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Purpose In between seizures, the brain of a patient with epilepsy will generate isolated, sporadic discharges (interictal epileptiform discharges [IEDs]). IED identification enables clinicians to diagnose epilepsy, and an understanding of IED waveforms may yield new insights into basic epilepsy mechanisms. I show that intracranial EEGs disclose a previously unreported negative polarity, low-voltage pre-potential at IED onset (i.e., a negative wave [n-wave]). I describe the features of n-waves and propose a plausible mechanism of their generation. Method In intracranial EEGs of the human neocortex, I assessed n-waves’ occurrence, anatomical location, amplitude, kinetics, and association with the subsequent positive pre-potential. I computed a model simulation of IED onset to identify plausible mechanisms behind n-wave generation. Results N-waves manifested in 40% of patients, in zones with and without seizures, and without a statistically significant prevalence in their anatomical location. These waveforms exhibited voltages of 140 + 42 μV and durations of 39.9 + 12.2 msec and were coupled with a positive pre-potential. In simulations of IED onset, n-waves can be generated by sequential recruitment of distinct microfoci over superficial cortical laminae. Conclusions N-waves represent an overlooked component of IED waveforms. They prolong the duration of IED onset and can facilitate synaptic hypersynchrony. They may also be associated with chronic epilepsy.

High-frequency electrical stimulation (HFS) of skin nociceptors triggers central sensitization (CS), manifested as increased pinprick sensitivity of the skin surrounding the site of HFS. Our aim was to assess the effect of CS on pinprick-evoked pupil dilation responses (PDRs) and pinprick-evoked brain potentials (PEPs). We hypothesized that the increase in the positive wave of PEPs following HFS would result from an enhanced pinprick-evoked phasic response of the locus coeruleus-noradrenergic system (LC-NS), indicated by enhanced PDRs. In 14 healthy volunteers, 64- and 96-mN pinprick stimuli were delivered to the left and right forearms, before and 20 minutes after HFS was applied to one of the two forearms. Both PEPs and pinprick-evoked PDRs were recorded. After HFS, pinprick stimuli were perceived as more intense at the HFS-treated arm compared with baseline and control site, and this increase was similar for both stimulation intensities. Importantly, the pinprick-evoked PDR was also increased, and the increase was stronger for 64- compared with 96-mN stimulation. This is in line with our previous results showing a stronger increase of the PEP positivity at 64 vs. 96-mN stimulation and suggests that the increase in PEP positivity observed in previous studies could relate, at least in part, to enhanced LC-NS activity. However, there was no increase of the PEP positivity in the present study, indicating that enhanced LC-NS activity is not the only determinant of the HFS-induced enhancement of PEPs. Altogether, our results indicate that PDRs are more sensitive for detecting CS than PEPs. NEW & NOTEWORTHY We provide the first demonstration in humans that activity-dependent central sensitization increases pinprick-evoked autonomic arousal measured by enhanced pupil dilation response.

Objective To investigate whether cool-evoked potentials (CEP) elicited by brisk innocuous cooling of the skin could serve as an alternative to laser-evoked potentials (LEP), currently considered as the best available neurophysiological tool to assess the spinothalamic tract and diagnose neuropathic pain. Methods A novel device made of micro-Peltier elements and able to cool the skin at −300 °C/s was used to record CEPs elicited by stimulation of the hand dorsum in 40 healthy individuals, characterize the elicited responses, and assess their signal-to-noise ratio. Various stimulation surfaces (40 mm2 and 120 mm2), cooling ramps (−200 °C/s and −133 °C/s) and temperature steps (20 °C, 15 °C, 10 °C, 5 °C) were tested to identify optimal stimulation conditions. Results CEPs were observed in all conditions and subjects, characterized by a biphasic negative-positive complex maximal at the vertex (Cz), peaking 190–400 ms after stimulus onset, preceded by a negative wave over central-parietal areas contralateral to the stimulated hand. Their magnitude was modulated by stimulation surface, cooling ramp and temperature step. Conclusion Rapid innocuous skin cooling elicits robust CEPs at latencies compatible with the conduction velocity of Aδ-fibers. Significance CEPs can be a complementary tool to the recording of LEPS for assessing the function of small-diameter Aδ-fibers and the spinothalamic tract.

