New resting-state fMRI related studies at PubMed

Disrupted interhemispheric coordination of sensory-motor networks and insula in major depressive disorder

Fri, 03/24/2023 - 10:00

Front Neurosci. 2023 Mar 7;17:1135337. doi: 10.3389/fnins.2023.1135337. eCollection 2023.


OBJECTIVE: Prior researches have identified distinct differences in neuroimaging characteristics between healthy controls (HCs) and patients with major depressive disorder (MDD). However, the correlations between homotopic connectivity and clinical characteristics in patients with MDD have yet to be fully understood. The present study aimed to investigate common and unique patterns of homotopic connectivity and their relationships with clinical characteristics in patients with MDD.

METHODS: We recruited 42 patients diagnosed with MDD and 42 HCs. We collected a range of clinical variables, as well as exploratory eye movement (EEM), event-related potentials (ERPs) and resting-state functional magnetic resonance imaging (rs-fMRI) data. The data were analyzed using correlation analysis, support vector machine (SVM), and voxel-mirrored homotopic connectivity (VMHC).

RESULTS: Compared with HCs, patients with MDD showed decreased VMHC in the insula, and increased VMHC in the cerebellum 8/vermis 8/vermis 9 and superior/middle occipital gyrus. SVM analysis using VMHC values in the cerebellum 8/vermis 8/vermis 9 and insula, or VMHC values in the superior/middle occipital gyrus and insula as inputs can distinguish HCs and patients with MDD with high accuracy, sensitivity, and specificity.

CONCLUSION: The study demonstrated that decreased VMHC in the insula and increased VMHC values in the sensory-motor networks may be a distinctive neurobiological feature for patients with MDD, which could potentially serve as imaging markers to discriminate HCs and patients with MDD.

PMID:36960171 | PMC:PMC10028102 | DOI:10.3389/fnins.2023.1135337

The maternal brain is more flexible and responsive at rest: effective connectivity of the parental caregiving network in postpartum mothers

Fri, 03/24/2023 - 10:00

Sci Rep. 2023 Mar 23;13(1):4719. doi: 10.1038/s41598-023-31696-4.


The field of neuroscience has largely overlooked the impact of motherhood on brain function outside the context of responses to infant stimuli. Here, we apply spectral dynamic causal modelling (spDCM) to resting-state fMRI data to investigate differences in brain function between a group of 40 first-time mothers at 1-year postpartum and 39 age- and education-matched women who have never been pregnant. Using spDCM, we investigate the directionality (top-down vs. bottom-up) and valence (inhibition vs excitation) of functional connections between six key left hemisphere brain regions implicated in motherhood: the dorsomedial prefrontal cortex, ventromedial prefrontal cortex, posterior cingulate cortex, parahippocampal gyrus, amygdala, and nucleus accumbens. We show a selective modulation of inhibitory pathways related to differences between (1) mothers and non-mothers, (2) the interactions between group and cognitive performance and (3) group and social cognition, and (4) differences related to maternal caregiving behaviour. Across analyses, we show consistent disinhibition between cognitive and affective regions suggesting more efficient, flexible, and responsive behaviour, subserving cognitive performance, social cognition, and maternal caregiving. Together our results support the interpretation of these key regions as constituting a parental caregiving network. The nucleus accumbens and the parahippocampal gyrus emerging as 'hub' regions of this network, highlighting the global importance of the affective limbic network for maternal caregiving, social cognition, and cognitive performance in the postpartum period.

PMID:36959247 | DOI:10.1038/s41598-023-31696-4

Daily artificial gravity is associated with greater neural efficiency during sensorimotor adaptation

Thu, 03/23/2023 - 10:00

Cereb Cortex. 2023 Mar 23:bhad094. doi: 10.1093/cercor/bhad094. Online ahead of print.


Altered vestibular signaling and body unloading in microgravity results in sensory reweighting and adaptation. Microgravity effects are well-replicated in head-down tilt bed rest (HDBR). Artificial gravity (AG) is a potential countermeasure to mitigate the effects of microgravity on human physiology and performance. We examined the effectiveness of daily AG for mitigating brain and/or behavioral changes in 60 days of HDBR. One group received AG for 30 minutes daily (AG; n = 16) and a control group spent the same time in HDBR but received no AG (CTRL; n = 8). All participants performed a sensorimotor adaptation task five times during fMRI scanning: twice prior to HDBR, twice during HDBR, and once following HDBR. The AG group showed similar behavioral adaptation effects compared with the CTRLs. We identified decreased brain activation in the AG group from pre to late HDBR in the cerebellum for the task baseline portion and in the thalamus, calcarine, cuneus, premotor cortices, and superior frontal gyrus in the AG group during the early adaptation phase. The two groups also exhibited differential brain-behavior correlations. Together, these results suggest that AG may result in a reduced recruitment of brain activity for basic motor processes and sensorimotor adaptation. These effects may stem from the somatosensory and vestibular stimulation that occur with AG.

