• Annals of Clinical Neurophysiology
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• v.14 no.2
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• pp.59-63
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• 2012

Epilepsy has continued to provide challenges to epileptologists, as a significant proportion of patients continue to suffer from seizures despite medical and surgical treatments. Deep brain stimulation (DBS) has emerged as a new therapeutic modality that has the potential to improve quality of life and occasionally be curative for patients with medically refractory epilepsy who are not surgical candidates. Several groups have used DBS in drug-resistant epilepsy cases for which resective surgery cannot be applied. The promising subcortical brain structures are anterior and centromedian nucleus of the thalamus, subthalamic nucleus, and other nuclei to treat epilepsy in light of previous clinical and experimental data. Recently two randomized trials of neurostimulation for controlling refractory epilepsy employed the strategies to stimulate electrodes placed on both anterior thalamic nuclei or near seizure foci in response to electroencephalographically detected epileptiform activity. However, the more large-scale, long-term clinical trials which elucidates optimal stimulation parameters, ideal selection criteria for epilepsy DBS should be performed before long. In order to continue to advance the frontier of this field, it is imperative to have a good grasp of the current body of knowledge.

• Applied Microscopy
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• v.18 no.2
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• pp.177-186
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• 1988

Degeneration of the axon terminals of mamillo-thalamic tract following the electrical coagulation of mamillary body is well known. In this study, the author investigated the ultrastructural alterations of neuropil components, initiated by terminal degenerations. Rats weighing approximately 250 gm were fixed on the stereotaxic instrument(David Kopf Inc., Heavy duty model), and NE 300 active electrode(Rhodes Med. Instr. Inc.) was introduced to the mamillary position of anterior 3.8 mm, lateral 0.5 mm, height 3.8 mm and lateral angle of $23^{\circ}$ according to De Groot's Atlas. Electric current of 20 mA was applied during 1 minute between active and inactive electrodes with Radio Frequency Lesion Generator(RFG 4, Radionics Inc.). Two hours, 2 days, 1 week and 2 weeks following the electrical coagulation of mamillary body, ipsilateral anterior thalamic nucleus was fixed in 1% glutaraldehyde-l% paraformaldehyde and 2% osmium tetroxide, embedded in Araldite mixture, cutted with LKB ultra tome V, stained with uranyl acetate-lead citrate and observed with JEOL 100 CX electron microscope. Observed results were as follows; 1. Degenerated mamillo-thalamic synapses were observed to form asymmetric axospinous or axo-dendritic types. 2. Terminal degeneration was not easily discernible at 2 hours interval after mamillary lesion, but following 2 days the terminal degeneration was apparent. 3. Postsynaptic spines, dendrites and even their cell bodies show edematic changes caused by the degeneration of postsynaptic counterpart. 4. Astrocytic territories, including perivascular processes forming glial limitans of blood-brain barrier, exhibit remarkable expansion. 5. Oligoglia and astroglia are actively engaged in the removal of degenerated elements. 6. Active forms of microglia were increased. 7. The observed results may represent typical ultrastructural alteration pattern within neuropil following the degeneration of certain input axon terminals.

• Journal of Acupuncture Research
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• v.19 no.1
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• pp.159-174
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• 2002

Objective : The meridian theory in oriental medicine explains that each acu-point has a characteristic functional effect. It will be supposed that an acupuncture stimulation on different acu-point evokes different activation on different areas in the central nervous system(CNS) according to the meridian theory. On this supposition, our group tried the semi-quantitative [14C]2-deoxyglucose([14C]2-DG) autoradiography on the acupuncture stimulation to the hindlimb acu-points of Sprague-Dawley rats. Methods : A venous catheter for the intravenous administration of isotope was equipped in the right external jugular vein on 3 days prior to the [14C]2-DG study. On the day of the study, two acupuncture needles were inserted into the ST36(Zusanli) or LR3(Taichong) on the left hindlimb. Electro-acupuncture stimulation (2 Hz, 5 ms, 1~3 mA, 15 minutes) started just before the i.v. injection of [14C]2-DG ($25{\mu}Ci/rat$). The brain and the spinal cord were removed and processed for the [14C] 2-DG autoradiography. Results : The EA stimulation on ST36 reveals over 120% metaboilc activation in Arcuate nucleus, Anterior pretectal nucleus, Dorsal cochlear nucleus, Interposed cerebellar nucleus, and Nucleus of Darkschewitsch. The EA stimulation on LR3 reveals over 120% metaboilc activation in Lateral habenula nucleus, Medial vestibular nucleus, Ventromedial thalamic nucleus, Anteroventral thalamic nucleus, Anterior cingulate cortex, Dentate gyrus, Antero cortical amygdaloid nucleus, Anterior pretectal nucleus, and Dorsal tegmental nucleus compared with the non EA stimulation control group. Conclusion : These results demonstrate that the different acu-points evoke the different activations in brain areas. And with this functional brain mapping study, a new scientific elucidation for the basis of the acupuncture-meridian theory in oriental medicine through differences of activated area in CNS according to the each acupuncture point.

