Bilateral Calcarine Gyrus Research Articles

Cerebral abnormalities in HIV-infected individuals with neurocognitive impairment revealed by fMRI

Although the combination antiretroviral treatment (cART) has considerably lowered the risk of HIV associated dementia (HAD), the incidence of neurocognitive impairments (NCI) has not decreased likely due to the insidious and slow progressive nature of HIV infection. Recent studies showed that the resting-state functional magnetic resonance imaging (rs-fMRI) is a prominent technique in helping the non-invasive analysis of neucognitive impairment. Our study is to explore the neuroimaging characteristics among people living with HIV (PLWH) with or without NCI in terms of cerebral regional and neural network by rs-fMRI, based on the hypothesis that HIV patients with and without NCI have independent brain imaging characteristics. 33 PLWH with NCI and 33 PLWH without NCI, recruited from the Cohort of HIV-infected associated Chronic Diseases and Health Outcomes, Shanghai, China (CHCDO) which was established in 2018, were categorized into the HIV-NCI and HIV-control groups, respectively, based on Mini-Mental State Examination (MMSE) results. The two groups were matched in terms of sex, education and age. Resting-state fMRI data were collected from all participants to analyze the fraction amplitude of low-frequency fluctuation (fALFF) and functional connectivity (FC) to assess regional and neural network alterations in the brain. Correlations between fALFF/FC values in specific brain regions and clinical characteristics were also examined. The results showed increased fALFF values in the bilateral calcarine gyrus, bilateral superior occipital gyrus, left middle occipital gyrus, and left cuneus in the HIV-NCI group compared to the HIV-control group. Additionally, increased FC values were observed between the right superior occipital gyrus and right olfactory cortex, bilateral gyrus rectus, and right orbital part of the middle frontal gyrus in the HIV-NCI group. Conversely, decreased FC values were found between the left hippocampus and bilateral medial prefrontal gyrus, as well as bilateral superior frontal gyrus. The study concluded that abnormal spontaneous activity in PLWH with NCI primarily occurred in the occipital cortex, while defects in brain networks were mostly associated with the prefrontal cortex. The observed changes in fALFF and FC in specific brain regions provide visual evidence to enhance our understanding of the central mechanisms underlying the development of cognitive impairment in HIV patients.

Functional and anatomical alterations in bilateral vestibulopathy: A multimodal neuroimaging study and clinical correlation.

To study multimodal neuroimaging study including resting state functional MRI (rs-fMRI), anatomical connectivity and brain morphology in patients with bilateral vestibulopathy (BVP) and relationship with clinical correlation. Thirteen patients with BVP (7 women; mean age ± SD = 63.5 ± 14.7 years, 22-80 years) and eighteen age and gender-matched controls were compared rs-fMRI and anatomical MRI. Also, we analyzed the relationship between multimodal neuroimaging and Dizziness Handicap Inventory score (DHI), Vestibular Disorders Activities of Daily Living Scale (VDRL), Geriatric Depression Scale (GDS) and Hospital Anxiety and Depression Scale (HADS). Compared with controls, BVP patients showed decreased functional connectivity among the key nodes of the salience network, auditory (including vestibular) network, bilateral posterior parahippocampal gyri, bilateral paracingulate gyri, and right frontoparietal network, and the anatomical connectivity in the right cerebellum, corpus callosum tapetum, and left fornix. BVP patients showed decreased gray matter volume in the bilateral parahippocampal gyri, right precentral gyrus, anterior cingulate gyrus, and right middle temporal gyrus and increased gray matter volume in the right superior frontal gyrus compared with controls. Correlation analyses showed rs-fMRI and clinical variables showed no significant result. DHI correlated negatively with anatomical connectivity in the bilateral frontal parahippocampal cingulum, corpus callosum, right inferior fronto-occipital fasciculus, bilateral fornix, and gray matter volumes in the bilateral middle occipital gyri, right superior occipital gyrus, left angular gyrus, and right cuneus in BVP. VADL correlated negatively with Anatomical connectivity in the corpus callosum, bilateral fornix, bilateral cerebellum, bilateral superior and anterior thalamic radiation, right inferior fronto-occipital fasciculus, bilateral fronto-parietal cingulum, right dentatoruburothalamic tract and gray matter volumes in the right angular gyri, bilateral parahippocampal gyri, right middle temporal gyrus, right cuneus, bilateral inferior occipital gyri, left middle occipital gyrus, right superior frontal gyrus, left fusiform gyrus, bilateral caudate, left cerebellar crus, and bilateral calcarine gyri in BVP. This study identified reductions in the volume of the hippocampus and alterations in functional and anatomical connectivity that concurs with previously established characteristics of BVP. The degree of disability can be inferred from the change in the connectivity and volume between vestibular cortical areas and their network.