PMID:36958815 | DOI:10.1093/cercor/bhad094

Predicting Future Depressive Episodes from Resting-State fMRI with Generative Embedding

Thu, 03/23/2023 - 10:00

Neuroimage. 2023 Mar 21:119986. doi: 10.1016/j.neuroimage.2023.119986. Online ahead of print.


After a first episode of major depressive disorder (MDD), there is substantial risk for a long-term remitting-relapsing course. Prevention and early interventions are thus critically important. Various studies have examined the feasibility of detecting at-risk individuals based on out-of-sample predictions about the future occurrence of depression. However, functional magnetic resonance imaging (MRI) has received very little attention for this purpose so far. Here, we explored the utility of generative models (i.e. different dynamic causal models, DCMs) as well as functional connectivity (FC) for predicting future episodes of depression in never-depressed adults, using a large dataset (N=906) of task-free ("resting state") fMRI data from the UK Biobank. Connectivity analyses were conducted using timeseries from pre-computed spatially independent components of different dimensionalities. Over a three year period, 50% of participants showed indications of at least one depressive episode, while the other 50% did not. Using nested cross-validation for training and a held-out test set (80/20 split), we systematically examined the combination of 8 connectivity feature sets and 17 classifiers. We found that a generative embedding procedure based on combining regression DCM (rDCM) with a support vector machine (SVM) enabled the best predictions, both on the training set (0.63 accuracy, 0.66 area under the curve, AUC) and the test set (0.62 accuracy, 0.64 AUC; p<0.001). However, on the test set, rDCM was only slightly superior to predictions based on FC (0.59 accuracy, 0.61 AUC). Interpreting model predictions based on SHAP (SHapley Additive exPlanations) values suggested that the most predictive connections were widely distributed and not confined to specific networks. Overall, our analyses suggest (i) ways of improving future fMRI-based generative embedding approaches for the early detection of individuals at-risk for depression and that (ii) achieving accuracies of clinical utility may require combination of fMRI with other data modalities.

PMID:36958617 | DOI:10.1016/j.neuroimage.2023.119986

Common and exclusive spontaneous neural activity patterns underlying pure generalized anxiety disorder and comorbid generalized anxiety disorder and depression

Thu, 03/23/2023 - 10:00

J Affect Disord. 2023 Mar 21:S0165-0327(23)00387-7. doi: 10.1016/j.jad.2023.03.047. Online ahead of print.


BACKGROUND: This study aimed to identify common and exclusive neural substrates underlying pure generalized anxiety disorder (GAD, G0) and comorbid GAD and depression (G1), assess whether they could assist in diagnosis and prediction of treatment response, and determine whether comorbid depression in GAD patients would change their neural plasticity.

METHODS: A longitudinal study was conducted, involving 98 patients (40 in the G0 group and 58 in the G1 group) and 54 healthy controls (HCs). The fractional amplitude of low-frequency fluctuations (fALFF), support vector machine, and support vector regression were employed.

RESULTS: The shared neural underpinnings across the two subtypes of GAD were hyperactivity in the right cerebellar Crus II and inferior temporal gyrus and hypoactivity in the right postcentral gyrus. The G1 group showed hypoactivity in the frontal gyrus, compared with HCs, and hyperactivity in the middle temporal gyrus, compared with the G0 group or HCs. These alterations could aid in diagnosis and the prediction of treatment response with high accuracy. After treatment, both the G1 and G0 groups showed higher fALFF than those before treatment but were located in different brain regions.

LIMITATIONS: The study was performed in a single center and subjects showed a fairly homogeneous ethnicity.

CONCLUSIONS: Common and exclusive neural substrates underlying the two subtypes of GAD were identified, which could assist in diagnosis and the prediction of treatment response. Pharmacotherapy for the two subtypes of GAD recruited different pathways, suggesting that comorbid depression in GAD patients would change their neural plasticity.

