scholarly journals Specificity of Muscle Fatigue in Hemiplegia and Normal Subjects with E.M.G. Power Spectral Analysis.

1996 ◽  
Vol 11 (4) ◽  
pp. 173-177
Author(s):  
TOSIYUKI FUKUDA ◽  
KAZUFUMI ARAYA
Keyword(s):  
Spectral Analysis ◽  
Muscle Fatigue ◽  
Power Spectral Analysis ◽  
Normal Subjects ◽  
Power Spectral

Usefulness of Power Spectral Analysis for Measurement of Local Muscle Fatigue during Keyboard Task

1999 ◽  
Vol 11 (4) ◽  
pp. 449
Author(s):  
Soon Young Kwon ◽  
Chung Yill Park ◽  
Jung Wan Koo ◽  
Hyeon Woo Yim ◽  
Kang Sook Lee
Keyword(s):  
Spectral Analysis ◽  
Muscle Fatigue ◽  
Power Spectral Analysis ◽  
Power Spectral ◽  
Local Muscle Fatigue

Schizophrenia and Spectral Analysis of the Visual Evoked Potential

1984 ◽  
Vol 145 (5) ◽  
pp. 496-501 ◽  
Author(s):  
J. W. Jutai ◽  
J. H. Gruzelier ◽  
J. F. Connolly ◽  
R. Manchanda ◽  
S. R. Hirsch
Keyword(s):  
Spectral Analysis ◽  
Visual Information ◽  
Right Hemisphere ◽  
Power Spectral Analysis ◽  
Normal Subjects ◽  
Group Differences ◽  
Power Spectral ◽  
Intensity Changes ◽  
The Right ◽  
Visual Evoked

SummaryPower spectral analysis was performed on the visual evoked potentials (VEPs) recorded in response to flashes of different intensity in both unmedicated schizophrenic and normal subjects. At occipital locations (01, 02), schizophrenics showed less power than normals in the 10–14 Hz frequency range. In the 18–22 Hz range, schizophrenics showed under-activation in the left hemisphere and over-activation in the right. At temporal locations (T3, T4), schizophrenics showed abnormal (left greater than right) hemisphere patterns of activation in 10–14 Hz and 18–22 Hz ranges. There were no group differences in relationships between power and intensity changes at vertex (Cz). The results suggest abnormal cortical-subcortical interactions during analysis of visual information in schizophrenia.

Impact of Changes in Respiratory Frequency and Posture on Power Spectral Analysis of Heart Rate and Systolic Blood Pressure Variability in Normal Subjects and Patients with Heart Failure

1996 ◽  
Vol 91 (1) ◽  
pp. 35-43 ◽  
Author(s):  
John E. Sanderson ◽  
Leata Y. C. Yeung ◽  
Dickens T. K. Yeung ◽  
Richard L. C. Kay ◽  
Brian Tomlinson ◽  
...  
Keyword(s):  
Heart Failure ◽  
Blood Pressure ◽  
Heart Rate ◽  
Spectral Analysis ◽  
High Frequency ◽  
Low Frequency ◽  
Power Spectral Analysis ◽  
Normal Subjects ◽  
Power Spectral ◽  
Patients With Heart Failure

1. Autonomic dysfunction is a major feature of congestive cardiac failure and may have an important role in determining progression and prognosis. The low-frequency/high-frequency ratio derived from power spectral analysis of heart rate variability has been proposed as a non-invasive method to assess sympatho-vagal balance. However, the effects of different respiratory rates or posture are rarely accounted for, but may be relevant in patients with heart failure in whom clinical improvement is accompanied by a fall in respiratory rate and an increased proportion of the day in the upright position. 2. We have assessed the effect of controlled respiration at different rates (10, 15, 20 breaths/min or 0.17, 0.25 and 0.33 Hz), while supine and standing, on power spectral analysis of heart rate and blood pressure variability in 11 patients with heart failure and 10 normal subjects. 3. Heart rate variance and low-frequency power (normalized units) were reduced in patients with heart failure (absent in six). During controlled breathing while supine, the power of the high-frequency component was significantly greater at 10 breaths/min than at 20 breaths/min in patients with heart failure, whether expressed in absolute units (P = 0.005) or percentage of total power (P = 0.03). 4. On standing, controlled breathing in patients with heart failure produced less change in high-frequency power (P = 0.054), but the low-frequency/high-frequency ratio at lower respiratory rates was reduced (P = 0.05). In normal subjects, as expected, respiratory rate had a highly significant effect on high-frequency power. Also, in normal subjects there was the expected increase in heart rate low-frequency power (P = 0.04) moving from supine to standing with an increase in the low-frequency/high-frequency ratio (P = 0.003), while in the patients with heart failure this was absent, reflecting blunted cardiovascular reflexes. 5. Systolic blood pressure low- and high-frequency components and their ratio were significantly affected by respiration (P > 0.03) and change in posture (P > 0.03) in both patients with heart failure and normal subjects, with a significant increase in the low-frequency/high-frequency ratio (P = 0.03) on standing in patients with heart failure, indicating that autonomic modulation of blood pressure is still operating in heart failure. 6. Thus, respiratory rate and changes in posture have a significant effect on measurements derived from spectral analysis of heart rate and blood pressure variability. Studies that use power spectral analysis as a measure of sympatho-vagal balance should control for these variables.

20 Influence of postural change on the sympathovagal balance, estimated by power spectral analysis of heart rate nervous variability in normal subjects

1993 ◽  
Vol 11 (5) ◽  
pp. S404
Author(s):  
L. Bieniaszewski ◽  
Andrzej Rynkiewicz ◽  
Jaroslaw Furmanski ◽  
Krzysztof Narkiewicz ◽  
Barbara Krupa-Wojciechowska
Keyword(s):  
Heart Rate ◽  
Spectral Analysis ◽  
Power Spectral Analysis ◽  
Normal Subjects ◽  
Sympathovagal Balance ◽  
Postural Change ◽  
Power Spectral

Needle EMG of the human diaphragm: Power spectral analysis in normal subjects

1996 ◽  
Vol 19 (3) ◽  
pp. 324-330 ◽  
Author(s):  
Robert Chen ◽  
Stephen J. Collins ◽  
Hussein Remtulla ◽  
Anthony Parkes ◽  
Charles F. Bolton
Keyword(s):  
Spectral Analysis ◽  
Power Spectral Analysis ◽  
Normal Subjects ◽  
Power Spectral
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