29th International Congress of Clinical Neurophysiology
S113
intervals of heart rate and brain waves were analyzed for the evaluation of ANS and CNS function, respectively. This study was approved by the Ethics Committee of Shizuoka University. Results: Inhalation of the odor from YBGE in most subjects, but not all, tended to produce an increase in both parasympathetic nervous activity and in brain wave alpha/beta ratio. Conclusions: The odor of YBGE tended to stimulate ANS and CNS activity in within human subjects, but the extent of these changes varied individually, suggesting that an association between ANS and CNS is involved in odor-induced anti-stress in nervous system function. Further studies are required to further elucidate the effects of odor of green plants on the nervous system.
during standing (Pearson r = 0.3176, p = 0.007) but not with R-R variation during deep breathing or Valsalva maneuver. No correlation was found between SSRPA or SSRNA with R-R interval based tests or with bloodpressure response to standing. Fifty-four subjects were able to complete the test of blood-pressure response to sustained handgrip and results were within normal. Conclusion: SSR is a convenient tool in evaluating patients with autonomic dysfunction. It correlates with a parasympathetic component of the autonomic function tests.
P2-23 Time relationship between motor and sympathetic activation in a voluntary handgrip
C.-H. Lu1 , L.-H. Lee1 , C.-C. Huang1 Department of Neurology, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan
R. Tsukahara1 , Y. Kuwahara2 , S. Iwase2 , N. Nishimura2 , Y. Shimizu2 , J. Sugenoya2 1 Institute for Developmental Research, Aichi Human Service Center, Aichi, Japan, 2 Department of Physiology, Aichi Medical University, Nagakute, Japan Objective: We examined the time relationship between voluntary muscle contraction and sympathetic outflow directed to glabrous skin areas to address the possible contribution of central motor commands to sympathetic activation. Methods: Twelve healthy subjects performed a brief handgrip (HG) in response to an imperative visual cue. Electromyographic (EMG) signals were recorded from the forearm muscles. Skin sympathetic nerve activity (SSNA) was recorded microneurographically from the tibial nerve at the popliteal fossa. The onset latency of SSNA burst and the EMG reaction time from the visual cue were analyzed for each subject. Time measurements of SSNA burst in the HG task were compared with the reflex latency of SSNA burst evoked by an electrical stimulus. Results: The intraindividual mean of the onset latency of SSNA burst from the visual cue ranged from 724 ms to 1344 ms in the HG task, which was significantly longer than the reflex latency of SSNA burst (650 911 ms) to an electrical stimulation. The onset latency of SSNA burst in the HG task was correlated with EMG reaction time for each subject (correlation coefficient = 0.5 0.77). The time interval from EMG burst to SSNA burst was 483 789 ms, which was significantly shorter than the reflex latency of SSNA burst. These results showed that the SSNA burst temporally associated with the voluntary execution of HG rather than the perception of the visual cue or afferent feedback from contracting muscles. Conclusion: A central motor process may play an important role in SSNA burst accompanying a brisk voluntary movement. P2-24 Normative values of sympathetic skin response (SSR) and correlation of SSR with R-R interval based autonomic function tests S.S. Jayasinghe1 , K.D. Pathirana2 Department of Pharmacology, Faculty of Medicine, University of Ruhuna, Sri Lanka, 2 Clinical Neuroscience Center, Department of Medicine, Faculty of Medicine, University of Ruhuna, Sri Lanka
P2-25 Long-term effects of baroreflex function in patients who had carotid stenosis underwent carotid stenting 1
Background: Baroreflex sensitivity has been recognized as having prognostic relevance for cardiovascular and cerebrovascular risks. However, little is known about the long-term outcome of baroreflex function in patients who had carotid stenosis undergoing carotid stenting. Methods: We examined heart rate variability and cardiovascular autonomic function including baroreflex sensitivity by using non-invasive methods in 22 adult patients (73.8±8.3) that underwent carotid stenting. These patients were compared with two control groups, the one with 22 sex and age-matched normal volunteer subjects (70.9±7.3), and the other with 10 adult patients (71.1±9.0) that had severe stenosis or even total occlusion of carotid artery without stenting. Results: The two patient groups have significantly reduced valsalva ratio, baroreflex sensitivity measured by valsalva method, and heart rate response during head-up tilt test compared to normal controls, but there is no significant difference between two patient groups. There is significant decrement of heart rate response to deep breathing in patients with carotid stenting compared to normal controls. Other parameters of cardiovascular autonomic function show no difference among three groups. Conclusions: The reduced baroreceptor function in patients with carotid stenting is likely due to underlying diseases rather than the procedure of stenting. Parasympathetic hyperactivity short-term after stenting does not show in our results, suggesting that the effect is transient rather than permanent. P2-26 A novel index of sympathovagal balance from independent component analysis of heart rate and blood pressure variability L.-H. Lee1 , C.-C. Huang1 , C.-H. Lu1 1 Department of Neurology, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan
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Introduction: R-R interval based autonomic function tests are used for the diagnosis of autonomic dysfunction, which are time consuming and depend on patients effort. SSR can be used to assess sympathetic sudomotor system but the normative values are lacking. Our aim was to find out normative values of SSR and correlation of SSR with R-R based autonomic function tests. Methods: SSR latency (SSRL) and amplitude of positive (SSRPA) and negative (SSRNA) components of the dominant hand, R-R interval variation during standing, deep breathing and Valsalva maneuver, bloodpressure response to standing and sustained handgrip were measured in 70 (50 males) healthy subjects. The mean (SD) were calculated for each parameter and the correlation of the SSRL, SSRPA and SSRNA with the R-R interval based autonomic function tests were done using Pearson correlation coefficient. Results: The mean age was 33±12 years. The mean SSRL was 1544.0±152.3 ms. The mean SSRPA and SSRNA were 1.19 mV (inter quartile range 0.41 1.74) and 0.69 mV (inter quartile range 0.39 0.94) respectively. The mean R-R interval variation during standing, deep breathing and Valsalva maneuver were 1.343±0.277, 27±10 beats and 1.694±0.317 respectively. SSRL had positive correlation with R-R variation
We applied independent component analysis (ICA) to oscillations of HR and blood pressure (BP) in order to obtain an index of sympathovagal balance. We tested the performance of this index in patients with carotid stenting (CAS) according the following criteria: (1) the index should vary similarly among subjects in response to different autonomic conditions; (2) the variability in the index among subjects exposed to the same autonomic conditions should be small; and (3) the response of the index to various autonomic conditions should reflect the underlying changes in the physiological state and have a meaningful interpretation. We performed ECG and BP measurements for 10 minutes of resting in the supine position followed by 5 minutes with head-up tilt to 70 degree in 20 patients who had undergone carotid artery stenting (CAS) and 20 sex- and age-matched normal volunteer subjects. HRV was analyzed using the spectral technique in order to calculate the power ratio between the low-frequency (LF) and high-frequency (HF) bands. ICA was applied to the oscillations of HR and systolic BP in order to obtain 2 independent components (ICs). The one with power spectrum predominantly in the LF band was denoted as IC1 while the other was IC2. Compared to the commonly used LF/HF ratio, the IC1/IC2 power ratio in the LF band (IC1_L/IC2_L) had a lower coefficient of variance and higher R2 value in a general linear model, suggesting that this parameter better fulfilled the first 2 criteria. Both IC1_L/IC2_L and LF/HF were significantly increased in the standing position compared with that in the supine position, suggesting that the last criterion was