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全文: "Visual cortex"
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  • Tadaharu TSUMOTO
    The Japanese Journal of Physiology
    1990年 40 巻 5 号 573-593
    発行日: 1990年
    公開日: 2004/06/18
    ジャーナル フリー
  • Tadahisa KURIMOTO, Kentaro KOSHINO, Kuniyuki SOMEDA, Satoru KUBOTA, Takayuki NAKAJIMA, Naoki KAGEYAMA
    Neurologia medico-chirurgica
    1971年 11 巻 104-105
    発行日: 1971年
    公開日: 2007/08/17
    ジャーナル フリー
  • 堀田 利夫, 竹中 敏文
    The Japanese Journal of Physiology
    1962年 12 巻 3 号 262-271
    発行日: 1962年
    公開日: 2011/06/07
    ジャーナル フリー
    Interaction between responses elicited in the somatosensory cerebral cortex, following single shock stimulation of the visual cerebral area and the superficial radial nerve or the contralateral somatosensory area, was studied in cats anesthetized with chloralose and immobilized with Faxedil. The range of latencies of discharges for the initial spikes from stimulation of the primary visual cortex varied from 8 to 30msec in the somatosensory cortex. Spike discharges, recorded from a single cortical neuron, were reciprocally interacted by a conditioning-testing procedure and were blocked by a preceding response in some neurons; in other neurons, temporal summation was shown.The depressive effect following the first stimulus was found often to last more than 100 msec. Blocking of spike discharges following stimulation of the visual cortex was produced by the hyperpolarized afterpotential in the response elicited from stimulation of the sensory nerve. These results suggest that associative volleys from another cortical area modify activity of the somatosensory cortical neuron as depression or temporal summation.
  • Gil-Hyun Kim, Hang-Gu Kim, Chang-Jin Jeon
    ACTA HISTOCHEMICA ET CYTOCHEMICA
    2018年 51 巻 5 号 153-165
    発行日: 2018/10/31
    公開日: 2018/10/31
    [早期公開] 公開日: 2018/09/29
    ジャーナル フリー HTML

    The purpose of the present study was to investigate the organization of choline acetyltransferase (ChAT)-immunoreactive (IR) fibers in the visual cortex of the microbat, using standard immunocytochemistry and confocal microscopy. ChAT-IR fibers were distributed throughout all layers of the visual cortex, with the highest density in layer III and the lowest density in layer I. However, no ChAT-IR cells were found in the microbat visual cortex. ChAT-IR fibers were classified into two types: small and large varicose fibers. Previously identified sources of cholinergic fibers in the mammalian visual cortex, the nucleus of the diagonal band, the substantia innominata, and the nucleus basalis magnocellularis, all contained strongly labeled ChAT-IR cells in the microbat. The average diameter of ChAT-IR cells in the nucleus of the diagonal band, the substantia innominata, and the nucleus basalis magnocellularis was 16.12 μm, 13.37 μm, and 13.90 μm, respectively. Our double-labeling study with ChAT and gamma-aminobutyric acid (GABA), and triple labeling with ChAT, GABA, and post synaptic density 95 (PSD-95), suggest that some ChAT-IR fibers make contact with GABAergic cells in the microbat visual cortex. Our results should provide a better understanding of the nocturnal bat visual system.

  • HIROSHI KATO, SEISHO ITO, TETSURO OGAWA
    The Tohoku Journal of Experimental Medicine
    1979年 128 巻 2 号 197-198
    発行日: 1979年
    公開日: 2008/11/28
    ジャーナル フリー
    To reveal the recurrent inhibitory circuit in the visual cortex, a depolarizing current was applied through a glass microelectrode to an impaled cell in an in vitro slice of the visual cortex obtained from a cat anesthetized with pentobarbital. The cell reported here produced inhibitory postsynaptic potentials (IPSPs) following single spikes or bursts of spikes which were elicited by intracellularly applied current. This observation indicates that IPSPs have been mediated by the recurrent inhibitory circuit via axon collaterals of the impaled cell.
