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Human lateral Frontal Pole contributes to control over emotional approach-avoidance actions.

Mon, 02/10/2020 - 02:27
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Human lateral Frontal Pole contributes to control over emotional approach-avoidance actions.

J Neurosci. 2020 Feb 06;:

Authors: Bramson B, Folloni D, Verhagen L, Hartogsveld B, Mars RB, Toni I, Roelofs K

Abstract
Regulation of emotional behavior is essential for human social interactions. Recent work has exposed its cognitive complexity, as well as its unexpected reliance on portions of the anterior prefrontal cortex (aPFC) also involved in exploration, relational reasoning, and counterfactual choice, rather than on dorsolateral and medial prefrontal areas involved in several forms of cognitive control. This study anatomically qualifies the contribution of aPFC territories to the regulation of prepotent approach-avoidance action-tendencies elicited by emotional faces, and explores a possible structural pathway through which this emotional action regulation might be implemented.We provide converging evidence from task-based fMRI, diffusion-weighted imaging, and functional connectivity fingerprints for a novel neural element in emotional regulation. Task-based fMRI in human male participants (N = 40) performing an emotional approach-avoidance task identified aPFC territories involved in the regulation of action-tendencies elicited by emotional faces. Connectivity fingerprints, based on diffusion-weighted imaging and resting-state connectivity, localized those task-defined frontal regions to the lateral frontal pole (FPl), an anatomically-defined portion of the aPFC that lacks a homologous counterpart in macaque brains. Probabilistic tractography indicated that 10-20% of inter-individual variation in emotional regulation abilities is accounted for by the strength of structural connectivity between FPl and amygdala. Evidence from an independent replication sample (N = 50; 10 females) further substantiated this result. These findings provide novel neuroanatomical evidence for incorporating FPl in models of control over human action-tendencies elicited by emotional faces.Significance statementSuccessful regulation of emotional behaviors is a prerequisite for successful participation in human society, as is evidenced by the social isolation and loss of occupational opportunities often encountered by people suffering from emotion-regulation disorders such as social-anxiety disorder and psychopathy. Knowledge about the precise cortical regions and connections supporting this control is crucial for understanding both the nature of computations needed to successfully traverse the space of possible actions in social situations, and the potential interventions that might result in efficient treatment of social-emotional disorders. This study provides evidence for a precise cortical region (FPl) and a structural pathway (the ventral amygdalofugal bundle) through which a cognitively complex form of emotional action regulation might be implemented in the human brain.

PMID: 32034069 [PubMed - as supplied by publisher]

Preliminary Report on the Effects of a Low Dose of LSD on Resting-State Amygdala Functional Connectivity.

Mon, 02/10/2020 - 02:27
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Preliminary Report on the Effects of a Low Dose of LSD on Resting-State Amygdala Functional Connectivity.

Biol Psychiatry Cogn Neurosci Neuroimaging. 2019 Dec 20;:

Authors: Bershad AK, Preller KH, Lee R, Keedy S, Wren-Jarvis J, Bremmer MP, de Wit H

Abstract
BACKGROUND: The practice of "microdosing," or the use of repeated, very low doses of lysergic acid diethylamide (LSD) to improve mood or cognition, has received considerable public attention, but empirical studies are lacking. Controlled studies are needed to investigate both the therapeutic potential and the neurobiological underpinnings of this pharmacologic treatment.
METHODS: The present study was designed to examine the effects of a single low dose of LSD (13 μg) versus placebo on resting-state functional connectivity and cerebral blood flow in healthy young adults. Twenty men and women, 18 to 35 years old, participated in 2 functional magnetic resonance imaging scanning sessions in which they received placebo or LSD under double-blind conditions. During each session, the participants completed drug effect and mood questionnaires, and physiological measures were recorded. During expected peak drug effect, they underwent resting-state blood oxygen level-dependent and arterial spin labeling scans. Cerebral blood flow as well as amygdala and thalamic connectivity were analyzed.
RESULTS: LSD increased amygdala seed-based connectivity with the right angular gyrus, right middle frontal gyrus, and the cerebellum, and decreased amygdala connectivity with the left and right postcentral gyrus and the superior temporal gyrus. This low dose of LSD had weak and variable effects on mood, but its effects on positive mood were positively correlated with the increase in amygdala-middle frontal gyrus connectivity strength.
CONCLUSIONS: These preliminary findings show that a very low dose of LSD, which produces negligible subjective changes, alters brain connectivity in limbic circuits. Additional studies, especially with repeated dosing, will reveal whether these neural changes are related to the drug's purported antidepressant effect.