• Animal cells and systems
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• v.2 no.1
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• pp.71-80
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• 1998

Glutamate dehydrogenase (GDH) is one of the main enzymes involved in the formation and metabolism of the neurotransmitter glutamate. In the present study, we investigated the distribution of the GDH-immunoreactive cells in the rat brain using monoclonal antibodies against bovine brain GDH isoprotein. GDH-immunoreactive cell were distributed in the basal ganglia, thalamus and the nuclei belong to substantia innominata, and its connecting area, subthalamic nucleus, zona incerta, and substantia niqra. We could see GDH-immunoreactive cells in the hippocampus, septal nuclei associated with the limbic system, the anterior thalamic nuclei connecting between the hypothalamus and limbic system, and its associated structures, amygdaloid nuclear complex, the dorsal raphe and median raphe nuclei and the reticular formation of the midbrain. The GDH-immunoreactive cells were shown in the pyramidal neurons of the cerebral cortex, the Purkinie cells of the cerebella cortex, their associated structures, ventral thalamic nuclei and the reticular thalamic nuclei that seem to function as neural conduction in the thalamus.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.11a
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• pp.140-147
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• 2002

시상은 체감각 정보를 처리하는데 있어서 매우 중요한 역할을 하는 부위이다. 본 연구는 운동장애 환자의 시상에서 뉴론의 활동 특성을 알아보기 위해 수행되었다. 그 결과 체감각으로서의 운동자극에 반응하는 뉴론이 essential tremor (ET) 환자의 nucleus ventralis intermedius (VIM)에서 발견되었다. ET 환자 뉴론의 평균 활동율(firing rate)은 Parkinson's disease (PD) 환자 보다 높았다. 또한 ET 환자의 VIM에서 운동자극에 반응하는 뉴론의 평균 활동율은 PD 환자 보다 높았다. 하지만 촉각자극(touch)에 반응하는 nucleus ventralis caudalis (VC) 뉴론의 활동율은 ET와 PD 집단간에 차가 없었다. Bursting activity를 나타내는 뉴론은 nucleus ventralis oralis anterior (VOP)에서 ET집단이 PD 집단보다 적었다. tremor cell은 VIM에서 PD 보다 ET집단이 더 적었다. 이러한 결과는 체감각 자극에 반응하는 시상 뉴론의 특성이 운동장애의 유형에 따라 서로 다르다는 것을 시사한다.

• Investigative Magnetic Resonance Imaging
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• v.19 no.1
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• pp.1-9
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• 2015

Purpose: Several morphometric studies have been performed to investigate brain abnormalities in congenitally deaf people. But no report exists concerning structural brain abnormalities in congenitally deaf adolescents. We evaluated the regional volume changes in gray matter (GM) using voxel-based morphometry (VBM) in congenitally deaf adolescents. Materials and Methods: A VBM8 methodology was applied to the T1-weighted magnetic resonance imaging (MRI) scans of eight congenitally deaf adolescents (mean age, 15.6 years) and nine adolescents with normal hearing. All MRI scans were normalized to a template and then segmented, modulated, and smoothed. Smoothed GM data were tested statistically using analysis of covariance (controlled for age, gender, and intracranial cavity volume). Results: The mean values of age, gender, total volumes of GM, and total intracranial volume did not differ between the two groups. In the auditory centers, the left anterior Heschl's gyrus and both inferior colliculi showed decreased regional GM volume in the congenitally deaf adolescents. The GM volumes of the lingual gyri, nuclei accumbens, and left posterior thalamic reticular nucleus in the midbrain were also decreased. Conclusions: The results of the present study suggest that early deprivation of auditory stimulation in congenitally deaf adolescents might have caused significant underdevelopment of the auditory cortex (left Heschl's gyrus), subcortical auditory structures (inferior colliculi), auditory gain controllers (nucleus accumbens and thalamic reticular nucleus), and multisensory integration areas (inferior colliculi and lingual gyri). These defects might be related to the absence of general auditory perception, the auditory gating system of thalamocortical transmission, and failure in the maturation of the auditory-to-limbic connection and the auditorysomatosensory-visual interconnection.