Altered static and dynamic functional connectivity of habenula in first-episode, drug-naïve schizophrenia patients, and their association with symptoms including hallucination and anxiety.

The pathogenesis of schizophrenia (SCH) is related to the dysfunction of monoamine neurotransmitters, and the habenula participates in regulating the synthesis and release of dopamine. We examined the static functional connectivity (sFC) and dynamic functional connectivity (dFC) of habenula in first-episode schizophrenia patients using resting state functional magnetic resonance imaging (rs-fMRI) in this study. A total of 198 first-Episode, drug-Naïve schizophrenia patients and 199 healthy controls (HC) underwent rs-fMRI examinations. The sFC and dFC analysis with habenula as seed was performed to produce a whole-brain diagram initially, which subsequently were compared between SCH and HC groups. Finally, the correlation analysis of sFC and dFC values with the Positive and Negative Symptom Scale (PANSS) were performed. Compared with the HC groups, the left habenula showed increased sFC with the bilateral middle temporal gyrus, bilateral superior temporal gyrus, and right temporal pole in the SCH group, and the right habenula exhibited increased sFC with the left middle temporal gyrus, left superior temporal gyrus, and left angular gyrus. Additionally, compared with the HC group, the left habenula showed decreased dFC with the bilateral cuneus gyrus and bilateral calcarine gyrus in the SCH group. The PANSS negative sub-scores were positively correlated with the sFC values of the bilateral habenula with the bilateral middle temporal gyrus, superior temporal gyrus and angular gyrus. The PANSS general sub-scores were positively correlated with the sFC values of the right habenula with the left middle temporal gyrus and left superior temporal gyrus. The hallucination scores of PANSS were negatively correlated with the sFC values of the left habenula with the bilateral cuneus gyrus and bilateral calcarine gyrus; The anxiety scores of PANSS were positively correlated with the dFC values of the left habenula with the right temporal pole. This study provides evidence that the habenula of the first-episode schizophrenia patients presented abnormal static functional connectivity with temporal lobe and angular gyrus, and additionally showed weakened stability of functional connectivity in occipital lobe. This abnormality is closely related to the symptoms of hallucination and anxiety in schizophrenia, which may indicate that the habenula involved in the pathophysiology of schizophrenia by affecting the dopamine pathway.

Altered dynamic functional connectivity of auditory cortex and medial geniculate nucleus in first-episode, drug-naïve schizophrenia patients with and without auditory verbal hallucinations.

Background and objectiveAs a key feature of schizophrenia, auditory verbal hallucination (AVH) is causing concern. Altered dynamic functional connectivity (dFC) patterns involving in auditory related regions were rarely reported in schizophrenia patients with AVH. The goal of this research was to find out the dFC abnormalities of auditory related regions in first-episode, drug-naïve schizophrenia patients with and without AVH using resting state functional magnetic resonance imaging (rs-fMRI).MethodsA total of 107 schizophrenia patients with AVH, 85 schizophrenia patients without AVH (NAVH) underwent rs-fMRI examinations, and 104 healthy controls (HC) were matched. Seed-based dFC of the primary auditory cortex (Heschl's gyrus, HES), auditory association cortex (AAC, including Brodmann's areas 22 and 42), and medial geniculate nucleus (MGN) was conducted to build a whole-brain dFC diagram, then inter group comparison and correlation analysis were performed.ResultsIn comparison to the NAVH and HC groups, the AVH group showed increased dFC from left ACC to the right middle temporal gyrus and right middle occipital gyrus, decreased dFC from left HES to the left superior occipital gyrus, left cuneus gyrus, left precuneus gyrus, decreased dFC from right HES to the posterior cingulate gyrus, and decreased dFC from left MGN to the bilateral calcarine gyrus, bilateral cuneus gyrus, bilateral lingual gyrus. The Auditory Hallucination Rating Scale (AHRS) was significantly positively correlated with the dFC values of cluster 1 (bilateral calcarine gyrus, cuneus gyrus, lingual gyrus, superior occipital gyrus, precuneus gyrus, and posterior cingulate gyrus) using left AAC seed, cluster 2 (right middle temporal gyrus and right middle occipital gyrus) using left AAC seed, cluster 1 (bilateral calcarine gyrus, cuneus gyrus, lingual gyrus, superior occipital gyrus, precuneus gyrus and posterior cingulate gyrus) using right AAC seed and cluster 2 (posterior cingulate gyrus) using right HES seed in the AVH group. In both AVH and NAVH groups, a significantly negative correlation is also found between the dFC values of cluster 2 (posterior cingulate gyrus) using the right HES seed and the PANSS negative sub-scores.ConclusionsThe present findings demonstrate that schizophrenia patients with AVH showed multiple abnormal dFC regions using auditory related cortex and nucleus as seeds, particularly involving the occipital lobe, default mode network (DMN), and middle temporal lobe, implying that the different dFC patterns of auditory related areas could provide a neurological mechanism of AVH in schizophrenia.