The bounded traveling wave solutions of a generalized CamassaHolm-Novikov equation with p=2 and p=3 are derived via the dynamical system approach. The singular wave solutions including peakons and cuspons are obtained by the bifurcation analysis of the corresponding singular dynamical system and the orbits intersecting with or approaching the singular lines. The results show that the generalized Camassa-Holm-Novikov equation with p=2 and p=3 both admit smooth solitary wave, smooth periodic wave solutions, solitary peakons, periodic peakons, solitary cuspons and periodic cuspons as well. It is worth pointing out that the Novikov equation has no bounded traveling wave solutions with negative wave speed, but has a family of new periodic cuspons which are distinguished with the normal periodic cuspons for their discontinuous first-order derivatives at both maximum and minimum.

Horizontal shock testing table can be used to evaluate shock resistance ability of warship equipments. Based on this theory, the level of flexible plate oriented shock testing platform is raised. Using the finite element method, the output waveform of the testing platform and the stress distribution of the flexible plate are analyzed in this paper. It can be concluded that flexible plate can be used to store elastic potential energy during the impact and have a certain impact on test waveforms. Theoretical maximum displacement of the platform body is 94mm, the calculated value is 89.5mm, decrease by 4. 8%; theoretical maximum speed of the platform body is 4m/s, the calculated value is 3.93m/s, reducing to1.75%; theoretical, the value of positive wave peak acceleration of platform body is 571m/s2, the calculated value is 532 m/s2, decrease by 6.8%; theoretical platform body negative wave peak acceleration values is 175m/s2, the calculated value of 183 m/s2, an increase of 4.6%. The research shows that flexible plate as a guide device can meet the impact test table for error waveform requirements..

Orientation is one of the important elements of objects that can influence visual processing. In this study, we examined whether changes in orientation could be detected automatically under unattended condition. Visual mismatch negativity (vMMN) was used to analyze this processing. In addition, we investigated the underlying neural oscillatory activity. Non-phase-locked spectral power was used to explore the specific frequency related to unexpected changes in orientation. The experiment consisted of standard (0° arrows) and deviant (90°/270° arrows) stimuli. Compared with standard stimuli, deviant stimuli elicited a larger N170 component (negative wave approximately 170 ms after the stimuli started) and a smaller P2 component (positive wave approximately 200 ms after the stimuli started). Furthermore, vMMN was obtained by subtracting the event-related potential (ERP) waveforms in response to standard stimuli from those elicited in response to deviant stimuli. According to the time-frequency analysis, deviant stimuli elicited enhanced band power compared with standard stimuli in the delta and theta bands. Compared with previous studies, we concluded that theta activity plays an important role in the generation of the vMMN induced by changes in orientation.

Background: The depth of an arrhythmic focus is a major determinant of ablation procedural outcome. This study examined the relationship between the morphology of unipolar potentials and the depth and horizontal distance to activation foci. Methods: Unipolar left ventricular epicardial mapping was performed in 7 open-chest dogs, using silicon sheets with 12 unipolar electrodes 1 mm apart, during bipolar pacing from an octopolar plunge electrode with 1-mm interelectrode spacing. The morphology of the unipolar electrograms was classified as QS, rS, qrS, qRS, rsr’S, or rsR’S. Results: A QS complex was recorded immediately above a subepicardial or mid-myocardial pacing site. An rS complex was recorded away from a subepicardial pacing site. A positive wave originating from a down sloping deflection (R-in-QR) such as r wave in qrS, R wave in qRS, r′ wave in rsr’S or R′ wave in rsR’S complexes was observed when the recording was above a deep myocardial pacing site or away from a mid-myocardial pacing site. The amplitude of negative wave immediately before R-in-QR (Q-in-QR) was inversely correlated with the horizontal (R=−0.40; P

