Left Medial Superior Frontal Gyrus Research Articles

Left hemispheric \u03b1 band cerebral oscillatory changes correlate with verbal memory

Event-related synchronisation (ERS) and event-related desynchronisation (ERD) have been observed via magnetoencephalography (MEG) in the language-dominant hemisphere. However, the relationship between ERS/ERD and clinical language indices is unclear. Therefore, the present study evaluated brain activity utilising MEG during a verb generation task in 36 subjects and determined ERS/ERD power values in θ, α, β, low γ and high γ frequency bands. To measure clinical language indices, we adopted Wechsler Memory Scale-revised. We observed ERD in the α band from the bilateral occipital to the left central brain region, in the β band from the bilateral occipital to the left frontal region and in the low γ band a high-power signal in the left frontal region. We also observed ERS in the θ band in bilateral frontal region and in the high γ band in bilateral occipital region. Furthermore, we found a significant negative correlation between α-band ERD power at the left postcentral gyrus and medial superior frontal gyrus and verbal memory score (correlation coefficients = − 0.574 and − 0.597, respectively). These results suggest that individuals with lower linguistic memory have less desynchronised α-band ERD power and α-band ERD power in the left hemisphere may be a neurophysiological biomarker for verbal memory.

Cerebral blood flow alterations in hemodialysis patients with and without restless legs syndrome: an arterial spin labeling study.

Hemodialysis with restless legs syndrome (HD-RLS) is associated with alterations in neuronal function, the blood-brain barrier and iron deposition, thus affecting cerebral metabolism and perfusion. This study utilized three-dimensional arterial spin labeling (ASL) to identify HD-RLS-related perfusion patterns and potential relationships with disease severity. Twenty-six HD-RLS patients, 30 hemodialysis patients without restless legs syndrome (HD-nRLS) and 30 age-, sex-, and education-matched healthy controls were included in this study. One-way analysis of covariance and post hoc analyses were used to assess differences in cerebral blood flow (CBF) values, demographics and clinical data among the three groups. Pearson's correlation analysis was conducted between altered CBF values in the HD-RLS group and clinical data. Compared with HD-nRLS patients, HD-RLS patients showed increased CBF in the right primary motor cortex (false discovery rate [FDR]-corrected P < 0.05). Compared with the normal controls, both HD subgroups (i.e., those with and without RLS) exhibited consistent CBF changes, including increased CBF in the left medial superior frontal gyrus and bilateral thalamus and decreased CBF in the left insular cortices (FDR-corrected P < 0.05). This abnormal hyperperfusion in the sensorimotor cortex and basal ganglia provides evidence for a sensory processing disorder in RLS that may be involved in the pathogenesis of RLS in HD patients.

The Anterior-posterior Functional Connectivity Disconnection in the Elderly with Subjective Memory Impairment and Amnestic Mild Cognitive Impairment.

Subjective Memory Impairment (SMI) may tremendously increase the risk of Alzheimer's Disease (AD). The full understanding of the neuromechanism of SMI will shed light on the early intervention of AD. In the current study, 23 Healthy Controls (HC), 22 SMI subjects and 24 amnestic Mild Cognitive Impairment (aMCI) subjects underwent the comprehensive neuropsychological assessment and the resting-state functional magnetic resonance imaging scan. The difference in the connectivity of the Default Mode Network (DMN) and Functional Connectivity (FC) from the Region of Interest (ROI) to the whole brain were compared, respectively. The results showed that HC and SMI subjects had significantly higher connectivity in the region of the precuneus area compared to aMCI subjects. However, from this region to the whole brain, SMI and aMCI subjects had significant FC decrease in the right anterior cingulum, left superior frontal and left medial superior frontal gyrus compared to HC. In addition, this FC change was significantly correlated with the cognitive function decline in participants. Our study indicated that SMI subjects had relatively intact DMN connectivity but impaired FC between the anterior and posterior brain. The findings suggest that long-distance FC is more vulnerable than the short ones in the people with SMI.

