoother hand paths for each arm. The BATRAC training group showed greater improvements with training than the DMTE group during bilateral reaching for parameters of movement units and smoothness of hand path. For unilateral arm reaching, participants were faster after DMTE for paretic arm reaching; however, this group did not improve to a greater extent than the BATRAC training group. Within group functional gains were seen after BATRAC on FM, Wolf Motor Arm Test (time and weight) and after DMTE on FM and Wolf Weight. There was a positive correlation between movement units and the time component of the Wolf Motor Arm Test. The reaching analysis demonstrates task-specificity in training since BATRAC improves performance in bilateral reaching and DMTE improves performance in unilateral reaching. Temporal/spatial control outcomes in studies of post-stroke interventions can identify functionally relevant motor control changes that are not captured by traditional standardized tests.

Repetitive transcranial magnetic stimulation interrupts phase synchronization during rhythmic motor entrainment

Rhythmic stimuli delivered through the auditory system can facilitate improved motor control following a motor impairment. The synchronization of movement to rhythmic auditory cues is characterized by quick, stable coupling of motor responses to rhythmic auditory cues. The exact neural sites responsible for this transformation of auditory input into timed rhythmic motor output are not clear. Neuroimaging studies have identified left ventral premotor cortex (vPMC) and left superior temporal-parietal (STP) activation during rhythmic auditory-motor synchronization. To investigate brain areas necessary for different types of rhythmic auditory-motor synchronization, we delivered repetitive transcranial magnetic stimulation (rTMS) to 15 healthy individuals prior to a rhythmic-auditory tapping task. Subthreshold rTMS was administered separately to the left vPMC and STP at a frequency of 0.9Hz for 15 min. Phase synchronization error (difference between auditory stimulus and response onsets) significantly increased after rTMS to STP as compared to baseline. Synchronization error also increased after rTMS to vPMC as compared to baseline, but not significantly. Absolute period error, (absolute difference between metronome interval and response interval) was not affected by rTMS. The significant effect of rTMS at the STP expands upon previous imaging research, suggesting that this area is part of the network responsible for rhythmic auditory-motor synchronization. The effect of rTMS on phase synchronization, but not period synchronization suggests these are separate neural processes controlled by different neural networks.

The Immediate Effect of Attentional, Auditory, and a Combined Cue Strategy on Gait During Single and Dual Tasks in Parkinson’s Disease

Baker K, Rochester L, Nieuwboer A. The immediate effect of attentional, auditory, and a combined cue strategy on gait during single and dual tasks in Parkinson’s disease. Objective To compare the effect of rhythmic auditory and attentional cues, and a combination of both cues on gait, in people with Parkinson’s disease (PD) during single and dual tasks. Design A repeated-measures study requiring participants to perform single and dual-motor tasks under different cueing conditions. Setting Human movement analysis laboratory. Participants Fifteen participants with idiopathic PD and a comparison group of 12 healthy participants. Interventions Three cueing strategies were compared: a rhythmic auditory cue (walking in time to a metronome beat), an attentional strategy (asked to focus on taking big step), and a combination cue (asked to walk in time to a metronome beat while taking big steps). Main Outcome Measures Walking speed, step amplitude, and step frequency. Results Walking speed of PD participants improved significantly compared with noncued walking in the single- and dual-task condition with the attentional ( P<.001, P=.037) and combination cue strategies ( P=.013, P=.028). Step amplitude also increased significantly with the attentional and combination cue strategies in single- ( P<.001, P<.001) and dual-task ( P<.001, P<.001) conditions. Step frequency was reduced significantly with the attentional strategy ( P=.042) in the single and dual tasks ( P<.001) and combination cue strategy ( P=.009) in the dual task. The rhythmic auditory cue alone did not alter significantly any parameter of gait in the single or dual tasks. Conclusions The attentional strategy and the combination of a rhythmic auditory cue with an attentional strategy were equally effective, and improved walking speed and step amplitude significantly during both single and dual tasks. The combination cue, however, may still be a useful alternative in situations of increased attentional demand, or where problems exist with executive function.

