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1.
2.
In patients suffering from Parkinson's disease (PD), we analyzed correlations between the parameters of contingent negative
variation (CNV) and data of variational pulsometry (according to the measurements of R-R ECG intervals). Studies were carried
out on 35 patients (group PD), 49 to 74 years old, with the stage of disease of 1.5 to 3.0 according to the Hoehn-Yahr international
classification. In the course of CNV recording (i.e., in the state of a certain functional loading), we observed significant
negative correlations between the integral magnitude (area) of this potential and indices of variational pulsometry (RMSSD,
SDNN, C. var, and HF) that characterize the intensity of parasympathetic (respiratory) influences on the cardiovascular system.
In the control group, such correlations were absent. We found significant correlations between the autonomic balance, CNV
magnitude, and stage of PD reflecting the level of generalization of the pathological process. In the subgroup of patients
with the PD stage 1.5 to 2.0, significant changes in the mean values of indices of parasympathetic influences during recording
of the CNV were not observed, while in another subgroup (the PD stage 2.5 to 3.0), these values increased significantly (P < 0.05 and P < 0.01). If the estimates of the PD stage were low, the CNV area demonstrated greater values (P < 0.01). The disturbance of coordination of muscle-to-muscle interactions in the PD group is, probably, an important factor
responsible for parasympathetic dysregulation and suppression of the CNV generation. We found positive correlation between
the intensity of parasympathetic influences in the course of CNV recording and the level of postural disorders (r = 0.37, P < 0.05). On the contrary, the CNV magnitude demonstrated a negative correlation with the intensity of these disorders (r = −0.36, P < 0.05), as well as with the level of postural instability (r = −0.55, P < 0.001). We hypothesize that alterations of the autonomic balance and the activity of those cerebral structures, which are
responsible for the motor readiness, result, to a significant extent, from weakening of the activity of the noradrenergic
system due to degenerative processes developing in cells of the locus coeruleus. The impairment of the latter structure, together with degeneration of neurons of the substantia nigra and a decrease in the level of nigro-striatal dopamine, underlies the pathomorphological pattern of PD.
Neirofiziologiya/Neurophysiology, Vol. 40, No. 3, pp. 242–253, May–June, 2008. 相似文献
3.
J. Peter Rosenfeld Antoinette M. Reinhart Sanjay Srivastava 《Applied psychophysiology and biofeedback》1997,22(1):3-20
Two different groups of normal college students were formed: One (the alpha group) received 10-Hz audiovisual (AV) stimulation for 8 minutes, and the other (beta) group received 22-Hz AV stimulation for 8 minutes. EEG power in the alpha (8-13 Hz) and beta (13-30 Hz) bands was FFT-extracted before, during, and for 24 minutes after stimulation. It was found that baseline (prestimulation) alpha and beta power predict the effects of stimulation, leading to individual differences in responsivity. High-baseline alpha participants showed either no entrainment or relatively prolonged entrainment with alpha stimulation. Low-baseline participants showed transient entrainment. Baseline alpha also predicted the direction of change in alpha with beta stimulation. Baseline beta and alpha predicted beta band response to beta stimulation, which was transient enhancement in some participants, inhibition in others. Some participants showed relatively prolonged beta enhancement with beta stimulation. 相似文献
4.
《Current biology : CB》2022,32(1):190-199.e3
5.
《Current biology : CB》2021,31(24):5512-5521.e5
Download : Download video (29MB) 相似文献
6.
苏林娜刘向强吕丽芬聂勇战时永全 《现代生物医学进展》2014,14(10):1875-1878
目的:研究FXR在胃炎,胃粘膜肠化生及胃癌组织中的表达,分析其在胃癌发生中的意义。方法:采用免疫组化方法检测FXR在55例胃炎组织,61例胃黏膜肠化生组织及61例胃癌组织中的表达,利用统计学方法 SPSS17.0软件分析其在三种组织中的表达变化,结合文献回顾,分析FXR在胃癌发生中的意义。结果:FXR在胃黏膜肠化生中的表达明显高于胃炎组织(P0.05),而在胃癌组织中,FXR的表达显著低于胃粘膜肠化生组织(P0.05)。结论:FXR是一个潜在的胃癌发生生物标记物,其具体机制有待于进一步探索。 相似文献
7.
