Bilateral Thalamus Research Articles

Functional connectivity differences in speech production networks in Chinese children with Rolandic epilepsy

Previous studies have demonstrated that language impairments are frequently observed in patients with benign epilepsy with centrotemporal spikes (BECTS). However, how BECTS affects language processing in the Chinese population remains unclear. With the use of functional magnetic resonance imaging (fMRI) in an overt picture-naming task, the present study examined functional connectivity in 27 children with BECTS and 26 healthy controls. The results indicated that children with BECTS showed altered functional connectivity associated with speech production between the left precuneus and the right cerebellum, between the right precuneus and the bilateral thalamus and the left superior temporal gyrus, between the right cuneus and the right postcentral gyrus and the right inferior parietal lobule, and between the right cerebellum and right middle frontal gyrus. Collectively, the findings in this study demonstrate the abnormal functional connectivity basis of speech production in Chinese children with BECTS, providing clues to understanding the brain mechanisms of language-related network in patients with BECTS.

The Cerebellum is Involved in Motor Improvements After Repetitive Transcranial Magnetic Stimulation in Parkinson's Disease Patients

Accumulating evidence indicates that repetitive transcranial magnetic stimulation (rTMS) ameliorates motor symptoms in patients with Parkinson’s disease (PD); however, patients’ responses to rTMS are different. Here, we aimed to explore neural activity changes in patients with PD exhibiting different responses to high-frequency rTMS treatments using functional magnetic resonance imaging (fMRI). We treated 24 patients with PD using 10-session rTMS (10 Hz) over the supplementary motor area (SMA) for 10 days. Resting-state functional magnetic resonance imaging (rs-fMRI), the Unified Parkinson’s Disease Rating Scale Part III (UPDRS-III) and other neuropsychological scales were performed at the baseline and endpoint of rTMS treatment. The changes in the fractional amplitude of low-frequency fluctuation (fALFF) were calculated. Significant improvements were observed in motor symptoms, especially in the sub-symptoms of bradykinesia. All the participants were subsequently stratified into responders and non-responders according to the UPDRS-III reduction. We identified increased fALFF values in the left Crus II of the cerebellar hemisphere and bilateral thalamus as responsive signs to rTMS. Furthermore, the motor response to rTMS over the SMA, measured by the reduction in UPDRS-III and bradykinesia scores, was positively associated with increased fALFF values in the left Crus2 of cerebellar hemisphere, left lobule VIIB of cerebellar hemisphere, right lobule VI of the cerebellar hemisphere, and the right postcentral gyrus. These findings provide evidence for the involvement of cerebellar activity in the motor response to rTMS treatment.

A case of Artery of Percheron infarct caused by Dengue virus encephalitis

In this communication, we describe a patient with dengue virus encephalitis who presented with fever and sudden onset bilateral oculomotor nerve involvement with left side hemi paresis, MRI showing bilateral thalamus and midbrain involvement (artery of Percheron infarct).

Structure-Function Decoupling: A Novel Perspective for Understanding the Radiation-Induced Brain Injury in Patients With Nasopharyngeal Carcinoma.

