Pseudo channel:time embedding for motor imagery decoding

Motor imagery(MI)based electroencephalogram(EEG)represents a frontier in enabling direct neural control of external devices and advancing neural rehabilitation.This study introduces a novel time embedding technique,termed traveling-wave based time embedding,utilized as a pseudo channel to enhance the decoding accuracy of MI-EEG signals across various neural network architectures.Unlike traditional neural network methods that fail to account for the temporal dynamics in MI-EEG in individual difference,our approach captures time-related changes for different participants based on a priori knowledge.Through extensive experimentation with multiple participants,we demonstrate that this method not only improves classification accuracy but also exhibits greater adaptability to individual differences compared to position encoding used in Transformer architecture.Significantly,our results reveal that traveling-wave based time embedding crucially enhances decoding accuracy,particularly for participants typically considered“EEG-illiteracy”.As a novel direction in EEG research,the traveling-wave based time embedding not only offers fresh insights for neural network decoding strategies but also expands new avenues for research into attention mechanisms in neuroscience and a deeper understanding of EEG signals.

Effects of spinal cord stimulation on cerebrovascular flow: role of sym-pathetic and parasympathetic innervations

Objective Cervical spinal cord stimulation （SCS） has been found to augment cerebral blood flow （CBF） in a number of animal models. However, the effective use of SCS is hampered by a lack of understanding of its mechanism（s） of action. In this paper, we focus on the sympathetic and parasympathetic effects of SCS on CBF. Method SpragueDawley rats were selected for the experimental series. The animals were divided into 5 groups to underwent SCS and laser Doppler flowmeter （LDF） recordings. Control group, the animal underwent SCS and LDF recordings without any surgery of the nerve fibers and ganglia. V 1 group, the animal underwent bilateral resection of the nasociliary and post-ganglionic parasympathetic nerve fibbers. SCG group, the animal underwent bilateral resection of supper cervical ganglion. V 1 ＋ SCG group, the animal underwent both surgeries as V1- and SCG-group animals did. Sham group, the animal underwent the carotid manipulation with blunt-tipped forceps as well as the dissection of nasociliary and post-ganglionic parasympathetic nerve fibers around the ethmoidal foramen, but without cutting any nerves. Results During the SCS, the LDF was no statistical difference between the V 1 or SCG group and the control group. Yet, the effects of SCS on CBF are completely abolished in V1＋ SCG group. Conclusions Surgical interruption of both the parasympathetic and sympathetic pathways has the contradict effect on SCS-induced CBF augmentation.

Effects of Electroacupuncture at the Conception Vessel on Proliferation and Differentiation of Nerve Stem Cells in the Inferior Zone of the Lateral Ventricle in Cerebral Ischemia Rats

Objective： To observe the effects of electroacupuncture （EA） at the Conception Vessel on proliferation and differentiation of the nerve stem cells in the inferior zone of the lateral ventricle in cerebral ischemia rats. Methods： The model rats were prepared by occlusion of the middle cerebral artery for 2 hours and then by reperfusion. They were randomly divided into two groups： a control group and an EA group. Changes in differentiation and proliferation of the nerve stem cells were observed 7, 14 and 28 days after successful modeling. Results： As compared with the 7-day control group （C-7d group）, there was no significant difference （P〉0.05） in the numbers of 5-bromodeoxyuridine （Brdu） positive cells, Brdu/GFAP, Brdu/Nestin and Brdu/Nse double-labeled cells in the inferior zone of the lateral ventricle in the EA group 7 days after modeling. However, in the 14-day EA group （R-14d group） and the 28-day EA group （R-28d group）, the numbers of Brdu positive cells and Brdu/GFAE Brdu/Nestin, Brdu/Nse double-labeled cells significantly increased as compared respectively with the 14-day control （C-14d group） and the 28-day control （C-28d） group （P〈0.05 or P〈0.01）. Conclusions： EA at the Conception Vessel promotes differentiation and proliferation of the nerve stem cells in the inferior zone of the lateral ventricle in the cerebral ischemia rats, and may stimulate differentiation of the proliferous nerve stem cells towards the astrocvtes.

Primary hepatic carcinoid:A case report and literature review

Carcinoids are tumors derived from neuroendocrine cells and often produce functional peptide hormones.Approximately 54.5% arise in the gastrointestinal tract and frequently metastasize to the liver.Primary hepatic carcinoid tumors(PHCT) are extremely rare;only 95 cases have been reported.A 65-year-old man came to our attention due to occasional ultrasound findings in absence of clinical manifestations.His previous medical history,since 2003,included an echotomography of the dishomogeneous parenchymal area but no focal lesions.A computed tomography scan performed in 2005 showed an enhanced pseudonodular-like lesion of about 2 cm.Cholangio-magnetic resonance imaging identified the lesion as a possible cholangiocarcinoma.No positive findings were obtained with positron emission tomography.Histology suggested a secondary localization in the liver caused by a low-grade malignant neuroendocrine tumor.Immunohistochemistry was positive for anti chromogranin antibodies,Ki67 antibodies and synaptophysin.Octreoscan scintigraphy indicated intense activity in the lesion.Endoscopic investigations were performed to exclude the presence of extrahepatic neoplasms.Diagnosis of PHCT was established.The patient underwent left hepatectomy,followed by hormone therapy with sandostatine LAR.Two months after surgery he had a lymph nodal relapse along the celiac trunk and caudate lobe,which was histologically confirmed.The postoperative clinical course was uneventful,with a negative follow-up for hematochemical,clinical and radiological investigations at 18 mo post-surgery.Diagnosis of PHCT is based principally on the histopathological confi rmation of a carcinoid tumor and the exclusion of a non-hepatic primary tumor.Surgical resection is the recommended primary treatment for PHCT.Recurrence rate and survival rate in patients treated with resection were 18% and 74%,respectively.