To determine the effect of glaucoma on the multifocal electroretinograms (ERGs) (mfERGs) elicited by low-frequency stimuli.Forty-four patients with open-angle glaucoma and 15 normal subjects were studied. The stimulus frequency was 6.25 Hz, and the stimulus was a circle with a 6.8° radius that was centered on the fovea (center). MfERGs were also elicited by a quarter of an annulus placed around the macula (superior/temporal; inferior/temporal; superior/nasal; and inferior/nasal quadrants). The radius of the inner border of the annulus was 6.8° and that of the outer border was 20°. The actual sensitivity was determined by standard automated perimetry. The thickness of the ganglion cell complex (GCC) was measured by optical coherence tomography.The mfERGs consisted of a negative wave (N1) followed by a positive wave (P1), and followed by a slow negative wave (N2). There were no significant differences in the response densities of N1 and P1 between the normal control and glaucomatous eyes in any areas. The N2 response density was significantly reduced with the severity of glaucoma in the center. There was a significant reduction even at an early stage of glaucoma compared to control values. In the center, the N2 response density was significantly correlated with the GCC thickness and mean sensitivity. However, in other stimulus areas, there was no significant reduction of any components of the mfERGs.These results suggest that the N2 component of the slow-sequence mfERGs is affected by glaucoma in the central retinal area. Regional variations in the contribution of the retinal ganglion cell activity to the N2 should be considered when examining the mfERGs in glaucoma patients.

This paper establishes the current state of the art in the subject of iceberg and bergy bit motion during interaction and impact with offshore structures. Our particular interest in the present case is the influence of hydrodynamic interaction on change in velocity as small ice masses approach a larger structure in open water. Iceberg impacts are a design driver for structures located in offshore regions subject to drifting glacial ice. It is found that although many studies note that near-field effects influence the velocity and trajectory of drifting bergs prior to impact, the understanding of near-field hydrodynamic effects such as negative wave drift force, fluid cushioning, shadowing, reduction in impact velocity, and hydrodynamic damping, is incomplete. These effects are more obvious for small ice masses and bergy bits and although they have been identified qualitatively, there is very little quantitative information available. The inability to properly account for these phenomena generally leads to overestimation in impact velocity and consequently input impact energy. Better understanding of hydrodynamic interaction between small icebergs and offshore structures in very close proximity could improve load predictions by improving the estimation of input energy.

To investigate whether cold thermal cutaneous stimulation evokes reproducible CEPs from the trigeminal territory and may prove a reliable diagnostic tool in facial neuropathic pain. A novel micro-Peltier element device able to cool the skin at −300°C/s was used to record CEPs from the trigeminal territory (V1 and V2–V3) in 15 healthy participants and compared them to LEPs from the same sites. To assess the clinical usefulness, we performed LEPs and CEPs in three patients suffering from facial neuropathic pain due to different conditions (PHN, TISN and CPSP). CEPs were observed in all healthy subjects from both sites of stimulation, with a biphasic complex maximal at the vertex (Cz), peaking 170–290 ms after stimulus onset, preceded by a negative wave over temporal areas contralateral to the stimulated site. Unlike LEPs, perioral cold stimulation did not yield shorter latency and larger amplitude CEPs than supraorbital stimulation. The patient with CPSP had suppressed CEPs and partially spared LEPs from the affected side. No significant differences were found in the other clinical conditions. Cold thermal cutaneous stimulation elicits clear CEPs. The latencies and magnitudes of CEPs response seem not to be function of the site of facial stimulation. CEPs are a useful diagnostic tool to disclose the cold pathway impairment in patients with cold allodynia.