PMID:36958484 | DOI:10.1016/j.jad.2023.03.047

The inferior frontal gyrus spontaneous activity mediates the association of early life adversity with self-control ability in late adolescents

Thu, 03/23/2023 - 10:00

Psychophysiology. 2023 Mar 23:e14291. doi: 10.1111/psyp.14291. Online ahead of print.


Self-control, the ability to regulate prepotent desires or impulses in order to realize one's valued goal, has been found to be associated with early life adversity. However, the neural correlates underlying this relationship remain poorly understood. The present study employed resting-state functional magnetic resonance imaging (fMRI) to investigate this issue among late adolescents (N = 538). Results showed that family unpredictability rather than family harshness of early life adversity was negatively correlated with self-control ability. The whole brain analysis showed that self-control was associated with enhanced ALFF in the right middle and inferior frontal gyrus, the left anterior insula, and with decreased ALFF in the left precuneus. Moreover, the mediating analysis showed that ALFF in the inferior frontal gyrus could partially mediated the association of family unpredictability with self-control ability. These findings suggested that the brain regions implicating in executive control might be the neural correlates underlying the relationship between early life adversity and self-control ability, which advances the mechanistic understanding of how early family environment relates to the development of self-regulation in late adolescence.

PMID:36951595 | DOI:10.1111/psyp.14291

Aberrant modular segregation of brain networks in female patients with bulimia nervosa

Thu, 03/23/2023 - 10:00

Int J Eat Disord. 2023 Mar 23. doi: 10.1002/eat.23939. Online ahead of print.


OBJECTIVE: Bulimia nervosa (BN) is an eating disorder associated with the dysfunction of intrinsic brain networks. However, whether the network disruptions in BN patients manifest as dysconnectivity or imbalances of network modular segregation remains unclear.

METHOD: We collected data from 41 women with BN and 41 matched healthy control (HC) women. We performed graph theory analysis based on resting-state functional magnetic resonance imaging (RS-fMRI) data; then, we computed the participation coefficient (PC) among brain modules to characterize the modular segregation for the BN and HC groups. The number of intra- and inter-modular connections was calculated to explain the PC changes. Additionally, we examined the potential associations of the measures mentioned above with clinical variables within the BN group.

RESULTS: Compared with the HC group, the BN group showed significantly decreased PC in the fronto-parietal network (FPN), cingulo-opercular network (CON), and cerebellum (Cere). Additionally, the number of intra-modular connections of the default mode network (DMN) and the number of the inter-modular connections between the DMN and CON, FPN and Cere, and CON and Cere in the BN group were lower than those in the HC group. The nodal level analysis showed that the BN group had a decreased PC of the anterior prefrontal cortex (aPFC), dorsal frontal cortex (dFC), inferior parietal lobule (IPL), thalamus, and angular gyrus. Further, these metrics were significantly correlated with clinical variables in the BN group.

DISCUSSION: These findings may provide novel insights to capture atypical topologies associated with pathophysiology mechanisms and clinical symptoms underlying BN.

PMID:36951235 | DOI:10.1002/eat.23939

Altered functional connectivity associated with striatal dopamine depletion in Parkinson's disease

Thu, 03/23/2023 - 10:00

Cereb Cortex Commun. 2023 Feb 20;4(1):tgad004. doi: 10.1093/texcom/tgad004. eCollection 2023.


We aimed to clarify whether dopamine depletion in the posterior dorsal striatum in early-stage Parkinson's disease (PD) alters synchronized activity in the cortico-basal ganglia motor circuit. In sum, 14 PD patients and 16 matched healthy controls (HC) underwent [11C]-2-β-carbomethoxy-3-β-(4-fluorophenyl) tropane positron emission tomography to identify striatal dopamine-depleted areas. The identified map was applied to functional magnetic resonance imaging (fMRI) to discover abnormalities in functional connectivity (FC) during motor-task and rest-state in PD patients in the drug-off state relative to HC. Striatal dopamine-depleted areas formed synchronized fMRI activity that largely corresponded to the cortico-basal ganglia motor circuit. Group comparisons revealed that striatal dopamine-depleted areas exhibited decreased FC with the medial premotor cortex during motor-task and with the medial, lateral premotor and primary motor cortices during rest-state. Striatal dopamine-depleted areas also elucidated decreased FC in the subthalamic nucleus (STN) in PD both during motor-task and rest-state. The STN regions that exhibited reduced FC with striatal dopamine-depleted areas demonstrated excessive FC with the lateral premotor and primary motor cortices in PD only during rest-state. Our findings suggest that striatal dopamine-depleted area reduced synchronized activity with the motor cortices and STN, which, in turn, induces an abnormal increase in coupling between the areas in PD.