Radiation-induced functional and structural brain alterations are well documented in patients with nasopharyngeal carcinoma (NPC), followed by radiotherapy (RT); however, alterations in structure–function coupling remain largely unknown. Herein, we aimed to assess radiation-induced structure–function decoupling and its importance in predicting radiation encephalopathy (RE). We included 62 patients with NPC (22 patients in the pre-RT cohort, 18 patients in the post-RT-RE+ve cohort, and 22 patients in the post-RT-RE–ve cohort). A metric of regional homogeneity (ReHo)/voxel-based morphometry (VBM) was used to detect radiation-induced structure–function decoupling, which was then used as a feature to construct a predictive model for RE. Compared with the pre-RT group, patients in the post-RT group (which included post-RT-RE+ve and post-RT-RE–ve) showed higher ReHo/VBM coupling values in the substantia nigra (SN), the putamen, and the bilateral thalamus and lower values in the brain stem, the cerebellum, the bilateral medial temporal lobes (MTLs), the bilateral insula, the right precentral and postcentral gyri, the medial prefrontal cortex (MPFC), and the left inferior parietal lobule (IPL). In the post-RT group, negative correlations were observed between maximum dosage of RT (MDRT) to the ipsilateral temporal lobe and ReHo/VBM values in the ipsilateral middle temporal gyrus (MTG). Moreover, structure–function decoupling in the bilateral superior temporal gyrus (STG), the bilateral precentral and postcentral gyri, the paracentral lobules, the right precuneus and IPL, and the right MPFC exhibited excellent predictive performance (accuracy = 88.0%) in identifying patients likely to develop RE. These findings show that ReHo/VBM may be a novel effective imaging metric that reflects the neural mechanism underlying RE in patients with NPC.

The effect of corpus callosum abnormalities on myelin development in the fetal brain using the fast macromolecular proton fraction mapping

INTRODUCTION: There is evidence, indicate early compensatory axonal remodeling connections in the prenatal period, providing a favorable neurological outcome in isolated anomalies of the corpus callosum (CC). Mapping of the macromolecular proton fraction (MPF) is proven method of quantitative determination of myelin, which has been adapted for prenatal studies.OBJECTIVE: To investigate the relationship between CC anomalies and prenatal myelination of the brain using the fast macromolecular proton fraction (MPF) mapping.MATERIALS AND METHODS: Fetal MR imaging were performed on a 1.5 scanner (Achieva, Philips) using a 16-channel body coil. Of 66 fetal brains MRI, 12 studies were selected with MT abnormalities (22.8±2.8, 19–28.5 WG) and 21 without brain pathology (23.1±2.3, 20–29.5 WG). The images were analyzed according to structural MRI data (T2-Ssh and T1-GE, EPI, DWI, MYUR, T2-BFE-DYN) by two experienced radiologists. Fast-3D-MPF scan protocol with the MPF maps reconstruction was carried out according to a specialized protocol (open-source software: https://www.macroatomicmri.org /). Quantitative data were obtained by choosing the region of interest (ROI) in numerous brain structures bilateral (bridge, medulla oblongata, thalamus, cerebellum, and cerebral hemispheres). Statistics: distinctions between the groups and structures were assessed using repeated-measures analysis of covariance (ANCOVA), Pearson correlation analysis.RESULTS: MPF was significantly increased in the CC anomalies group as compared to controls in the medulla (3.26±0.63% vs. 2.75±0.59%, р=0.001) and cerebellum (2.02±0.55% vs. 1.76±0.34%, р=0.006). In hemispheres significant correlation with GA was observed in CC anomalies group (r=0.81, р=0.002), but was absent in controls (r=0.32, р=0.16).CONCLUSION: Primary observed MPF increase in the medulla and cerebellum as well as the dependence of the large hemispheres myelination on gestational age indicates that fetal cerebral matter undergoes early compensatory axonal remodeling in the cases of the interhemispheric connections’ reduction.

Brain structural covariation linked to screen media activity and externalizing behaviors in children.