  • Ichiro Kuriki
    生体医工学
    2017年 55Annual 巻 4PM-Abstract 号 373
    発行日: 2017年
    公開日: 2017/09/13
    ジャーナル フリー

    Color is one of the fundamental information in human vision. However, cortical representation of color information is not well understood. It is known that differences of cone responses represent color information at the lower levels of visual system and the higher order visual tasks, e.g., color memory, use categorical representation. We investigated the color representation in human visual cortex by measuring brain activities in adults and in infants. The fMRI study using differential phase encoding technique and adaptation experiments revealed that neural systems that selectively respond to intermediate colors are present at the level of primary visual cortex. The NIRS study in prelingual infants was conducted by investigating cortical response changes while presenting color pairs that span across a border of color category or that stays within a category. The result revealed that the categorical color representation is already. Implications from these studies will be discussed in the talk.

  • Ya-Nan Gu, Hang-Gu Kim, Chang-Jin Jeon
    ACTA HISTOCHEMICA ET CYTOCHEMICA
    2015年 48 巻 4 号 125-133
    発行日: 2015/08/27
    公開日: 2015/08/27
    [早期公開] 公開日: 2015/08/20
    ジャーナル フリー HTML
    Microchiroptera (microbats) is a suborder of bats thought to have degenerated vision. However, many recent studies have shown that they have visual ability. In this study, we labeled neuronal nitric oxide synthase (nNOS)—the synthesizing enzyme of the gaseous non-synaptic neurotransmitter nitric oxide—and co-localized it with calbindin D28K (CB), calretinin (CR), and parvalbumin (PV) in the visual cortex of the greater horseshoe bat (Rhinolophus ferrumequinum, a species of microbats). nNOS-immunoreactive (IR) neurons were found in all layers of the visual cortex. Intensely labeled neurons were most common in layer IV, and weakly labeled neurons were most common in layer VI. Majority of the nNOS-IR neurons were round- or oval-type neurons; no pyramidal-type neurons were found. None of these neurons co-localized with CB, CR, or PV. However, the synthesis of nitric oxide in the bat visual cortex by nNOS does not depend on CB, CR, or PV.
  • Yukinobu IKEDA, Makoto SAKAI, Fumio YAGI
    生理心理学と精神生理学
    2000年 18 巻 1 号 35-43
    発行日: 2000/04/30
    公開日: 2012/11/27
    ジャーナル フリー
    In a previous study we investigated the effects of callosal transected lesions made 10 weeks earlier (the 10-week-old callosal transected lesions), either at 3 weeks of age or at 13 weeks of age, upon the acquisition of a black-white (BW) discrimination in rats either with one eye removed at birth (OEB) or at 13 weeks of age (OET) following lesions of the contralateral (CT) visual cortex to the remaining eye. The CT visual cortex lesions were performed right before the training of BW discrimination. We found that the 10-week-old callosal transected lesions facilitated the acquisition in OEBs when the callosal lesions were given at 3 weeks of age, and to a lesser extent at 13 weeks of age. We also found that the same type of callosal transected lesions did not do so in OETs, regardless of the age when the callosal lesions were made.
    Since the CT visual cortex lesions inevitably result in damage of the callosal neurons, and lead to de-generation of the callosal afferents in the ipsilateral (IP) visual cortex, the present study was undertaken to investigate if the CT visual cortex lesions made 10 weeks earlier (the 10-week-old CT visual cortex lesions), made either at 3 weeks of age or 13 weeks of age, would affect the acquisition of BW discrimination in OEBs and OETs, like the 10-week-old callosal transected lesions employed in the previous study mentioned above.
    We found that in both OEBs and OETs the overall pattern of the facilitation effects of the 10-week-old CT visual cortex lesions on the acquisition of BW discrimination is, in general, the same as that observed in the 10-week-old callosal transected lesions, but the facilitative effect of the 10-week-old CT visual cortex lesions is more prevailing and pronounced. The findings are discussed in relation to the possible involvement of neurotrophic factors, released when the CT visual cortex lesions were made, in synaptic reorganization, and also in relation to the possibility of the increased use of the uncrossed visual pathways.
