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Object: Resting functional magnetic resonance imaging and ratio low-frequency amplitude methods were used to investigate the characteristics of brain functional changes in chronic low back pain. Method: Resting fMRI data were collected from 12 volunteers with chronic low back pain (4 males and 8 females, 47.9±6.1 years old) using a 3.0T magnetic resonance imager. Pretreatment and ALFF analysis were performed using DPARSF software, and single-sample t-test was performed in SPM8 to observe the changes of functional magnetic resonance in patients with chronic low back pain. Result: In patients with chronic low back pain, the resting ALFF values were significantly higher than the whole brain mean brain area, which mainly involved the anterior and posterior anterior gyrus, the median frontal gyrus, the medial frontal gyrus, the superior temporal gyrus, the lower marginal gyrus, and the back. Conclusion: Changes in brain function in patients with chronic low back pain were consistent with changes in cognition, mood, memory.

The current study investigated topographies and causality profiles of left hippocampus-related brain systems identified with resting state functional correlations in mild TBI as well as healthy individuals. We found a set of significantly connected brain regions (nodes) involved in the left hippocampal intrinsic network and altered causality profiles among the identified nodes. Functional connectivity analysis showed that the hippocampal network concerning episodic memory in mild TBI survivors (mTBI) became increasingly larger than that in normal controls, especially the medial frontal gyrus (MeFG), middle frontal gyrus (MFG), and temporo-parietal conjunction area. Granger causality analysis (GCA) illustrated increased bilateral causal connectivity and ipsilateral interaction in the right hemisphere, which was in contrast to intensive ipsilateral causal connection in the left hemisphere in normal controls. We postulated that the dysfunctioned hippocampus and ineffective compensation strategy resulted in a weakening episodic memory in mTBI patients.

This paper presents an automatic, non-invasive method for detecting Autism Spectrum Disorders (ASD) among males using structural Magnetic Resonance Imaging. Whole brain Voxel Based Morphometry (VBM) analysis is first used to identify the brain regions that are affected for ASD patients and gray matter probability in these regions are used as features for classification. In contrast to existing studies which are small in scale, this paper presents a large scale study using the publicly available dataset from Autism Brain Imaging Data Exchange. Taking a cue from genetic studies which indicate that ASD manifests differently among males and females, this paper considers males only. Even among males, this study shows that better classification accuracy can be achieved by considering adult and adolescent males separately. By using a Metacognitive Radial basis Function Network classifier, classification accuracy of 59.73%, 61.49% and 70.41% is achieved when considering all males, adolescent males and adult males respectively. This is about (5 to 10%) higher than Support Vector Machine classifier which is commonly used in literature for this problem and about (6 to 15%) higher than Naive Bayes classifier. It is also found that all three classifiers perform better when considering adult and adolescent males separately instead of considering all males together underscoring the need to consider different age-groups separately for ASD detection. VBM analysis indicates that the precentral gyrus, motor cortex, medial frontal gyrus and the paracentral lobule areas are possibly affected for adolescent males with ASD while the superior frontal gyrus and the frontal eye fields areas are possibly affected for adult males with ASD.

Anxiety is usually associated with dysfunction of cognitive control. The aim of the present study is to examine whether high anxious individuals have a damage of cognitive control function in a standard response inhibition task, Go/Nogo-paradigm, and to investigate its neural correlates with event-related potentials (ERPs). We focused on the N2 and P3 components in the difference wave between NoGo condition and Go condition, which is considered to reflect different processing stage of response inhibition. The P3 component was mainly influenced by trait anxiety, showing the reduction in HTA group. Using the standardised Low Resolution Electromagnetic Tomography method (sLORETA), we found that the reduced P3 of difference wave in HTA group was associated with the medial frontal gyrus and superior frontal gyrus. Therefore, the attenuation of response inhibition in anxiety is likely mediated by the decreased activation of frontal area.

Imaging cerebral glucose metabolism with positron emission tomography (PET) has been widely used in studying Alzheimer's disease (AD) and mild cognitive impairment (MCI). In this study, we used fluoro-deoxyglucose (FDG) PET images to investigate reduced glucose metabolism in 90 AD subjects, 90 MCI subjects and 90 healthy elderly normal controls (NC). Compared to NC, the AD showed a significant hypometabolism in left and right middle temporal, left cingulate gyrus, medial frontal gyrus and left parahippocampal gyrus. Compared to NC, the MCI showed a significant hypometabolism in the right inferior temporal gyrus and right fusiform gyrus. Compared to MCIs, the AD also showed a significant hypometabolism in left and right middle temporal, left cingulate gyrus, left angular gyrus and right parahippocampal gyrus. This study demonstrates the different cerebral metabolic patterns of AD, MCI and controls. It also shows that glucose metabolism is a sensitive measure of change in cognition and functional ability in AD and MCI, and that might be valuable in predicting future cognitive decline.