Background and AimsScreen media activity (SMA) may impact neurodevelopment in youth. Cross-sectionally, SMA has been linked to brain structural patterns including cortical thinning in children. However, it remains unclear whether specific brain structural co-variation patterns are related to SMA and other clinically relevant measures such as psychopathology, cognition and sleep in children.MethodsAdolescent Brain Cognitive Development (ABCD) participants with useable baseline structural imaging (N = 10,691; 5,107 girls) were analyzed. We first used the Joint and Individual Variation Explained (JIVE) approach to identify cortical and subcortical covariation pattern(s) among a set of 221 brain features (i.e., surface area, thickness, or cortical and subcortical gray matter (GM) volumes). Then, the identified structural covariation pattern was used as a predictor in linear mixed-effect models to investigate its associations with SMA, psychopathology, and cognitive and sleep measures.ResultsA thalamus-prefrontal cortex (PFC)-brainstem structural co-variation pattern (circuit) was identified. The pattern suggests brainstem and bilateral thalamus proper GM volumes covary more strongly with GM volume and/or surface area in bilateral superior frontal gyral, rostral middle frontal, inferior parietal, and inferior temporal regions. This covariation pattern highly resembled one previously linked to alcohol use initiation prior to adulthood and was consistent in girls and boys. Subsequent regression analyses showed that this co-variation pattern associated with SMA (β = 0.107, P = 0.002) and externalizing psychopathology (β = 0.117, P = 0.002), respectively.Discussion and ConclusionsFindings linking SMA-related structural covariation to externalizing psychopathology in youth resonate with prior studies of alcohol-use initiation and suggest a potential neurodevelopmental mechanism underlying addiction vulnerability.

Clinical Experience in the Diagnosis and Treatment of Adult Acute Necrotizing Encephalopathy

Purpose: We report two cases diagnosed as acute necrotizing encephalopathy (ANE) with acute onset and various clinical manifestations. Methods: The patients’ data were obtained from the medical records of the Binzhou Medical University Hospital in Binzhou, China. The clinical symptoms, laboratory examination, neuroimaging, treatment, and prognosis of the 2 patients were collected and analyzed. Results: We report 2 adult ANE patients with acute onset. The first symptom was fever, followed by symptoms and signs of damage to the central nervous system. The patients were infected with herpes simplex virus and influenza virus, respectively. The main manifestation on brain magnetic resonance imaging was a mixed-signal of a “three-layer structure” in the bilateral thalamus. The first patient died. Based on the experience of the diagnosis and treatment of the first patient, combined with a review of the literature, the second patient was immediately treated with glucocorticoid pulse therapy combined with gamma globulin injection. This patient’s condition was controlled, and the prognosis was good. Conclusions: This study describes the clinical symptoms, laboratory examination, neuroimaging evidence, and treatment experience of ANE in adults. We believe that the progress of the disease may be controlled, and the prognosis may be improved if glucocorticoid pulse therapy combined with gamma globulin injection is used as soon as possible.

Enhanced Visual Cortex Activation in People With Narcolepsy Type 1 During Active Sleep Resistance: An fMRI-EEG Study.

The brain activation patterns related to sleep resistance remain to be discovered in health and disease. The maintenance of wakefulness test (MWT) is an objective neuropsychological assessment often used to assess an individual’s ability to resist sleep. It is frequently used in narcolepsy type 1, a disorder characterized by impaired sleep-wake control and the inability to resist daytime sleep. We investigated the neural correlates of active sleep resistance in 12 drug-free people with narcolepsy type 1 and 12 healthy controls. Simultaneous fMRI-EEG measurements were recorded during five cycles of two alternating conditions of active sleep resistance and waking rest. Cleaned EEG signals were used to verify wakefulness and task adherence. Pooling both subject groups, significantly higher fMRI activation when actively resisting sleep was seen in the brainstem, superior cerebellum, bilateral thalamus and visual cortices. In controls the activation clusters were generally smaller compared to patients and no significant activation was seen in the brainstem. Formal comparison between groups only found a significantly higher left primary visual cortex activation in patients during active sleep resistance. The active sleep resistance paradigm is a feasible fMRI task to study sleep resistance and induces evident arousal- and visual-related activity. Significantly higher left primary visual cortical activation in patients could be caused by an enhanced need of visual focus to resist sleep, or reflecting a more rapid descent in their level of alertness when resting.