  • Eun-Ah Ye, Tae-Jin Kim, Jae-Sik Choi, Mi-Joo Jin, Young-Ki Jeon, Moon-Sook Kim, Chang-Jin Jeon
    ACTA HISTOCHEMICA ET CYTOCHEMICA
    2006年 39 巻 2 号 47-54
    発行日: 2006年
    公開日: 2006/04/22
    [早期公開] 公開日: 2006/03/17
    ジャーナル フリー
    The subunit composition of the AMPA receptor is critical to its function. AMPA receptors that display very low calcium permeability include the GluR2 subunit, while AMPA receptors that contain other subunits, such as GluR1, display high calcium permeability. We have studied the distribution and morphology of neurons containing GluR1 in the hamster visual cortex with antibody immunocytochemistry. We compared this labeling to that for calbindin D28K, parvalbumin, and GABA. Anti-GluR1-immunoreactive (IR) neurons were located in all layers. The highest density of GluR1-IR neurons was found in layers II/III. The labeled neurons were non-pyramidal neurons, but were varied in morphology. The majority of the labeled neurons were round or oval cells. However, stellate, vertical fusiform, pyriform, and horizontal neurons were also labeled with the anti-GluR1 antibody. Two-color immunofluorescence revealed that many of the GluR1-IR neurons in the hamster visual cortex were double-labeled with either calbindin D28K (31.50%), or parvalbumin (22.91%), or GABA (63.89%). These results indicate that neurons in the hamster visual cortex express GluR1 differently according to different layers and selective cell types, and that many of the GluR1-IR neurons are limited to neurons that express calbindin D28K, parvalbumin, or GABA. The present study elucidates the neurochemical structure of GluR1, a useful clue in understanding the differential vulnerability of GluR1-containing neurons with regard to calcium-dependent excitotoxic mechanisms.
  • The Keio Journal of Medicine
    2002年 51 巻 supplement1 号 42-44
    発行日: 2002年
    公開日: 2009/03/27
    ジャーナル フリー
  • Kaoru INOUE, Toshio TERASHIMA, Yoshiro INOUE
    Okajimas Folia Anatomica Japonica
    1992年 68 巻 6 号 319-331
    発行日: 1992年
    公開日: 2012/09/24
    ジャーナル フリー
    The postnatal development of the corticotectal projection was investigated by injecting the axon tracer DiI into the visual cortex of mouse pups. It was found that DiI-labeled axons arrive at the ipsilateral superior colliculus and enter the optic nerve layer of this structure on postnatal days 3 and 4 (P3-P4). These corticotectal axons extend into the caudal end of the superior colliculus on P4 and give off small collateral branches that ascend vertically to the superficial gray layer. During the first two postnatal weeks, the collateral branches do not form a demarcated terminal zone, but rather diffusely spread within the superficial gray layer of the superior colliculus. These collateral branches continue to dichotomize and form a bright terminal zone within the superficial gray layer on P11. The terminal zone decreases in size during the second and third postnatal weeks, and appears to be of the same size when compared with the adult counterpart by P19. The terminal zone of the corticotectal axons from the visual cortex is established by P19. In parallel with the maturation of the terminal zone of the corticotectal projection, the distal segment of the corticotectal axons is lost during the second postnatal week. We conclude that the growing tips of the corticotectal axons do not strictly project to their future terminal zone within the superior colliculus, and 'misdirected' axons are eliminated during the early postnatal period.
  • Nigel W. Daw, Christopher J. Beaver
    The Keio Journal of Medicine
    2001年 50 巻 3 号 192-197
    発行日: 2001年
    公開日: 2009/06/16
    ジャーナル フリー
    There is a shift in ocular dominance of cells recorded in the visual cortex which occurs after closure of one eye during a critical period lasting from eye opening to puberty. Three criteria distin-guish factors that are crucially related to ocular dominance plasticity: 1) the factor should be more concentrated or active at the peak of the critical period; 2) dark rearing, which makes the cortex less plastic early in the critical period and more plastic late in the critical period, should have a similar effect on the factor, and 3) antagonists or inhibitors of the factor should block ocular dominance plasticity. The second criterion can be used to distinguish activity-related factors that may simply increase or de-crease with development from factors that are more specifically related to plasticity. Two factors cur-rently fulfill these criteria, namely N-methyl-D-asparate (NMDA) receptors and protein kinase A (PKA). PKA and NMDA receptors are linked through calcium, since calcium influx through the NMDA receptor increases the production of cyclic AMP by calcium-sensitive adenylate cyclase, which in turn activates PKA. PKA is specifically involved, since protein kinase G and protein kinase C antagonists do not inhibit ocular dominance plasticity. However, NMDA agonists and PKA activators by themselves are not known to bring back plasticity. Thus there may be two or more pathways for ocular dominance plasticity acting in parallel with each other: for example, metabotropic glutamate receptors may act in parallel with NMDA receptors to change calcium levels within the cell.