Atrophic Corpus Callosum Associated with Altered Functional Asymmetry in Major Depressive Disorder.

PurposeImpairments in intra- and inter-hemispheric information transfer circuits have been reported in patients with major depressive disorder (MDD). However, the specific anomalous connection (intra- and/or inter-hemispheric) and hemisphere (left and/or right) in which this connection plays a more dominant role in the pathogenic mechanism underlying MDD are still poorly understood.Patients and MethodsStructural magnetic resonance imaging and resting-state functional magnetic resonance imaging were performed in 33 patients with MDD and 33 healthy controls. The intra- and inter-hemispheric functional connectivity (FC) strength in the default mode network areas and volume of the callosal subregions were computed using independent samples t-tests. The partial correlations between the volumes and FCs were also computed.ResultsThe patients with MDD had smaller volumes in the genu of the corpus callosum than the controls. The intrahemispheric FCs of the bilateral posterior cingulate gyrus, left precuneus, left medial superior frontal gyrus, left medial orbitofrontal gyrus, left angular gyrus and left middle temporal gyrus, and interhemispheric FCs of the bilateral posterior cingulate gyrus in the patients with MDD were lower than those in the controls. Moreover, the intrahemispheric FCs of the precuneus and interhemispheric FCs of middle frontal gyrus, orbital middle frontal gyrus, and anterior cingulate gyrus in the patients with MDD showed right-lateralized asymmetry, which were opposite from the asymmetry patterns observed in the controls. The functional asymmetry of the anterior cingulate gyrus was correlated with the volume of the genu of the corpus callosum and disease duration.ConclusionThese findings provide robust evidence that intra- and inter-hemispheric disconnections are involved in MDD, and that functional disruptions in the left hemisphere may be more relevant to the pathophysiology of MDD. Furthermore, imbalanced interhemispheric exchanges may contribute to the anatomical deficits in the corpus callosum in patients with MDD.

Shared gray matter alterations in individuals with diverse behavioral addictions: A voxel-wise meta-analysis.

Background and aimsNumerous studies on behavioral addictions (BAs) have reported gray matter (GM) alterations in multiple brain regions by using voxel-based morphometry (VBM). However, findings are poorly replicated and it remains elusive whether distinct addictive behaviors are underpinned by shared abnormalities. In this meta-analysis, we integrated VBM studies on different BAs to investigate common GM abnormalities in individuals with BAs.MethodsWe performed a systematic search up to January 2019 in several databases for VBM studies investigating GM differences between individuals with BAs and healthy controls. The reference lists of included studies and high-quality reviews were investigated manually. Anisotropic effect-size signed differential mapping was applied in this meta-analysis.ResultsTwenty studies including 505 individuals with BAs and 564 healthy controls met the inclusion criteria. Compared with healthy controls, individuals with BAs showed GM atrophy in the left anterior cingulate (extending to the left medial superior frontal gyrus and bilateral orbitofrontal gyrus), right putamen and right supplementary motor area. Subgroup analysis found heterogeneity in gender and subtypes of BAs. Meta-regression revealed that GM decreases in the left anterior cingulate and right supplementary motor area were positively correlated with addictive severity. Higher impulsivity was associated with smaller volume of the left anterior cingulate.Discussion and conclusionsOur findings on BAs were mainly derived from internet gaming disorder (IGD) and pathological gambling (PG) studies, preliminarily suggesting that GM atrophy in the prefrontal and striatal areas might be a common structural biomarker of BAs.

Altered regional gray matter volume in Chinese female patients with bulimia nervosa.