PMID:36949935 | PMC:PMC10026073 | DOI:10.1093/texcom/tgad004

IMOVE: Protocol for a randomized, controlled 2x2 factorial trial of improvisational movement and social engagement interventions in older adults with early Alzheimer's disease

Thu, 03/23/2023 - 10:00

Contemp Clin Trials Commun. 2023 Jan 24;32:101073. doi: 10.1016/j.conctc.2023.101073. eCollection 2023 Apr.


BACKGROUND: In addition to cognitive impairment, people with Alzheimer's disease (PWAD) experience neuropsychiatric symptoms (e.g., apathy, depression), altered gait, and poor balance that further diminish their quality of life (QoL). Here, we describe a unique, randomized, controlled trial to test the hypothesis that both movement and social engagement aspects of a group dance intervention alter the connectivity of key brain networks involved in motor and social-emotional functioning and lead to improved QoL in PWAD.

METHODS: IMOVE (NCT03333837) was a single-center, randomized, controlled 2x2 factorial trial that assigned PWAD/caregiver dyads to one of 4 study conditions (Movement Group, Movement Alone, Social Group, or Usual Care control). The Movement Group participated in twice-weekly group improvisational dance (IMPROVment® Method) classes for 12 weeks. The Movement Alone intervention captured the same dance movement and auditory stimuli as the group class without social interaction, and the Social Group used improvisational party games to recapitulate the fun and playfulness of the Movement Group without the movement. The primary outcome was change in QoL among PWAD. Key secondary outcomes were functional brain network measures assessed using graph-theory analysis of resting-state functional magnetic resonance imaging scans, as well as neuropsychiatric symptoms, gait, and balance.

RESULTS: A total of 111 dyads were randomized; 89 completed the study, despite interruption and modification of the protocol due to COVID-19 restrictions (see companion paper by Fanning et al.). The data are being analyzed and will be submitted for publication in 2023.

PMID:36949846 | PMC:PMC10025420 | DOI:10.1016/j.conctc.2023.101073

Altered topological properties of functional brain networks in patients with first episode, late-life depression before and after antidepressant treatment

Thu, 03/23/2023 - 10:00

Front Aging Neurosci. 2023 Mar 6;15:1107320. doi: 10.3389/fnagi.2023.1107320. eCollection 2023.


OBJECTIVES: To preliminarily explore the functional activity and information integration of the brains under resting state based on graph theory in patients with first-episode, late-life depression (LLD) before and after antidepressant treatment.

METHODS: A total of 50 patients with first-episode LLD and 40 non-depressed controls (NCs) were recruited for the present research. Participants underwent the RBANS test, the 17-item Hamilton depression rating scale (HAMD-17) test, and resting-state functional MRI scans (rs-fMRI). The RBANS test consists of 12 sub-tests that contribute to a total score and index scores across the five domains: immediate memory, visuospatial/constructional, language, attention, and delayed memory. Escitalopram or sertraline was adopted for treating depression, and the dosage of the drug was adjusted by the experienced psychiatrists. Of the 50 LLD patients, 27 cases who completed 6-month follow-ups and 27 NCs matched with age, sex, and education level were included for the final statistical analysis.

RESULTS: There were significant differences in RBANS total score, immediate memory, visuospatial/constructional, language, attention, and delayed memory between LLD baseline group and NCs group (P < 0.05). Considering the global attribute indicators, the clustering coefficient of global indicators was lower in the LLD baseline group than in the NCs group, and the small-world attribute of functional brain networks existed in all three groups. The degree centrality and node efficiency of some brains were lower in the LLD baseline group than in the NCs group. After 6 months of antidepressant therapy, the scores of HAMD-17, immediate memory, language, and delayed memory in the LLD follow-up group were higher than those in the LLD baseline group. Compared with the LLD baseline group, the degree centrality and node efficiency of some brains in the cognitive control network were decreased in the LLD follow-up group.