We consider a recently proposed model by Armbruster et al. (2011) [2] for supply chains with finite buffers. The continuous model is based on a scalar conservation law and discontinuous flux function. A suitable reformulation of the model is introduced and studied analytically. The latter include waves with infinite negative wave speed. Using wave-front tracking, existence of solutions is obtained for supply chains and sequences of supply chains. Numerical results are presented.

Strategy use is a mental operation which aims directly at its target. In order to investigate brain activity during mental arithmetic strategies using, subtraction answers-discrimination tasks were used through 8 healthy subjects with the Event-related Potentials (ERPs) technique. The results showed: (1) The principal components of ERP were: N1, P1, P2, P300 and N400. (2) At the F3, C3 point, stage 4 induced more negative wave than stage 1; At F4, C4, P3 and P4 point, stage 4 induced more positive wave than stage1. (3) Activation of brain areas mainly included Temporal lobe, Prefrontal cortex and Parietooccipital. (4) With the subjects gradually skilled in using strategies, activated brain region gradually moved from back to front; meanwhile the right side had higher active level than the left of brain. Further exploration need to describe more detailed brain potentials during mental arithmetic strategies using in other conditions.

We investigated whether speakers can use an internal channel to monitor their speech for taboo utterances and prevent these from being spoken aloud. Therefore event-related potentials were measured while participants carried out the SLIP task. In this task, speech errors were elicited that could either result in taboo words (taboo-eliciting trials) or neutral words (neutral-eliciting trials). In taboo-eliciting trials, there was an augmented negative wave around 600 ms after the pronunciation cue even though there were no overt errors. This component has previously been interpreted as reflecting conflict. These results indicate that taboo utterances can indeed be detected and corrected internally.

SUMMARY The purpose of this study was to investigate a potential relation between the K-complex(KC) and sleep spindles of non-rapid eye movement (NREM) stage II of human sleep.Using 58 electroencephalogram electrodes, plus standard electrooculogram andelectromyogram derivations for sleep staging, brain activity during undisturbedwhole-night sleep was recorded in six young adults (one of them participated twice).NREM stage II spindles (1256 fast and 345 slow) and 1131 singular generalized KCswere selected from all sleep cycles. The negative peak of the KC, the positive peak of theKC (where applicable), and the prominent negative wave peak of slow and fast spindleswere marked as events of reference. Fast Fourier transform-based time–frequencyanalysis was performed over the marked events, which showed that: (a) fast spindlesthat happen to coincide with KC are interrupted (100% of 403 cases) and in their placea slower rhythmic oscillation often (80%) appears; and (b) spindles that are usually(72% of 1131) following KCs always have a higher frequency (by 1 Hz) than both theinterrupted spindles and the individual fast spindles that are not in any way associatedwith a KC. This enhancement of spindle frequency could not be correlated to any of theKC parameters studied. The results of this study reveal a consistent interaction betweenthe KC and the sleep spindle during NREM stage II in human sleep.keywords human electroencephalogram, k-complex, non-rapid eye movementsleep, spindle

Intense brief sound evokes short-latency myogenic potentials around the eyes in humans. These potentials are named ocular vestibular-evoked myogenic potentials (OVEMP), but the origin and pathway of these responses remain unclear. To establish an animal model for OVEMP, we recorded sound-evoked potentials around the eyes using awake monkeys. Two macaque monkeys were used in the research. A pair of electrodes was attached under an eye, and each animal was made to gaze at the monitor with their eyes in a fixed position while sitting in a primate chair. When a 135-dB SPL air-conducted 500-Hz tone burst was applied, the peak latencies of the first negative and second positive waves were 10.4 msec and 13.7 msec. The peak latency of the first negative wave did not change when the frequency was changed. The threshold of the myogenic potentials at a frequency of 500 Hz was lowest among the 4 tested frequencies (500Hz, 1kHz, 2kHz and 4kHz). The contralateral amplitude to the sound stimulation was greater than the ipsilateral amplitude. Furthermore, the amplitude for an upward-gazing position was greater than that for a downward-gazing position. The characteristics of these potentials were similar to those of OVEMP in humans, suggesting that the sound-evoked myogenic potentials around the eyes in monkeys may be utilized as an animal model of OVEMP.