  • Kaoru INOUE, Toshio TERASHIMA, Yoshiro INOUE
    Okajimas Folia Anatomica Japonica
    1991年 67 巻 6 号 479-492
    発行日: 1991/03/20
    公開日: 2012/09/24
    ジャーナル フリー
    We studied the postnatal development of the corticopontine tract in mice by the injection of the axon tracer DiI into the visual cortex. In the postnatal day (P) 0.5 mouse, labeled pyramidal tract fibers pass through the internal capsule and cerebral peduncle, grow over the basilar pontine gray, and enter into the medullary pyramid (in this study, P0 refers to the first 24 hours after birth). Small collateral branches arise from these pyramidal tract fibers on P0.5-1.0, and elongate quickly into the basilar pontine gray around P2-4. These collateral branches give off many secondary branches on P4 and form the bright terminal zone in the rostral portion of the lateral basilar pontine gray on P9. In the P16 mouse, this terminal zone is more restricted, suggesting, on the basis of the anterograde DiI labeling technique, that the visual corticopontine projection matures by P16. DiI-labeled pyramidal tract fibers distal to the branching point of the pontine collaterals are found during the postnatal two weeks, but disappear by the later stages. We conclude that the visual corticopontine tract develops as collateral branches of the transient pyramidal tract fibers arising from the visual cortex of the mouse, as just described in the rat (O'Leary and Terashima, Neuron 1: 901-910,1988).
  • MAKOTO TAMAI, TETSURO OGAWA
    The Tohoku Journal of Experimental Medicine
    1972年 107 巻 2 号 127-142
    発行日: 1972年
    公開日: 2008/11/28
    ジャーナル フリー
    In chloralose-anesthetized cats, electrical stimulation of the optic tract evoked a negative-positive field potential wave at the surface of the ipsilateral superior colliculus which reversed to a positive-negative wave at the deeper part of the superficial gray layer. The maximal amplitude of the deep positivity was reached at the optic layer. Cortical stimulation of visual and surrounding areas elicited similar field potentials in the ipsilateral superior colliculus. Reversal in polarity occurred at the same depth as did for the tract-evoked field potential. In general, stimulation of cortical areas surrounding the visual cortex, for example, the posterior suprasylvian gyrus, gave rise to a larger response than stimulation of the visual cortex. Reversible inactivation of the cortical visual and adjacent areas by cooling resulted in a reduction of the tract-evoked field potential with a gradual recovery to the initial amplitude after removal of the cooling agent. This finding indicates that the geniculocortico-tectal pathway contributes the generation of collicular response to stimulation of the retinotectal pathway. Topographical interrelationships between the effective cortical area and the superior colliculus were examined with the amplitude of cortically evoked collicular responses as an index. It was revealed that the junctional part between the lateral and postlateral gyri was related to the posterior part of the superior colliculus and that the upper part of the postsuprasylvian gyrus was associated with the anterior part of the superior colliculus. As to interaction between cortico-tectal and retino-tectal inputs, it was found that preceding stimulation of the effective cortical areas produced an initial facilitation from 50 to 200 msec followed by a depression of collicular response to optic tract stimulation lasting for as long as 500 msee.
