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1.
CNS Neurosci Ther ; 30(6): e14786, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38828694

ABSTRACT

PURPOSE: To investigate dynamic functional connectivity (dFC) within the cerebellar-whole brain network and dynamic topological properties of the cerebellar network in obstructive sleep apnea (OSA) patients. METHODS: Sixty male patients and 60 male healthy controls were included. The sliding window method examined the fluctuations in cerebellum-whole brain dFC and connection strength in OSA. Furthermore, graph theory metrics evaluated the dynamic topological properties of the cerebellar network. Additionally, hidden Markov modeling validated the robustness of the dFC. The correlations between the abovementioned measures and clinical assessments were assessed. RESULTS: Two dynamic network states were characterized. State 2 exhibited a heightened frequency, longer fractional occupancy, and greater mean dwell time in OSA. The cerebellar networks and cerebrocerebellar dFC alterations were mainly located in the default mode network, frontoparietal network, somatomotor network, right cerebellar CrusI/II, and other networks. Global properties indicated aberrant cerebellar topology in OSA. Dynamic properties were correlated with clinical indicators primarily on emotion, cognition, and sleep. CONCLUSION: Abnormal dFC in male OSA may indicate an imbalance between the integration and segregation of brain networks, concurrent with global topological alterations. Abnormal default mode network interactions with high-order and low-level cognitive networks, disrupting their coordination, may impair the regulation of cognitive, emotional, and sleep functions in OSA.


Subject(s)
Cerebellum , Nerve Net , Sleep Apnea, Obstructive , Humans , Male , Sleep Apnea, Obstructive/physiopathology , Sleep Apnea, Obstructive/diagnostic imaging , Cerebellum/diagnostic imaging , Cerebellum/physiopathology , Middle Aged , Adult , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Magnetic Resonance Imaging , Connectome , Neural Pathways/physiopathology , Neural Pathways/diagnostic imaging , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging
2.
Cereb Cortex ; 34(6)2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38836288

ABSTRACT

Major depressive disorder demonstrated sex differences in prevalence and symptoms, which were more pronounced during adolescence. Yet, research on sex-specific brain network characteristics in adolescent-onset major depressive disorder remains limited. This study investigated sex-specific and nonspecific alterations in resting-state functional connectivity of three core networks (frontoparietal network, salience network, and default mode network) and subcortical networks in adolescent-onset major depressive disorder, using seed-based resting-state functional connectivity in 50 medication-free patients with adolescent-onset major depressive disorder and 56 healthy controls. Irrespective of sex, compared with healthy controls, adolescent-onset major depressive disorder patients showed hypoconnectivity between bilateral hippocampus and right superior temporal gyrus (default mode network). More importantly, we further found that females with adolescent-onset major depressive disorder exhibited hypoconnectivity within the default mode network (medial prefrontal cortex), and between the subcortical regions (i.e. amygdala, striatum, and thalamus) with the default mode network (angular gyrus and posterior cingulate cortex) and the frontoparietal network (dorsal prefrontal cortex), while the opposite patterns of resting-state functional connectivity alterations were observed in males with adolescent-onset major depressive disorder, relative to their sex-matched healthy controls. Moreover, several sex-specific resting-state functional connectivity changes were correlated with age of onset, sleep disturbance, and anxiety in adolescent-onset major depressive disorder with different sex. These findings suggested that these sex-specific resting-state functional connectivity alterations may reflect the differences in brain development or processes related to early illness onset, underscoring the necessity for sex-tailored diagnostic and therapeutic approaches in adolescent-onset major depressive disorder.


Subject(s)
Brain , Depressive Disorder, Major , Magnetic Resonance Imaging , Nerve Net , Sex Characteristics , Humans , Depressive Disorder, Major/physiopathology , Depressive Disorder, Major/diagnostic imaging , Female , Adolescent , Male , Brain/physiopathology , Brain/diagnostic imaging , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Neural Pathways/physiopathology , Neural Pathways/diagnostic imaging , Young Adult , Age of Onset , Brain Mapping , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging
3.
Hum Brain Mapp ; 45(7): e26703, 2024 May.
Article in English | MEDLINE | ID: mdl-38716714