Network Reconfiguration Among Cerebellar Visual, and Motor Regions Affects Movement Function in Spinocerebellar Ataxia Type 3.

BackgroundSpinocerebellar ataxia type 3 (SCA3) is a rare movement disorder characterized with ataxia. Previous studies on movement disorders show that the whole-brain functional network tends to be more regular, and these reconfigurations correlate with genetic and clinical variables.MethodsTo test whether the brain network in patients with SCA3 follows a similar reconfiguration course to other movement disorders, we recruited 41 patients with SCA3 (mean age = 40.51 ± 12.13 years; 23 male) and 41 age and sex-matched healthy individuals (age = 40.10 ± 11.56 years; 24 male). In both groups, the whole-brain network topology of resting-state functional magnetic resonance imaging (rs-fMRI) was conducted using graph theory, and the relationships among network topologies, cytosine-adenine-guanine (CAG) repeats, clinical symptoms, and functional connectivity were explored in SCA3 patients using partial correlation analysis, controlling for age and sex.ResultsThe brain networks tended to be more regular with a higher clustering coefficient, local efficiency, and modularity in patients with SCA3. Hubs in SCA3 patients were reorganized as the number of hubs increased in motor-related areas and decreased in cognitive areas. At the global level, small-worldness and normalized clustering coefficients were significantly positively correlated with clinical motor symptoms. At the nodal level, the clustering coefficient and local efficiency increased significantly in the visual (bilateral cuneus) and sensorimotor (right cerebellar lobules IV, V, VI) networks and decreased in the cognitive areas (right middle frontal gyrus). The clustering coefficient and local efficiency in the bilateral cuneus gyrus were negatively correlated with clinical motor symptoms. The functional connectivity between right caudate nucleus and bilateral calcarine gyrus were negatively correlated with disease duration, while connectivity between right posterior cingulum gyrus and left cerebellar lobule III, left inferior occipital gyrus and right cerebellar lobule IX was positively correlated.ConclusionOur results demonstrate that a more regular brain network occurred in SCA3 patients, with motor and visual-related regions, such as, cerebellar lobules and cuneus gyrus, both forayed neighbor nodes as “resource predators” to compensate for normal function, with motor and visual function having the higher priority comparing with other high-order functions. This study provides new information about the neurological mechanisms underlying SCA3 network topology impairments in the resting state, which give a potential guideline for future clinical treatments.Clinical Trial Registration[www.ClinicalTrials.gov], identifier [ChiCTR1800019901].

Altered Functional Connectivity of the Nucleus Accumbens Network Between Deficit and Non-deficit Schizophrenia.