  • 番 浩志, ドリタ チャン, アンドリュー ウェルチマン
    映像情報メディア学会誌
    2015年 69 巻 7 号 510-515
    発行日: 2015年
    公開日: 2017/07/03
    ジャーナル フリー
  • 鈴木 寿夫, 加藤 栄一
    The Tohoku Journal of Experimental Medicine
    1965年 86 巻 3 号 277-289
    発行日: 1965/08/25
    公開日: 2008/11/28
    ジャーナル フリー
  • The Keio Journal of Medicine
    2002年 51 巻 supplement1 号 36-38
    発行日: 2002年
    公開日: 2009/03/27
    ジャーナル フリー
  • 時々輪 浩穏
    The Japanese Journal of Physiology
    1973年 23 巻 5 号 465-476
    発行日: 1973年
    公開日: 2011/06/07
    ジャーナル フリー
    In order to reexamine the cortical distribution of the callosal connection, as well as its topographical relation to the binocular area in the rabbit visual cortex, the distribution of cortical responses evoked by electrical stimulation of the optic nerve and by direct cortical stimulation of the opposite visual area were studied in thirty immobilized animals.
    1. The early response to ipsilateral optic nerve stimulation was similar in latency and waveform to that of the contralateral stimulation, and the area giving this response was determined as the binocular area. The binocular area which was a band of 6-7mm wide extended from the anteromedial to the posterolateral portion across the visual cortex.
    2. Besides the early response, the binocular area showed the later response to ipsilateral optic nerve stimulation. The later response was found to be mediated via the corpus callosum, because it was abolished by cooling the opposited visual cortex. The interval between the beginning of the early and late responses was comparable with the latency of the transcallosal response elicited by direct cortical stimulation. The transcallosal response was also abolished permanently by cutting the posterior half of the corpus callosum. The area of transcallosal response and the area effective in eliciting this response were found to be in good agreement with each other and with the binocular area.
    3. The callosal connection between the two binocular areas was not necessarily homotopic. For diffusely distributed points of stimulation in the binocular area of one cortex the points showing the maximal callosal responses in the other cortex were arranged in a narrow band in the middle of the binocular area. This band, about 1mm wide and running obliquely about 45 degrees to the midline, seemed to correspond to the projection line of the vertical meridian (decussation line) determined by Thompson et al.
    These results suggest that the whole binocular area of both hemispheres in the rabbit are interconnected via the corpus callosum, and that the callosal fibers from the binocular area of one cortex terminate most densely in the middle of the opposite binocular area.
  • Jun-ya Okamura, Shunta Satonaka, Koudai Nagae, Ryousuke Hata, Gang Wang
    生体医工学
    2014年 52 巻 Supplement 号 O-373-O-374
    発行日: 2014年
    公開日: 2014/10/04
    ジャーナル フリー
    Extracellularly recorded neuronal activity contains spikes superimposed on local field potentials (LFPs). Spiking activities have been analyzed extensively, while the LFPs were filtered out. In the present study, to understand the correlated activities in separate cortical areas, multichannel recording electrodes were placed in the cat early visual cortex and the relationships of the activities were analyzed by comparing cross correlations (CC) of the spikes and phase locking values (PLV) of the LFPs. Both CC and PLV decreased as the difference in the preferred orientation increased. The peak values of the CC decreased as the separation of the activity pairs increased over 200μm. The PLV had two peaks in early and late phases of the responses. Both peaks decreased as the separation of the activity pairs increased over 400μm. The early and late phases of the PLV may contain different information in responses to the visual stimuli.
  • Hideyuki NAKAMA, Satoru OHTOMO, Taisuke OTSUKI, Yuu KANEKO, Takashi OHNISHI, Hiroshi MATSUDA
    Neurologia medico-chirurgica
    2002年 42 巻 8 号 356-360
    発行日: 2002年
    公開日: 2005/06/16
    ジャーナル オープンアクセス
    A 14-year-old boy suffered from daily epileptic seizures originating from the left polymicrogyric occipital cortex. Visual activation positron emission tomography (PET) was used to map the function of the occipital cortex presurgically. Loss of visual function in the left occipital cortex was suggested by both visual activation PET and electrical cortical stimulation. Left occipital lobectomy resulted in a completely seizure-free status without deterioration in the visual function. Preoperative evaluation of the visual function in the epileptogenic occipital cortex by activation studies using PET or functional magnetic resonance imaging is the key to the successful surgical treatment of occipital lobe epilepsy.
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