ABSTRACT

The default mode network (DMN) lies towards the heteromodal end of the principal gradient of intrinsic connectivity, maximally separated from the sensory-motor cortex. It supports memory-based cognition, including the capacity to retrieve conceptual and evaluative information from sensory inputs, and to generate meaningful states internally; however, the functional organisation of DMN that can support these distinct modes of retrieval remains unclear. We used fMRI to examine whether activation within subsystems of DMN differed as a function of retrieval demands, or the type of association to be retrieved, or both. In a picture association task, participants retrieved semantic associations that were either contextual or emotional in nature. Participants were asked to avoid generating episodic associations. In the generate phase, these associations were retrieved from a novel picture, while in the switch phase, participants retrieved a new association for the same image. Semantic context and emotion trials were associated with dissociable DMN subnetworks, indicating that a key dimension of DMN organisation relates to the type of association being accessed. The frontotemporal and medial temporal DMN showed a preference for emotional and semantic contextual associations, respectively. Relative to the generate phase, the switch phase recruited clusters closer to the heteromodal apex of the principal gradient-a cortical hierarchy separating unimodal and heteromodal regions. There were no differences in this effect between association types. Instead, memory switching was associated with a distinct subnetwork associated with controlled internal cognition. These findings delineate distinct patterns of DMN recruitment for different kinds of associations yet common responses across tasks that reflect retrieval demands.


Subject(s)
Default Mode Network , Emotions , Magnetic Resonance Imaging , Mental Recall , Semantics , Humans , Male , Female , Adult , Young Adult , Emotions/physiology , Default Mode Network/physiology , Default Mode Network/diagnostic imaging , Mental Recall/physiology , Cerebral Cortex/physiology , Cerebral Cortex/diagnostic imaging , Nerve Net/physiology , Nerve Net/diagnostic imaging , Brain Mapping , Pattern Recognition, Visual/physiology
4.
Sci Rep ; 14(1): 10205, 2024 05 03.
Article in English | MEDLINE | ID: mdl-38702383

ABSTRACT

Mapping the localization of the functional brain regions in trigeminal neuralgia (TN) patients is still lacking. The study aimed to explore the functional brain alterations and influencing factors in TN patients using functional brain imaging techniques. All participants underwent functional brain imaging to collect resting-state brain activity. The significant differences in regional homogeneity (ReHo) and amplitude of low frequency (ALFF) between the TN and control groups were calculated. After familywise error (FWE) correction, the differential brain regions in ReHo values between the two groups were mainly located in bilateral middle frontal gyrus, bilateral inferior cerebellum, right superior orbital frontal gyrus, right postcentral gyrus, left inferior temporal gyrus, left middle temporal gyrus, and left gyrus rectus. The differential brain regions in ALFF values between the two groups were mainly located in the left triangular inferior frontal gyrus, left supplementary motor area, right supramarginal gyrus, and right middle frontal gyrus. With the functional impairment of the central pain area, the active areas controlling memory and emotion also change during the progression of TN. There may be different central mechanisms in TN patients of different sexes, affected sides, and degrees of nerve damage. The exact central mechanisms remain to be elucidated.


Subject(s)
Magnetic Resonance Imaging , Trigeminal Neuralgia , Humans , Trigeminal Neuralgia/physiopathology , Trigeminal Neuralgia/diagnostic imaging , Male , Female , Middle Aged , Brain Mapping/methods , Brain/diagnostic imaging , Brain/physiopathology , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging , Aged , Adult
5.
Addict Biol ; 29(5): e13395, 2024 May.
Article in English | MEDLINE | ID: mdl-38709211

ABSTRACT

The brain mechanisms underlying the risk of cannabis use disorder (CUD) are poorly understood. Several studies have reported changes in functional connectivity (FC) in CUD, although none have focused on the study of time-varying patterns of FC. To fill this important gap of knowledge, 39 individuals at risk for CUD and 55 controls, stratified by their score on a self-screening questionnaire for cannabis-related problems (CUDIT-R), underwent resting-state functional magnetic resonance imaging. Dynamic functional connectivity (dFNC) was estimated using independent component analysis, sliding-time window correlations, cluster states and meta-state indices of global dynamics and were compared among groups. At-risk individuals stayed longer in a cluster state with higher within and reduced between network dFNC for the subcortical, sensory-motor, visual, cognitive-control and default-mode networks, relative to controls. More globally, at-risk individuals had a greater number of meta-states and transitions between them and a longer state span and total distance between meta-states in the state space. Our findings suggest that the risk of CUD is associated with an increased dynamic fluidity and dynamic range of FC. This may result in altered stability and engagement of the brain networks, which can ultimately translate into altered cortical and subcortical function conveying CUD risk. Identifying these changes in brain function can pave the way for early pharmacological and neurostimulation treatment of CUD, as much as they could facilitate the stratification of high-risk individuals.