Brain structural and functional connectivity alterations are associated with fatigue in neuromyelitis optica spectrum disorder

BackgroundMany patients with neurological disorders experience chronic fatigue, but the neural mechanisms involved are unclear.ObjectiveHere we investigated whether the brain structural and functional connectivity alterations were involved in fatigue related to neuromyelitis optica spectrum disorder (NMOSD).MethodsThis prospective pilot study used structural and resting-state functional brain magnetic resonance imaging to compare total cortical thickness, cortical surface area, deep gray matter volume and functional connectivity (FC) between 33 patients with NMOSD and 20 healthy controls (HCs). Patients were subgrouped as low fatigue (LF) and high fatigue (HF).ResultsHF patients scored higher on the Hamilton Anxiety Rating Scale and Hamilton Rating Scale for Depression than LF patients and HCs. The two patient subgroups and HC group did not differ significantly in cortical thickness, cortical surface area and volumes of the bilateral caudate nucleus, bilateral putamen, bilateral amygdala, bilateral hippocampus, bilateral thalamus proper or right nucleus accumbens (p > 0.05). However, after correcting for age, sex, years of education, anxiety and depression, HF patients showed larger left pallidum than HCs (0.1573 ± 0.0214 vs 0.1372 ± 0.0145, p = 0.009). Meanwhile, both LF patients (0.0377 ± 0.0052 vs 0.0417 ± 0.0052, p = 0.009) and HF patients (0.0361 ± 0.0071 vs 0.0417 ± 0.0052, p = 0.013) showed smaller left nucleus accumbens than HCs.. Compared with LF patients, HF patients showed significantly decreased FC between the left pallidum and bilateral cerebellar posterior lobes.ConclusionsThis was the first evidence linking structural and functional alterations in the brain to fatigue in NMOSD, and in the future, long term follow-up was necessary.

Characterizing thalamic and basal ganglia nuclei in medically intractable focal epilepsy by MR fingerprinting.

Magnetic resonance fingerprinting (MRF) is a novel, quantitative, and noninvasive technique to measure brain tissue properties. We aim to use MRF for characterizing normal-appearing thalamic and basal ganglia nuclei in the epileptic brain. A three-dimensional (3D) MRF protocol (1 mm3 isotropic resolution) was acquired from 48 patients with unilateral medically intractable focal epilepsy and 39 healthy controls (HCs). Whole-brain T1 and T2 maps (containing T1 and T2 relaxation times) were reconstructed for each subject. Ten subcortical nuclei in the thalamus and basal ganglia were segmented as regions of interest (ROIs), within which the mean T1 and T2 values, as well as their coefficient of variation (CV) were compared between the patients and HCs at the group level. Subgroup and correlation analyses were performed to examine the relationship between significant MRF measures and various clinical characteristics. Using significantly abnormal MRF measures from the group-level analyses, support vector machine (SVM) and logistic regression machine learning models were built and tested with 5-fold and 10-fold cross-validations, to separate patients from HCs, and to separate patients with left-sided and right-sided epilepsy, at the individual level. MRF revealed increased T1 mean value in the ipsilateral thalamus and nucleus accumbens; increased T1 CV in the bilateral thalamus, bilateral pallidum, and ipsilateral caudate; and increased T2 CV in the ipsilateral thalamus in patients compared to HCs (p < .05, false discovery rate [FDR] corrected). The SVM classifier produced 78.2% average accuracy to separate individual patients from HCs, with an area under the curve (AUC) of 0.83. The logistic regression classifier produced 67.4% average accuracy to separate patients with left-sided and right-sided epilepsy, with an AUC of 0.72. MRF revealed bilateral tissue-property changes in the normal-appearing thalamus and basal ganglia, with ipsilateral predominance and thalamic preference, suggesting subcortical involvement/impairment in patients with medically intractable focal epilepsy. The individual-level performance of the MRF-based machine-learning models suggests potential opportunities for predicting lateralization.

