Development of human locomotion

Lacquaniti, Francesco; Ivanenko, Yuri P.; Zago, Myrka

doi:10.1016/j.conb.2012.03.012

Cited by 90 publications

(57 citation statements)

References 69 publications

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“…More gradual development in walking occurs until 8 -10 yr of age (Lacquaniti et al 2012). In general, the walking pattern of children shows greater variability compared with that of adults (Dominici et al 2010;Petersen et al 2010).…”

Section: Discussionmentioning

confidence: 97%

Locomotor sequence learning in visually guided walking

Choi

Jensen

Nielsen

2016

Journal of Neurophysiology

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Choi JT, Jensen P, Nielsen JB. Locomotor sequence learning in visually guided walking. J Neurophysiol 115: 2014 -2020, 2016. First published February 10, 2016 doi:10.1152/jn.00938.2015.-Voluntary limb modifications must be integrated with basic walking patterns during visually guided walking. In this study we tested whether voluntary gait modifications can become more automatic with practice. We challenged walking control by presenting visual stepping targets that instructed subjects to modify step length from one trial to the next. Our sequence learning paradigm is derived from the serial reaction-time (SRT) task that has been used in upper limb studies. Both random and ordered sequences of step lengths were used to measure sequence-specific and sequence-nonspecific learning during walking. In addition, we determined how age (i.e., healthy young adults vs. children) and biomechanical factors (i.e., walking speed) affected the rate and magnitude of locomotor sequence learning. The results showed that healthy young adults (age 24 Ϯ 5 yr, n ϭ 20) could learn a specific sequence of step lengths over 300 training steps. Younger children (age 6 -10 yr, n ϭ 8) had lower baseline performance, but their magnitude and rate of sequence learning were the same compared with those of older children (11-16 yr, n ϭ 10) and healthy adults. In addition, learning capacity may be more limited at faster walking speeds. To our knowledge, this is the first study to demonstrate that spatial sequence learning can be integrated with a highly automatic task such as walking. These findings suggest that adults and children use implicit knowledge about the sequence to plan and execute leg movement during visually guided walking.human; learning; locomotion; vision; walking THE AUTOMATIC CONTROL OF WALKING is critical to our daily activities. We normally do not consciously think about walking unless we encounter novel situations where we have to make voluntary gait modifications (e.g., hiking across stepping stones). On the other hand, voluntary control of stepping patterns can become more automatic with practice (e.g., line dancing). Locomotor skills can be learned via visual cues from the environment or proprioceptive cues from the limbs during obstacle avoidance tasks (Erni and Dietz 2001;Lajoie et al. 2012). Moreover, there is some evidence that visual cue training could improve gait patterns that transfer to walking without cues in people with Parkinson's disease (Spaulding et al. 2013).The classic serial reaction-time (SRT) task, first introduced by Nissen and Bullemer (1987), may be used to assess to what an extent a motor task has become automatic. The SRT task requires subjects to rapidly respond to different spatial cues by pressing corresponding buttons as fast and accurately as possible. With practice, subjects demonstrate learning by performing faster on the repeating sequence than on random sequences. This difference can only be accounted for by sequence-specific learning, which can occur with or without explicit knowledge (Coh...

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Section: Discussionmentioning

confidence: 97%

Locomotor sequence learning in visually guided walking

Choi

Jensen

Nielsen

2016

Journal of Neurophysiology

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“…The optimization of timing and amplitude of muscle activity represents an important feature of motor patterns development (Forssberg, 1985; Hadders-Algra et al, 1992; Lacquaniti et al, 2012a). The functional reorganization of the spinal motor output during early development consists in a gradual shift of the timing of stance related muscle activity and corresponding activity of the sacral segments of the spinal cord (Ivanenko et al, 2013a; Figure 7), and a gradual decrease of the EMG burst duration with age (Figures 4, 5B,C): the older the child, the closer the waveform to the adult.…”

