A 77-year-old man presented with a metastatic brain tumor 15 years after nephrectomy for a renal cell carcinoma. Neurological examination showed recent memory disturbance and slight right hemiparesis. Magnetic resonance imaging revealed a round well-demarcated mass extending from the left thalamus to the left trigone of the lateral ventricle. Preoperative angiography showed tumor staining. Surgery was performed by opening the . Only biopsy could be performed because of extensive bleeding from the tumor. Histological examination identified metastatic renal cell carcinoma. Gamma knife surgery was performed which resulted in resolution of his hemiparesis. Metastatic renal cell carcinoma should be considered even if nephrectomy was performed 10 or more years before presentation.

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Temporomandibular disorders are a group of chronic and painful conditions in the masticatory musculature and temporomandibular joint. The pathological mechanisms underlying temporomandibular disorders remain to be clarified; however, it is known that disturbances in neurophysiological, cognitive, behavioral and neuromuscular functions are involved in the development and persistence of such disorders. In addition, it has been suggested that neuropathological changes in the central nervous system are involved in the development of temporomandibular disorders. This review describes changes in the cortical machinery in patients with temporomandibular disorders by comparing neuromagnetic signals between healthy subjects and patients elicited by observing jaw opening movements made by another person.

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Neural correlates of motion aftereffect (MAE) was investigated using magnetoencephalogram (MEG). MAE is an after effect caused by prolonged viewing of visual motion. After gazing at a moving pattern for a while, a stationary image will appear to move in the opposite direction. Evoked magnetic field was measured when a subject observing MAE in which concentric circles appear to continuously contracting after viewing expanding real motion. Visual evoked magnetic fields (VEFs) were averaged from 37 cortical points over occipital, temporal and parietal areas of the human brain during observing MAE. MRI (magnetic resonance imaging) brain images and estimated equal current dipole locus was fitted for each subject. The results clearly indicated the main brain location activated by MAE appears to be conjunction region (meeting area of lateral occipitotemporal sulcus and ) over the parieto-occipitotemporal cortex, corresponding to the human homologue of area MT.

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Endoscope biopsy guided navigation for intra-parenchymal lesions is safe and effective, but determination of the entry point and trajectory of the endoscopic biopsy is less clear. We describe preoperative planning based on stereotactic methods, and achieving the plan using several techniques. The preoperative planning was based on stereotactic methods such as determining target, entry point, and trajectory. A transparent sheath was advanced under guidance of the navigation system and specimens collected under visual endoscopic monitoring. After collecting specimens, intraoperative magnetic resonance imaging was performed for confirming accurate sampling. Correct specimens were obtained in 6 cases as confirmed by intraoperative magnetic resonance imaging. The histological diagnoses were diffuse large B-cell type malignant lymphoma (n = 3), astrocytoma (n = 1), glioblastoma (n = 1), and inflammatory changes without neoplastic cells (n = 1). No postoperative intracranial hemorrhage or other operative complications occurred. Preoperative planning based on stereotactic methods and procedures guided by navigation systems can achieve endoscopic biopsy for intraparenchymal lesions safely and accurately.

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The amygdala and uncus are located close to important neurovascular structures. We describe a safe technique for resection of amygdala and uncus. Under general anesthesia, the patient is positioned supine, with the head rotated approximately 20 degrees to the unoperated side and slightly extended. By using a trans-anterior T₁ subpial approach, the inferior horn of the lateral ventricle is opened, and hippocampectomy is performed. We treat an imaginary plane formed by the inferior circular sulcus of the insula, the endorhinal sulcus, and the inferior choroidal point as the upper border of amygdalar resection. After confirming the position of the inferior choroidal point, the border between the temporal stem and uncus is exposed from anterior to posterior. This border is continuous with the endorhinal sulcus. By exposing the endorhinal sulcus, the anterior choroidal artery and optic tract can be visualized. The amygdala is disconnected through complete exposure of the endorhinal sulcus to the inferior choroidal point. After the lateral side of the uncus is disconnected, the amygdala and uncus are removed en bloc. Since April 2014, we have used the described procedure to remove amygdalar–uncal lesions in 15 patients. The lesion was completely removed in all cases without complications. Histological specimens were obtained in all cases. Our procedure enables safe and complete removal of amygdalar–uncal lesions. Imagining the plane formed by the inferior circular sulcus, inferior choroidal point, and endorhinal sulcus is essential for complete removal of the lesion and for preserving important structures.

