Altered coordination strategies during upright stance and gait in teachers of the Alexander Technique

Deterioration in movement and posture often occurs with aging. Yet there may be approaches to movement training that can maintain posture and movement coordination patterns as we age. The Alexander Technique is a non-exercise-based approach that aims to improve everyday movement and posture by increasing awareness and modulating whole-body postural muscle activity. This study assessed whether nineteen 55–72-year-old Alexander Technique teachers showed different posture and movement coordination patterns than twenty age-matched controls during a standing and walking protocol using 3D inertial sensors. During upright stance, Alexander Technique teachers showed lower centroidal sway frequency at the ankle (p = .04) and lower normalized jerk at the sternum (p = .05) than controls. During gait, Alexander Technique teachers had more symmetrical gait cycles (p = .04), more symmetrical arm swing velocity (p = .01), greater arm swing velocity (p < .01), greater arm swing range of motion (p = .02), and lower range of acceleration of the torso in the frontal plane (p = .03) than controls. Smoother control of upright posture, more stable torso motion, and less restrained arm mobility suggest that Alexander Technique training may counter movement degradation that is found with aging. Results highlight the important balance between mobility and stability within the torso and limbs

Alexander Technique vs. Targeted Exercise for Neck Pain—A Preliminary Comparison

Background: Alexander technique private lessons have been shown to reduce chronic neck pain and are thought to work by different mechanisms than exercise. Group classes may also be effective and would be cost-effective. Design: A two-group pre-test/post-test design. Participants were assigned to either a general Alexander technique class or an exercise class designed to target neck pain. Both groups met over 5 weeks for two 60 min sessions/week. Participants: A total of 16 participants with chronic neck pain (aged 50+/−16 years) completed this study. Interventions: The Alexander class used awareness-building methods to teach participants to reduce habitual tension during everyday activities. The exercise class was based on physical therapy standard of care to strengthen neck and back muscles thought to be important for posture. Measures: We assessed neck pain/disability, pain self-efficacy, activation of the sternocleidomastoid muscles during the cranio-cervical flexion test, and posture while participants played a video game. Results: Both groups reported decreased neck pain/disability after the interventions. Sternocleidomastoid activation decreased only in the Alexander group. Conclusion: In this small preliminary study, Alexander classes were at least as effective as exercise classes in reducing neck pain and seemed to work via a different mechanism. Larger, multi-site studies are justified

Mobility and Upright Posture Are Associated with Different Aspects of Cognition in Older Adults

Objectives : Aging is associated with cognitive decline, including visuomotor and memory concerns, and with motor system changes, including gait slowing and stooped posture. We investigated the associations of visuomotor performance and episodic memory with motor system characteristics in healthy older adults. Methods : Neurologically healthy older adults ( N = 160, aged 50–89) completed a battery of cognitive and motor tasks. Cognitive variables were grouped by principal components analysis (PCA) into two components: visuomotor performance and verbal episodic memory. Our primary predictor variables were two aspects of motor function: timed-up-and-go (TUG) speed and neck angle. Additional predictor variables included demographic factors (age, sex and education) and indicators of physical fitness (body mass index/BMI and grip strength). All seven predictor variables were entered stepwise into a multiple regression model for each cognitive component. Results : Poor visuomotor performance was best predicted by a combination of advanced age, high BMI and slow TUG, whereas poor verbal memory performance was best predicted by a combination of advanced age, male sex, low education and acute neck angle. Conclusions : Upright posture and mobility were associated with different cognitive processes, suggesting different underlying neural mechanisms. These results provide the first evidence for a link between postural alignment and cognitive functioning in healthy older adults. Possible causal relationships are discussed

Keeping your balance while balancing a cylinder: interaction between postural and voluntary goals

The present study investigated whether postural responses are influenced by the stability constraint of a voluntary, manual task. We also examined how task constraint and first experience (the condition with which the participants started the experiment) influence the kinematic strategies used to simultaneously accomplish a postural response and a voluntary task. Twelve healthy, older adults were perturbed during standing, while holding a tray with a cylinder placed with the flat side down (low constraint, LC) or with the rolling, round side down (high constraint, HC). Central set changed according to the task constraint, as shown by a higher magnitude of both the gastrocnemius and tibialis anterior muscle activation bursts in the HC than in the LC condition. This increase in muscle activation was not reflected, however, in changes in the center of pressure or center of mass displacement. Task constraint influenced the peak shoulder flexion for the voluntary tray task but not the peak hip flexion for the postural task. In contrast, first experience influenced the peak hip flexion but not the peak shoulder flexion. These results suggest an interaction between two separate control mechanisms for automatic postural responses and voluntary stabilization tasks.NIH [R37AG006457, T32 AT002688, T32AG023477, F32HD070796]University of GroningenStichting Groninger Universiteitsfonds (GUF