• The Journal of Korean Medicine
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• v.24 no.3
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• pp.51-64
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• 2003

Objective : This study investigated the alteration of neural activity and effect of Yanggyuksanhwa-tang (Lianggesanhuo-tang) on cerebral ischemia of rats. Methods : Considering age-related impact on cerebral ischemia, aged rats (18 months old) were used for this study. Ischemic damage was induced by the transient occlusion of bilateral common carotid arteries (BCAO) with hypotension. Yanggyuksanhwa-tang (Lianggesanhuo-tang) was administered twice a day orally. Then alterations of neural activities in the brain of aged BCAO rats were measured by the [$^{14}C$]2-deoxyglucose autoradiography method. Results : The BCAO in aged rats led to significant decrease of neural activity in the whole brain. Treatment with Yanggyuksanhwa-tang (Lianggesanhuo-tang) significantly attenuated the decrease of neural activity in the whole brain following BCAO ischemia. Treatment significantly attenuated the decrease of neural activity in the CA1, CA2, CA3, dentate gyrus of the hippocampus, activated barrel, barrel cortex, somatosensory cortex, cingulate cortex, caudate putamen, and medial septal nucleus following BCAO in aged rats. Treatment with Yanggyuksanhwa-tang (Lianggesanhuo-tang) also significantly attenuated the decrease of neural activity in the anteroventral thalamic nucleus, ventral anterior thalamic nucleus, arcuate nucleus, posterior hypothalamic area, medial mammillary nucleus, lateral periaqueductal gray, dorsal raphe nucleus, interpeduncular nucleus, median raphe nucleus, and medial pontine nucleus. Conclusion : It can be suggested that Yanggyuksanhwa-tang (Lianggesanhuo-tang) has a neuroprotecuve effect on cerebral ischemia through the control of glucose metabolic rate and cerebral blood flow.

• Journal of Korean Neurosurgical Society
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• v.47 no.5
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• pp.365-369
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• 2010

Objective : There has been inconsistency about definition of the temporal stem despite of several descriptions demonstrating its microanatomy using fiber dissection and/or diffusion tensor tractography. This study was designed to clarify three dimensional configurations of the temporal stem. Methods : The fronto-temporal regions of several formalin-fixed human cerebral hemispheres were dissected under an operating microscope using the fiber dissection technique. The consecutive coronal cuts of the dissected specimens were made to define the relationships of white matter tracts comprising the temporal stem and the subcortical gray matters (thalamus, caudate nucleus, amygdala) with inferior limiting (circular) sulcus of insula. Results : The inferior limiting sulcus of insula, limen insulae, medial sylvian groove, and caudate nucleus/amygdala were more appropriate anatomical structures than the roof/dorso-lateral wall of the temporal horn and lateral geniculate body which were used to describe previously for delineating the temporal stem. The particular space located inside the line connecting the inferior limiting sulcus of insula, limen insulae, medial sylvian groove/amygdala, and tail of caudate nucleus could be documented. This space included the extreme capsule, uncinate fasciculus, inferior occipito-frontal fasciculus, anterior commissure, ansa peduncularis, and inferior thalamic peduncle including optic radiations, whereas the stria terminalis, cingulum, fimbria, and inferior longitudinal fiber of the temporal lobe were not passing through this space. Also, this continued posteriorly along the caudate nucleus and limiting sulcus of the insula. Conclusion : The temporal stem is white matter fibers passing through a particular space of the temporal lobe located inside the line connecting the inferior limiting sulcus of insula, limen insulae, medial sylvian groove/amygdala, and tail of caudate nucleus. The three dimensional configurations of the temporal stem are expected to give the very useful anatomical and surgical insights in the temporal lobe.