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1.
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
2.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
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
11.
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
12.
Proc Natl Acad Sci U S A ; 121(15): e2315167121, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38557177

ABSTRACT

The default mode network (DMN) is a large-scale brain network known to be suppressed during a wide range of cognitive tasks. However, our comprehension of its role in naturalistic and unconstrained behaviors has remained elusive because most research on the DMN has been conducted within the restrictive confines of MRI scanners. Here, we use multisite GCaMP (a genetically encoded calcium indicator) fiber photometry with simultaneous videography to probe DMN function in awake, freely exploring rats. We examined neural dynamics in three core DMN nodes-the retrosplenial cortex, cingulate cortex, and prelimbic cortex-as well as the anterior insula node of the salience network, and their association with the rats' spatial exploration behaviors. We found that DMN nodes displayed a hierarchical functional organization during spatial exploration, characterized by stronger coupling with each other than with the anterior insula. Crucially, these DMN nodes encoded the kinematics of spatial exploration, including linear and angular velocity. Additionally, we identified latent brain states that encoded distinct patterns of time-varying exploration behaviors and found that higher linear velocity was associated with enhanced DMN activity, heightened synchronization among DMN nodes, and increased anticorrelation between the DMN and anterior insula. Our findings highlight the involvement of the DMN in collectively and dynamically encoding spatial exploration in a real-world setting. Our findings challenge the notion that the DMN is primarily a "task-negative" network disengaged from the external world. By illuminating the DMN's role in naturalistic behaviors, our study underscores the importance of investigating brain network function in ecologically valid contexts.


Subject(s)
Default Mode Network , Rodentia , Rats , Animals , Cerebral Cortex , Brain/diagnostic imaging , Gyrus Cinguli/diagnostic imaging , Brain Mapping , Magnetic Resonance Imaging , Nerve Net/diagnostic imaging
13.
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
14.
Soc Cogn Affect Neurosci ; 19(1)2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38451879

ABSTRACT

The concept of emotional intelligence (EI) refers to the ability to recognize and regulate emotions to appropriately guide cognition and behaviour. Unfortunately, studies on the neural bases of EI are scant, and no study so far has exhaustively investigated grey matter (GM) and white matter (WM) contributions to it. To fill this gap, we analysed trait measure of EI and structural MRI data from 128 healthy participants to shed new light on where and how EI is encoded in the brain. In addition, we explored the relationship between the neural substrates of trait EI and trait anxiety. A data fusion unsupervised machine learning approach (mCCA + jICA) was used to decompose the brain into covarying GM-WM networks and to assess their association with trait-EI. Results showed that high levels trait-EI are associated with decrease in GM-WM concentration in a network spanning from frontal to parietal and temporal regions, among which insula, cingulate, parahippocampal gyrus, cuneus and precuneus. Interestingly, we also found that the higher the GM-WM concentration in the same network, the higher the trait anxiety. These findings encouragingly highlight the neural substrates of trait EI and their relationship with anxiety. The network is discussed considering its overlaps with the Default Mode Network.


Subject(s)
Default Mode Network , Gray Matter , Humans , Gray Matter/diagnostic imaging , Brain/diagnostic imaging , Brain/physiology , Emotional Intelligence/physiology , Magnetic Resonance Imaging/methods , Anxiety/diagnostic imaging
15.
Hum Brain Mapp ; 45(5): e26657, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38544486

ABSTRACT

Although Postpartum depression (PPD) and PPD with anxiety (PPD-A) have been well characterized as functional disruptions within or between multiple brain systems, however, how to quantitatively delineate brain functional system irregularity and the molecular basis of functional abnormalities in PPD and PPD-A remains unclear. Here, brain sample entropy (SampEn), resting-state functional connectivity (RSFC), transcriptomic and neurotransmitter density data were used to investigate brain functional system irregularity, functional connectivity abnormalities and associated molecular basis for PPD and PPD-A. PPD-A exhibited higher SampEn in medial prefrontal cortex (MPFC) and posterior cingulate cortex (PPC) than healthy postnatal women (HPW) and PPD while PPD showed lower SampEn in PPC compared to HPW and PPD-A. The functional connectivity analysis with MPFC and PPC as seed areas revealed decreased functional couplings between PCC and paracentral lobule and between MPFC and angular gyrus in PPD compared to both PPD-A and HPW. Moreover, abnormal SampEn and functional connectivity were associated with estrogenic level and clinical symptoms load. Importantly, spatial association analyses between functional changes and transcriptome and neurotransmitter density maps revealed that these functional changes were primarily associated with synaptic signaling, neuron projection, neurotransmitter level regulation, amino acid metabolism, cyclic adenosine monophosphate (cAMP) signaling pathways, and neurotransmitters of 5-hydroxytryptamine (5-HT), norepinephrine, glutamate, dopamine and so on. These results reveal abnormal brain entropy and functional connectivities primarily in default mode network (DMN) and link these changes to transcriptome and neurotransmitters to establish the molecular basis for PPD and PPD-A for the first time. Our findings highlight the important role of DMN in neuropathology of PPD and PPD-A.


