A dynamical systems analysis of spontaneous movements in newborn infants
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Published on: June 1, 2015
Shohei Ohgi1, Satoru Morita, Kek Khee Loo
1Department of Rehabilitation Science, Seirei Christopher University, Hamamatsu, Shizuoka, Japan. shohei-o@seirei.ac.jp
Insights
Newborn infants
Area of Science:
- Neuroscience
- Developmental Biology
- Biophysics
Background:
- Infants' spontaneous movements are crucial for motor development.
- Understanding the underlying dynamics of these movements can provide insights into early motor control.
Purpose of the Study:
- To analyze the dynamical characteristics of spontaneous movements in healthy newborn infants.
- To investigate whether these movements exhibit nonlinear chaotic dynamics.
Main Methods:
- Utilized dynamical systems analysis on limb acceleration data from 6 healthy 1-month-old infants.
- Employed triaxial accelerometers to record 3D limb acceleration signals.
- Applied both linear and nonlinear time series analysis techniques.
Main Results:
- Nonlinear time series analysis indicated that infants' spontaneous movements are characterized by nonlinear chaotic dynamics.
- The analysis suggested an embedding dimension of 5 or 6 for these movements.
- These findings imply that chaotic dynamic systems are involved in the production of infant movements.
Conclusions:
- Infants' spontaneous movements exhibit complex, nonlinear dynamics.
- Chaotic dynamic systems play a role in generating voluntary skill movements in newborns.
- This research offers a novel perspective on the biomechanics and neural control of early infant motor behavior.
Abstract:
The authors evaluated the characteristics of infants' spontaneous movements by using dynamical systems analysis. Participants were 6 healthy 1-month-old full-term newborn infants (3 males, 3 females). They used a triaxial accelerometer to measure limb acceleration in 3-dimensional space. Acceleration signals were recorded during 200 s from the right wrist when the infant was in an active alert state and lying supine (sampling rate 200 Hz). and was stored in the system's memory. Digitized data were transferred to a PC for subsequent processing with analysis software. The acceleration time series data were analyzed linearly and nonlinearly. Nonlinear time series analysis suggested that the infants' spontaneous movements are characterized by a nonlinear chaotic dynamics with 5 or 6 embedding dimensions. The production of infants'spontaneous movements involves chaotic dynamic systems that are capable of generating voluntary skill movements.
