• Title/Summary/Keyword: cortical activation

Search Result 122, Processing Time 0.029 seconds

Acupuncture Analgesia : A Sensory Stimulus Induced Analgesia Observed by functional Magnetic Resonance Imaging (침의 진통효과: 체성감각신경자극으로 유도된 진통작용에 대한 기능성자기공명영상장치를 이용한 연구)

  • Cho, Zang-hee;Hwang, Seon-chool;Son, Young-don;Kang, Chang-ki;Wong, Edward K.;Bai, Sun-joon;Lee, Un-jung;Sung, Kang-kyung;Park, Tae-seok;Kim, Young-bo;Min, Hoon-ki;Oleson, Terry
    • Journal of Acupuncture Research
    • /
    • v.21 no.2
    • /
    • pp.57-71
    • /
    • 2004
  • Objective : Physiological evidence regarding acupuncture's effect in human patients is not yet well established, despite considerable evidence for its therapeutic efficacy. Besides target or disease specificity of acupuncture, acupuncture analgesia (AA) appears to be another large subclass that poses many questions, such as whether there is point specificity with respect to which acupoint is most effective for a particular condition. Methods : We observed brain activation with functional magnetic resonance imaging (fMRI) using a set of stimuli that consist of pain, pain following Meridian acupuncture, and pain following Sham acupuncture. Results : Among the new observations, the most interesting fact is that data sets of both Meridian acupuncture and Sham acupuncture show decreased activation of the same brain areas related to the pain processing signals. Present functional MRI study demonstrate two important biological observations that could elucidate AA mechanism in human participants: the effects of acupuncture occur through mediation of the higher brain areas. Sham acupuncture stimulation appears to be almost as effective as traditional Meridian acupoint stimulation, suggesting that acupuncture is not entirely point specific. Decreased activation in the limbic paleo cortical areas appears to be the probable neurological manifestation of AA and strongly implies that acupuncture stimulation inhibits the transmission of ascending pain signals to the higher cortical areas by the previously known descending pain inhibitory circuit. Conclusion : We, therefore, a hypothesized that this pain inhibitory circuit is initiated and mediated via the broad sense Hypothalamus Pituitary Adrenal (BS HPA) axis in conjunction to the "sensory stimulation."

  • PDF

Disturbed Functional Asymmetry of Sensorimotor Cortex in Schizophrenia: A Study with Functional Magnetic Resonance Imaging (정신분열증에서 감각운동피질의 기능적 비대칭성의 장애: 기능적 자기공명영상을 이용한 연구)

  • Ahn, Kook-Jin;Chae, Jeong-Ho;Kim, Tae;Kim, Euy-Neyng;Lee, Jee-Mun;Choi, Kyu-Ho;Hahn, Seong-Tai
    • Investigative Magnetic Resonance Imaging
    • /
    • v.4 no.1
    • /
    • pp.52-57
    • /
    • 2000
  • Purpose : The purpose of this study was to investigate the pattern of cerebral response to motor tasks in patients with schizophrenia compared with normal subjects using functional MRI. Materials and methods ; Nine right handed-schizophrenic patients and six right-handed normal subjects were included. We used right hand movement as task. Series of 120 consecutive echo-planar images per section were acquired during three cycles of task and rest activations. Lateralization index of cortical response was measured and compared between patients and normal subjects. Results ; Right hand motor task was associated with greater activation in left sensorimotor cortex than the right in normal subjects. Schizophrenia patients showed relatively decreased activation in left cortex and increased activation in right cortex compared with normal subjects. In one patient, reversed lateralization was noted. Conclusion : Normal hemispheric asymmetry of cortical response to motor task was found in different pattern in schizophrenia. Our result is consistent with functional disturbance of motor circuitry in this disorder. Functional MRI will play an important role in diagnosis and research of this disorder.

  • PDF

A Review of the Plasticity and Constraint Induced Movement Therapy : Children With Spastic Hemiplegic Cerebral Palsy (신경가소성 원리를 이용한 강제유도운동치료에 대한 고찰: 경직성 편마비형 뇌성마비 아동을 대상으로)

  • Cho, Sang-Yoon
    • Therapeutic Science for Rehabilitation
    • /
    • v.2 no.1
    • /
    • pp.13-23
    • /
    • 2013
  • Constraint-Induced Movement Therapy(CIMT) is considered as one of the most interesting upper extremity rehabilitation in the field of neurorehabilitation. CIMT is an intensive training provided in the affected upper limb for 6 hours a day, 5 days a week for 2 weeks, while unaffected arm is restrained for 90% of waking hours. Recently, instead of CIMT, modified Constraint-Induced Movement Therapy(mCIMT) has been applied because of the clinical limitations of CIMT. CIMT or mCIMT studies have used various outcome instruments to measure different aspects of upper limb function after intervention. There are various kinds of evaluation tools to measure different aspects of upper limb function after CIMT intervention. It has been proven that Pediatric Motor Activity Log(PMAL), Quality of Upper Extremities Skills Test(QUEST), Melbourne Assessment of Unilateral Upper Limb Function(MAULF), Assisting Hand Assessment (AHA) are effective. The purpose of this study was to investigate the cortical change in children with hemiplegic cerebral palsy after CIMT. As a result, use-dependent cortical reorganization was revealed. Also, increased activity of the contralateral motor cortex and decreased activity of the ipsilateral cortex were found. It supports the mechanism of cortical reorganization, the principles of neural plasticity and specifically activation of the contralateral cortex, for improving upper limb function after CIMT.