Deficit schizophrenia (DS), which is marked by stable negative symptoms, is regarded as a homogeneous subgroup of schizophrenia. While DS patients have structurally altered nucleus accumbens (NAcc) compared to non-deficit schizophrenia (NDS) patients and healthy individuals, the investigation of NAcc functional connectivity (FC) with negative symptoms and neurocognition could provide insights into the pathophysiology of schizophrenia. 58 DS, 93 NDS, and 113 healthy controls (HCs) underwent resting-state functional magnetic resonance (rsfMRI). The right and left NAcc were respectively used as seed points to construct the functional NAcc network in whole-brain FC analysis. ANCOVA compared the differences in NAcc network FC and partial correlation analysis explored the relationships between altered FC of NAcc, negative symptoms and neurocognition. Compared to HCs, both DS and NDS patients showed decreased FC between the left NAcc (LNAcc) and bilateral middle cingulate gyrus, and between the right NAcc (RNAcc) and right middle frontal gyrus (RMFG), as well as increased FC between bilateral NAcc and bilateral lingual gyrus. Moreover, the FC between the LNAcc and bilateral calcarine gyrus (CAL) was lower in the DS group compared to NDS patients. Correlation analysis indicated that FC value of LNAcc-CAL was negatively correlated to negative symptoms. Furthermore, aberrant FC values within the NAcc network were correlated with severity of clinical symptoms and neurocognitive impairments in DS and NDS patients. This study demonstrated abnormal patterns of FC in the NAcc network between DS and NDS. The presence of altered LNAcc-CAL FC might be involved in the pathogenesis of negative symptoms in schizophrenia.

Primary visual cortex of the brain is associated with optic nerve head changes in neuromyelitis optica spectrum disorders

ObjectiveTo explore the association between the primary visual cortex in the brain and optic nerve head changes, ONH, (structural thickness and microvascular changes) in neuromyelitis optica spectrum disorder (NMOSD). MethodsNineteen patients who were aquaporin-4 (AQP-4) seropositive NMOSD patients and twenty-two healthy controls (HC) were enrolled for this cross-sectional study. Optical coherence tomographic angiography (OCT-A) was used to image and measure the capillaries density (RPC, radial peripapillary capillaries) and structural thickness (pRNFL, peripapillary retinal nerve fiber layer) around the optic nerve head. A resting-state functional magnetic resonance imaging was used to image and evaluate the gray matter volume (GMV) and functional connectivity (FC) the brain of each participant. We assessed the primary visual cortex (lingual gyrus, calcarine sulcus and thalamus) of the brain. ResultsChanges in RPC density showed a significant association (P < 0.05) with FC of the right lingual gyrus, bilateral calcarine gyrus and left thalamus respectively. pRNFL thickness showed significant association with FC of the right lingual gyrus (Rho = 0.374, P = 0.016), right calcarine gyrus (Rho = 0.355, P = 0.023) and left thalamus (Rho = 0.376, P = 0.015) respectively. ConclusionsVisual impairment, structural and microvascular changes around optic nerve head is associated with the functional visual networks in NMOSD. Our report suggests that structural and microvascular changes around the ONH reflect the changes in the primary visual cortex of the brain.

Brain functional connectivity during storage based on resting state functional magnetic resonance imaging with synchronous urodynamic testing in healthy volunteers.

The aim of the study was to elucidate the correlation between spatially distinct brain areas with a full bladder from the perspective of functional connectivity using resting-state functional magnetic resonance imaging (rs-fMRI) with simultaneous urodynamic testing in healthy volunteers. The brain regions with full and empty bladders were reported via rs-fMRI using a 3T magnetic resonance system. Then, we identified brain regions that are activated during bladder filling by calculating the amplitude of low-frequency fluctuation (ALFF) values using brain imaging software (DPABI and SPM8) and empirically derived six regions of interest (ROI) from analysis of activation were used as seeds for resting-state functional connectivity (rs-FC) analysis with the rest of the brain to examine differences in the two conditions. Statistical analysis was performed with a paired t-test and statistical significance was defined as a P < 0.01. Twenty-two healthy volunteers (11 men and 11 women) 35-64years of age were enrolled. The rs-fMRI scans of 22 healthy volunteers were analyzed. After motion correction, two subjects were excluded. Meaningful data were obtained on 20 of these subjects. Compared with an empty bladder, functional connection enhancement was noted mainly in the right inferior orbitofrontal cortex and bilateral calcarine gyrus, the left lingual gyrus, left fusiform gyrus, left superior occipital gyrus, right insula, right inferior temporal gyrus, superior parietal lobe, left insula, right lingual gyrus, right fusiform gyrus, left parahippocampal gyrus, right inferior temporal gyrus, superior parietal lobe, left calcarine gyrus, bilateral lingual gyrus, prefrontal cortex, including the middle frontal gyrus and superior frontal gyrus, the right middle temporal gyrus, bilateral posterior cingulate cortex, and right precuneus. The decrease in functional connection was mainly located in the right inferior orbitofrontal cortex, prefrontal cortex, including the superior frontal gyrus, orbitofrontal cortex, and anterior cingulate cortex, the left inferior orbitofrontal cortex, right insula, middle occipital gyrus, angular gyrus, inferior frontal gyrus, right insula, middle temporal gyrus, inferior parietal lobe, middle occipital gyrus, supplementary motor area, superior frontal gyrus, left insula, bilateral posterior cingulate cortex, bilateral precuneus, middle occipital gyrus, and right middle temporal lobe. There were significant changes in the functional connectivity of the brain between full and empty bladders in healthy volunteers, which suggests that the central neural processes involved in storage needs brain areas with integrated control. These findings are strong evidence for physicians to consider brain responses in urine storage and offer the provision of some normative data.