PMID: 32033922 [PubMed - as supplied by publisher]

Resting state fMRI based multilayer network configuration in patients with schizophrenia.

Sat, 02/08/2020 - 23:25
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Resting state fMRI based multilayer network configuration in patients with schizophrenia.

Neuroimage Clin. 2020 Jan 11;25:102169

Authors: Gifford G, Crossley N, Kempton MJ, Morgan S, Dazzan P, Young J, McGuire P

Abstract
Novel methods for measuring large-scale dynamic brain organisation are needed to provide new biomarkers of schizophrenia. Using a method for modelling dynamic modular organisation (Mucha et al., 2010), evidence suggests higher 'flexibility' (switching between multilayer network communities) to be a feature of schizophrenia (Braun et al., 2016). The current study compared flexibility between 55 patients with schizophrenia and 72 controls (the COBRE Dataset). In addition, novel methods of 'between resting state network synchronisation' (BRSNS) and the probability of transition from one community to another were used to further describe group differences in dynamic community structure. There was significantly higher schizophrenia group flexibility scores in cerebellar (F (1124) = 9.33, p (FDR) = 0.017), subcortical (F (1124) = 13.14, p (FDR) = 0.005), and fronto-parietal task control (F (1124) = 7.19, p (FDR) = 0.033) resting state networks (RSNs), as well as in the left thalamus (MNI XYZ: -2, -13, 12; F(1, 124) = 17.1, p (FDR) < 0.001) and the right crus I (MNI XYZ: 35, -67, -34; F (1, 124) = 19.65, p (FDR) < 0.001). Flexibility in the left thalamus reflected transitions between communities covering default mode and sensory-somatomotor RSNs. BRSNS scores suggested altered dynamic inter-RSN modular configuration in schizophrenia. This study suggests less stable community structure in a schizophrenia group at an RSN and node level and provides novel methods of exploring dynamic community structure. Mediation of group differences by mean time window correlation did however suggest flexibility to be no better as a schizophrenia biomarker than simpler measures and a range of methodological choices affected results.

PMID: 32032819 [PubMed - as supplied by publisher]

Functional Dissociations of the Left Anterior and Posterior Occipitotemporal Cortex for Semantic and Non-semantic Phonological Access.

Sat, 02/08/2020 - 23:25
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Functional Dissociations of the Left Anterior and Posterior Occipitotemporal Cortex for Semantic and Non-semantic Phonological Access.

Neuroscience. 2020 Feb 04;:

Authors: Dong J, Lu C, Chen C, Li H, Liu X, Mei L

Abstract
Previous studies have identified the ventral and dorsal brain regions that respectively support semantic and non-semantic phonological access. Nevertheless, the specific role of the left occipitotemporal cortex (lOTC) in the two pathways of phonological access is ambiguous. To address that question, the present study compared word reading in Chinese (presumably relying on the semantic pathway) with that in English (presumably relying on the non-semantic pathway). Results revealed a clear dissociation in the involvement of the anterior and posterior lOTC in semantic and non-semantic phonological access. Specifically, the anterior lOTC showed greater activation for Chinese than for English, whereas the posterior lOTC showed greater activation for English than for Chinese. More importantly, both psychophysiological interaction analysis and resting-state functional connectivity analysis showed that the anterior lOTC was functionally connected to the ventral brain regions (e.g., left anterior fusiform gyrus, anterior temporal lobe, and ventral inferior frontal gyrus), whereas the posterior lOTC was functionally connected to the dorsal brain regions (e.g., left posterior superior temporal gyrus, supramarginal gyrus, and dorsal inferior frontal gyrus). These results suggest that the anterior and posterior lOTC are involved in semantic and non-semantic phonological access, respectively.

PMID: 32032670 [PubMed - as supplied by publisher]

Intrinsic brain activity of subcortical-cortical sensorimotor system and psychomotor alterations in schizophrenia and bipolar disorder: A preliminary study.

Sat, 02/08/2020 - 23:25
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Intrinsic brain activity of subcortical-cortical sensorimotor system and psychomotor alterations in schizophrenia and bipolar disorder: A preliminary study.