Subject(s)
Brain , Connectome , Magnetic Resonance Imaging , Marijuana Abuse , Humans , Male , Female , Marijuana Abuse/physiopathology , Marijuana Abuse/diagnostic imaging , Brain/physiopathology , Brain/diagnostic imaging , Young Adult , Adult , Case-Control Studies , Nerve Net/physiopathology , Nerve Net/diagnostic imaging , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging , Adolescent
6.
Med Sci Monit ; 30: e943802, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38741355

ABSTRACT

BACKGROUND The thalamocortical tract (TCT) links nerve fibers between the thalamus and cerebral cortex, relaying motor/sensory information. The default mode network (DMN) comprises bilateral, symmetrical, isolated cortical regions of the lateral and medial parietal and temporal brain cortex. The Coma Recovery Scale-Revised (CRS-R) is a standardized neurobehavioral assessment of disorders of consciousness (DOC). In the present study, 31 patients with hypoxic-ischemic brain injury (HI-BI) were compared for changes in the TCT and DMN with consciousness levels assessed using the CRS-R. MATERIAL AND METHODS In this retrospective study, 31 consecutive patients with HI-BI (17 DOC,14 non-DOC) and 17 age- and sex-matched normal control subjects were recruited. Magnetic resonance imaging was used to diagnose HI-BI, and the CRS-R was used to evaluate consciousness levels at the time of diffusion tensor imaging (DTI). The fractional anisotropy (FA) values and tract volumes (TV) of the TCT and DMN were compared. RESULTS In patients with DOC, the FA values and TV of both the TCT and DMN were significantly lower compared to those of patients without DOC and the control subjects (p<0.05). When comparing the non-DOC and control groups, the TV of the TCT and DMN were significantly lower in the non-DOC group (p<0.05). Moreover, the CRS-R score had strong positive correlations with the TV of the TCT (r=0.501, p<0.05), FA of the DMN (r=0.532, p<0.05), and TV of the DMN (r=0.501, p<0.05) in the DOC group. CONCLUSIONS This study suggests that both the TCT and DMN exhibit strong correlations with consciousness levels in DOC patients with HI-BI.


Subject(s)
Cerebral Cortex , Coma , Consciousness , Diffusion Tensor Imaging , Hypoxia-Ischemia, Brain , Thalamus , Humans , Female , Male , Middle Aged , Thalamus/physiopathology , Thalamus/diagnostic imaging , Hypoxia-Ischemia, Brain/physiopathology , Hypoxia-Ischemia, Brain/diagnostic imaging , Adult , Consciousness/physiology , Diffusion Tensor Imaging/methods , Cerebral Cortex/physiopathology , Cerebral Cortex/diagnostic imaging , Retrospective Studies , Coma/physiopathology , Coma/diagnostic imaging , Magnetic Resonance Imaging/methods , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging , Consciousness Disorders/physiopathology , Consciousness Disorders/diagnostic imaging , Aged
7.
J Alzheimers Dis ; 99(3): 965-980, 2024.
Article in English | MEDLINE | ID: mdl-38759005

ABSTRACT

Background: Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) show differential vulnerability to large-scale brain functional networks. Plasma neurofilament light (NfL), a promising biomarker of neurodegeneration, has been linked in AD patients to glucose metabolism changes in AD-related regions. However, it is unknown whether plasma NfL would be similarly associated with disease-specific functional connectivity changes in AD and bvFTD. Objective: Our study examined the associations between plasma NfL and functional connectivity of the default mode and salience networks in patients with AD and bvFTD. Methods: Plasma NfL and neuroimaging data from patients with bvFTD (n = 16) and AD or mild cognitive impairment (n = 38; AD + MCI) were analyzed. Seed-based functional connectivity maps of key regions within the default mode and salience networks were obtained and associated with plasma NfL in these patients. RESULTS: We demonstrated divergent associations between NfL and functional connectivity in AD + MCI and bvFTD patients. Specifically, AD + MCI patients showed lower default mode network functional connectivity with higher plasma NfL, while bvFTD patients showed lower salience network functional connectivity with higher plasma NfL. Further, lower NfL-related default mode network connectivity in AD + MCI patients was associated with lower Montreal Cognitive Assessment scores and higher Clinical Dementia Rating sum-of-boxes scores, although NfL-related salience network connectivity in bvFTD patients was not associated with Neuropsychiatric Inventory Questionnaire scores. CONCLUSIONS: Our findings indicate that plasma NfL is differentially associated with brain functional connectivity changes in AD and bvFTD.