Multiple-Network Alterations in Major Depressive Disorder With Gastrointestinal Symptoms at Rest Revealed by Global Functional Connectivity Analysis

ObjectiveGastrointestinal (GI) symptoms are prominent in major depressive disorder (MDD) and bring patients lots of complaints and troubles. We aimed to explore whether there were some distinctive brain image alterations in MDD with GI symptoms, which could be used to distinguish MDD with GI symptoms from those without GI symptoms and healthy controls (HCs).MethodsA total of 35 outpatients with GI symptoms, 17 outpatients without GI symptoms, and 28 HCs were recruited. All the participants were scanned by a resting-state functional magnetic resonance imaging. Imaging data were analyzed with the global functional connectivity (GFC) and support vector machine methods.ResultsMDD with GI symptoms showed decreased GFC in the left superior medial prefrontal cortex (MPFC) compared with MDD without GI symptoms. Compared with HCs, MDD with GI symptoms showed decreased GFC in the bilateral middle temporal pole (MTP) and left posterior cingulate cortex/precuneus (PCC/Pcu), and increased GFC in the right insula and bilateral thalamus. SVM analysis showed that an accuracy was 78.85% in differentiating MDD with GI symptoms from MDD without GI symptoms by using the GFC of the left superior MPFC. A combination of GFC of the left PCC/Pcu and bilateral MTP exhibited the highest accuracy (87.30%) in differentiating patients with MDD with GI symptoms from HCs.ConclusionMDD with GI symptoms showed abnormal GFC in multiple networks, including the default mode network and cortico-limbic mood-regulating circuit. Using abnormal GFC might work well to discriminate MDD with GI symptoms from MDD without GI symptoms and HCs.

Altered Regional Homogeneity in Patients With Congenital Blindness: A Resting-State Functional Magnetic Resonance Imaging Study.

In patients with congenital blindness (CB), the lack of any visual experience may affect brain development resulting in functional, structural, or even psychological changes. Few studies to date have addressed or focused on the synchronicity of regional brain activity in patients with CB. Our study aimed to investigate regional brain activity in patients with CB in a resting state and try to explain the possible causes and effects of any anomalies. Twenty-three CB patients and 23 healthy control (HC) volunteers agreed to undergo resting state functional magnetic resonance imaging (fMRI) scans. After the fMRI data were preprocessed, regional homogeneity (ReHo) analysis was conducted to assess the differences in brain activity synchronicity between the two groups. Receiver operating characteristic (ROC) curve analysis was used to explore whether the brain areas with statistically significant ReHo differences have diagnostic and identification values for CB. All CB patients were also required to complete the Hospital Anxiety and Depression Scale (HADS) to evaluate their anxiety and depression levels. The results showed that in CB patients mean ReHo values were significantly lower than in HCs in the right orbital part of the middle frontal gyrus (MFGorb), bilateral middle occipital gyrus (MOG), and the right dorsolateral superior frontal gyrus (SFGdl), but significantly higher in the left paracentral lobule (PCL), right insula and bilateral thalamus. The ReHo value of MFGorb showed a negative linear correlation with both the anxiety score and the depression score of the HADS. ROC curve analysis revealed that the mean ReHo values which differed significantly between the groups have excellent diagnostic accuracy for CB (especially in the left PCL and right SFGdl regions). Patients with CB show abnormalities of ReHo values in several specific brain regions, suggesting potential regional structural changes, functional reorganization, or even psychological effects in these patients. FMRI ReHo analysis may find use as an objective method to confirm CB for medical or legal purposes.

