ラット眼か下神経挫滅後の触覚性誘発電位の回復過程の研究

In this study, simple propositions and compound propositions are emphasized. Compound propositions, such as conjunction, disjunction, conditional, biconditional, incompatibility, joint denial and noninclusive disjunction are included. It examines which of these compound propositions can be directly reduced to their constituent simple propositions and which of them cannot be directly reduced to their constituent simple propositions. In this regard, the truth table method was used in the context of two-valued logic. With this method, simple propositions and compound propositions that are equivalent and not equivalent to each other are put forward, and it is tried to show which compound propositions can be reduced to their constituent simple propositions, and which compound propositions cannot be reduced to their constituent simple propositions. In this context, the following points are put forward: positive simple propositions can be reduced to the propositions of affirmed conjunctions with two positive components, the affirmed disjunctions with two positive components, the affirmed conditional with the negative leading component and positive posterior component, the affirmed incompatibility with both negative components, the affirmed joint denial with both negative components, the negated incompatibility with both positive components, the negated joint denial with both positive components, the negated conditional with the positive leading component and negative posterior component, the negated conjunction with both negative components, and the negated disjunction with both negative components. Negative simple propositions can be reduced to the propositions of the affirmed incompatibility with both positive components, the affirmed joint denial with both positive components, the affirmed conditional with positive leading component and negative posterior component, the affirmed conjunction with both negative components, the affirmed disjunction with both negative components, the negated conjunction with both positive components, the negated disjunction with both positive components, the negated conditional with negative leading component and positive posterior component, the negated incompatibility with both negative components, and the negated joint denial with both negative components.

Is the afferent pathway from the rectum impaired in children with chronic constipation and encopresis?

This paper presents a single-trial evoked potential (EP) estimation method based on an autoregressive model with exogenous input modeling and sparse coding. This method uses sparse coding instead of the autoregressive-moving-average model to model EPs, as the former is more flexible. The best matching atoms from the dictionary are used to represent the EP signal without needing to estimate the number of atoms beforehand. By transforming the electroencephalography signal into white noise, the single-trial EP estimation is transformed into a signal denoising problem for white noise. With the dictionary constructed specially for EPs, the EP signal can be extracted easily with sparse coding. Moreover, since the location of the atom in the dictionary has no influence on the effectiveness of sparse decomposition, variations of the amplitude and latency of EPs have only a minor impact on the performance of the proposed method. The proposed method can thus track EP signal variations. Experimental results also demonstrate that this method is effective.

Evoked potential correlates of intelligence: Some problems with Hendrickson's string measure of evoked potential complexity and error theory of intelligence

The second-order generalized integrator (SOGI) and cascade delayed signal cancellation (DSC) have been used respectively in the separation of positive and negative component. But they have their own disadvantages. In order to extract grid's positive and negative sequence fundamental component from unbalanced power system, the strategy of second-order generalized integrator eliminating higher harmonic and cascade delayed signal cancellation eliminating the specific frequency harmonic has been put forward in this article. It can quickly and accurately separate the positive and negative sequence fundamental component of the grid While grid voltage is distortion, symmetrical fault and asymmetric fault cases. Then, this new method is applied to unbalanced PWM rectifier.

Skin potential responses to tone, and tone plus light, were separated for analysis into positive and negative components. The positive component showed typical orienting response characteristics (in the Sokolov sense), whereas the negative seemed to reflect stimulus registration. Conditioning of the positive component did not occur.

Central Municipal Clinical Hospital No. 18, Kazan, Russia. Various mathematical methods (F-statistics, taxonomic algorithms, etc.) are routinely used for processing results of measurements of evoked potentials (EP) and other clinical electrophysiological data [5]. In addition, such relatively simple components of somatosensory EP (SSEP) as amplitude and latency should be monitored during medical treatment of patients. Because these parameters represent integrative activity of suprasegmentary brain structures, they are of substantial diagnostic value in various functional disorders [1, 3]. Comparative tables and histograms are usually compiled either based on numerical values of parameters of interest or on statistical difference from normal level. We suggest a new method of plotting histograms of combined changes of SSEP latency and amplitude components. According to this method, changes of SSEP latency and amplitude components are compared with normal and pathophysiologically substantiated parameters of the central nervous system (CNS) determined either clinically or experimentally. Statistical processing was based on the Student’s t-test for high (p 0.09) was considered as statistically insignificant. The effect of enhanced convulsion activity of the brain under conditions of chronic subthreshold excitation (kindling effect) was discovered by G. Goddard [7]. It was shown later by G. N. Kryzhanovsky [4, 8, 9] that these effects could be attributed to so-called generators of pathologically amplified excitation (GPAE). These generators are formed as a result of inhibition disorders in a pool of neurons generating an uncontrollable flux of pulses. The GPAE formation in the nociceptive sensitivity system gives rise to chronic pain syndrome. This is particularly pronounced in case of trifacial neuralgia. Both GPAE and other pathogenically significant brain states may cause a broad range of higher nervous activity dysfunctions. In terms of electrophysiological parameters, GPAE is charac-