BackgroundBulimia nervosa (BN) is a psychiatric disorder with unclear pathophysiology. Several studies have associated BN with structural and functional changes in the brain, but findings have been inconsistent. Here we explored this potential association in a small group of Chinese women with BN.MethodsThis retrospective study examined 34 women with BN and 34 age-matched healthy controls, all of whom underwent T1-weighted magnetic resonance imaging (MRI). Voxel-based morphometry was carried out to explore alterations in regional grey matter volume (GMV) that may be associated with BN.ResultsThe BN group showed smaller GMV in the left medial superior frontal gyrus (SFGmed.L), right superior temporal gyrus (STG.R), right median cingulate and paracingulate gyri (DCG.R), left median cingulate and paracingulate gyri (DCG.L) and left dorsolateral superior frontal gyrus (SFGdor.L). No regions showing GMV increases in BN were identified. The GMV reduction did not correlate with body mass index, duration of illness, or patients’ self-esteem or overall self-evaluation. GMV reduction correlated negatively with age in the SFGmed. L (r = − 0.516, P < 0.005), DCG. R (r = − 0.556, P < 0.005), DCG. L (r = − 0.576, P < 0.05) and SFGdor. L (r = − 0.576, P < 0.005).ConclusionsWomen with BN show reduced GMV in several brain regions, but it is difficult to know whether these changes are the result of BN pathology or of binge-eating and compensatory behavior. These changes may be associated with impaired inhibitory control, body dissatisfaction and emotion dysregulation.

Study on neuropathological mechanisms of primary monosymptomatic nocturnal enuresis in children using cerebral resting-state functional magnetic resonance imaging

Primary monosymptomatic nocturnal enuresis (PMNE) is a heterogeneous disorder, which remains a difficult condition to manage due to lack of knowledge on the underlying pathophysiological mechanisms. Here we investigated the underlying neuropathological mechanisms of PMNE with functional MRI (fMRI), combining the amplitude of low frequency fluctuation (ALFF), regional homogeneity (ReHo), and seed-based functional connectivity (seed-based FC) analyses. Compared to the control group, PMNE group showed decreased ALFF value in the left medial orbital superior frontal gyrus (Frontal_Med_Orb_L), and increased ReHo value in the left superior occipital gyrus (Occipital_Sup_L). With left thalamus as the seed, PMNE group showed significantly decreased functional connectivity to the left medial superior frontal gyrus (Frontal_Sup_Medial_L). We conclude that these abnormal brain activities are probably important neuropathological mechanisms of PMNE in children. Furthermore, this study facilitated the understanding of underlying pathogenesis of PMNE and may provide an objective basis for the effective treatment.

Disrupted brain functional hub and causal connectivity in acute mild traumatic brain injury.

There have been an increasing number of functional magnetic resonance imaging (fMRI) reports on brain abnormalities in mild traumatic brain injury (mTBI) at different phases. However, the neural bases and cognitive impairment after acute mTBI are unclear. This study aimed to identify brain functional hubs and connectivity abnormalities in acute mTBI patients and their correlations with deficits in cognitive performance. Within seven days after brain injury, mTBI patients (n=55) and age-, sex-, and educational -matched healthy controls (HCs) (n=41) underwent resting-state fMRI scans and cognitive assessments. We derived functional connectivity (FC) strength of the whole-brain network using degree centrality (DC) and performed Granger causality analysis (GCA) to analyze causal connectivity patterns in acute mTBI. Compared with HCs, acute mTBI patients had significantly decreased network centrality in the left middle frontal gyrus (MFG). Additionally, acute mTBI showed decreased inflows from the left MFG to bilateral middle temporal gyrus (MTG), left medial superior frontal gyrus (mSFG), and left anterior cingulate cortex (ACC). Correlation analyses revealed that changes in network centrality and causal connectivity were associated with deficits in cognitive performance in mTBI. Our findings may help to provide a new perspective for understanding the neuropathophysiological mechanism of acute cognitive impairment after mTBI.