BACKGROUND: Viewing pictures activates the human brain in a complex manner. Stimulated brain areas can be identified by electrophysiological methods even in children. SUBJECTS AND METHOD: Event related potentials (ERP) were recorded with EEG-surface electrodes in children and adolescents who were shown pictures of increasing complexity. Pictures were categorized into morphologic features such as brightness, color and pattern as well as semantic content. Results: Presentation of comics and unstructured pictures, similar in color and brightness, revealed ERP with nearly identical early components (P 100). However, substantial differences were found in frontocentral brain areas. A negative wave at approximately 400 ms was recorded only when comics were shown. CONCLUSIONS: Semantic scenes provoked significant different ERP, which indicate an early involvement of complex neuronal networks. These results could be applied in the research of pediatric cognitive disturbances.

The present study investigated whether the human brain is sensitive to valence differences in emotionally negative stimuli by recording event-related potentials (ERPs) for extremely negative (EN), moderately negative (MN), and neutral pictures while subjects perform a standard/deviant categorization task, irrespective of the emotional valence of the deviants. Using the same design, we also investigated the sensitivity of the human brain to valence differences in emotionally positive stimuli. Experiment 1 showed that EN stimuli elicited more negative deflections than MN stimuli in the early P2 and N2, later P3, and slow negative wave (SNW) components. In contrast, there were no differences in amplitude or latency in these components during the extremely positive (EP) and moderately positive (MP) conditions of Experiment 2. This suggests that humans are only sensitive to valence differences in negative stimuli, and that these negative valences could be processed differentially throughout the information processing stream even when individuals are highly engaged in a non-emotional task.

The aim of this study was to compare left atrial appendage (LAA) functions by Doppler tissue imaging (DTI) before and after percutaneous balloon mitral valvuloplasty (PBMV). Twenty patients with symptomatic rheumatic mitral stenosis who underwent PBMV were included in this study. LAA functions were measured before and after PBMV. To determine LAA functions, LAA late filling (LAALF) velocity, LAA late emptying (LAALE) velocity, and area change of LAA percent were measured. In the DTI records, the first positive wave identical to the LAALE wave after the P wave was accepted as LAA late systolic wave, and the second negative wave identical to the LAALF flow was accepted as late diastolic wave. There was no difference in LAALF velocity and area change of LAA percent after PBMV. LAALE velocity increased after PBMV compared with baseline ( P = .005). Late emptying, systolic, and diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline ( P = .023, P = .002, and P = .002, respectively). LAALE velocity measured by standard Doppler was increased after PBMV compared with baseline ( P = .005), but there was no change in area change of LAA percent or LAALF. Spontaneous echocontrast was present in 7 of the 20 patients before procedure. It completely disappeared (4 patients) or decreased (3 patients) after procedure. In patients with spontaneous echocontrast, LAALE and late emptying, systolic, and diastolic wave values measured by DTI were found to be increased after PBMV compared with baseline. Our results suggest that PBMV improves LAA functions and, thereby, may have a favorable influence on future thromboembolic complications.