Turning in Parkinson's disease patients and controls: The effect of auditory cues

Turning is an impaired activity in persons with Parkinson's disease (PwPD). The current study examines the turning characteristics in PwPD (9 freezers and 10 nonfreezers) and 9 controls, and explores the effect of rhythmic auditory cues while turning. Turning parameters were collected from a 180 degrees left U-turn during a noncued and a cued condition, using a 3D measuring system. Auditory cues were supplied with a metronome at a rhythm equaling the subject's comfortable step frequency during straight line walking. Results showed that in contrast to controls, PwPD used a wider turning-arc and took smaller, narrower steps. In addition, they demonstrated a higher Coefficient of Variation (CV) of step duration (6.92%) compared to controls (4.88%, P < 0.05). The "wide-arc" turning strategy of PwPD was more prominent in freezers than in nonfreezers. Auditory cues reduced the CV of step duration in PwPD (both freezers and nonfreezers) during turning (from 6.92 to 6.00%, P < 0.05). In summary: Cueing reduced the gait-timing variability during turning, but PwPD maintained a wider arc to turn compared with controls.

Bilateral Arm Training With Rhythmic Auditory Cueing in Chronic Stroke: Not Always Efficacious

Objective. Bilateral arm training with rhythmic auditory cueing (BATRAC) has been reported to be efficacious in promoting upper-extremity (UE) recovery in chronic stroke. We tested a modified form of BATRAC (modBATRAC) in a new group of participants with a condensed treatment regime to determine whether we could replicate these reported results. Methods. Fourteen subjects with chronic stroke completed 2 weeks of 2.25 hours per session, 4 sessions per week of modBATRAC. Results. No significant changes were observed in UE Fugl-Meyer or Wolf Motor Function Test scores. Subjects did report increased paretic UE use on the Motor Activity Log (mean change, 0.50; SD = 0.70). Conclusions. The results of this study offer only partial support for the efficacy of modBATRAC. As in previous trials, modBATRAC facilitated increased use of the paretic arm, but unlike previous trials, it did not increase motor performance. These differences may reflect a more temporally condensed training schedule and less impaired patients.

The effect of rhythmic somatosensory cueing on gait in patients with Parkinson's disease

Background and aims Gait and gait related activities in patients with Parkinson's disease (PD) can be improved with rhythmic auditory cueing (e.g. a metronome). In the context of a large European study, a portable prototype cueing device was developed to provide an alternative for rhythmic auditory cueing: rhythmic somatosensory cueing (RSC, a miniature vibrating cylinder attached to the wrist). We investigated whether PD patients could adapt their walking pattern using RSC under conditions of changing walking speed and the presence of potentially distracting visual flow while walking on a treadmill. Methods A total of 17 patients with PD participated (mean age 63.4 ± 10.3 years; Hoehn-Yahr score 2.5 ± 0.9, mean Unified Parkinson's Disease Rating Scale score 49.8 ± 13.7, mean disease duration 7.7 ± 5.1 years). They performed systematic walking speed manipulations under 4 conditions in a random order: (1) no cue, no visual flow, (2) no cue, visual flow, (3) cue, no visual flow and (4) cue, visual flow. Visual flow in the form of a virtual corridor that moved at the current walking speed was projected on a 2 × 2 m rear-projection screen. The cueing rhythm was set at − 10% of preferred stride frequency at each speed. Stride frequency was assessed using peaks in the trajectories of thigh sagittal plane segmental angles. Results Walking with RSC resulted in lower stride frequencies, and thus larger step lengths ( p-values < 0.05), regardless of walking speed. The presence of visual flow did not impair the use of RSC, as evidenced by the lack of differences between conditions 3 and 4 ( p > 0.05). Conclusion Rhythmic somatosensory cueing may be a viable alternative for auditory cueing and is robust to changes in walking speed and visual distractors.

Influence of visual cues on gait in Parkinson's disease: Contribution to attention or sensory dependence?

Sensory cueing is used for a long time to improve gait in patients with Parkinson's disease. This has been established for visual cues such as stripes on floor and for rhythmic auditory cues. Concerning visual cueing two main mechanisms of action have been suggested and may be suitable depending on the instruction given to the patients. Stripes placed on the walking surface may draw attention to the stepping process if patients are talked to put their feet on the stripes. In another paradigm, the stripes on floor are just used to enhance the optical flow and the motion of the stripes is essential to improve gait. These findings are not found in normal controls suggesting that patients with Parkinson's disease are more dependent on dynamic visual cues for gait control than controls. Several common characteristics exist between attention and sensory contribution in gait control. First, their potential beneficial effect may be contre-balanced by a negative influence: visual information may be helpful for gait in patients or may disrupt locomotion and induce freezing (for example passing a door). Attention focused on gait allows a partial correction of the troubles by intentional modulation of the stride length but a dual task flowing attention away produces deterioration. Another point is that both strategies are probably used by the central nervous system to compensate deficits: visual dependence to compensate an impaired kinesthetic feed-back and attentional processing to alleviate automaticity in locomotion and so, to by-pass the deficit of internal cueing.