Altered spontaneous brain activity in obsessive-compulsive personality disorder

BackgroundObsessive-compulsive personality disorder (OCPD) is one of the most prevalent personality disorders in general population. However, neural mechanisms underlying OCPD remain elusive. The aim of this study is to use functional magnetic resonance imaging (fMRI) to examine whether OCPD patients will exhibit altered spontaneous brain activity as compared to healthy controls (HC). MethodsResting-state fMRI data were acquired in 37 OCPD patients and 37 matched HC. Amplitudes of low-frequency fluctuation (ALFF) were calculated and compared between the two groups. Correlation analysis was performed between regional ALFF values and OCPD severity scores. ResultsSignificant group differences in regional ALFF were found in multiple brain regions. Compared to HCs, OCPD subjects had increased ALFF in bilateral caudate, left precuneus, left insula, and left medial superior frontal gyrus, and decreased ALFF in the right fusiform gyrus and left lingual gyrus. The ALFF values in the left precuneus correlated with OCPD severity scores. LimitationsWe excluded patients with comorbidity and did not conduct cognitive function assessments. Our findings are also limited to cross-sectional analysis. ConclusionsOCPD patients exhibit altered spontaneous neural activity as compared to healthy controls in multiple brain regions, which may reflect different characteristic symptoms of OCPD pathophysiology, including cognitive inflexibility, excessive self-control, lower empathy, and visual attention bias.

A functional magnetic resonance imaging study of exercise addiction

Objective: To investigate the brain activities of exercise addiction (EA) group people with the task-functional magnetic resonance image (task-fMRI). Methods: A total of 29 exercise addicts (addiction group, average age 46±4 years) and 26 non-exercise addicts (control group, average age 46±6 years) matched by sex, age, average education level and sports dependence degree were selected by using exercise addiction index (EAI) through questionnaires to members of Jiangsu Local Fitness and Long-distance Running Association between January 2018 and June 2018. The participants were scanned with fMRI while watching sports pictures or non-sports pictures. The brain responses of the two groups under two stimulation tasks were analyzed and compared. Results: Compared with the control group, while watching sports pictures, the right fusiform gyrus (MNI:x=30, y=-87, z=0), left posterior central gyrus (MNI:x=-51, y=-21, z=54), left medial superior frontal gyrus (MNI:x=-9, y=54, z=30), and right middle occipital gyrus (MNI:x=42, y=-72, z=36) were significantly inhibited in the addiction group (t-test, all P<0.05). When watching non-sports pictures, the addictive group showed the left superior frontal gyrus (MNI:x=-12, y=54, z=30), left middle frontal gyrus (MNI:x=-30, y=18, z=45), right inferior frontal gyrus (MNI:x=42, y=33, z=-12), right occipital gyrus (MNI:x=42, y=-72, z=36), and they were more significantly inhibited than the control group (t-test, all P<0.05). Conclusion: Compared to the control group, the EA group shows significant brain inhibition with visual stimulation, particularly with non-sports pictures.

Searchlight classification based on Amplitude of Low Frequency Fluctuation and functional connectivity in individuals with obsessive-compulsive symptoms

ABSTRACTIntroductionInvestigating obsessive-compulsive symptoms in subclinical populations provides a useful framework for understanding the early development of obsessive-compulsive spectrum disorders. The present study aimed to apply searchlight classification analysis on resting-state functional magnetic resonance imaging data to identify potential brain markers in subclinical individuals with obsessive-compulsive symptoms.MethodsIn this observational study, 40 college students with high obsessive-compulsive symptom scores and 40 with low obsessive-compulsive symptom scores were recruited from universities in China. We conducted searchlight classification and comparison analysis between the two groups based on Amplitude of Low Frequency Fluctuation (ALFF), fraction ALFF (fALFF) and resting-state functional connectivity using searchlight classification.ResultsWe found that the highest accuracy rate in differentiating between the two groups was 85.00%. Significant discriminating features included the ALFF of the left medial superior frontal gyrus and the functional connectivity between the right thalamus and the bilateral medial superior frontal gyrus, and the right putamen, as well as the functional connectivity between the left caudate and the right insula.ConclusionsThese findings highlight the specific and distinguishing brain functional abnormalities associated with obsessive-compulsive symptoms.