Alterations in the Brain Structure and Functional Connectivity in Aquaporin-4 Antibody-Positive Neuromyelitis Optica Spectrum Disorder.

PurposeTo investigate the mechanisms underlying the gray matter volume (GMV) and functional connectivity (FC) changes in aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (NMOSD) patients.MethodsThis cross-sectional study consisted of 21 patients with aquaporin-4 antibody-positive NMOSD and 22 age- and sex-matched healthy controls. All participants underwent cerebral magnetic resonance imaging and testing each individual’s visual acuity was done.ResultsNeuromyelitis optica spectrum disorder patients showed significantly reduced GMV in the left calcarine, left thalamus and right lingual gyrus of the NMOSD patients when compared to HC (P < 0.05). NMOSD patients showed significantly decreased FC values (P < 0.05) in both the left and right calcarine, right lingual gyrus and left thalamus, respectively, when compared to HC. We also observed a positive correlation between the FC values of the left thalamus, bilateral calcarine gyrus and the visual acuity, respectively (P < 0.05). Furthermore, a negative association was seen between the duration of the disease, frequency of optic neuritis, and the FC values in the lingual gyrus, bilateral calcarine gyrus, and right lingual gyrus, respectively (P < 0.05).ConclusionReduced visual acuity and frequency of optic neuritis are associated with alterations in the GMV and FC in NMOSD. Our current study, which provides imaging evidence on the impairment involved in NMOSD, sheds light on pathophysiological responses of optic neuritis attack on the brain especially on the visual network.

Altered Spontaneous Regional Brain Activity in the Insula and Visual Areas of Professional Traditional Chinese Pingju Opera Actors.

Recent resting-state fMRI studies have revealed neuroplastic alterations after long-term training. However, the neuroplastic changes that occur in professional traditional Chinese Pingju opera actors remain unclear. Twenty professional traditional Chinese Pingju opera actors and 20 age-, sex-, and handedness-matched laymen were recruited. Resting-state fMRI was obtained by using an echo-planar imaging sequence, and two metrics, amplitude of low frequency fluctuation (ALFF) and regional homogeneity (ReHo), were utilized to assess spontaneous neural activity during resting state. Our results demonstrated that compared with laymen, professional traditional Chinese Pingju actors exhibited significantly decreased ALFF in the bilateral calcarine gyrus and cuneus; decreased ReHo in the bilateral superior occipital and calcarine gyri, cuneus, and right middle occipital gyrus; and increased ReHo in the left anterior insula. In addition, no significant association was found between spontaneous neural activity and Pingju opera training duration. Overall, the changes observed in spontaneous brain activity in professional traditional Chinese Pingju opera actors may indicate their superior performance of multidimensional professional skills, such as music and face perception, dancing, and emotional representation.

Altered cortical activation and connectivity patterns for visual attention processing in young adults post-traumatic brain injury: A functional near infrared spectroscopy study.

This study aimed at understanding the neurobiological mechanisms associated with inattention induced by traumatic brain injury (TBI). To eliminate the potential confounding caused by the heterogeneity of TBI, we focused on young adults postsports-related concussion (SRC). Functional near-infrared spectroscopy (fNIRS) data were collected from 27 young adults post-SRC and 27 group-matched normal controls (NCs), while performing a visual sustained attention task. Task responsive cortical activation maps and pairwise functional connectivity among six regions of interest were constructed for each subject. Correlations among the brain imaging measures and clinical measures of attention were calculated in each group. Compared to the NCs, the SRC group showed significantly increased brain activation in left middle frontal gyrus (MFG) and increased functional connectivity between right inferior occipital cortex (IOC) bilateral calcarine gyri (CG). The left MFG activation magnitude was significantly negatively correlated with the hyperactive/impulsive symptom severity measure in the NCs, but not in the patients. The right hemisphere CG-IOC functional connectivity showed a significant positive correlation with the hyperactive/impulsive symptom severity measure in patients, but not in NCs. The current data suggest that abnormal left MFG activation and hyper-communications between right IOC and bilateral CG during visual attention processing may significantly contribute to behavioral manifestations of attention deficits in patients with TBI.