CONCLUSIONS: The ability to integrate and divide labor of functional brain networks declines in LLD patients and linked with the depression severity. After the relief of depressive symptoms, the small-world attribute of functional brain networks in LLD patients persists. However, the information transmission efficiency and centrality of some brain regions continue to decline over time, perhaps related to their progressive cognitive impairment.

PMID:36949772 | PMC:PMC10025486 | DOI:10.3389/fnagi.2023.1107320

Frequency-Specific Alterations of Spontaneous Brain Activity in First-Episode Drug-Naïve Schizophrenia

Thu, 03/23/2023 - 10:00

Sichuan Da Xue Xue Bao Yi Xue Ban. 2023 Mar;54(2):281-286. doi: 10.12182/20230360103.


OBJECTIVE: To investigate frequency-specific alterations of spontaneous brain activity in first-episode drug-naïve schizophrenia (SZ) patients and the associations with clinical symptoms.

METHODS: We collected the resting-state functional MRI (rs-fMRI) data from 84 first-episode drug-naïve SZ patients and 94 healthy controls (HCs) and calculated the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) of four frequency bands, including slow-2, slow-3, slow-4, and slow-5. Two-sample t-tests were used to evaluate the intergroup differences in ALFF and ReHo, while partial correlation analyses were conducted to explore the associations between abnormal ALFF and ReHo and the severity of clinical symptoms in the SZ group.

RESULTS: Compared with HCs, the SZ group showed reduced ALFF in superior cerebellum and cerebellar vermis across slow-2, slow-3, and slow-4 bands, while increased ALFF was found in left superior temporal gyrus, middle temporal gyrus, and superior temporal pole at slow-4 band. Moreover, reduced ReHo was observed in the right precentral and postcentral gyri at slow-3 band in the SZ group. Additionally, the ALFF of left superior temporal gyrus, middle temporal gyrus, and superior temporal pole in slow-4 band showed a trend of positive correlation with the excited factor score of Positive and Negative Syndrome Scale (PANSS) in the SZ group.

CONCLUSION: Our results suggest that local alterations of spontaneous brain activity were frequency-specific in first-episode drug-naïve SZ patients.

PMID:36949686 | DOI:10.12182/20230360103

Abnormal characteristic static and dynamic functional network connectivity in idiopathic normal pressure hydrocephalus

Thu, 03/23/2023 - 10:00

CNS Neurosci Ther. 2023 Mar 22. doi: 10.1111/cns.14178. Online ahead of print.


AIMS: Idiopathic Normal pressure hydrocephalus (iNPH) is a neurodegenerative disease characterized by gait disturbance, dementia, and urinary dysfunction. The neural network mechanisms underlying this phenomenon is currently unknown.

METHODS: To investigate the resting-state functional connectivity (rs-FC) abnormalities of iNPH-related brain connectivity from static and dynamic perspectives and the correlation of these abnormalities with clinical symptoms before and 3-month after shunt. We investigated both static and dynamic functional network connectivity (sFNC and dFNC, respectively) in 33 iNPH patients and 23 healthy controls (HCs).

RESULTS: The sFNC and dFNC of networks were generally decreased in iNPH patients. The reduction in sFNC within the default mode network (DMN) and between the somatomotor network (SMN) and visual network (VN) were related to symptoms. The temporal properties of dFNC and its temporal variability in state-4 were sensitive to the identification of iNPH and were correlated with symptoms. The temporal variability in the dorsal attention network (DAN) increased, and the average instantaneous FC was altered among networks in iNPH. These features were partially associated with clinical symptoms.

CONCLUSION: The dFNC may be a more sensitive biomarker for altered network function in iNPH, providing us with extra information on the mechanisms of iNPH.

PMID:36949617 | DOI:10.1111/cns.14178

Aberrant intra- and internetwork functional connectivity patterns of the anterior and posterior hippocampal networks in schizophrenia

Thu, 03/23/2023 - 10:00

CNS Neurosci Ther. 2023 Mar 22. doi: 10.1111/cns.14171. Online ahead of print.


AIM: Schizophrenia is associated with abnormal hippocampal structure and function. Available evidence suggests that the anterior and posterior hippocampus are differentially affected by schizophrenia pathology. This study was designed to provide new insight into the anterior and posterior hippocampus in schizophrenia from the perspective of functional connectivity.

METHODS: Based on resting-state functional magnetic resonance imaging data of 71 schizophrenia patients and 74 normal controls, we utilized a data-driven approach to functionally segment the hippocampus into anterior and posterior segments and then investigated the functional connectivity patterns within and between the two hippocampal networks at the network, edge, and nodal levels.