Abnormal intrinsic functional activity in patients with cervical spondylotic myelopathy: a resting-state fMRI study.

PurposeWe employed resting-state fMRI analyses to reveal central functional reorganization in the brains of patients with cervical spondylotic myelopathy (CSM) and to provide complementary evidence of cortex reorganization in these patients.Patients and methodsWe obtained Fisher’s z transformation amplitude of low-frequency fluctuations (zALFF) and Fisher’s z transformation regional homogeneity (zReHo) measurements from 33 patients with CSM and 33 healthy controls (HC) and used the brain regions with significant alterations in the zALFF or zReHo values as seed regions. Then, we calculated Pearson’s correlation coefficients between the resting-state time courses of each seed and the time series of the rest of the brain. Lastly, we computed correlations between the altered zALFF, zReHo, and functional connectivity with Japanese Orthopaedic Association scores, Neck Disability Index score, and the duration of symptoms in patients with CSM.ResultszALFF and zReHo values were increased in the left medial superior frontal gyrus (lSFGmed) and left supramarginal gyrus (lSMG) in patients with CSM compared with those in the HC group. Selecting lSFGmed as the seed, we observed increased functional connectivity between it and the left postcentral gyrus (lPoCG) and left rolandic operculum and decreased functional connectivity with the right medial superior frontal gyrus in patients with CSM. In addition, there was a significant increase in the functional connectivity between the lSMG (seed) and the left calcarine and lPoCG in patients with CSM. However, we did not find any significant correlation between the resting-state findings and the clinical performance of patients with CSM.ConclusionThese observed intrinsic functional changes in the patients with CSM may be related to functional reorganization and reflect the innate cortical plasticity in patients with CSM. Notably, the increased connectivity between the lPoCG and the two seed ROIs indicates the adaptive changes in patients with CSM. These findings provide complementary evidence of cortex reorganization in CSM.

Functional network connectivity changes in children with attention-deficit hyperactivity disorder: A resting-state fMRI study

The study aimed to investigate the pathologic mechanism of functional brain regions in attention-deficit hyperactivity disorder (ADHD) patients through making comparisons of normal and ADHD children from the perspective of the network nodes of brain network and the intensity of functional connection between bilateral of hemispheres by resting-state functional magnetic resonance imaging (fMRI). Thirty-five ADHD and forty-two children were examined by resting-state functional magnetic resonance imaging (fMRI) scans. Data analysis was done via the degree centrality (DC) and voxel-mirrored homotopic connectivity (VMHC) approaches. Compared with healthy subjects, the ADHD group exhibited significantly decreased DC values in the right posterior cingulate gyrus, left medial superior frontal gyrus, right inferior parietal gyrus, right middle frontal gyrus, left superior frontal gyrus and right superior frontal gyrus. Children with ADHD also exhibited some areas with increased DC values compared with healthy children. These regions included the cerebellar anterior lobe, right middle occipital cortex, left middle cingulate gyrus and right middle cingulate gyrus. VMHC analysis all revealed positive activation in a range of brain regions when comparing ADHD and normal children, suggesting that the VMHC scores of children with ADHD were higher in the bilateral superior frontal lobe, bilateral middle occipital lobe, and bilateral cerebellar anterior lobes. This work provides a new approach for examining the neural mechanisms underlying ADHD, demonstrating that the DC and VMHC methods enabled more comprehensive analysis that can be cross-checked.