EFFECT OF ELECTROACUPUNCTURE ON DISCHARGES OF PAIN-REACTION NEURONS IN CAUDATE NUCLEUS AND PARAFACICULAR NUCLEUS IN RATS WITH CEREBRAL HEMORRHAGE

Objective: To study the bidirectional adjustment effe ct of ele ctroacupuncture (E A) on the electrical activities of neurons in caudate nucleus (CN) and parafasci cular nucleus (PFN) in rats with acute cerebral hemorrhage (ACH). Methods: ① 32 male Wistar rats were evenly randomize d into normal, EA+normal, model and model +EA groups for observing the effect of EA on pain reaction; ② another 40 male Wi star rats were equally randomized into control, saline, model and EA groups for comparing the effects of EA on discharges of pain-reaction neurons in CN and P FN . ACH model was established by intracerebral injection of the rat’s own arteria l blood sample (30μL) into CN and PFN. Pain reaction was tested by using tail -flicking (TF) reflex induced by radiation-heat irradiation. Extra-cellular d ischarges of neurons of CN and PFN were recorded by using glass micropipettes. E A (1 V, 15 Hz and duration of 10 min) was applied to "Baihui"(百会 GV 20) and "Taiyang" (太阳 EX-HN 5). Frequency of discharges of CN and PFN neurons was calculated be fore and after intracerebral injection of blood sample, heat nociceptive stimula tion and EA respectively. Results: Compared with con trol group and pre-EA in the same group, TF latency (TFL) values of normal rats increased significantly; compared w ith pre-injection of blood, TFL of model group also increased pronouncedly ( P<0.0 1). In comparison with model group, TFL values of EA group decreased significant ly (P<0.01), indicating that EA of GV 20 and EX-HN 5 could suppress ACH induced increase of TFL. In ACH rats, the latency of pain-excitement response of disch ar ges of CN and PFN neurons increased significantly, while the net increase values of pain-excitement response decreased significantly in model group (P< 0.05～0.01 ), the duration of pain-inhibitory response and the net decrease values of dis ch arges of CN and PFN neurons increased clearly. Comparison between model and EA groups showed that the latency values of the pain-excitement reaction of disch ar ges of CN and PFN neurons in EA group were significantly lower than those in mod el group (P<0.01), while the net increase values of discharges of CN and PFN neu rons in EA group were considerable higher than those in model group (P< 0.01); th e latency and net decrease values of pain-inhibitory CN and PFN neurons in EA gr oup were clearly lower than those in model group. It indicated that EA could pro l ong the latency of pain-excitatory reaction and shorten the duration of pain-i nhi bitory reactions of the neurons induced by cerebral hemorrhage and raise the exc itement degree of CN and PFN neurons. Conclusion: EA can reduce the excitability of pain-excitement neurons (PEN) and lower the inhibitory degree of pain -inhibitory neurons (PIN) in both CN and PFN, an d thus possesses a bidirectional regulation effect on cerebral hemorrhage-induced c hanges of the electrical activities of neurons in both CN and PFN.

Independent Source Separation of Multichannel Electroencephalogram Based on Neural Network

A neural network method for independent source separation (ISS) of multichannel electroencephalogram (EEG) is proposed in this paper.Using the denoising function of wavelet multiscale decomposition,the high-frequency noises are removed from the original (raw) EEGs.Then the multichannel EEGs are treated as the weighted mixtures and the expression of weight vector is obtained by seeking the local extrema of the fourth-order cumulants (i.e.kurtosis coefficients) of the mixtures.After these process steps,the weighted mixtures are used as the input of neural network,so the independent source of EEGs can be separated one by one.The experimental results show that our method is effective for ISS of multichannel EEGs.

告别硅时代——电脑今后向何处去？

虽然事实上您今天买到的电脑明天就会过时，这一趋势却并不是什么新鲜的事情。早在1965年，后来创建了英特尔公司的戈登·穆尔就预言，电路板上的晶体管的数量在1975年以前将每18个月增加一倍。这一惊人预测直到今天仍是正确的。

Seizures dynamics in a neural field model of cortical-thalamic circuitry

The focus of this study is to explore the mechanisms during seizure behavior using a physiologically motivated by corticothalamic circuity. The model is based on the assumption that, the inhibitory projects from thalamus reticular nucleus(TRN) to specific relay nuclei(SRN) are mediated by GABAA and GABAB receptors which react different time scales in synaptic transmission.Secondly, we include the effects of slow modulation on the threshold current of TRN population that were found to generate bursting behavior. Our model can reproduce healthy and pathological dynamics including wake, spindle, deep sleep, and also seizure states. In addition, contour maps are used to explore the transition of different activity states. It is worthy to point out seizure duration is significantly affected by a time-varying delay as illustrated in our numerical simulation. Finally, a reduced model ignoring the cerebral cortex mass can also capture the feature of spike wave discharge as generated in the full network.