8.
I. N. Konareva 《Neurophysiology》2006,38(3):201-208
Modifications of different EEG rhythms induced by a single neurofeedback session (by the EEG characteristics) directed toward
an increase in the ratio of the spectral powers (SPs) of the α vs θ oscillations were compared with the psychological characteristics of the tested subjects (the group included 30 persons).
A generally accepted neurofeedback technique was used; the intensity of acoustic white noise served as the feedback signal.
EEG potentials were recorded from the C3 and C4 leads. Psychological testing was carried out using Eysenck’s (EPQ), Rusalov’s
(OST), and (16 PF) questionnaires. The directions of changes in the SPs of EEG frequency components were found to significantly
correlate with some individuality-related peculiarities of the tested subjects. The SP of the δ rhythm correlated with the
EPQ scale “neuroticism,” OST scale “social plasticity,” and 16 PF factors H (“parmia”), I (“premsia”), and Q3 (“self-control of behavior”). The SP of the θ component demonstrated correlations with the OST scales “ergisity,” “plasticity,”
and “social temp” and with 16 PF factors M (“autia”), Q4 (“frustration”), and Q1 (“exvia”). The SP of the α rhythm correlated with 16 PF factors Q3 (“self-control of behavior”), G (“strength of superEgo”), O (“hypothymia”), L (“protension”), and N (“shrewdness”). The SP
of the β rhythm correlated with the OST scale “emotionality,” while that of the γ rhythm showed correlations with the 16 PF
indices L (“protension”) and M (“autia”). Changes in the ratio of the α vs θ SPs correlated with the EPQ scale “neuroticism.” Thus, our data confirm the statement that a high individual variability
of the results of a single (first in the series) neurofeedback session is to a great extent related to peculiarities of the
individual psychological pattern of the subject.
Neirofiziologiya/Neurophysiology, Vol. 38, No. 3, pp. 239–247, May–June, 2006. 相似文献
9.
The contingency of variations in amplitude—frequency parameters of the main modes of extremely-low-frequency resonances of an ionospheric waveguide (Schumann resonances) and changes in human encephalograms in the frequency range of 6–16 Hz has been studied. The results obtained with the use of synchronized monitoring suggest that such contingency, expressed as indices of cross-correlation function, is statistically significant, varying from 0.12 to 0.65 at α = 0.95. It has been established that contingency is largely determined by the current level of solar and geomagnetic activity. 相似文献
10.
E. P. Man’kovskaya 《Neurophysiology》2006,38(3):197-200
We compared changes in the EEG indices in healthy dextral volunteers performing static force grasps by the arm. Three test
modes were used: (i) performance of two successive grasps by the dominant (right) arm (test A), (ii) performance of two successive
grasps by the subdominant (left) arm (test B), and (iii) performance of the grasps first by the right arm and then by the
left arm (test C). Fourteen, six, and nine persons took part in tests A–C, respectively. In the course of grasps performed
by the right and left arms, bilateral increases in synchronization within the alpha 1 and alpha 2 ranges were frequently observed
in occipital regions in both the first and repeated grasps (P < 0.05). Consecutive grasps by the right arm were accompanied by clear desynchronization in a few anterior and central leads.
Alpha 2 desynchronization was observed in both realizations of the left-arm grasps (test B) performed by some subjects, but
intragroup modifications were not significant in this case. The coherence coefficients of the alpha 2 rhythm in most cases
increased for symmetric leads from the right and left hemispheres in the course of grasps by both the right and left hands.
The effect of intensification of interhemisphere links was manifested in the anterior and central cortical regions; this fact
showed that interhemisphere interaction increases in the course of the static effort. Changes in the coherence coefficients
for the alpha 2 range in the performance of the grasp efforts by the right arm and the left arm were most clear in the posterotemporal
(P = 0.02), parietal (P = 0.05), and anterofrontal (P = 0.06) lead pairs. Thus, we demonstrated the dependence between the side of performance of the muscle effort in the mode
close to isometric and lateralization of the EEG modifications.
Neirofiziologiya/Neurophysiology, Vol. 38, No. 3, pp. 235–238, May–June, 2006. 相似文献