Subject(s)
Depression, Postpartum , Humans , Female , Depression, Postpartum/diagnostic imaging , Default Mode Network , Magnetic Resonance Imaging , Brain/diagnostic imaging , Brain Mapping , Gyrus Cinguli/diagnostic imaging , Anxiety/diagnostic imaging , Neurotransmitter Agents
16.
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
17.
Schizophr Res ; 267: 156-164, 2024 May.
Article in English | MEDLINE | ID: mdl-38547718

ABSTRACT

We characterized the neurocognitive profile of communed-based individuals and unaffected siblings of patients with psychosis from Brazil reporting psychotic experiences (PEs). We also analyzed associations between PEs and the intra and inter-functional connectivity (FC) in the Default Mode Network (DMN), the Fronto-Parietal Network (FPN) and the Salience Network (SN) measured by functional magnetic resonance imaging. The combined sample of communed-based individuals and unaffected siblings of patients with psychosis comprised 417 (neurocognition) and 85 (FC) volunteers who were divided as having low (<75th percentile) and high (≥75th percentile) PEs (positive, negative, and depressive dimensions) assessed by the Community Assessment of Psychic Experiences. The neurocognitive profile and the estimated current brief intellectual quotient (IQ) were assessed using the digit symbol (processing speed), arithmetic (working memory), block design (visual learning) and information (verbal learning) subtests of Wechsler Adult Intelligence Scale-third edition. Logistic regression models were performed for neurocognitive analysis. For neuroimaging, we used the CONN toolbox to assess FC between the specified regions, and ROI-to-ROI analysis. In the combined sample, high PEs (all dimensions) were related to lower processing speed performance. High negative PEs were related to poor visual learning performance and lower IQ, while high depressive PEs were associated with poor working memory performance. Those with high negative PEs presented FPN hypoconnectivity between the right and left lateral prefrontal cortex. There were no associations between PEs and the DMN and SN FC. Brazilian individuals with high PEs showed neurocognitive impairments like those living in wealthier countries. Hypoconnectivity in the FPN in a community sample with high PEs is coherent with the hypothesis of functional dysconnectivity in schizophrenia.


Subject(s)
Connectome , Magnetic Resonance Imaging , Psychotic Disorders , Humans , Male , Female , Adult , Psychotic Disorders/physiopathology , Psychotic Disorders/diagnostic imaging , Young Adult , Nerve Net/physiopathology , Nerve Net/diagnostic imaging , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging , Siblings , Brazil , Brain/physiopathology , Brain/diagnostic imaging , Middle Aged , Cognitive Dysfunction/physiopathology , Cognitive Dysfunction/etiology , Cognitive Dysfunction/diagnostic imaging
18.
Neuroreport ; 35(6): 380-386, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38526956

ABSTRACT

This study aims to investigate the functional connectivity (FC) changes of the habenula (Hb) among patients with major depressive disorder (MDD) after 12 weeks of duloxetine treatment (MDD12). Patients who were diagnosed with MDD for the first time and were drug-naïve were recruited at baseline as cases. Healthy controls (HCs) matched for sex, age, and education level were also recruited at the same time. At baseline, all participants underwent resting-state functional MRI. FC analyses were performed using the Hb seed region of interest, and three groups including HCs, MDD group and MDD12 group were compared using whole-brain voxel-wise comparisons. Compared to the HCs, the MDD group had decreased FC between the Hb and the right anterior cingulate cortex at baseline. Compared to the HCs, the FC between the Hb and the left medial superior frontal gyrus decreased in the MDD12 group. Additionally, the FC between the left precuneus, bilateral cuneus and Hb increased in the MDD12 group than that in the MDD group. No significant correlation was found between HDRS-17 and the FC between the Hb, bilateral cuneus, and the left precuneus in the MDD12 group. Our study suggests that the FC between the post-default mode network and Hb may be the treatment mechanism of duloxetine and the treatment mechanisms and the pathogenesis of depression may be independent of each other.


Subject(s)
Depressive Disorder, Major , Habenula , Humans , Depressive Disorder, Major/diagnostic imaging , Depressive Disorder, Major/drug therapy , Duloxetine Hydrochloride/pharmacology , Duloxetine Hydrochloride/therapeutic use , Default Mode Network , Magnetic Resonance Imaging , Rest/physiology
19.
J Cogn Neurosci ; 36(6): 1021-1036, 2024 06 01.
Article in English | MEDLINE | ID: mdl-38527069

ABSTRACT

Autobiographical memory (AM) is episodic memory for personally experienced events, in which self-representation is more important than that in laboratory-based memory. Theoretically, self-representation in a social context is categorized as the interpersonal self (IS) referred to in a social interaction with a person or the social-valued self (SS) based on the reputation of the self in the surrounding society. Although functional neuroimaging studies have demonstrated the involvement of the default mode network (DMN) in self-representation, little is known about how the DMN subsystems contribute differentially to IS-related and SS-related AMs. To elucidate this issue, we used fMRI to scan healthy young adults during the recollection of AMs. We performed multivariate pattern analysis (MVPA) and assessed functional connectivity in the DMN subsystems: the midline core, medial temporal lobe (MTL), and dorsomedial pFC (dmPFC) subsystems. The study yielded two main sets of findings. First, MVPA revealed that all DMN subsystems showed significant classification accuracy between IS-related and nonsocial-self-related AMs, and IS-related functional connectivity of the midline core regions with the retrosplenial cortex of the MTL subsystem and the dmPFC of the dmPFC subsystem was significant. Second, MVPA significantly distinguished between SS-related and nonsocial-self-related AMs in the midline core and dmPFC subsystems but not in the MTL subsystem, and SS-related functional connectivity with the midline core regions was significant in the temporal pole and TPJ of the dmPFC subsystem. Thus, dissociable neural mechanisms in the DMN could contribute to different aspects of self-representation in social AMs.


Subject(s)
Default Mode Network , Magnetic Resonance Imaging , Memory, Episodic , Humans , Default Mode Network/physiology , Default Mode Network/diagnostic imaging , Male , Young Adult , Female , Adult , Mental Recall/physiology , Self Concept , Brain Mapping , Brain/physiology , Brain/diagnostic imaging
20.
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
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