Subject(s)
Alzheimer Disease , Biomarkers , Frontotemporal Dementia , Magnetic Resonance Imaging , Neurofilament Proteins , Humans , Alzheimer Disease/blood , Alzheimer Disease/physiopathology , Alzheimer Disease/diagnostic imaging , Female , Frontotemporal Dementia/blood , Frontotemporal Dementia/physiopathology , Frontotemporal Dementia/diagnostic imaging , Male , Aged , Neurofilament Proteins/blood , Middle Aged , Biomarkers/blood , Cognitive Dysfunction/blood , Cognitive Dysfunction/physiopathology , Cognitive Dysfunction/diagnostic imaging , Brain/diagnostic imaging , Brain/physiopathology , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging
8.
Neuroimage ; 294: 120647, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38761552

ABSTRACT

Mental representation is a key concept in cognitive science; nevertheless, its neural foundations remain elusive. We employed non-invasive electrical brain stimulation and functional magnetic resonance imaging to address this. During this process, participants perceived flickering red and green visual stimuli, discerning them either as distinct, non-fused colours or as a mentally generated, fused colour (orange). The application of transcranial alternating current stimulation to the medial prefrontal region (a key node of the default-mode network) suppressed haemodynamic activation in higher-order subthalamic and central executive networks associated with the perception of fused colours. This implies that higher-order thalamocortical and default-mode networks are crucial in humans' conscious perception of mental representation.


Subject(s)
Consciousness , Magnetic Resonance Imaging , Transcranial Direct Current Stimulation , Humans , Male , Female , Adult , Transcranial Direct Current Stimulation/methods , Consciousness/physiology , Young Adult , Prefrontal Cortex/physiology , Prefrontal Cortex/diagnostic imaging , Color Perception/physiology , Brain Mapping/methods , Brain/physiology , Brain/diagnostic imaging , Default Mode Network/physiology , Default Mode Network/diagnostic imaging , Photic Stimulation/methods
9.
Behav Brain Res ; 469: 115021, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38692358

ABSTRACT

This study aims to investigate the brain networks engaged in the comprehension of indirect language, as well as the individual difference in this capacity. Specially, we aim to determine whether the difference is solely influenced by the difference in individuals' default network (DN)/language network or whether it also relies on the networks associated with processing of complex cognitive tasks, particularly the multiple demand network (MDN). Conversational indirectness scale (CIS) scores in the interpretation dimension were used as a behavioral indicator of the indirect comprehension tendency. Reading time difference between indirect replies and direct replies collected through a self-paced reading experiment was deemed as a behavioral indicator of comprehension speed of indirect replies comprehension. The two behavioral indicators were combined with resting-state functional magnetic resonance imaging (rs-fMRI). The behaviour-rfMRI analysis showed that ALFF value of right SPL and the functional connectivity (FC) between the right SPL and right IPL/SMA/ITG/Precuneus/bilateral IFG were positively correlated with the interpretation dimension of CIS scores. In addition, the ALFF value of right fusiform gyrus, the FC between the right fusiform gyrus and right precuneus, and the FCs between right SPL and right IPL/Precuneus/IFG were negatively correlated with indirect replies comprehension speed. Overlapping of these regions with large-scale brain network revealed that the right SPL was mainly located in the MDN, and the right fusiform gyrus was mainly located in the language network. Additionally, the areas showing functional connectivity with these regions were primarily located in the MDN, with a smaller subset located in the DN. Our findings suggest that the ability of individuals to actively and rapidly acquire indirect meaning relies not only on the support of the DN and the language network, but also requires collective support from the MDN.


Subject(s)
Comprehension , Individuality , Magnetic Resonance Imaging , Nerve Net , Reading , Humans , Comprehension/physiology , Male , Female , Young Adult , Adult , Nerve Net/physiology , Nerve Net/diagnostic imaging , Language , Brain Mapping , Brain/physiology , Brain/diagnostic imaging , Default Mode Network/physiology , Default Mode Network/diagnostic imaging , Connectome
10.
Hum Brain Mapp ; 45(6): e26678, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38647001