Nonlinear modulation of interacting between COMT and depression on brain function

BackgroundThe catechol-O-methyltransferase (COMT) gene is related to dopamine degradation and has been suggested to be involved in the pathogenesis of major depressive disorder (MDD). However, how this gene affects brain function properties in MDD is still unclear. MethodsFifty patients with MDD and 35 cognitively normal participants underwent a resting-state functional magnetic resonance imaging scan. A voxelwise and data-drive global functional connectivity density (gFCD) analysis was used to investigate the main effects and the interactions of disease states and COMT rs4680 gene polymorphism on brain function. ResultsWe found significant group differences of the gFCD in bilateral fusiform area (FFA), post-central and pre-central cortex, left superior temporal gyrus (STG), rectal and superior temporal gyrus and right ventrolateral prefrontal cortex (vlPFC); abnormal gFCDs in left STG were positively correlated with severity of depression in MDD group. Significant disease×COMT interaction effects were found in the bilateral calcarine gyrus, right vlPFC, hippocampus and thalamus, and left SFG and FFA. Further post-hoc tests showed a nonlinear modulation effect of COMT on gFCD in the development of MDD. Interestingly, an inverted U-shaped modulation was found in the prefrontal cortex (control system) but U-shaped modulations were found in the hippocampus, thalamus and occipital cortex (processing system). ConclusionOur study demonstrated nonlinear modulation of the interaction between COMT and depression on brain function. These findings expand our understanding of the COMT effect underlying the pathophysiology of MDD.

Altered intra- and interregional synchronization in the absence of the corpus callosum: a resting-state fMRI study.

Agenesis of the corpus callosum (AgCC) can result in subtle to severe cognitive deficits. Individuals with impaired cognition often show abnormalities on resting-state functional magnetic resonance imaging (rs-fMRI). This study used rs-fMRI to investigate changes in regional homogeneity (ReHo) and functional connectivity (FC) among individuals with AgCC. AgCC individuals (n=10) and age-, sex-, and education-matched healthy control subjects (n=19) were included in this study. The ReHo values were calculated to represent spontaneous brain activity. The regions which showed altered ReHo were selected as seeds to compare FC with the whole brain between the AgCC group and the healthy control group. Compared with healthy control subjects, the AgCC individuals had increased ReHo in the left anterior cingulate gyrus, left rolandic operculum, and right precuneus and decreased ReHo in the right calcarine, right cingual gyrus and right cuneus gyrus. The right calcarine and the right lingual gyrus in the AgCC exhibited decreased FC with bilateral cuneus, superior occipital gyrus, Rolandic operculum, superior temporal gyrus, posterior central gyrus, and midcingulate gyrus.The right cuneus gyrus in the AgCC individuals exhibited decreased FC with the bilateral calcarine gyrus, left cuneus, and left superior occipital gyrus. Our study revealed several subareas within the visual cortex exhibited remarkable abnormalities of spontaneous brain activity and decreased FC with the higher-order cognitive cortex.The abnormalities of ReHo and FC in AgCC individuals may provide new insights into the neurological pathophysiology.

Anterior and posterior default mode networks impairments in minimal hepatic encephalopathy