Recent studies have suggested that a higher mobility of the fossa ovalis membrane (FOM) may be associated with an increased risk for stroke in patients with patent foramen ovale (PFO). The current study analyzed whether Doppler tissue echocardiography is useful for quantitation of FOM motion velocities.FOM dynamics were prospectively studied in 107 consecutive patients (average age 50.7 +/- 15.3 years, 48 men) with in sinus rhythm who underwent transesophageal echocardiography for various indications. With pulsed wave Doppler tissue echocardiography interrogation, a characteristic quadrophasic signal was recorded in all patients, consisting of a positive wave toward the left atrium (A-wave) at late diastole, followed by a negative wave (B-wave) toward the right atrium, a pronounced, again positive wave during midsystole (C-wave), and a final negative wave (D-wave).Peak velocities of A-wave, B-wave, C-wave, and D-wave were 0.08 +/- 0.02 m/s, 0.11 +/- 0.05 m/s, 0.17 +/- 0.07 m/s, and 0.14 +/- 0.06 m/s, respectively. In 21 of 107 (19.6%) patients, PFO was detected. Patients with PFO had significantly higher C-wave and D-wave peak velocities compared with the 86 patients without PFO (0.23 +/- 0.10 m/s vs 0.15 +/- 0.05 m/s, P.001 and 0.16 +/- 0.07 m/s vs 0.12 +/- 0.06 m/s, P = .04, respectively).Assessment of FOM dynamics using Doppler tissue echocardiography is feasible. It allows definition of a characteristic quadrophasic FOM motion pattern, thereby providing new insights into the physiology of FOM mobility. Patients with PFO were found to have increased FOM mobility compared with patients without PFO.

It has been hypothesized that zero vs. nonzero operands in single-digit multiplication problems invoke distinct solution strategies. We studied such problems in an implicit production task with event-related brain potentials (ERPs) recorded from 61 scalp positions in 18 participants. The topography of a slow negative wave, which accompanied the implicit production of the multiplication result, varied with problem type. In comparison to small problems, larger problems evoked a stronger negativity over fronto-central and right temporal sites, and zero problems evoked a left anterior negativity. These topographic differences indicate not only that zero and small nonzero problems are solved by means of distinct strategies-most likely rule application vs. fact retrieval-but also that larger, less practiced problems invoke other processes than pure fact retrieval. Moreover, ERPs showed a positive deflection around 450 ms with a centro-parietal topography (P300), whose amplitude reflected differences in anticipated problem difficulty.

Recent studies report that some children with dyslexia have impaired visual processing, specifically in the fast-processing magnocellular pathway. The objective was to study the effect of varying luminance and temporal and spatial frequency on the latency and amplitude of the visual evoked potentials (VEPs) in normal and dyslexic Egyptian children who speak Arabic (a right-left reading and writing system). VEPs were recorded in 52 dyslexic and 41 normal children in the fourth grade using a black and white checkerboard pattern with different checkerboard sizes and different rates of stimuli at high- and low-contrast media. The peak of the major positive wave component (P100) of each waveform and the trough of the previous major negative wave component were identified, and the peak-to-trough amplitude was measured. The latency and amplitude of VEPs in response to different experimental conditions showed significant shortening of P100 latency under high-contrast media and under low spatial frequency in children with dyslexia compared with normal readers. Furthermore, dyslexia children showed prolonged P100 latency in response to high spatial frequency stimulation compared with the low spatial frequency (P=0.003) and significantly higher N1-P1 amplitude under high-contrast media compared with low-contrast media (P=0.02), whilst no such changes were observed in normal readers. These results are suggestive of deficiency within the parvocellular pathway rather than the magnocellular pathway. As reading apparently places demands primarily on the ability to discriminate fine details, which is to say, on the parvocellular system, we suggested that deficiency in this system, at least in Arabic speaking children, could be a predisposing factor in dyslexia.

To study the effects of training on reactivity and event-related potentials a complex attentional shifting test involving reaction time was administered (Test 1) to 24 healthy, young students. After five days, 12 subjects were tested with the same procedure (Test 2) without training (Untrained Subjects) while 12 repeated the test at the fifth day after four days of training (Trained Subjects). During Tests 1 and 2, event-related potentials were recorded by electroencephalogram. The task consisted of each subject responding to a stimulus of a letter appearing in the centre of a geometric figure on the screen of a computer monitor. In the prestimulus period black points were drawn and crowded randomly into a zone of the screen. The geometric figure and the letter were shown in the centre of the crowding. There were two letters and four geometric figures randomly combined in different ways. The subject had to press different keys of the computer keyboard when specific combinations appeared. The averaged event-related potentials were characterized by a negative wave with a close relationship to selective attention before the onset of the stimulus of a geometric figure followed by letters. After the stimulus onset, a P3 complex was recorded. Trained subjects were no different from untrained subjects in Test 1, while in Test 2 they had a shorter reaction time, an earlier peak of the selective attention related wave and P3, and a higher amplitude for the P3 complex. These measures and the correlations between them can be considered an index of the training effect. Thus, these tests could be used for evaluation of the attentional style and its modification with training.