RESULTS: We found that schizophrenia patients showed hyperconnectivity of both the anterior and posterior hippocampal networks. We also observed that the network alterations appear somewhat greater in the anterior hippocampal network than the posterior network, the left side than the right, and the intranetwork connectivity than the internetwork connectivity.

CONCLUSION: The results reveal convergent and divergent intranetwork and internetwork connectivity patterns of the anterior and posterior hippocampus in schizophrenia, providing novel and important insights into the mechanisms of hippocampal pathology in schizophrenia.

PMID:36949599 | DOI:10.1111/cns.14171

PTSD and comorbid MDD is associated with activation of the right frontoparietal network

Wed, 03/22/2023 - 10:00

Psychiatry Res Neuroimaging. 2023 Mar 17;331:111630. doi: 10.1016/j.pscychresns.2023.111630. Online ahead of print.


There is growing evidence of abnormalities in intrinsic functional connectivity (FC) in posttraumatic stress disorder (PTSD) and major depressive disorder (MDD). However, there has been less work on the commonly occurring co-presentation of PTSD and MDD. Characterising intrinsic FC abnormalities in this clinical population is important for understanding how they may contribute towards impairments underpinned by different networks. Participants were mothers enroled in the Drakenstein Child Health Study from Western Cape, South Africa. Mothers between 18 and 50 years of age were recruited and divided into 4 groups: PTSD, MDD, PTSD with MDD, and healthy controls. Participants underwent resting-state fMRI at the 18-month postpartum time point. Functional connectivity within and between higher order cognitive control networks, including the salience, dorsal attention, frontoparietal, and default mode networks were compared across the 4 groups. PTSD with comorbid MDD was associated with greater intrinsic FC within the R FPAR, relative to controls and the mono-diagnostic groups. Intrinsic FC differences were observed within the default mode network for the MDD group. No group differences in connectivity between networks were observed. Differential intrinsic connectivity in participants with comorbidity are consistent with evidence that such individuals have more severe illness and require more robust intervention.

PMID:36947943 | DOI:10.1016/j.pscychresns.2023.111630

Active Inference, Epistemic Value, and Uncertainty in Conceptual Disorganization in First-Episode Schizophrenia

Wed, 03/22/2023 - 10:00

Schizophr Bull. 2023 Mar 22;49(Supplement_2):S115-S124. doi: 10.1093/schbul/sbac125.


BACKGROUND AND HYPOTHESIS: Active inference has become an influential concept in psychopathology. We apply active inference to investigate conceptual disorganization in first-episode schizophrenia. We conceptualize speech production as a decision-making process affected by the latent "conceptual organization"-as a special case of uncertainty about the causes of sensory information. Uncertainty is both minimized via speech production-in which function words index conceptual organization in terms of analytic thinking-and tracked by a domain-general salience network. We hypothesize that analytic thinking depends on conceptual organization. Therefore, conceptual disorganization in schizophrenia would be both indexed by low conceptual organization and reflected in the effective connectivity within the salience network.

STUDY DESIGN: With 1-minute speech samples from a picture description task and resting state fMRI from 30 patients and 30 healthy subjects, we employed dynamic causal and probabilistic graphical models to investigate if the effective connectivity of the salience network underwrites conceptual organization.

STUDY RESULTS: Low analytic thinking scores index low conceptual organization which affects diagnostic status. The influence of the anterior insula on the anterior cingulate cortex and the self-inhibition within the anterior cingulate cortex are elevated given low conceptual organization (ie, conceptual disorganization).

CONCLUSIONS: Conceptual organization, a construct that explains formal thought disorder, can be modeled in an active inference framework and studied in relation to putative neural substrates of disrupted language in schizophrenia. This provides a critical advance to move away from rating-scale scores to deeper constructs in the pursuit of the pathophysiology of formal thought disorder.

PMID:36946528 | DOI:10.1093/schbul/sbac125

Neural Correlates of Formal Thought Disorder Dimensions in Psychosis

Wed, 03/22/2023 - 10:00

Schizophr Bull. 2023 Mar 22;49(Supplement_2):S104-S114. doi: 10.1093/schbul/sbac120.