Clinical features and imaging manifestations of acute necrotizing encephalopathy in children

We summarized the clinical features of acute necrotizing encephalopathy (ANE) in children. Clinical data of 14 children with ANE at one center from January 2017 to January 2020 were retrospectively analyzed. ANE severity score (ANE-ss) was used to assess ANE severity, and the Glasgow Outcome Scale-Extended was used to assess functional outcomes. Peak incidence was between 1 and 3years of age (71%), and a large percentage of males were affected (79%). The main manifestations included fever (100%), seizure (86%), and impaired consciousness (100%). Seven patients (58%) developed status epilepticus. The etiology was identified in 10 patients (71%) and mainly included H1N1 (36%) and Epstein-Barr virus (29%).Complications included multiple organ failure (MOF), predominantly liver (36%), heart (21%) and kidney (7%) failure, gastrointestinal hemorrhage (21%), hypernatremia (7%), hematuria (7%), disseminated intravascular coagulation (7%), and shock (7%). Pleocytosis was observed in two patients, and increased cerebrospinal fluid protein was found in 11 patients. A missense mutation in RANBP2 (c.1754C>T: p.Thr585Met) was observed in one patient. Magnetic resonance imaging revealed increased T2 and T1 signal density in multifocal and symmetric brain lesions (bilateral thalami, 100%) in all patients during the acute phase. There were no deaths. Nine children retained neurological sequelae affecting movement, cognition, speech, vision, and/or seizure. Four children recovered almost completely. There was a significant correlation between risk classification and outcome by ANE-ss. ANE is a group of clinical and imaging syndromes. Most patients have severe neurological sequelae, and ANE may have lower mortality. And ANE-ss can assess prognosis.

Increased Blood-Brain Barrier Permeability of the Thalamus Correlated With Symptom Severity and Brain Volume Alterations in Patients With Schizophrenia

BackgroundWhile direct in vivo data from patients is insufficient, cumulative evidence of microvascular dysfunction has shown that the blood-brain barrier (BBB) is disrupted in schizophrenia. In this study, we attempted to test the hypothesis that greater BBB permeability in patients with schizophrenia was associated with clinical characteristics and brain volumetric alterations using dynamic contrast-enhanced magnetic resonance imaging techniques. MethodsStructural magnetic resonance imaging and dynamic contrast-enhanced magnetic resonance imaging data from 29 patients with schizophrenia and 18 age- and sex-matched control subjects were obtained. We calculated the volume transfer constant (Ktrans) value and compared the difference between the 2 groups. The regions with an abnormal Ktrans value were extracted as regions of interest (thalamus), and the correlations with clinical characteristics and gray matter volume were analyzed. ResultsThe results revealed that Ktrans value of the bilateral thalamus was higher in the schizophrenia group as compared to the healthy control group (p < .001). There were significant positive correlations between thalamic mean Ktrans value with disease duration (p < .05) and symptom severity (p < .001). Analysis of the thalamic subregions revealed that BBB disruption was significant in the pulvinar, especially the medial pulvinar nucleus and lateral pulvinar nucleus (p < .001). The correlation between the Ktrans values and the corresponding volumes was negative for the whole brain, the thalamus, and the thalamic subregions. ConclusionsThese results provide the first in vivo evidence of BBB disruption of thalamus in patients with schizophrenia and suggest that BBB dysfunction might contribute to the pathological brain structural alterations in schizophrenia.

Changes of Brain Structures and Psychological Characteristics in Predatory, Affective Violent and Nonviolent Offenders.

Purpose: Violent subjects were demonstrated to exhibit abnormal brain structures; however, the brain changes may be different between criminals committing affective (VA), predatory violence (VP), and non-violence (NV). Therefore, the purpose of this study was to compare the differences in brain structures and psychological characteristics between VA, VP, and NV offenders. Methods: Twenty male criminal subjects (7 VP; 6 VA; and 7 NV) offenders; and twenty age-matched male healthy non-criminals were enrolled in this study. All subjects received psychological assessments as well as magnetic resonance imaging scans of the brain. Analysis of variance (ANOVA) was performed to understand the differences among four groups with Bonferroni correction. The voxel-based morphometry and voxel-wise diffusion tensor imaging analyses were performed to compare the gray matter (GM) volume and white matter (WM) integrity between the groups. In significant regions, a Spearman correlation analysis was performed to understand the relationship between the brain changes and psychological scores. Results: The ANOVA analysis showed that AUDIT scores were significantly different among four groups, but no significant group difference was noted after Bonferroni correction. The imaging comparisons further demonstrated that the VP and NV offenders exhibited significant alterations of WM and GM tissues in the rectus and superior temporal gyrus, respectively. In addition, the VP offenders exhibited greater GM volumes than VA offenders in the right middle frontal gyrus, and NV offenders had greater GM volumes than VP offenders in the bilateral thalamus. Conclusion: We concluded that the VA, VP, and NV groups exhibited different degrees of alterations in GM and WM tissues in regions involved in emotion and cognition.