Sixteen subjects were instructed to discriminate whether the spatial locations of two visual stimuli presented in sequence were identical and event-related potentials (ERPs) were recorded from their scalps. The first and the second stimuli were presented in the same location in condition 1, but were in different locations in condition 2. ERP components of P100, N150, late positive component (LPC) and slow negative wave (SNW) were recorded in condition 1; in condition 2, N150 was enhanced and N270 was elicited before LPC. N150, N270 and SNW were all mainly distributed bilaterally over P3, P4, Pz, O1, O2, and Oz. N270 represents the brain activity for processing spatial discrepancy. There are several specialized brain areas involved in the generation of the N270.

The museum will be built on a landmass retained by a vertical seawall with varying top elevations, protected by four detached breakwaters. One of the main challenges of the study was to limit wave overtopping and negative wave pressures on the seawall while minimizing the visual impact of the detached breakwaters. Empirical approaches and a series of numerical and 2D/3D physical models were used to validate and optimize the design of the detached breakwaters, while still meeting the project requirements in regards to wave loads and wave overtopping discharges.

This study used Event-related Potentials (ERPs) to examine the difference between three issue types (related, foil, and unrelated issues) and two reaction types (honesty and deception reaction). This was a subject-in design. Two sets of data were collected. First, the behavior data showed that the reaction time of the deception was 200ms slower than that of honesty, and the decreasing order of the reaction time on three designed issue types was foil issues, unrelated issues, and related issues. Second, the EEG data showed that related issues produce the most significant ERPs effect; the obvious wave separation of honesty reaction was between 300ms to 800ms versus 200ms to 500ms in experiment of deception; the deception reaction could evoke distinct P300, which was most obvious in left parietal lobes such as FC3, C3, CP3, P3; P3 was more sensitive in the time window of 200ms to 400ms, honesty reaction evoked obvious positive wave whereas deception evoked negative wave. In conclusion, the reaction time of deception was significantly slower than honesty. Moreover, deception evoked the obvious P300 effect. Based on the waveform evoked by different issue types, left parietal lobe waveform could be used as judgement of honesty or deception, and the correlation between suspect and the case could be decided.

Background: Multifocal electroretinogram (mfERG) is a device for recording the physiological response of multiple retinal areas in short time. Using this technique enables us to detect the spatial extent and severity of the retinal damage. Objectives: In this study,we aimed to assess the topographic properties of mfERG in normal subjects to use it as a basic data to evaluate eye disease. Methods: We recorded mfERG from 20 eyes of 20 normal subjects. We measured amplitude and latency of recorded waves. We compared between amplitude of these waves between different retinal areas and the same for latency. Results: We found mfERG responses in the form of waves, every wave consists of negative wave (N1) followed by positive wave (P1). The amplitude of N1 wave and amplitude of P1 were largest at the fovea and decreased toward periphery. The latency of N1 and P1 were shorter in upper retina than lower retina. The N1 amplitude and P1 amplitude was larger in upper retina than lower retina, which reflex functional superiority of upper retina. There was no statistical difference between nasal and temporal retina in the amplitude and latency.Conclusion: Multi-focal ERG would be useful for objective examination of the retinal function.