The Relationship between Biological Motion-Based Visual Consciousness and Attention: An Electroencephalograph Study

Understanding and predicting the intentions of others through limb movements are vital to social interaction. The processing of biological motion is unique from the processing of motion of inanimate objects. Presently, there is controversy over whether visual consciousness of biological motion is regulated by visual attention. In addition, the neural mechanisms involved in biological motion-related visual awareness are not known. In the current study, the relationship between visual awareness (aware vs unaware), represented by a point-light walker and biological-motion-based attention, manipulated by a difference in congruence (congruent, incongruent) between the direction of a pre-cue and that of biological motion was explored. The neural mechanisms involved in processing the stimuli were explored through electroencephalography. Both early (50–150 ms, 100–200 ms, and 174–226 ms after target presentation) and late (350–550 ms after target presentation) awareness-related neural processings were observed during a biological motion-based congruency task. Early processing was localized to occipital–parietal regions, such as the left postcentral gyrus, the left middle occipital gyrus, and the right precentral gyrus. In the 174–226-ms window, the activity in the occipital region was gradually replaced by activity in the parietal and frontal regions. Late processing was localized to frontal–parietal regions, such as the right dorsal superior frontal gyrus, the left medial superior frontal gyrus, and the occipito-temporal regions. Congruency-related processing occurred in the 246–260-ms window and was localized to the right superior occipital gyrus. In summary, due to its complexity, biological motion awareness has a unique neural basis.

Aberrant gray matter volumes and functional connectivity in adolescent patients with ADHD.

Altered gray matter (GM) volumes and functional connectivity (FC) happens in attention-deficit/hyperactivity disorder (ADHD) patients and the intelligence quotient (IQ) of ADHD patients is generally lower than healthy subjects, while few studies have focused on the association among the three. To investigate the abnormal changes of GM volumes and FC in ADHD patients compared with typically-developing control (TD-C), as well as the association between the changes and IQ. Case control. 36 ADHD patients and 36 TD-C, aged 8-17. 3.0T/single shot echo planar imaging (EPI). Preprocessing of fMRI data and seed-based FC calculation using DPABI4.0, and VBM was performed by CAT12. Comparison between groups of smoothed GM volumes was performed using two-sample t-test within SPM 12, age and total intracranial volume (TIV) were returned as covariates. Comparison between groups of FCs was performed using a two-sample t-test within RESTplus; age was returned as a covariate. False discovery rate (FDR)-corrected and P < 0.05 was considered statistically significant. Compared with TD-C, reduced GM volumes occurred in the left superior frontal gyrus (t = -3.61, P < 0.001), right middle frontal gyrus (t = -3.97, P < 0.001), left middle cingulum (t = -3.93, P < 0.001), and left cuneus (t = -4.42, P < 0.001). Decreased FC was found between the left precuneus and left middle cingulum (t = -5.86, P < 0.001), left middle temporal gyrus, and left superior frontal gyrus (t = -5.67, P < 0.001), as well as left medial superior frontal gyrus and left superior frontal gyrus (t = -6.73, P < 0.001). The results confirmed that FCs between the regions with declined GM volumes and others were altered in ADHD patients. We speculated that abnormal changes of GM volume and FC maybe used as an imaging metric of ADHD. 2 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2020;51:719-726.

The influence of rs1360780 polymorphism of FK506-binding protein 5 gene on the brain regional homogeneity of resting state fMRI in patients with major depressive disorder