Laser Speckle Contrast Imaging for Measuring Cerebral Blood Flow Changes Caused by Electrical Sensory Stimulation

  • Cho, Ahra;Yeon, Chanmi;Kim, Donghyeon;Chung, Euiheon
    • Journal of the Optical Society of Korea
    • /
    • v.20 no.1
    • /
    • pp.88-93
    • /
    • 2016
  • Recently laser speckle contrast (LSC) imaging has become a widely used optical method for in vivo assessment of blood flow in the animal brain. LSC imaging is useful for monitoring brain hemodynamics with relatively high spatio-temporal resolution. A speckle contrast imaging system has been implemented with electrical sensory stimulation apparatus. LSC imaging is combined with optical intrinsic signal imaging in order to measure changes in cerebral blood flow as well as neural activity in response to electrical sensory stimulation applied to the hindlimb region of the mouse brain. We found that blood flow and oxygen consumption are correlated and both sides of hindlimb activation regions are symmetrically located. This apparatus could be used to monitor spatial or temporal responses of cerebral blood flow in animal disease models such as ischemic stroke or cortical spreading depression.

Physiological manifestations of the modulation of post-stress recovery process by emotion-inducing stimulation of auditory and visual modality (시각자극에 의해 유발된 스트레스 생리반응의 회복과정에 미치는 정서청각자극의 효과)

  • Estate Sokhadze
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
    • /
    • 1998.04a
    • /
    • pp.44-56
    • /
    • 1998
  • Effects of the music and white noise on recovery of the autonomic and cortical responses evoked by aversive visual stimulation were analyzed in 20 subjects. It was suggested that the music is able to exert modulatory influence on the physiological activity resulted from exposure to unpleasant IAPS based stimuli. Spectral power of DDG, heart rate(HR)respiration rate (RSR) and electrodermal activity(EDA)were recorded and analyzed for each experimental condition. It was observed HR and RSR deceleration, increased EDA and electrocortical activation expressed in decreased alpha power and increase of delta activity ao occipital and frontal areas. Obtained results suggest that audutory stimulation both with pleasant and sad music lead to restoration of pre-stimulation activation levels of most physiological parameters during listenning to music and in post-stimulation period. White noise evoked short-term physiological responses typical for orienting reaction and quite distinct from changes produced by music. Available data to differentiate effeces among pleasant and sad music, due toqualitative similarities of physilolgical patterns, but suppert an assumption that music is capable to facilitate the process of recovery of physilolgical responses elicited by visual stimulation of negative valence, thus positively modulate post-stress state.

  • PDF

Functional MR Imaging of Cerebral Motor Cortex on 3 Tesla MR Imaging : Comparison between Gradient and Spin-Echo EPI Techniques (3T에서 뇌 운동피질의 기능적 자기공명영상 연구 : Gradient-Echo와 Spin-Echo EPI의 비교)

  • Goo, Eeu-Hoe;Chang, Hye-Won;Chung, Hwan
    • Korean Journal of Digital Imaging in Medicine
    • /
    • v.9 no.2
    • /
    • pp.31-38
    • /
    • 2007
  • To evaluate the accuracy and extent in the localization of cerebral motor coutex activation using a gradient- echo echo planar imaging(GE-EPI) compared to spin-echo echo planar iimaging(SE-EPI) on 3T MR imaging. Functional MR imaging of cerebral motor cortex activation was examined in GE-EPI and SE-EPI in five healthy male volunteers. A right finger movement was accomplished with a paradigm of 6 task and rest, periods and the cross-correlation was used for a statistical mapping algorithm. We evaluated any sorts of differenced of the time seried and the signal intensity changes between the rest and task periods obtained with two technoques. The qualitative analysis was distributed with activation sites of large veins and small veins by using two techniques and was found that both the techniques were clinically uesful for delineating large veins and small veins in fMRL Signal intensity charge of the rest and activation periods provided simmilar activations in both methods(GE-EPI : 0.93$\pm$0.11, SE-EPI : 0.80$\pm$.015) but the signal intensity in GE-EPI(133.95$\pm$15.76) was larger than in SE-EPI(74.5$\pm$18.90). The average SNRs of EPI raw data were higher at SMA in SE-EPI(48.54$\pm$12.37) than GE-EPI(41.4$\pm$12.54) and at M1 in SE-EPI(43.24$\pm$11.77) than GE-EPI(38.27$\pm$6.53). The localization of activation voxels of the GE-EPI showed a larger vein but the SE-EPI generally showed small vein. Then the analysis results of the two techniques were used for a statistacal paired student t-test. SE-EPI was found clinically useful for localizing the cerebral moter cortex cativation on 3.0T, but showed a little different activation patterns comparad to GE-EPI. In conclusion, SE-EPI may be feasible and can detect true cortical activation from capillaries and GE-EPI can obtain the large veins in the motor cortex activation on 3T MR imaging.