To investigate the functional connectivity (FC) impairments within anterior and posterior default mode networks (aDMN and pDMN) for cirrhosis with minimal hepatic encephalopathy (MHE), and to analyze relationship between DMNs alterations with neurocognitive impairments. From March 2009 to December 2011, a total of 43 cirrhotic patients without MHE (NMHE groups), 32 cirrhotic patients with current MHE (MHE groups), and 21 healthy controls were recruited in this study. All resting-state fMRI datasets were preprocessed and normalized into standard brain space. Two universal templates for aDMN and pDMN were applied to generate spatial patterns for aDMN and pDMN for each participate by dual regression. One sample t test were analyzed within groups, and one way ANOVA (analysis of variance) were performed to calculate the different FCs within aDMN and pDMN among groups. Additional correlation analysis was performed between different FCs within two DMNs and behavior scores. Within aDMN, FC of MHE patients were significantly deceased than controls and NMHE groups in right superior frontal gyrus (SFG)/ bilateral medial frontal gyrus (MFG); while within pDMN, FC of MHE patients were significantly increased than controls and NMHE groups in right superior temporal gyrus (STG)/ middle temporal gyrus (MTG) and left cuneus/ bilateral calcarine gyri (one way ANOVA, P<0.01, cluster sizes>40, AlphaSim correction). The FC alterations in those region were significantly correlated with neurocognitive test scores (Pearson correlation coefficient, P<0.05). Dual regression based aDMN and pDMN method was firstly applied to investigated functional connectivity impairments in MHE patients' brain. Functional deficits were endogenous within aDMN, while functional connectivity was compensatory enhancements within pDMN. These compensatory enhancements indicated that patients with current MHE had the potential to additionally recruit more neurological resource to accomplish the specific actions. Therefore, the alterations of dual regression based aDMN and pDMN can be potential neuroimaging biomarkers for MHE studies.

Functional connectivity of reward and cognitive control network in chronic heroin addicts: a resting-state functional MRI study

Objective To explore the changes and effect of functional connectivity(FC) of reward network in chronic heroin addicts(HA) using resting-state fMRl(rs-fMRI). Methods rs-fMRI was performed on 26 chronic heroin addicts(HA group) and 25 matched normal volunteers(control group).The rs-fMRI data were proceeded by usingrs-fMRI(DPARSF) software on Matlab 2009a. Bilateral nucleus accumbens(Nacc) were set as ROIs. Then the mean time series of ROI were compared with other voxels within the brain by the rs-fMRI data analysis toolkit(REST) . Intra-and inter-group analysis was performed with single sample and two sample t test respectively. The association of intensity of FC in brain regions and the duration/doses of heroin consumption was investigated. Results In HA group, positiveresting-state FC compared with the ROIs was found in frontal gyms, dorsal striatum, thalamus and pons, while temporal lobe, negative found in part of parietal cortex and occipital cortex, part of dorsal lateral prefrontal cortex and cerebellum. Within control group, positive FC compared with the ROIs was found in frontal gyms, dorsal striatum, thalamus, hippocampal gyrus and pons, occipital cortex, negative FC with ROIs found in part of dorsal lateral prefrontal cortex and cerebellum(P 26). Compared with the control group,the FC between the right Nacc and the bilateral calcarinegyrus, left middle occipital gyrus (voxel numbe r=31, 28, 47; t=3.99, 3.74, 3.74; and P 0.05) . Conclusion The abnormal interaction between Nacc and the regions involved in cognitive control and visual spatial attention may contribute to the heroin addiction. Key words: Heroin dependence; Magnetic resonance imaging

Functional connectivity of amygdala in refractory epilepsy:a resting-state functional study of magnetic resonance imaging

To explore the functions of amygdala functional connectivity in the pathogenesis of refractory epilepsy with resting-state functional magnetic resonance imaging (RS-fMRI). A total of 19 patients with refractory epilepsy were recruited from August 2013 to June 2014. And 19 healthy persons were selected as the controls.No obvious epileptogenic lesions of intracranial structures were found on multi-modal neuroimaging.Ictal and interictal epileptic activities on long-term video electroencephalogram (EEG) showed spine spread spike and wave in bilateral cerebral hemispheres. All fMRI data were preprocessed after RS-fMRI scanning. Then left and right amygdalas were selected as regions of interest (ROIs) for calculating the linear correlation between amygdala and whole brain. As relative to the control group, the changes of brain areas in functional connectivity were examined for the intractable epilepsy group. Compared with the controls, left amygdala in refractory epilepsy group showed increased functional connectivity with bilateral fusiform gyrus, bilateral calcarine gyrus and right lingual, on the contrary decreased functional connectivity with bilateral cuneus, bilateral precuneus, bilateral caudatas and left thalamus.However, right amygdala demonstrated increased functional connectivity with bilateral calcarine gyrus and bilateral linguals, but decreased functional connectivity with bilateral caudatas and left putamen (P < 0.05). Altered functional connectivity of amygdala reflects its dysfunction in refractory epilepsy patients. It suggested that amygdala is an important component of "epileptic network" participating in the occurrence and development of refractory epilepsy.