Section: Discussionmentioning

confidence: 99%

“…Using these approaches, it has been shown that the development of locomotion in typically developing (TD) children involves a functional reorganization of the spinal locomotor output. In particular, the number of basic muscle activation patterns increases from the neonate to the toddler (Dominici et al, 2011; Lacquaniti et al, 2012a), and the temporal dynamics of MN activation in lumbar and sacral spinal segments undergoes structured functional changes during early locomotor development (Ivanenko et al, 2013a). How these developmental processes are altered in children with CP remains largely unknown.…”

Section: Introductionmentioning

confidence: 99%

Immature Spinal Locomotor Output in Children with Cerebral Palsy

et al. 2016

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Detailed descriptions of gait impairments have been reported in cerebral palsy (CP), but it is still unclear how maturation of the spinal motoneuron output is affected. Spatiotemporal alpha-motoneuron activation during walking can be assessed by mapping the electromyographic activity profiles from several, simultaneously recorded muscles onto the anatomical rostrocaudal location of the motoneuron pools in the spinal cord, and by means of factor analysis of the muscle activity profiles. Here, we analyzed gait kinematics and EMG activity of 11 pairs of bilateral muscles with lumbosacral innervation in 35 children with CP (19 diplegic, 16 hemiplegic, 2–12 years) and 33 typically developing (TD) children (1–12 years). TD children showed a progressive reduction of EMG burst durations and a gradual reorganization of the spatiotemporal motoneuron output with increasing age. By contrast, children with CP showed very limited age-related changes of EMG durations and motoneuron output, as well as of limb intersegmental coordination and foot trajectory control (on both sides for diplegic children and the affected side for hemiplegic children). Factorization of the EMG signals revealed a comparable structure of the motor output in children with CP and TD children, but significantly wider temporal activation patterns in children with CP, resembling the patterns of much younger TD infants. A similar picture emerged when considering the spatiotemporal maps of alpha-motoneuron activation. Overall, the results are consistent with the idea that early injuries to developing motor regions of the brain substantially affect the maturation of the spinal locomotor output and consequently the future locomotor behavior.

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“…For example, walking and running show similarly patterned control of neural commands (Cappellini et al, 2006;Lacquaniti et al, 2012b) and become automatized motor gestures by experience, with primitive basic motor patterns which are innate (Lacquaniti et al, 2012a). When other tasks are added to a locomotion motor pattern, such as kicking during walking, additional modules and timing activation signals are added in a linear manner maintaining the basic structure of impulsive control (Ivanenko et al, 2005).…”

Section: Introductionmentioning

confidence: 99%

Fast changes in direction during human locomotion are executed by impulsive activation of motor modules

et al. 2013

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This study investigated the modular control of complex locomotor tasks that require fast changes in direction, i.e., cutting manoeuvres. It was hypothesized that such tasks are accomplished by an impulsive (burst-like) activation of a few motor modules, as observed during walking and running. It was further hypothesized that the performance in cutting manoeuvres would be associated to the relative timing of the activation impulses. Twenty-two healthy men performed 90° side-step cutting manoeuvres while electromyography (EMG) activity from 16 muscles of the supporting limb and trunk, kinematics, and ground reaction forces were recorded. Motor modules and their respective temporal activations were extracted from the EMG signals by non-negative matrix factorization. The kinematic analysis provided the velocity of the centre of mass and the external work absorbed during the load acceptance (negative work, external work during absorption (W-Abs)) and propulsion phases (positive work, external work during propulsion (W-Prp)) of the cutting manoeuvres. Five motor modules explained the EMG activity of all muscles and were driven in an impulsive way, with timing related to the initial contact (M2), load acceptance (M3), and propulsion (M4). The variability in timing between impulses across subjects was greater for cutting manoeuvres than for running. The timing difference between M2 and M3 in the cutting manoeuvres was significantly associated to W-Abs (r(2)=0.45) whereas the timing between M3 and M4 was associated to W-Prp (r(2)=0.43). These results suggest that complex locomotor tasks can be achieved by impulsive activation of muscle groups, and that performance is associated to the specific timing of the activation impulses.

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Development of human locomotion

Cited by 90 publications

References 69 publications

Locomotor sequence learning in visually guided walking

Locomotor sequence learning in visually guided walking

Immature Spinal Locomotor Output in Children with Cerebral Palsy

Fast changes in direction during human locomotion are executed by impulsive activation of motor modules

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