Objective To explore the influence of rs1360780 T risk allele of FK506-binding protein 5 (FKBP5) gene on the brain function under resting-state and its association with clinical symptoms as well as immune function in patients with major depressive disorder (MDD). Methods Totally 147 MDD patients and 61 gender-, age-, and education-matched healthy controls were scanned with 3.0T MRI Scanner and genotyped. The peripheral serum immunoglobulin and complement were measured. The main effect of the disease, the genotype and their interaction effects were analyzed using regional homogeneity (ReHo) by two-way ANOVA. Abnormal brain activity was identified in T risk allele carriers of rs1360780 and non-risk CC individuals in MDD using post hoc analyses. Correlation analyses were performed between ReHo values of significant brain regions and the total score, five-factor scores of Hamilton rating scale for depression (HAMD-17), serum levels of immunoglobulin and plasma complement component in MDD patients. Results (1)The results of 2×2 ANOVA showed the interaction effects located in the left opercular part of inferior frontal gyrus (MNI: x, y, z=-42, 6, 9; F=10.83), right opercular part of inferior frontal gyrus (MNI: x, y, z=30, 6, 33; F=15.05), left medial superior frontal gyrus (MNI: x, y, z=-9, 54, 0; F=9.17) and left pallidum (MNI: x, y, z=-12, 6, -6; F=11.37) (Alphasim corrected, P<0.05). (2)In post-hoc analyses for the main effect of genotype, T+ carriers with MDD showed increased ReHo values in the right opercular part of inferior frontal gyrus (MNI: x, y, z=60, 12, 6; t=2.88) compared with CC carriers; for the effect of disease-by-genotype interaction, T+ carriers with MDD showed increased ReHo values in the right opercular part of inferior frontal gyrus (MNI: x, y, z=30, 6, 33; t=2.96) and decreased ReHo values in the left orbital part of inferior frontal gyrus (MNI: x, y, z=-21, 9, -18; t=-3.21) (Alphasim corrected, P<0.05) in contrast to CC carriers.(3)Pearson's correlation showed that the average ReHo values of the right opercular part of inferior frontal gyrus negatively correlated with the content of immunoglobulin G (r=-0.528, P=0.0016, Bonferroni corrected) and positively correlated with anxiety/somatization factor score (r=0.421, P<0.001, Bonferroni corrected) in T+ carriers with MDD. Conclusion The results of this study suggest that rs1360780 T-risk allele of FKBP5 gene is involved in the changes of local neural activity in the right opercular part of inferior frontal gyrus of depressed patients and could potentially indicate a neuropathological mechanism of anxiety somatic symptoms and immune dysfunction in depression. Key words: Depression; FK506-binding protein 5; Gene-imaging; Regional homogeneity; Immune function

Neural Connectivity in Syntactic Movement Processing.

Linguistic theory suggests non-canonical sentences subvert the dominant agent-verb-theme order in English via displacement of sentence constituents to argument (NP-movement) or non-argument positions (wh-movement). Both processes have been associated with the left inferior frontal gyrus and posterior superior temporal gyrus, but differences in neural activity and connectivity between movement types have not been investigated. In the current study, functional magnetic resonance imaging data were acquired from 21 adult participants during an auditory sentence-picture verification task using passive and active sentences contrasted to isolate NP-movement, and object- and subject-cleft sentences contrasted to isolate wh-movement. Then, functional magnetic resonance imaging data from regions common to both movement types were entered into a dynamic causal modeling analysis to examine effective connectivity for wh-movement and NP-movement. Results showed greater left inferior frontal gyrus activation for Wh > NP-movement, but no activation for NP > Wh-movement. Both types of movement elicited activity in the opercular part of the left inferior frontal gyrus, left posterior superior temporal gyrus, and left medial superior frontal gyrus. The dynamic causal modeling analyses indicated that neither movement type significantly modulated the connection from the left inferior frontal gyrus to the left posterior superior temporal gyrus, nor vice-versa, suggesting no connectivity differences between wh- and NP-movement. These findings support the idea that increased complexity of wh-structures, compared to sentences with NP-movement, requires greater engagement of cognitive resources via increased neural activity in the left inferior frontal gyrus, but both movement types engage similar neural networks.

Alterations of brain network hubs in reflex syncope: Evidence from a graph theoretical analysis based on DTI.