ABSTRACT

Functional gradient (FG) analysis represents an increasingly popular methodological perspective for investigating brain hierarchical organization but whether and how network hierarchy changes concomitant with functional connectivity alterations in multiple sclerosis (MS) has remained elusive. Here, we analyzed FG components to uncover possible alterations in cortical hierarchy using resting-state functional MRI (rs-fMRI) data acquired in 122 MS patients and 97 healthy control (HC) subjects. Cortical hierarchy was assessed by deriving regional FG scores from rs-fMRI connectivity matrices using a functional parcellation of the cerebral cortex. The FG analysis identified a primary (visual-to-sensorimotor) and a secondary (sensory-to-transmodal) component. Results showed a significant alteration in cortical hierarchy as indexed by regional changes in FG scores in MS patients within the sensorimotor network and a compression (i.e., a reduced standard deviation across all cortical parcels) of the sensory-transmodal gradient axis, suggesting disrupted segregation between sensory and cognitive processing. Moreover, FG scores within limbic and default mode networks were significantly correlated ( ρ = 0.30 $$ \rho =0.30 $$ , p < .005 after Bonferroni correction for both) with the symbol digit modality test (SDMT) score, a measure of information processing speed commonly used in MS neuropsychological assessments. Finally, leveraging supervised machine learning, we tested the predictive value of network-level FG features, highlighting the prominent role of the FG scores within the default mode network in the accurate prediction of SDMT scores in MS patients (average mean absolute error of 1.22 ± 0.07 points on a hold-out set of 24 patients). Our work provides a comprehensive evaluation of FG alterations in MS, shedding light on the hierarchical organization of the MS brain and suggesting that FG connectivity analysis can be regarded as a valuable approach in rs-fMRI studies across different MS populations.


Subject(s)
Cerebral Cortex , Connectome , Magnetic Resonance Imaging , Multiple Sclerosis , Nerve Net , Humans , Male , Female , Adult , Cerebral Cortex/diagnostic imaging , Cerebral Cortex/physiopathology , Middle Aged , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Connectome/methods , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis/physiopathology , Multiple Sclerosis/pathology , Default Mode Network/diagnostic imaging , Default Mode Network/physiopathology
11.
Br J Psychiatry ; 224(5): 170-178, 2024 May.
Article in English | MEDLINE | ID: mdl-38602159

ABSTRACT

BACKGROUND: Major depressive disorder (MDD) has been increasingly understood as a disruption of brain connectome. Investigating grey matter structural networks with a large sample size can provide valuable insights into the structural basis of network-level neuropathological underpinnings of MDD. AIMS: Using a multisite MRI data-set including nearly 2000 individuals, this study aimed to identify robust topology and connectivity abnormalities of grey matter structural network linked to MDD and relevant clinical phenotypes. METHOD: A total of 955 MDD patients and 1009 healthy controls were included from 23 sites. Individualised structural covariance networks (SCN) were established based on grey matter volume maps. Following data harmonisation, network topological metrics and focal connectivity were examined for group-level comparisons, individual-level classification performance and association with clinical ratings. Various validation strategies were applied to confirm the reliability of findings. RESULTS: Compared with healthy controls, MDD individuals exhibited increased global efficiency, abnormal regional centralities (i.e. thalamus, precentral gyrus, middle cingulate cortex and default mode network) and altered circuit connectivity (i.e. ventral attention network and frontoparietal network). First-episode drug-naive and recurrent patients exhibited different patterns of deficits in network topology and connectivity. In addition, the individual-level classification of topological metrics outperforms that of structural connectivity. The thalamus-insula connectivity was positively associated with the severity of depressive symptoms. CONCLUSIONS: Based on this high-powered data-set, we identified reliable patterns of impaired topology and connectivity of individualised SCN in MDD and relevant subtypes, which adds to the current understanding of neuropathology of MDD and might guide future development of diagnostic and therapeutic markers.


Subject(s)
Depressive Disorder, Major , Gray Matter , Magnetic Resonance Imaging , Humans , Depressive Disorder, Major/pathology , Depressive Disorder, Major/diagnostic imaging , Depressive Disorder, Major/physiopathology , Female , Gray Matter/diagnostic imaging , Gray Matter/pathology , Male , Adult , Middle Aged , Connectome , Nerve Net/diagnostic imaging , Nerve Net/pathology , Nerve Net/physiopathology , Case-Control Studies , Neuroimaging , Young Adult , Brain/pathology , Brain/diagnostic imaging , Default Mode Network/diagnostic imaging , Default Mode Network/pathology , Default Mode Network/physiopathology
13.
J Neurosci ; 44(20)2024 May 15.
Article in English | MEDLINE | ID: mdl-38589231