BACKGROUND AND HYPOTHESIS: Formal thought disorder (FTD) is a core symptom of psychosis, but its neural correlates remain poorly understood. This study tested whether four FTD dimensions differ in their association with brain perfusion and brain structure.

STUDY DESIGN: This cross-sectional study investigated 110 patients with schizophrenia spectrum disorders using 3T magnetic resonance imaging (MRI). The Thought and Language Disorder scale (TALD) was utilized, which comprises four subscales: Objective Positive (OP), Objective Negative (ON), Subjective Positive (SP), and Subjective Negative (SN). Resting-state cerebral blood flow (rsCBF), cortical thickness (CortTh), gray matter volume (GMV), and diffusion MRI tractography were tested for associations with TALD subscales controlling for age, medication, total intracranial volume, and for variance of the 3 other TALD subscales.

STUDY RESULTS: Following Bonferroni correction, the FTD dimensions presented distinct neural correlates. OP scores were associated with increased rsCBF and increased GMV in the right cerebellum lingual gyrus. Higher SP scores were linked to increased GMV in bilateral prefrontal cortex. In contrast, ON was associated with increased GMV in the right premotor cortex. At more liberal statistical thresholds, higher SP was associated with increased CortTh in the right inferior frontal gyrus, whereas SN scores were linked to decreased GMV in the right prefrontal lobe, the left inferior temporal gyrus, and the left supplementary motor area. Unadjusted analyses mostly corroborated these findings.

CONCLUSION: These findings stress the heterogeneity in FTD, suggesting distinct neural patterns for specific FTD experiences. In sum, FTD in psychosis may require distinct treatment strategies and further mechanistic investigations on single-item levels.

PMID:36946525 | DOI:10.1093/schbul/sbac120

Abnormally Increased Effective Connectivity of the Periaqueductal Gray in Migraine Without Aura Patients

Tue, 03/21/2023 - 10:00

Clin J Pain. 2023 Apr 1;39(4):175-179. doi: 10.1097/AJP.0000000000001099.


OBJECTIVES: The periaqueductal gray (PAG) is a key region in the descending pain modulatory system. We applied a Granger causality analysis-based approach to examine resting-state effective connectivity of the bilateral PAG regions in migraine patients without aura (MwoA).

MATERIALS AND METHODS: Resting-state functional magnetic resonance imaging data were obtained from 28 MwoA patients and 17 healthy controls. The effective connectivity of the bilateral PAG was characterized using a voxel-wised Granger causality analysis method. The resulting effective connectivity measurements were assessed for correlations with other clinical features.

RESULTS: Compared with the healthy controls, MwoA patients showed increased effective connectivity from the left PAG to the left anterior cingulate gyrus and right postcentral gyrus. Meanwhile, MwoA patients also showed increased effective connectivity from the right PAG to the left precentral gyrus and increased effective connectivity from the left caudate and right middle occipital gyrus to the right PAG.

DISCUSSION: Abnormally increased effective connectivity between PAG and limbic system, primary sensorimotor cortex, and visual cortex may play a key role in neuropathological features, perception, and affection of MwoA. The current study provides further insights into the complex scenario of MwoA mechanisms.

PMID:36943161 | DOI:10.1097/AJP.0000000000001099

Creative thinking and brain network development in schoolchildren

Tue, 03/21/2023 - 10:00

Dev Sci. 2023 Mar 21:e13389. doi: 10.1111/desc.13389. Online ahead of print.


Fostering creative minds has always been a premise to ensure adaptation to new challenges of human civilization. While some alternative educational settings (i.e., Montessori) were shown to nurture creative skills, it is unknown how they impact underlying brain mechanisms across the school years. This study assessed creative thinking and resting-state functional connectivity via fMRI in 75 children (4-18 y.o.) enrolled either in Montessori or traditional schools. We found that pedagogy significantly influenced creative performance and underlying brain networks. Replicating past work, Montessori-schooled children showed higher scores on creative thinking tests. Using static functional connectivity analysis, we found that Montessori-schooled children showed decreased within-network functional connectivity of the salience network. Moreover, using dynamic functional connectivity, we found that traditionally-schooled children spent more time in a brain state characterized by high intra-default mode network connectivity. These findings suggest that pedagogy may influence brain networks relevant to creative thinking-particularly the default and salience networks. Further research is needed, like a longitudinal study, to verify these results given the implications for educational practitioners. RESEARCH HIGHLIGHTS: Most executive jobs are prospected to be obsolete within several decades, so creative skills are seen as essential for the near future. School experience has been shown to play a role in creativity development, however, the underlying brain mechanisms remained under-investigated yet. Seventy-five 4-18 years-old children, from Montessori or traditional schools, performed a creativity task at the behavioral level, and a 6-min resting-state MR scan. We uniquely report preliminary evidence for the impact of pedagogy on functional brain networks.