Increased Resting-State Functional Connectivity of the Hippocampus in Rats With Sepsis-Associated Encephalopathy.

BackgroundSepsis-associated encephalopathy (SAE) has been identified as a frequent complication of sepsis, featured by an aberrant level of cognitive and affective functions. The present study is designed to explore the changes in functional connectivity (FC) of the hippocampus in rats with SAE utilizing resting-state functional magnetic resonance imaging (rs-fMRI).MethodsSprague-Dawley rats were randomly assigned to the SAE and control groups. We acquired rs-fMRI data using a 7T MRI to evaluate hippocampal network functional differences between the two groups with a seed-based approach. Behavioral performance was assessed using the open field test and forced swimming test. Statistical analysis was undertaken to evaluate the correlation between the hippocampal FC and behavioral findings.ResultsCompared with the control group, the SAE group showed increased FC between the bilateral hippocampus and thalamus, septum, bed nuclei stria terminalis (BNST), left primary forelimb somatosensory cortex (S1FL), primary motor cortex (M1), and inferior colliculus. Increased FC between the left hippocampus and thalamus, septum, BNST, left S1FL, and inferior colliculus was observed. While with the right hippocampus, FC in thalamus, septum, left S1FL and inferior colliculus was enhanced. Additionally, positive correlations were found between the hippocampal FC and the immobility time in the forced swimming test.ConclusionHippocampus-related brain networks have significant alterations in rats with SAE, and the elevated hippocampal resting-state FC was positively related to affective deficits. Changes in FC between the hippocampus and other brain regions could be a potential neuroimaging biomarker of cognitive or mental disorders triggered by SAE.

Imaging features of 10 patients with toxic encephalopathy caused by diquat

Objective: To explore the CT and MRI imaging findings of diquat toxic encephalopathy. Methods: CT and MRI imaging features of 10 patients with diquat poisoning encephalopathy who had been clinically diagnosed were retrospectively reviewed. Results: CT was performed in all 10 patients, and MRI was performed in 8 patients. In 10 patients, 7 had positive signs on CT, and 8 patients with MRI examination had abnormal changes in the images. The main CT findings were symmetrical hypodensity in bilateral cerebellar hemisphere, brainstem, thalamus and basal ganglia, and swelling of brain tissue. The main MRI findings were symmetrical lesions and brain edema in the deep nuclei of cerebellar hemisphere, brainstem, thalamus and basal ganglia, low signal on T1WI, high signal on T2WI and T2-FLAIR, and cytotoxic edema on diffusion weighted imaging (DWI) . On review after treatment, both CT and MRI showed resorption of the lesion, which narrowed in size. Conclusion: The imaging findings of diquat poisoning encephalopathy are characteristic and the location of the lesion is characteristic, and CT and MRI have a certain diagnostic value in diquat poisoning encephalopathy, which is important for clinical treatment.

Association between startle reactivity to uncertain threats and structural brain volume.