Deep brain stimulation (DBS) of globus pallidus internus (GPi) has emerged as an effective treatment for primary generalized dystonia. However, the physiological mechanisms of improvement are not fully understood. Cortical activity in response to pallidal stimulation was recorded in 6 patients with primary generalized dystonia >6 months after bilateral GPi DBS. Scalp electroencephalogram was recorded using 60 surface electrodes during 10 Hz bipolar pallidal DBS at each electrode contact pair. Anatomical position of the electrode contacts in relation to the GPi, medial medullary lamina and globus pallidus externus (GPe) was determined from the postoperative stereotactic MRI. In all six patients an evoked potential (EP) was observed with average onset latency of 10.9 ms +/- 0.77, peak latency 26.6 ms +/- 1.6, distributed mainly over the ipsilateral hemisphere, maximal centrally. The mean amplitude of this potential was larger with stimulation in posteroventral GPi than in GPe (3.36 microV vs. 0.50 microV, P < 0.0001). The EP was absent in one patient-side, ipsilateral to a previous thalamotomy. Low frequency GPi stimulation produces an EP distributed centrally over the ipsilateral hemisphere. The latency and distribution of the EP are consistent with stimulation of pallidothalamic neurons projecting to the sensorimotor cortex. Because the EP is larger and more consistently present with stimulation of posteroventral GPi than GPe, it may provide a physiological tool to identify contacts within the optimal surgical target.

Background: Visceral hyperalgesia may play an important part in the pathophysiology of the irritable bowel syndrome (IBS). We investigated the neuronal afferent pathways in healthy volunteers and IBS patients by recording evoked potentials (EPs) elicited by electrical stimulation of the colon and abdominal skin inside and outside the referred pain area. Methods: Six healthy subjects and nine IBS patients met the inclusion criteria. Morphology and topography of EPs to painful electrical stimuli were estimated in the rectosigmoid junction and on the skin inside/outside the referred pain areas. Results: The EPs to painful stimuli of the gut showed a shorter latency and a smaller amplitude of the first positive peak (P1) in the IBS group. The controls had a mid-latency frontal positive component after 100 ms, whereas no reliable early activation was seen in the IBS patients. In controls, a single late (> 150 ms) positive component was seen, whereas the late component was biphasic in the IBS group. The EPs to painful stimuli of the two skin areas differed in IBS patients, but not in controls. Conclusion: Differences in the EPs to electrical painful stimulation of the sigmoid colon and skin inside/outside the experimentally evoked referred pain area were seen comparing healthy subjects and IBS patients. The results indicate altered central nervous system responses.

The effect of dichotic, monaural and diotic verbal stimuli on auditory evoked potentials

Evoked potentials of the lateral geniculate body were examined in cats during gaze holding and horizontal saccades elicited by a short flash against a homogeneous background. Statistical analysis showed that the positive component of evoked potentials recorded during gaze holding from the lateral geniculate body contralateral to the direction of the saccade did not differ from their positive component during saccades, but that the differences between the corresponding negative components were significant (p<0.01). Under the same conditions, both the positive and negative components of evoked potentials from the lateral geniculate body ipsilateral to the saccade's direction were found to be significantly suppressed during saccades but not during gaze holding.

The amplitude and temporal parameters of the N1 component of the auditory cognitive evoked potential (EP) were analyzed in ten people who participated in the elimination of the consequences of the Chernobyl accident (the liquidators) and ten healthy subjects aged 47 ± 6.0 and 50.5 ± 4.0 years, respectively. In the liquidators of the Chernobyl accident, the amplitudes of the N1 component of the auditory EP were decreased in all cortical areas. This decrease was the greatest in the central and frontal areas. The changes in response to stimuli of different significances in the liquidators were inverted as compared to the healthy subjects of the same age. The differences between the control group and the liquidators were the most pronounced in the temporal characteristics of the N1 component. The latent periods (LPs) for all stimuli presented under all experimental conditions were significantly shorter in the group of liquidators, and this effect was even stronger for the significant stimulus in the case of stimulus counting. In the liquidators, the maximum changes in the LPs of the N1 component were observed in the frontal area of the left hemisphere, and they were associated with an inversion of the LP asymmetry. Changes in this parameter were smaller in the central areas and were similar in the parietal areas in both groups studied. Changes in the amplitude and temporal characteristics of the N1 component of the auditory cognitive EP observed in the liquidators of the Chernobyl accident indicate the impairments of their involuntary attention and its capacity due to weakening of inhibition processes as compared to healthy subjects. This effect is similar to that found in elderly subjects. Our data support the hypothesis on the accelerated aging of the brain in the liquidators of the Chernobyl accident due to the effect of low doses of irradiation. The data also suggest that irradiation results in pathological aging.

P39-S Multimodal evoked potentials in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)

The P300 in pain evoked potentials

To achieve low cost and compactness, small dc capacitance in dc-link is preferred in the cascaded H-bridge (CHB) static synchronous compensator (STATCOM). However, small dc capacitance will definitely result in high dc-link ripples among three clusters, and thus cause severe third-order harmonic currents under the asymmetric grid. In this study, to mitigate the third-order harmonic currents, a selective component compensation approach for the CHB STATCOM is proposed. To study the effect of the dc-link ripples on the phase currents, sequence component decomposition is employed to derive the relationship between the dc-link ripples and the converter voltages. The relationship reveals that the converter voltages contain positive, negative, and zero sequence components in both fundamental and third-order under the asymmetric grid, while only the positive and negative sequence components in third-order converter voltages result in third-order harmonic currents due to the three-wire system. Therefore, the third-order harmonic currents suppression method is proposed by only compensating the positive and negative components in third-order converter voltages. A 380 V/15 kVA STATCOM prototype is built to verify the proposed control method.