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Texture is one of the key perceptions that enable to comprehend the nature of multimodal signals from the environment according to their type and condition and convert them into a logical output in the central nervous system. Neuroimaging and some clinical studies have proven the importance of the ventral visual pathway in visual texture recognition. Although Alzheimer’s disease and dementia with Lewy bodies are believed to cause visual impairments, texture visualization has not been sufficiently investigated. In this paper, the author provides an overview of human visual texture sensation and focuses on texture recognition disorders in patients with cerebrovascular disease and dementia.

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Purpose: To determine the utility of stereoelectroencephalography (SEEG) in detecting the spatiotemporal dynamics of auditory naming-related high-gamma modulation.

Methods: This cross-sectional study investigated eight patients with drug-resistant focal epilepsy who performed an auditory naming task with vocal responses during SEEG recording. We generated time-frequency plots and animation videos delineating the dynamics of auditory naming-related high-gamma activity at 60-140 Hz.

Results: Auditory naming elicited high-gamma augmentation in the bilateral superior temporal gyri, insula, left triangular part of the inferior frontal gyrus, precentral gyrus, and right lateral occipital complex between 160 and 210 ms after stimulus onset, followed by the right cuneus after 1080 ms. Augmentation in the bilateral superior temporal gyri continued during stimulus presentation. Around the stimulus offset, the left precentral gyrus showed reaugmentation, followed by the right lingual gyrus and bilateral superior temporal gyri. Frontotemporal activation was consistent with the results of previous electrocorticography (ECoG) studies. These studies did not detect any activity in the insula associated with auditory naming.

Conclusion: This study demonstrated the utility of SEEG for analyzing high-gamma modulations by replicating the spatiotemporal dynamics determined in previous ECoG studies. Compared to ECoG, SEEG may be beneficial for detecting high-gamma modulations in deep brain structures such as the insula.

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神経美学（neuroaesthetics）とは，様々な美学的体験（美的範疇）や芸術的活動に関係する脳機能と認知の仕組みを研究する認知神経科学の一分野である．誕生から20年弱の比較的新しい分野だが，美学的体験や芸術についての認知神経科学・心理学的アプローチは各国の研究機関でも重視されている．現在，欧州と北米を中心にロンドン大学ユニバーシティ校，ウィーン大学，マックスプランク研究所，ニューヨーク大学，ペンシルベニア大学，UCバークレーなど主要大学・研究機関において研究講座が開設されている．ロンドン大学ゴールドスミスカレッジ心理学部では，正式に当分野を修めることのできる修士課程コースも開講され，今後さらなる展開が期待される．

知覚・認知と美学的体験との関係を科学の対象として研究した最初の試みは，19世紀末頃のグスタフ・フェヒナーによる実験美学に端を発する．複雑な感性的体験を一つの変数で説明し，共通の要素を見つけることで，多様な感性的体験を定式化しようと試みたのだ．しかしフェヒナーにとってより重要な目的は，刺激への反応の背後に想定される神経活動との関係性を説明することであり，それは心理物理学と実験美学のひとつの目標でもあった．非侵襲の脳機能画像法と認知神経科学の発展により，現在その実証性の理念は神経美学に引き継がれたといえる．本稿では，前半で神経美学，特に視覚における神経美学研究を概観する．続いて後半では，現在注目されている負の感情価を伴う美的感性について仮説を含めて議論する．心理学的・脳機能的な観点から，負の感情価の伴う美的体験について仮説と今後の検討課題を提示することを目的としている．なお本稿では，主に視覚・視覚芸術に関する神経美学を扱う．音楽に関する認知神経科学的検討は，本特集号の大黒による論考を参照されたい．

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