Sensitivity to uncertain threat (U-threat) is a clinically important individual difference factor in multiple psychopathologies. Recent studies have implicated a specific frontolimbic circuit as a key network involved in the anticipation of aversive stimuli. In particular, the insula, thalamus, and dorsal anterior cingulate cortex (dACC) have recently been found to be robustly activated by anticipation of U-threat. However, no study to date has examined the association between U-threat reactivity and structural brain volume. In the present study, we utilized a pooled sample of 186 young adult volunteers who completed a structural MRI scan and the well-validated No-Predictable-Unpredictable (NPU) threat of electric shock task. Startle eyeblink potentiation was collected during the NPU task as an objective index of aversive reactivity. ROI-based analyses revealed that increased startle reactivity to U-threat was associated with reduced gray matter volume in the right insula and bilateral thalamus, but not the dACC. These results add to a growing literature implicating the insula and thalamus as core nodes involved in individual differences in U-threat reactivity.

Characterising the unity and diversity of executive functions in a within-subject fMRI study

Behavioural studies investigating the relationship between Executive Functions (EFs) demonstrated evidence that different EFs are correlated with each other, but also that they are partially independent from each other. Neuroimaging studies investigating such an interrelationship with respect to the functional neuroanatomical correlates are sparse and have revealed inconsistent findings. To address this question, we created four tasks derived from the same basic paradigm, one each for updating, inhibition, switching, and dual-tasking. We assessed brain activity through functional magnetic resonance imaging (fMRI) in twenty-nine participants while they performed the four EF tasks plus control tasks. For the analysis, we first determined the neural correlates of each EF by subtracting the respective control tasks from the EF tasks. We tested for unity in EF tasks by calculating the conjunction across these four “EF-minus-control” contrasts. This identified common areas including left lateral frontal cortices [middle and superior frontal gyrus (BA 6)], medial frontal cortices (BA 8) as well as parietal cortices [inferior and superior parietal lobules (BA 39/7)]. We also observed areas activated by two or three EF tasks only, such as frontoparietal areas [e.g., SFG (BA8) right inferior parietal lobule (BA 40), left precuneus (BA 7)], and subcortical regions [bilateral thalamus (BA 50)]. Finally, we found areas uniquely activated for updating [bilateral MFG (BA 8) and left supramarginal gyrus (BA 39)], inhibition (left IFG BA 46), and dual-tasking [left postcentral gyrus (BA 40)]. These results demonstrate that the functional neuroanatomical correlates of the four investigated EFs show unity as well as diversity.

Thalamo-hippocampal dysconnectivity is associated with serum cholesterol level in drug-naïve patients with first-episode schizophrenia

Hippocampal deficits and metabolic dysregulations such as dyslipidemia have been frequently reported in schizophrenia and are suggested to contribute to the pathophysiology of schizophrenia. Hippocampus is particularly susceptible to environmental challenges including metabolism and inflammation. However, evidence linking hippocampal alterations and metabolic dysregulations are quite sparse in drug-naïve schizophrenia. A total of 166 drug-naïve patients with first-episode schizophrenia (FES) and 78 healthy controls (HC) underwent measures for several serum metabolic markers, structural and resting-state functional magnetic resonance imaging (rs-fMRI), as well as diffusion tensor imaging (DTI). Seed-to-voxel functional connectivity (FC) and probabilistic tractography were performed to assess the functional and microstructural connectivity of the bilateral hippocampi. Clinical symptoms were evaluated with Positive and Negative Syndrome Scale (PANSS). Patients with FES showed significantly decreased total cholesterol (Chol) level. Patients showed elevated FC between the left hippocampus and bilateral thalami while showing decreased microstructural connectivity between the left hippocampus and bilateral thalami. Multiple regression analyses showed that FC from the left hippocampus to the right superior frontal gyrus (SFG), bilateral frontal pole (FP), and right thalamus were negatively associated with the Chol level, while no association was observed in the HC group. Our study validated alterations in both functional and microstructural thalamo-hippocampal connectivities, and abnormal cholesterol level in FES. Moreover, decreased cholesterol level is associated with elevated thalamo-hippocampal functional connectivity in patients with FES, suggesting that dyslipidemia may interact with the hippocampal dysfunction in FES.