ABSTRACT

The default mode network (DMN) typically deactivates to external tasks, yet supports semantic cognition. It comprises medial temporal (MT), core, and frontotemporal (FT) subsystems, but its functional organization is unclear: the requirement for perceptual coupling versus decoupling, input modality (visual/verbal), type of information (social/spatial), and control demands all potentially affect its recruitment. We examined the effect of these factors on activation and deactivation of DMN subsystems during semantic cognition, across four task-based human functional magnetic resonance imaging (fMRI) datasets, and localized these responses in whole-brain state space defined by gradients of intrinsic connectivity. FT showed activation consistent with a central role across domains, tasks, and modalities, although it was most responsive to abstract, verbal tasks; this subsystem uniquely showed more "tuned" states characterized by increases in both activation and deactivation when semantic retrieval demands were higher. MT also activated to both perceptually coupled (scenes) and decoupled (autobiographical memory) tasks and showed stronger responses to picture associations, consistent with a role in scene construction. Core DMN consistently showed deactivation, especially to externally oriented tasks. These diverse contributions of DMN subsystems to semantic cognition were related to their location on intrinsic connectivity gradients: activation was closer to the sensory-motor cortex than deactivation, particularly for FT and MT, while activation for core DMN was distant from both visual cortex and cognitive control. These results reveal distinctive yet complementary DMN responses: MT and FT support different memory-based representations that are accessed externally and internally, while deactivation in core DMN is associated with demanding, external semantic tasks.


Subject(s)
Cognition , Default Mode Network , Magnetic Resonance Imaging , Semantics , Humans , Male , Female , Adult , Cognition/physiology , Default Mode Network/physiology , Default Mode Network/diagnostic imaging , Young Adult , Nerve Net/physiology , Nerve Net/diagnostic imaging , Brain Mapping/methods , Brain/physiology , Brain/diagnostic imaging
14.
J Psychiatr Res ; 174: 181-191, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38642455

ABSTRACT

This study aimed to explore the predictors of posttraumatic stress disorder (PTSD) in women who have recently experienced sexual assault, by examining psychological and neurophysiological factors using a prospective design with resting-state electroencephalogram (EEG) functional connectivity. The study enrolled 33 women who had been recently traumatized by sexual assault and conducted assessments within a month of the trauma. These survivors were evaluated for PTSD three months later and were classified into two groups: PTSD positive (n = 12) and PTSD negative (n = 21). They were compared to two control groups comprising women who had not experienced any extremely traumatic events: 25 with depression and 25 healthy controls. The evaluation focused on resting-state EEG functional connectivity within default mode network (DMN) using small-worldness (SW), based on graph theory. We also assessed self-reported levels of depression, anxiety, anger, and executive functions. The findings indicated that survivors who developed PTSD three months post-trauma exhibited higher anxiety levels and reduced DMN SW in the beta 3 frequency, compared to those who did not develop PTSD. Contrary to expectations, survivors without PTSD showed decreased executive functioning and lower prefrontal centrality compared to those with PTSD. This study underscores the importance of early assessment and intervention for sexual assault survivors at risk of developing PTSD.


Subject(s)
Default Mode Network , Electroencephalography , Sex Offenses , Stress Disorders, Post-Traumatic , Humans , Stress Disorders, Post-Traumatic/physiopathology , Stress Disorders, Post-Traumatic/diagnostic imaging , Female , Adult , Prospective Studies , Young Adult , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging
15.
Int J Neural Syst ; 34(7): 2450031, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38623649

ABSTRACT

Schizophrenia is accompanied by aberrant interactions of intrinsic brain networks. However, the modulatory effect of electroencephalography (EEG) rhythms on the functional connectivity (FC) in schizophrenia remains unclear. This study aims to provide new insight into network communication in schizophrenia by integrating FC and EEG rhythm information. After collecting simultaneous resting-state EEG-functional magnetic resonance imaging data, the effect of rhythm modulations on FC was explored using what we term "dynamic rhythm information." We also investigated the synergistic relationships among three networks under rhythm modulation conditions, where this relationship presents the coupling between two brain networks with other networks as the center by the rhythm modulation. This study found FC between the thalamus and cortical network regions was rhythm-specific. Further, the effects of the thalamus on the default mode network (DMN) and salience network (SN) were less similar under alpha rhythm modulation in schizophrenia patients than in controls ([Formula: see text]). However, the similarity between the effects of the central executive network (CEN) on the DMN and SN under gamma modulation was greater ([Formula: see text]), and the degree of coupling was negatively correlated with the duration of disease ([Formula: see text], [Formula: see text]). Moreover, schizophrenia patients exhibited less coupling with the thalamus as the center and greater coupling with the CEN as the center. These results indicate that modulations in dynamic rhythms might contribute to the disordered functional interactions seen in schizophrenia.