Functional magnetic resonance imaging (fMRI) is one of the most recently developed forms of neuroimaging, uses MRI to measure the haemodynamic response related to neural activity. In the present study, we developed a tactile orientation stimulator using under high magnetic environment. The device is MRI-compatible and can serve to investigate the underlying neural mechanisms of tactile orientation cognition and discrimination. The primary components of the tactile orientation presentation system include a computer (system control), seven tactile orientation domes, two ultrasonic motors (tactile stimuli presentation), a motor controller and a reaction key. We evaluated the function, precision and performance of the system in a magnetic field. The results showed that the device performance is unaffected by the magnetic field, nor does the device interfere with the magnetic field, making it usable with fMRI. Furthermore, a simple button press fMRI experiment was conducted using the system. Compared to the baseline, the most prominent activation areas evoked by the button press task were in the primary motor area on the right precentral gyrus, bilateral medial frontal gyrus, putamen and cerebellum. In summary, these results indicated that the brain activation can be reliably detected with the present device.

Objective: To explore regional brain activity changes during neural processing of human stereopsis by subtracting and reverse subtracting. Methods: Ten healthy volunteers participated in our fMRI experiments. Each subject performed two different vision-related tasks: plane figure and stereogram stimulations. After preprocessing, data were analyzed with SPM 99 software. We employed reverse subtracting method to obtain the group averaged deactivation maps. Results: There are two major findings in our study. The deactivated brain areas appear to be task dependence. Of plane figure stimuli, deactivation were mainly centered on default mode network, and with stereogram stimuli induced deactivation in regions of fusiform gyrus, thalamus and claustrum. Furthermore, task independent deactivation were observed in the medial frontal gyrus, superior temporal gyrus and insula. Conclusion: Our data further supported the notion that default mode network activity does exist during resting state. Nevertheless, stimulus is an important contribution to deactivation and should be considered when exploring the phenomenon of deactivation. Brain resources can be allocated automatically and continuously according to different task performance.

In this study, P300 that induced by visual stimuli was examined with simultaneous EEG/fMRI. For the purpose of combine the best temporary resolution with the best special resolution together to estimate the cortical network, event-related analysis contributed to this methodological trial. A 64 channel MRI-compatible EEG amplifier (BrainAmp: made of Brain Production GmbH, Germany) was used in the measurement simultaneously with fMRI scanning. The sampling rate of raw EEG was 5 kHz, and the MRI noise reduction was performed. EEG recording synchronized with MRI scan by original stimulus system, and an oddball paradigm (3 letters presentation: 'T'=Standard with 56% appearances proportion, 'C'=Target with 22% appearances proportion, 'P'=Novel with 22% appearances proportion) was performed. Presentation time of visual stimulus is 240ms and inter-stimulus interval (ISI>650ms) is variable. Every subject underwent a 1344s session, there are eight 156s stimul-blocks which including 26pairs of stimulation and eight 12s interval. MRI scan interval (3s) is synchronized to inter-stimulus interval (3s) in the whole session. In order that activations of P300 can be scanned by each slice scanning-phase, the appearance of visual stimuli shifted from start to the end of each MRI scan randomly. After P300 segmentation, the timing of P300 was exported to event-related analysis of fMRI data with SPM99 software. In the 7 subjects group study, the significant activations appear in the inferior occipital gyrus of both cerebrum, superior and medial frontal gyrus of both cerebrum, precentral gyrus of both cerebrum, left superior temporal gyrus, and left inferior parietal lobule. Our method successfully demonstrated a cortical network that related with P300 event during visual cognition. The spatial information of the cortical regions provides a possible function of P300 that activated at the frontal and parietal sites as an attention control for Logical Judgment process in the visual cognition. By using a simultaneous fMRI and EEG, even a small phase synchronization (P300 event-related) is good enough to extract the functional relevant networking of regions, not only in the superficial, but also deeper brain regions. This method could be feasible for identifying networks that are integrated with event.