  • PDF

PHYSIOLOGICAL INDICATORS OF EMOTION AND ATTENTION PROCESSES DURING AFFECTIVE AND ORIENTING AUDITORY STIULATION (청각자극에 의해 유발된 정서 및 주의반응의 생리적 지표)

  • Estate M. Sokhadze
    • Proceedings of the Acoustical Society of Korea Conference
    • /
    • 1998.06c
    • /
    • pp.291-296
    • /
    • 1998
  • In the experiment carried out on 20 college students, recorded were frontal, temporal and occipital EEG, skin conductance response, skin conductance level, heart rate and respiration rate during listening to two music fragments with different affective valences and white noise administered immediately after negative visual stimulation. Analysis of physiological patterns observed during the experiment suggests that affective auditory stimulation with music is able to selectively modulate autonomic and cortical activity evoked by preceding aversive visual stimulation and to restore initial baseline levels. On other hand, physiological responses to white noise, which does not possess emotion-eliciting capabilities, evokes response typical for orienting reaction after the onset of a stimulus and is rapidly followed by habituation. Observed responses to white noise were similar to those specific to attention only and had no evidence for any emotion-related processes. Interpretation of the obtained data is considered in terms of the role of emotional and orienting significance of stimuli, dependence of effects on the background physiological activation level and time courses of attention and emotion processes. Physiological parameters are summarized with regard to their potential utility in differentiation of psychological processes induced by auditory stimuli.

  • PDF

Neuroprotection of Lithium is Associated with Inhibition of Bax Expression and Caspase 8 Activation

  • Kwon, Gee-Youn;Kim, Soo-Kyung
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.5 no.5
    • /
    • pp.389-396
    • /
    • 2001
  • Neuroprotective properties of lithium were investigated by using in vivo NMDA excitotoxicity model. The appearance of TUNEL positive cells was prominent within 24 h of NMDA (70 mg/kg, i.p.) injection in the regions of the cortex, hippocampal formation, and thalamus of mouse cerebrum. NMDA treatment resulted in the extensive enhancement of Bax immunoreactivity in the cortical and hippocampal regions. NMDA also increased the immunoreactivity of caspase 8 in the similar regions of the mouse cerebrum. However, the increased immunoreactivity of Bax and caspase 8 were dramatically attenuated by chronic lithium pretreatment (lithium chloride, 300 mg/kg/d, i.p. for $7{\sim}10$ days). At the same time, lithium ion blocked the appearance of TUNEL positive cells, and the morphological assessment indicated an effective neuroprotection by lithium against NMDA excitotoxicity. Although the exact action mechanism of lithium is not straightforward at this time, we propose that the inhibition of Bax and caspase cascade is involved in the neuroprotective action of lithium.

  • PDF

Neuroactivation studies using Functional Brain MRI (기능적 자기공명영상을 이용한 뇌활성화 연구)

  • Chung, Kyung-Ho
    • The Korean Journal of Nuclear Medicine
    • /
    • v.37 no.1
    • /
    • pp.63-72
    • /
    • 2003
  • Functional MRI (fMRI) provides an indirect mapping of cerebral activity, based on the detection of the local blood flow and oxygenation changes following neuronal activity (Blood Oxygenation Level Dependent). fMRI allows us to study noninvasively the normal and pathological aspects of functional cortical organization. Each fMRI study compares two different states of activity. Echo-Planar Imaging is the technique that makes it possible to study the whole brain at a rapid pace. Activation maps are calculated from a statistical analysis of the local signal changes. fMRI is now becoming an essential tool in the neurofunctional evaluation of normal volunteers and many neurological patients as well as the reference method to image normal or pathologic functional brain organization.

Erythropoietin increases neuronal cell differentiation : association of transcriptional factors AP-l and NF-$\kappa$B activation

  • Lee, Sang-Min;Park, Hye-Ji;Lee, Yoot-Mo;Moon, Dong-Cheul;Kim, Kyong-Soon;Cho, Kyong-Ju;Yoon, Do-Young;Song, Suk-Gil;Hong, Jin-Tae
    • Proceedings of the PSK Conference
    • /
    • 2003.10b
    • /
    • pp.169.2-170
    • /
    • 2003
  • Erythropietin (EPO), a hematopoietic factor is also required for normal brain development, and its receptor is localized in brain. Therefore, it is possible that EPO could act as a neurotropic factor inducing differentiation of neurons. The present study, we therefore investigated whether EPO can increase differentiation of undifferentiated cortical neuron isolated from postneonatal (Day 1) rat brains and PC12 cell, undifferentiated dopaminagic cell line. EPO dose (1-100 U/ml) dependently increased cell differentiation and expression of differentiation marker gene (neurofilament and tyrosine hydroxylase) in both cells. (omitted)

  • PDF