Subject(s)
Cerebral Cortex , Electroencephalography , Magnetic Resonance Imaging , Nerve Net , Schizophrenia , Thalamus , Humans , Schizophrenia/physiopathology , Schizophrenia/diagnostic imaging , Thalamus/physiopathology , Thalamus/diagnostic imaging , Cerebral Cortex/physiopathology , Cerebral Cortex/diagnostic imaging , Adult , Male , Female , Nerve Net/physiopathology , Nerve Net/diagnostic imaging , Brain Waves/physiology , Young Adult , Neural Pathways/physiopathology , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging , Connectome
16.
Brain Lang ; 252: 105405, 2024 May.
Article in English | MEDLINE | ID: mdl-38579461

ABSTRACT

This review examines whether and how the "default mode" network (DMN) contributes to semantic processing. We review evidence implicating the DMN in the processing of individual word meanings and in sentence- and discourse-level semantics. Next, we argue that the areas comprising the DMN contribute to semantic processing by coordinating and integrating the simultaneous activity of local neuronal ensembles across multiple unimodal and multimodal cortical regions, creating a transient, global neuronal ensemble. The resulting ensemble implements an integrated simulation of phenomenological experience - that is, an embodied situation model - constructed from various modalities of experiential memory traces. These situation models, we argue, are necessary not only for semantic processing but also for aspects of cognition that are not traditionally considered semantic. Although many aspects of this proposal remain provisional, we believe it provides new insights into the relationships between semantic and non-semantic cognition and into the functions of the DMN.


Subject(s)
Cognition , Semantics , Humans , Cognition/physiology , Default Mode Network/physiology , Default Mode Network/diagnostic imaging , Brain/physiology
17.
Neuroimage Clin ; 42: 103610, 2024.
Article in English | MEDLINE | ID: mdl-38677099

ABSTRACT

Parkinson's disease (PD) is a neurodegenerative disease with cognitive as well as motor impairments. While much is known about the brain networks leading to motor impairments in PD, less is known about the brain networks contributing to cognitive impairments. Here, we leveraged resting-state functional magnetic resonance imaging (rs-fMRI) data from the Parkinson's Progression Marker Initiative (PPMI) to examine network dysfunction in PD patients with cognitive impairment. We focus on canonical cortical networks linked to cognition, including the salience network (SAL), frontoparietal network (FPN), and default mode network (DMN), as well as a subcortical basal ganglia network (BGN). We used the Montreal Cognitive Assessment (MoCA) as a continuous index of coarse cognitive function in PD. In 82 PD patients, we found that lower MoCA scores were linked with lower intra-network connectivity of the FPN. We also found that lower MoCA scores were linked with lower inter-network connectivity between the SAL and the BGN, the SAL and the DMN, as well as the FPN and the DMN. These data elucidate the relationship of cortical and subcortical functional connectivity with cognitive impairments in PD.


Subject(s)
Cognitive Dysfunction , Magnetic Resonance Imaging , Nerve Net , Parkinson Disease , Humans , Parkinson Disease/physiopathology , Parkinson Disease/diagnostic imaging , Parkinson Disease/complications , Male , Female , Cognitive Dysfunction/physiopathology , Cognitive Dysfunction/etiology , Cognitive Dysfunction/diagnostic imaging , Aged , Magnetic Resonance Imaging/methods , Middle Aged , Nerve Net/physiopathology , Nerve Net/diagnostic imaging , Cerebral Cortex/physiopathology , Cerebral Cortex/diagnostic imaging , Connectome/methods , Brain/physiopathology , Brain/diagnostic imaging , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging
18.
Asian J Psychiatr ; 95: 104025, 2024 May.
Article in English | MEDLINE | ID: mdl-38522164

ABSTRACT

This study aimed to investigate the neurobiological mechanisms by which microRNA 124 (miR-124) is involved in major depressive disorder (MDD). We enrolled 53 untreated MDD patients and 38 healthy control (HC) subjects who completed behavior assessments and resting-state functional MRI (rs-fMRI) scans. MiR-124 expression levels were detected in the peripheral blood of all participants. We determined that miR-124 levels could influence depressive symptoms via disrupted large-scale intrinsic intra- and internetwork connectivity, including the default mode network (DMN)-DMN, dorsal attention network (DAN)-salience network (SN), and DAN-cingulo-opercular network (CON). This study deepens our understanding of how miR-124 dysregulation contributes to depression.


