1996 Fiscal Year Final Research Report Summary
Portable bioelectrical measurement system for longitudinal developmental study of nervous system functions in infants.
| Project/Area Number |
06558006
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 試験 |
|---|
| Research Field |
体育学
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
MIYASHITA Mitsumasa The University of Tokyo, Graduate school of education, Professor, 大学院・教育学研究科, 教授 (80023571)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KOICHI Masaharu Business office of Hongo, Nihon Kohden Tokyo, Corporation.Chief, 本郷第二営業所, 所長
YAMAMOTO Yoshiharu The University of Tokyo, Graduate school of education, Professor, 大学院・教育学研究科, 助教授 (60251427)
|
|---|
| Project Period (FY) |
1994 – 1996
|
| Keywords | Digital Audio Tape / portable bioelectrical measurement system / infants / reciprocal excitation / heart rate variability |
|---|
| Research Abstract |
We developed a portable bioelectrical measurement system which consists of a DAT (Digital Audio Tape) recorder and a small bio-amplifier to study the development of nervous system functions in infants.
We first investigated the longitudinal development of reciprocal innervation to examine developmental changes in human motor nervous system. The "radiated" stretch reflex to antagonist muscle in infants and adults, termed "reciprocal excitation", was evaluated. The phasic stretch reflex and the reciprocal excitation were evoked by the Achilles tendon tapping. The surface electromyogram was recorded in the soleus and the tibialis anterior. The reciprocal excitation increased at around the developmental stage of acquisition of standing, and decreased after the acquisition of walking. It was suggested that the spinal neural pathway of reciprocal innervation changed dramatically at these stages of motor development and these changes were related to the acquisition of movements.
We next investi
… More
gated longitudinal changes in the autonomic nervous system activities during the first year of life. Beat-to-beat heart rate variability (HRV ; 600 beats) was recorded from 6 healthy infants (5 males, 1female). HRV data were analyzed by coarse graining spectral analysis to break down their total power (TOT) into harmonic and nonharmonic (fractal) components. The harmonic component was further divided into low (0.0-0.15Hz ; LF)and high (>0.15Hz ; HF)frequency components. The sympathetic (SNS) and parasympathetic (PNS) nervous system activities were evaluated from log (LF/HF) and log (HF/TOT), respectively. The fractal component has the spectrum of 1/f^<beta> and the spectral exponent beta was calculated. There was no consistent pattern of development for SNS and PNS activity indicators among individuals. Spectral exponent beta was, however, negatively correlated (P<0.05)with postnatal age for 4 infants and it tended to decrease rapidly after about 240th day of life. These results indicated that the complexity of HRV increased during postnatal life. Less
|