Background: The click and tone-evoked auditory brainstem responses are widely used in clinical practice due to their consistency and predictability. More recently, the speech-evoked responses have been used to evaluate subcortical processing of complex signals, not revealed by responses to clicks and tones. Aims: Disyllable stimuli corresponding to familiar words can induce a pattern of voltage fluctuations in the brain stem resulting in a familiar waveform, and they can yield better information about brain stem nuclei along the ascending central auditory pathway. Materials and Methods: We describe a new method with the use of the disyllable word baba corresponding to English daddy that is commonly used in many other ethnic languages spanning from West Africa to the Eastern Mediterranean all the way to the East Asia. Results: This method was applied in 20 young adults institutionally diagnosed as dyslexic (10 subjects) or light dyslexic (10 subjects) who were matched with 20 sex, age, education, hearing sensitivity, and IQ-matched normal subjects. The absolute peak latencies of the negative wave C and the interpeak latencies of A-C elicited by verbal stimuli baba were found to be significantly increased in the dyslexic group in comparison with the control group. Conclusions: The method is easy and helpful to diagnose abnormalities affecting the auditory pathway, to identify subjects with early perception and cortical representation abnormalities, and to apply the suitable therapeutic and rehabilitation management.

Motor evoked potentials by magnetic stimulation is less invasive and causes no pain as opposed to high current electric stimulation. However, the distribution of the magnetic field generated by the round coil has not been fully studied. In this report, we mapped the extent of the magnetic induction flux density, and then the evoked potentials from the spinal cord were investigated by transcranial magnetic stimulation. We also examined the origin of the evoked potentials obtained by the magnetic stimulation. The following results were obtained. The magnetic induction flux density was at its maximum at the edge of the coil. The potentials consisted of a first negative wave and subsequent multiphasic waves. The first negative wave was similar to a response of the subcorticospinal tract in the lower brain stem, while the subsequent multiphasic waves were similar to those of the pyramidal tract. Although magnetic stimulation has certain advantages over electric stimulation, several problems remain to be solved for the monitoring of motor functions in the clinical settings.

The cognitive incongruity paradigm consists in presenting congruous or incongruous factual information to subjects, who are instructed to judge the truth of this information by comparing it with the factual knowledge stored in their semantic long-term memory. The factual information tested was whether a city presented after the name of a country, belongs (congruity) or not (incongruity) to that country. Results revealed that the recognition of incongruous factual information is characterized by a negative wave (N400), while the processing of congruous factual knowledge is characterized by a positive wave (P300) about 600 ms post-stimulus. In addition, these two components were sensitive to subject performance and subject confidence levels. The neurophysiological brain pattern observed during the cognitive incongruity paradigm reveals that the N400 and P300 are jointly affected by the task and reveals that the recognition processes of factual knowledge.

This work describes the characteristics of a tsunami with an initial negative wave in the Pacific Ocean. These tsunamis fall into two classes; one class is produced by strong earthquakes and the other by earthquakes of moderate size. The relationship between the run-up probability occurrence is determined for both classes of tsunami and the mechanisms by which the tsunamis are generated is considered with reference to the keyboard model of tsunamigenic earthquakes. Tsunamis in the Arica region of northern Chile were analysed in more detail and these analyses suggest that a catastrophic tsunami is likely to occur in the Arica region in the next 10–20 years.

Dambreak flows in a smooth, rectangular channel are considered. In all experiments, the abrupt rupture on an absolutely dry tailwater channel was modelled. The effect of bottom slope up to 50% is analyzed, and the results are compared with those pertaining for the horizontal channel. The positive and negative wave fronts are determined based on the characteristic equations. Also, the drying front is computed and the effect of viscosity is analyzed. The experiments are in agreement with the observations collected with a specially designed Video system. The positive wave front is found to tend towards a pseudo-uniform flow for large locations downstream of the dam section. The characteristics of the dambreak waves are then described, including the maximum wave height, and a generalized wave profile. The decay of maximum wave height is related to a combined parameter that includes the position, the bottom slope and the initial water depth. Further, the velocities in the wave body are determined and the veloc...