Subject(s)
Depressive Disorder, Major , Magnetic Resonance Imaging , MicroRNAs , Humans , Depressive Disorder, Major/physiopathology , Depressive Disorder, Major/diagnostic imaging , Adult , MicroRNAs/genetics , Male , Female , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Connectome , Middle Aged , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging , Young Adult , Brain/diagnostic imaging , Brain/physiopathology
19.
Psychiatry Clin Neurosci ; 78(5): 291-299, 2024 May.
Article in English | MEDLINE | ID: mdl-38444215

ABSTRACT

AIM: The effective connectivity between the striatum and cerebral cortex has not been fully investigated in attention-deficit/hyperactivity disorder (ADHD). Our objective was to explore the interaction effects between diagnosis and age on disrupted corticostriatal effective connectivity and to represent the modulation function of altered connectivity pathways in children and adolescents with ADHD. METHODS: We performed Granger causality analysis on 300 participants from a publicly available Attention-Deficit/Hyperactivity Disorder-200 dataset. By computing the correlation coefficients between causal connections between striatal subregions and other cortical regions, we estimated the striatal inflow and outflow connection to represent intermodulation mechanisms in corticostriatal pathways. RESULTS: Interactions between diagnosis and age were detected in the superior occipital gyrus within the visual network, medial prefrontal cortex, posterior cingulate gyrus, and inferior parietal lobule within the default mode network, which is positively correlated with hyperactivity/impulsivity severity in ADHD. Main effect of diagnosis exhibited a general higher cortico-striatal causal connectivity involving default mode network, frontoparietal network and somatomotor network in ADHD compared with comparisons. Results from high-order effective connectivity exhibited a disrupted information pathway involving the default mode-striatum-somatomotor-striatum-frontoparietal networks in ADHD. CONCLUSION: The interactions detected in the visual-striatum-default mode networks pathway appears to be related to the potential distraction caused by long-term abnormal information input from the retina in ADHD. Higher causal connectivity and weakened intermodulation may indicate the pathophysiological process that distractions lead to the impairment of motion planning function and the inhibition/control of this unplanned motion signals in ADHD.


Subject(s)
Attention Deficit Disorder with Hyperactivity , Cerebral Cortex , Corpus Striatum , Magnetic Resonance Imaging , Humans , Attention Deficit Disorder with Hyperactivity/physiopathology , Attention Deficit Disorder with Hyperactivity/diagnostic imaging , Child , Adolescent , Male , Female , Cerebral Cortex/physiopathology , Cerebral Cortex/diagnostic imaging , Corpus Striatum/physiopathology , Corpus Striatum/diagnostic imaging , Nerve Net/physiopathology , Nerve Net/diagnostic imaging , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging , Connectome , Neural Pathways/physiopathology , Neural Pathways/diagnostic imaging
20.
Eur Neuropsychopharmacol ; 82: 72-81, 2024 May.
Article in English | MEDLINE | ID: mdl-38503084

ABSTRACT

Mindfulness-based cognitive therapy (MBCT) stands out as a promising augmentation psychological therapy for patients with obsessive-compulsive disorder (OCD). To identify potential predictive and response biomarkers, this study examines the relationship between clinical domains and resting-state network connectivity in OCD patients undergoing a 3-month MBCT programme. Twelve OCD patients underwent two resting-state functional magnetic resonance imaging sessions at baseline and after the MBCT programme. We assessed four clinical domains: positive affect, negative affect, anxiety sensitivity, and rumination. Independent component analysis characterised resting-state networks (RSNs), and multiple regression analyses evaluated brain-clinical associations. At baseline, distinct network connectivity patterns were found for each clinical domain: parietal-subcortical, lateral prefrontal, medial prefrontal, and frontal-occipital. Predictive and response biomarkers revealed significant brain-clinical associations within two main RSNs: the ventral default mode network (vDMN) and the frontostriatal network (FSN). Key brain nodes -the precuneus and the frontopolar cortex- were identified within these networks. MBCT may modulate vDMN and FSN connectivity in OCD patients, possibly reducing symptoms across clinical domains. Each clinical domain had a unique baseline brain connectivity pattern, suggesting potential symptom-based biomarkers. Using these RSNs as predictors could enable personalised treatments and the identification of patients who would benefit most from MBCT.


Subject(s)
Magnetic Resonance Imaging , Mindfulness , Obsessive-Compulsive Disorder , Humans , Obsessive-Compulsive Disorder/therapy , Obsessive-Compulsive Disorder/diagnostic imaging , Obsessive-Compulsive Disorder/physiopathology , Male , Female , Adult , Mindfulness/methods , Rest/physiology , Brain/diagnostic imaging , Brain/physiopathology , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Young Adult , Middle Aged , Cognitive Behavioral Therapy/methods , Default Mode Network/diagnostic imaging , Default Mode Network/physiopathology , Treatment Outcome , Neural Pathways/physiopathology , Neural Pathways/diagnostic imaging
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