PMID:36942648 | DOI:10.1111/desc.13389

Functional and structural alterations of dorsal attention network in preclinical and early-stage Alzheimer's disease

Tue, 03/21/2023 - 10:00

CNS Neurosci Ther. 2023 Mar 21. doi: 10.1111/cns.14092. Online ahead of print.


OBJECTIVES: Subjective cognitive decline (SCD) and amnestic mild cognitive impairment (aMCI) are known as the preclinical and early stage of Alzheimer's disease (AD). The dorsal attention network (DAN) is mainly responsible for the "top-down" attention process. However, previous studies mainly focused on single functional modality and limited structure. This study aimed to investigate the multimodal alterations of DAN in SCD and aMCI to assess their diagnostic value in preclinical and early-stage AD.

METHODS: Resting-state functional magnetic resonance imaging (MRI) was carried out to measure the fractional amplitude of low-frequency fluctuation (fALFF), regional homogeneity (ReHo), and functional connectivity (FC). Structural MRI was used to calculate the gray matter volume (GMV) and cortical thickness. Moreover, receiver-operating characteristic (ROC) analysis was used to distinguish these alterations in SCD and aMCI.

RESULTS: The SCD and aMCI groups showed both decreased ReHo in the right middle temporal gyrus (MTG) and decreased GMV compared to healthy controls (HCs). Especially in the SCD group, there were increased fALFF and increased ReHo in the left inferior occipital gyrus (IOG), decreased fALFF and increased FC in the left inferior parietal lobule (IPL), and reduced cortical thickness in the right inferior temporal gyrus (ITG). Furthermore, functional and structural alterations in the SCD and aMCI groups were closely related to episodic memory (EM), executive function (EF), and information processing speed (IPS). The combination of multiple indicators of DAN had a high accuracy in differentiating clinical stages.

CONCLUSIONS: Our current study demonstrated functional and structural alterations of DAN in SCD and aMCI, especially in the MTG, IPL, and SPL. Furthermore, cognitive performance was closely related to these significant alterations. Our study further suggested that the combined multiple indicators of DAN could be acted as the latent neuroimaging markers of preclinical and early-stage AD for their high diagnostic value.

PMID:36942514 | DOI:10.1111/cns.14092

Altered functional connectivity of the default mode and frontal control networks in patients with insomnia

Tue, 03/21/2023 - 10:00

CNS Neurosci Ther. 2023 Mar 21. doi: 10.1111/cns.14183. Online ahead of print.


AIMS: The purpose of this study was to investigate the association between spontaneous regional activity and brain functional connectivity, which maybe can distinguish insomnia while being responsive to repetitive transcranial magnetic stimulation (rTMS) treatment effects in insomnia patients.

METHODS: Using resting-state functional magnetic resonance imaging data from 38 chronic insomnia patients and 36 healthy volunteers, we compared the amplitude of low-frequency fluctuations (ALFF) between the two groups. Of all the patients with insomnia, 20 received rTMS for 4 weeks, while 18 patients received a 4-week pseudo-stimulation intervention. Seed-based resting-state functional connectivity (RSFC) analysis was conducted from regions with significantly different ALFF values, and the association between RSFC value and Pittsburgh Sleep Quality Index score was determined.

RESULTS: Our results revealed that insomnia patients presented a significantly higher ALFF value in the posterior cingulate cortex (PCC), whereas a significantly lower ALFF value was observed in the superior parietal lobule (SPL). Moreover, significantly reduced RSFC was detected from both PCC to prefrontal cortex connections, as well as from left SPL to frontal pole connections. In addition, RSFC from frontal pole to left SPL negatively predicted sleep quality (PSQI) and treatment response in patients' group.

CONCLUSION: Our findings suggest that disrupted frontoparietal network connectivity may be a biomarker for insomnia in middle-aged adults, reinforcing the potential of rTMS targeting the frontal lobes. Monitoring pretreatment RSFC could offer greater insight into how rTMS treatments are responded to by insomniacs.

PMID:36942498 | DOI:10.1111/cns.14183