Parkinson's disease is characterized by impaired initiation of movement, muscular rigidity and tremor clinically. In traditional Korean medicine, acupoints LR3 (Taechung) and GB34 (Yangneungcheon) have been used to treat such movement related disorders. Recently, we showed the neuroprotective and movement promoting effects of these acupoints with 6-OHDA induced Parkinson's disease rat model. In this study, we observed acupuncturing on (1) LR3 and (2) GB34 respectively, or on (3) both acupoints together activate movement-related brain areas with functional MRI (fMRI). Ten right-handed subjects participated in these fMRI experiments using a blocked paradigm on a 3T MRI scanner. In the group of LR3, medial frontal gyrus (Left ;L), fusiform gyrus (L), cerebellum (L), pons (L) and thalamus (Right ;R) were activated. In the group of GB34, middle frontal gyrus (R), lingual gyrus (L), cerebellum (R), parahippocampal gyrus (L), insula (L), cingulate gyrus (R, BA24), posterior cingulate gyrus (L, BA29), claustrum (R...

In addition to CO2 insensitivity and reduced drive to breathe during sleep, CCHS patients often show impaired responses to transient blood pressure elevation. In adult man, fMRI studies indicate that the brain regions recruited for blood pressure regulation are extensive. We examined fMRI signal changes to a cold pressor challenge in selected brain sites of 7 CCHS children (3 male pairs, 8-15 yrs), ventilator-dependent only during sleep, no Hirschsprung's Disease) and in 7 age- and gender-matched controls. A series of 20 image slices (25 repetitions, Echo Planar technique) through the entire brain was collected during baseline and during application of a cold bag of deuterium oxide to the forehead. Baseline images were subtracted from experimental conditions, and the resultant difference images were subjected to multiple paired t-tests with Bonferroni correction (p<0.01) using MedX software. Brain areas responsive to the cold pressor challenge in controls included sites within the cerebellum, frontal corte...

Background: Previous studies have shown that quantitative MRI metrics are sensitive to microstructure and susceptibility changes in the SNc of parkinsonism patients. These are mainly lower SNc fractional anisotropy (FA), higher apparent transverse relax...

Individual hippocampal neurons selectively increase their firing rates in specific spatial locations. As a population, these neurons provide a decodable representation of space that is robust against changes to sensory- and path-related cues. This neural code is sparse and distributed, theoretically rendering it undetectable with population recording methods such as functional magnetic resonance imaging (fMRI). Existing studies nonetheless report decoding spatial codes in the human hippocampus using such techniques. Here we present results from a virtual navigation experiment in humans in which we eliminated visual- and path-related confounds and statistical limitations present in existing studies, ensuring that any positive decoding results would represent a voxel-place code. Consistent with theoretical arguments derived from electrophysiological data and contrary to existing fMRI studies, our results show that although participants were fully oriented during the navigation task, there was no statistical ...

Self-regulation of brain activity in humans based on real-time feedback of functional magnetic resonance imaging (fMRI) signal is emerging as a potentially powerful, new technique. Here, we assessed whether patients with Parkinson's disease (PD) are able to alter local brain activity to improve motor function. Five patients learned to increase activity in the supplementary motor complex over two fMRI sessions using motor imagery. They attained as much activation in this target brain region as during a localizer procedure with overt movements. Concomitantly, they showed an improvement in motor speed (finger tapping) and clinical ratings of motor symptoms (37% improvement of the motor scale of the Unified Parkinson's Disease Rating Scale). Activation during neurofeedback was also observed in other cortical motor areas and the basal ganglia, including the subthalamic nucleus and globus pallidus, which are connected to the supplementary motor area (SMA) and crucial nodes in the pathophysiology of PD. A PD cont...

We speak fluently by using auditory feedback, for which there exist many lines of evidence. The Lombard effect (Lane & Tranel, 1971), for instance, is a phenomenon in which a speaker involuntarily raises his or her vocal intensity in response to the lev...

Using noninvasive functional magnetic resonance imaging (fMRI) technique, we analyzed the responses in human area MT with regard to visual motion, color, and luminance contrast sensitivity, and retinotopy. As in previous PET studies, we found that area MT responded selectively to moving (compared to stationary) stimuli. The location of human MT in the present fMRI results is consistent with that of MT in earlier PET and anatomical studies. In addition we found that area MT has a much higher contrast sensitivity than that in several other areas, including primary visual cortex (V1). Functional MRI half- amplitudes in V1 and MT occurred at approximately 15% and 1% luminance contrast, respectively. High sensitivity to contrast and motion in MT have been closely associated with magnocellular stream specialization in nonhuman primates. Human psychophysics indicates that visual motion appears to diminish when moving color-varying stimuli are equated in luminance. Electrophysiological results from macaque MT sugg...

Over a dozen subregions are defined in the non-human primate auditory cortex. The translation of these areas onto the human brain, however, remains unclear. Recently the Human Connectome Project (HCP), using magnetic resonance images, has successfully d...

Brief neural activation creates a hemodynamic response function (HRF), a stereotypic manifestation of neurovascular coupling. A recent theory (Kim & Ress, Neuroimage, 2016) predicts that the HRF is created by a combination of flow and cerebral oxygen me...

The goal of this study was to use functional imaging to examine cortical plasticity and to identify neuronal activity changes in the network level after peripheral nerve injury. High resolution functional Magnetic Resonance Imaging (fMRI) has emerged as an important tool to study brain plasticity in humans and rodents in a non-invasive manner. In order to detect cortical reorganization, we have applied the common sciatic and the saphenous (the main nerves innervating the hindlimb) nerves injury model in rats, which was previously shown to induce short- as well as long-term intra-cortical plasticity changes at the cellular and at the network level. At different time points after surgery, fMRI was performed on an 11.7T animal MRI system on sham-operated rats, on sciatic nerve cut rats, and on rats where both the sciatic and saphenous nerves were cut. Electrical stimulation of the healthy hindlimb in the sham-operated and in the sciatic nerve cut rat groups resulted in normal contra-lateral somatosensory cort...