ObjectiveWe evaluated global topology and organization of regional hubs in the brain networks and microstructural abnormalities in the white matter of patients with reflex syncope.MethodsTwenty patients with reflex syncope and thirty healthy subjects were recruited, and they underwent diffusion tensor imaging (DTI) scans. Graph theory was applied to obtain network measures based on extracted DTI data, using DSI Studio. We then investigated differences in the network measures between the patients with reflex syncope and the healthy subjects. We also analyzed microstructural abnormalities of white matter using tract‐based spatial statistics analysis (TBSS).ResultsMeasures of global topology were not different between patients with reflex syncope and healthy subjects. However, in reflex syncope patients, the strength measures of the right angular, left inferior frontal, left middle orbitofrontal, left superior medial frontal, and left middle temporal gyrus were lower than in healthy subjects. The betweenness centrality measures of the left middle orbitofrontal, left fusiform, and left lingual gyrus in patients were lower than those in healthy subjects. The PageRank centrality measures of the right angular, left middle orbitofrontal, and left superior medial frontal gyrus in patients were lower than those in healthy subjects. Regarding the analysis of the white matter microstructure, there were no differences in the fractional anisotropy and mean diffusivity values between the two groups.ConclusionsWe have identified a reorganization of network hubs in the brain network of patients with reflex syncope. These alterations in brain network may play a role in the pathophysiologic mechanism underlying reflex syncope.

Functional connectivity of suprachiasmatic nucleus in major depressive episodes patients with morning heavy night light rhythm

Objective To explore the variations of functional connectivity in depressive episode patients with diurnal rhythm. Methods Totaly 44 patients with depressive episode with diurnal rhythm(rhythm group), 58 patients with depressive episode without diurnal rhythm(non-rhythm group) and 56 matched healthy volunteer controls(healthy group)were scanned with 3.0 T MRI Scanner.Functional connectivity (FC) were calculated between suprachiasmatic nucleus(SCN) and whole brain regions.According to results of ANOVA, group-wise two sample t-test was completed.Correlation analysis were conducted between FC of significant difference brain regions and the score of Hamilton rating scale(HAMD-24) for depression. Results The brain regions showing differences among three groups were located in the left medial superior frontal gyrus(MNI: x=0, y=39, z=51; K=14) and right cerebellum crus 1(MNI: x=39, y=-48, z=-36; K=18)(P<0.05, Alphasim). Compared with non-rhythm group, the FC of rhythm group showed significantly increased in the left medial superior frontal gyrus and right triangular inferior frontal gyrus(MNI: x=39, y=27, z=27; K=10)(P<0.05, Alphasim). Compared with healthy group, the FC of non-rhythm group showed significantly decreased in left medial superior frontal gyrus(P<0.05, Alphasim). Positive correlation was found between FC in left medial superior frontal gyrus and despair score of HAMD-24(r=0.31, P=0.041). Conclusion The synergistic increase in SCN and prefrontal activity in patients with depressive episodes with morning heavy night light rhythm which may be involved in the formation mechanism of the diurnal rhythm. Key words: Depressive episode; Diurnal rhythm; Functional magnetic resonance; Suprachiasmatic nucleus; Functional connectivity

Aberrant perfusion and its connectivity within default mode network of first-episode drug-na\xefve schizophrenia patients and their unaffected first-degree relatives

Neural substrates behind schizophrenia (SZ) and its heritability mediated by brain function are largely unknown. Cerebral blood flow (CBF), as a biomarker of activation in the brain, reflects the neuronal metabolism, and is promisingly used to detect cerebral alteration thereby shedding light on the features of individuals at high genetic risk. We performed a cross-sectional functional magnetic resonance imaging (MRI) study enrolling 45 first-episode drug-naïve patients with SZ, 32 unaffected first-degree relatives of these patients, and 51 healthy controls (HCs). We examined CBF, CBF connectivity, and CBF topological properties. SZ patients showed increased CBF in the left medial superior frontal gyrus and right precuneus compared with HCs, and decreased CBF in the left middle temporal gyrus compared with their relatives. Furthermore, unaffected relatives revealed higher level of CBF pronounced in regions within default mode network (DMN). Both SZ patients and their relatives exhibited dysconnectivity patterns. Notably, as for the network properties, unaffected relatives were with an intermediate level between SZ patients and HCs in the local efficiency and global efficiency. Our findings demonstrate the aberrant CBF of areas within DMN and the CBF connectivity pattern might be a familial feature in the brain of first-episode SZ patients and their relatives.