This study identified and quantified rambling and trembling properties of the postural control system of children 4–12 years of age. Forty five children of varying ages (4-, 8-, and 12-years) and 15 adults stood upright on a force plate and performed 5 trials with and 5 trials without vision with each trial lasting 30 s. Center of pressure, rambling, trembling, mean sway amplitude, and predominant frequency were obtained. Results revealed that the displacement of the center of pressure and overall rambling trajectories were age-related with younger children swaying more than older children and adults. Similarly, overall trembling trajectories for younger children were larger compared with older children and adults. These results suggested that a younger child’s larger body sway mostly results from difficulties using sensory information when estimating overall body position and velocity in an upright stance and is less a result from the noise in the postural control system.
Priscilla Augusta Monteiro Ferronato and José Angelo Barela
Joan E. Deffeyes, Regina T. Harbourne, Wayne A. Stuberg and Nicholas Stergiou
Sitting is one of the first developmental milestones that an infant achieves. Thus measurements of sitting posture present an opportunity to assess sensorimotor development at a young age. Sitting postural sway data were collected using a force plate, and the data were used to train a neural network controller of a model of sitting posture. The trained networks were then probed for sensitivity to position, velocity, and acceleration information at various time delays. Infants with typical development developed a higher reliance on velocity information in control in the anterior-posterior axis, and used more types of information in control in the medial-lateral axis. Infants with delayed development, where the developmental delay was due to cerebral palsy for most of the infants in the study, did not develop this reliance on velocity information, and had less reliance on short latency control mechanisms compared with infants with typical development.
Julie Vaughan-Graham, Kara Patterson, Karl Zabjek and Cheryl A. Cott
gravity, task selection, and the environment ( Vaughan-Graham & Cott, 2016 ). The consideration of sensory information arising from alignment created by selective muscle activity and orientation of the body with -/respect to BOS and gravity, and thus, the role of body schema ( Vaughan-Graham & Cott, 2016
Beyond the trivial assumption that without a body we cannot gather sensory information from the environment and we cannot act upon it, our particular body, right here, right now, both enables and constrains our perception of the environment. In this review, I provide empirical support for the idea that our physical body can narrow the set of our possible interactions with the environment by shaping the way we perceive stimuli around us. I will propose that such effects are contributed by the effect of our physical body—that is, flesh and bone body—on the oscillatory dynamics of intrinsic brain activity.
David Antonio Gonzalez, Adam Dubrowski and Heather Carnahan
Visual and haptic integration has been examined extensively, however little is known about alternative premovement sensory information to help in the anticipatory control of prehension. This study explored the concept of using auditory cues as an alternative premovement cue. Individuals lifted champagne flutes filled with various levels of water; and one group was given a sound cue before lifting. Sounds provided a precue regarding fluid level and hence mass. Results showed that auditory cues were used to predict the “target force” required to lift the masses, as evidenced by scaling of grip rates as a function of mass in the auditory cue group only. It was hypothesized that individuals used the auditory cues to preprogram the grasping forces produced during the lifting movement.
Paula F. Polastri and and José A. Barela
This study examined the effects of experience and practice on the coupling between visual information and trunk sway in infants with Down syndrome (DS). Five experienced and five novice sitters were exposed to a moving room, which was oscillated at 0.2 and 0.5 Hz. Infants remained in a sitting position and data were collected on the first, fourth, and seventh days. On the first day, experienced sitters were more influenced by room oscillation than were novices. On the following days, however, the influence of room oscillation decreased for experienced but increased for novice sitters. These results suggest that the relationship between sensory information and motor action in infants with DS can be changed with experience and practice.
Frederik J.A. Deconinck, Dirk De Clercq, Rudy Van Coster, Ann Oostra, Griet Dewitte, Geert J.P. Savelsbergh, Dirk Cambier and Matthieu Lenoir
This study examined and compared the control of posture during bilateral stance in ten boys with Developmental Coordination Disorder (DCD) of 6-8 years old and ten matched typically developing boys in four sensory conditions (with or without vision, on a firm or complaint surface). In all conditions mean postural sway velocity was larger for the boys with DCD, in spite of a normal score on the balance items of the Movement Assessment Battery for Children. A Group X Condition interaction revealed a larger dependency on vision in the boys with DCD when standing on a firm surface. These results suggest that in this specific subgroup of boys with DCD with predominantly problems in fine motor and ball skills postural control problems may still be prevalent and may possibly be associated with difficulties to re-weight sensory information in response to environmental demands.
Sonia Julià-Sánchez, Jesús Álvarez-Herms, Hannes Gatterer, Martin Burtscher, Teresa Pagès and Ginés Viscor
Contradictory results are still reported on the influence of dental occlusion on the balance control. We attempted to determine whether there are differences in balance between opposed dental occlusion (Intercuspal position (ICP)/“Cotton rolls” mandibular position [CR]) for two extreme levels of stability (stable/unstable). Twenty-five subjects were monitored under both dental occlusion and level of stability conditions using an unstable platform Balance System SD. The resulting stability index suggests that body balance is significantly better when dental occlusion is set in CR (p < .001) in unstable but not in stable conditions. Occlusal traits significantly influencing postural control were Angle Class (p < .001), crowding (p = .006), midline deviation (p < .001), crossbite (p < .001), anterior open bite (p = .05), and overjet (p = .01). It could be concluded that the sensory information linked to the dental occlusion for the balance control comes strongly into effect in unstable conditions.
D. Clark Dickin and Jacqueline E. Heath
Whole body vibration (WBV) has been shown to improve force and power output as well as flexibility and speed, with improvements suggested to result from reduced electromechanical delays, improved rate of force development, and sensitivity of muscle spindles. Fixed frequency studies on postural control have been somewhat equivocal; however, individualized frequency protocols have shown promising results in other motor tasks. To assess this, 18 healthy young adults experienced three 4-minute WBV sessions with postural control assessed before vibration, after multiple exposures, and during recovery, with altered levels of sensory information available to the participants. Sway velocity, sway path length, and sway area were assessed in each environment. Study findings revealed that stability was impacted following WBV, with more challenging environments eliciting improvements persisting for 20 minutes. When the environment was less challenging, postural stability was impaired; however, the effects dissipated quickly (10-20 min). It was determined that exposure to individualized frequency WBV served to impair postural control when the challenge was low, but resulted in heightened stability when the overall challenge was high and vestibular information was needed for stability.
Most studies investigating movement preparation report substantial longer reaction times than studies probing response times to adjust an ongoing movement. However, both behaviors constitute control processes that transform sensory information about the environment into motor commands. Smeets, Oostwoud Wijdenes, and Brenner (2016) base their review on the hypothesis of a qualitative difference between the two sensorimotor control processes. By ruling out that the three latter movement stages proposed by Donders (1969)—identification, selection, and execution—are responsible for the difference, they argue for a specific role of the detection stage. Specifically, they reason that the detection in (target) change is only necessary for movement initiation and thus constitutes the qualitative difference between the two behaviors. In contrast to this view, I will advocate that change detection is not a qualitatively discriminating feature between the two processes. Instead, the difference in response time might rather stem from different decision criteria (Wolpert & Landy, 2012) set on the detection threshold. This threshold is rather conservative for movement initiation and more relaxed for online adjustments. However, both are states on the same continuum. Thus, movement initiation and online adjustments might even not be qualitatively different at all.