The interaction of postural and voluntary strategies for stability in Parkinson's disease

de Lima-Pardini AC, Papegaaij S, Cohen RG, Teixeira LA, Smith BA, Horak FB. The interaction of postural and voluntary strategies for stability in Parkinson's disease. J Neurophysiol 108: 1244-1252, 2012. First published June 6, 2012; doi:10.1152/jn.00118.2012.-This study assessed the effects of stability constraints of a voluntary task on postural responses to an external perturbation in subjects with Parkinson's disease (PD) and healthy elderly participants. Eleven PD subjects and twelve control subjects were perturbed with backward surface translations while standing and performing two versions of a voluntary task: holding a tray with a cylinder placed with the flat side down [low constraint (LC)] or with the rolling, round side down [high constraint (HC)]. Participants performed alternating blocks of LC and HC trials. PD participants accomplished the voluntary task as well as control subjects, showing slower tray velocity in the HC condition compared with the LC condition. However, the latency of postural responses was longer in the HC condition only for control subjects. Control subjects presented different patterns of hip-shoulder coordination as a function of task constraint, whereas PD subjects had a relatively invariant pattern. Initiating the experiment with the HC task led to 1) decreased postural stability in PD subjects only and 2) reduced peak hip flexion in control subjects only. These results suggest that PD impairs the capacity to adapt postural responses to constraints imposed by a voluntary task.National Institute on Aging [R37-AG-006457]Brazilian National Council for Scientific and Technological Development [200321/2010-2

Functional Reorganization of the Locomotor Network in Parkinson Patients with Freezing of Gait

<div><p>Freezing of gait (FoG) is a transient inability to initiate or maintain stepping that often accompanies advanced Parkinson’s disease (PD) and significantly impairs mobility. The current study uses a multimodal neuroimaging approach to assess differences in the functional and structural locomotor neural network in PD patients with and without FoG and relates these findings to measures of FoG severity. Twenty-six PD patients and fifteen age-matched controls underwent resting-state functional magnetic resonance imaging and diffusion tensor imaging along with self-reported and clinical assessments of FoG. After stringent movement correction, fifteen PD patients and fourteen control participants were available for analysis. We assessed functional connectivity strength between the supplementary motor area (SMA) and the following locomotor hubs: 1) subthalamic nucleus (STN), 2) mesencephalic and 3) cerebellar locomotor region (MLR and CLR, respectively) within each hemisphere. Additionally, we quantified structural connectivity strength between locomotor hubs and assessed relationships with metrics of FoG. FoG+ patients showed greater functional connectivity between the SMA and bilateral MLR and between the SMA and left CLR compared to both FoG− and controls. Importantly, greater functional connectivity between the SMA and MLR was positively correlated with i) clinical, ii) self-reported and iii) objective ratings of freezing severity in FoG+, potentially reflecting a maladaptive neural compensation. The current findings demonstrate a re-organization of functional communication within the locomotor network in FoG+ patients whereby the higher-order motor cortex (SMA) responsible for gait initiation communicates with the MLR and CLR to a greater extent than in FoG− patients and controls. The observed pattern of altered connectivity in FoG+ may indicate a failed attempt by the CNS to compensate for the loss of connectivity between the STN and SMA and may reflect a loss of lower-order, automatic control of gait by the basal ganglia.</p></div

Locomotor hubs used as regions of interest for functional connectivity analysis.

<p>X = 7 is chosen for display as it is the only slice on which all ROIs have some overlap. Please refer to the Methods section for coordinates describing the centroid of each sphere.</p

Patient characteristics.

<p>Significant differences (<i>P</i><0.05) between PD groups, assessed by Tukey’s HSD test, are highlighted in bold. All data displayed are mean (± standard deviation). HC = healthy controls. R = right, L = left, E = equal. ST = single task, DT =  dual task condition.</p

Associations between locomotor network functional connectivity and freezing severity.

<p><b>A)</b> Functional connectivity strength of the lMLR – SMA loop was positively correlated with clinical rating of FoG severity during the single task turning condition (r = 0.71). <b>B)</b> Functional connectivity strength of the rMLR – SMA loop was also positively correlated with objective sensor measurement of FoG severity during dual-task turning (0.76).</p