Schizophr Res. 2020 Feb 03;:

Authors: Magioncalda P, Martino M, Conio B, Lee HC, Ku HL, Chen CJ, Inglese M, Amore M, Lane TJ, Northoff G

Abstract
OBJECTIVE: Alterations in psychomotor dimension cut across different psychiatric disorders, such as schizophrenia (SCZ) and bipolar disorder (BD). This preliminary study aimed to investigate the organization of intrinsic brain activity in the subcortical-cortical sensorimotor system in SCZ (and BD) as characterized according to psychomotor dimension.
METHOD: In this resting-state functional magnetic resonance imaging (fMRI) study, functional connectivity (FC) between thalamus and sensorimotor network (SMN), along with FC from substantia nigra (SN) and raphe nuclei (RN) to basal ganglia (BG) and thalamic regions, were investigated by using an a-priori-driven and dimensional approach. This was done in two datasets: SCZ patients showing inhibited psychomotricity (n = 18) vs. controls (n = 19); SCZ patients showing excited psychomotricity (n = 20) vs. controls (n = 108). Data from a third dataset of BD in inhibited depressive or manic phases (reflecting inhibited or excited psychomotricity) were used as control.
RESULTS: SCZ patients suffering from psychomotor inhibition showed decreased thalamus-SMN FC toward around-zero values paralleled by a concomitant reduction of SN-BG/thalamus FC and RN-BG/thalamus FC (as BD patients in inhibited depression). By contrast, SCZ patients suffering from psychomotor excitation exhibited increased thalamus-SMN FC toward positive values paralleled by a concomitant reduction of RN-BG/thalamus FC (as BD patients in mania).
CONCLUSIONS: These findings suggest that patients exhibiting low or high levels of psychomotor activity show distinct patterns of thalamus-SMN coupling, which could be traced to specific deficit in SN- or RN-related connectivity. Notably, this was independent from the diagnosis of SCZ or BD, supporting an RDoC-like dimensional approach to psychomotricity.

PMID: 32029353 [PubMed - as supplied by publisher]

Resting-state Functional Connectivity of the Right Temporoparietal Junction Relates to Belief Updating and Reorienting during Spatial Attention.

Sat, 02/08/2020 - 02:24
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Resting-state Functional Connectivity of the Right Temporoparietal Junction Relates to Belief Updating and Reorienting during Spatial Attention.

J Cogn Neurosci. 2020 Feb 06;:1-13

Authors: Käsbauer AS, Mengotti P, Fink GR, Vossel S

Abstract
Whereas multiple studies characterized the resting-state functional connectivity (rsFC) of the right temporoparietal junction (rTPJ), little is known about the link between rTPJ rsFC and cognitive functions. Given a putative involvement of rTPJ in both reorienting of attention and the updating of probabilistic beliefs, this study characterized the relationship between rsFC of rTPJ with dorsal and ventral attention systems and these two cognitive processes. Twenty-three healthy young participants performed a modified location-cueing paradigm with true and false prior information about the percentage of cue validity to assess belief updating and attentional reorienting. Resting-state fMRI was recorded before and after the task. Seed-based correlation analysis was employed, and correlations of each behavioral parameter with rsFC before the task, as well as with changes in rsFC after the task, were assessed in an ROI-based approach. Weaker rsFC between rTPJ and right intraparietal sulcus before the task was associated with relatively faster updating of the belief that the cue will be valid after false prior information. Moreover, relatively faster belief updating, as well as faster reorienting, were related to an increase in the interhemispheric rsFC between rTPJ and left TPJ after the task. These findings are in line with task-based connectivity studies on related attentional functions and extend results from stroke patients demonstrating the importance of interhemispheric parietal interactions for behavioral performance. The present results not only highlight the essential role of parietal rsFC for attentional functions but also suggest that cognitive processing during a task changes connectivity patterns in a performance-dependent manner.

PMID: 32027583 [PubMed - as supplied by publisher]

Large-scale dynamic causal modeling of major depressive disorder based on resting-state functional magnetic resonance imaging.

Sat, 02/08/2020 - 02:24
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Large-scale dynamic causal modeling of major depressive disorder based on resting-state functional magnetic resonance imaging.

Hum Brain Mapp. 2020 Mar;41(4):865-881

Authors: Li G, Liu Y, Zheng Y, Li D, Liang X, Chen Y, Cui Y, Yap PT, Qiu S, Zhang H, Shen D

Abstract
Major depressive disorder (MDD) is a serious mental illness characterized by dysfunctional connectivity among distributed brain regions. Previous connectome studies based on functional magnetic resonance imaging (fMRI) have focused primarily on undirected functional connectivity and existing directed effective connectivity (EC) studies concerned mostly task-based fMRI and incorporated only a few brain regions. To overcome these limitations and understand whether MDD is mediated by within-network or between-network connectivities, we applied spectral dynamic causal modeling to estimate EC of a large-scale network with 27 regions of interests from four distributed functional brain networks (default mode, executive control, salience, and limbic networks), based on large sample-size resting-state fMRI consisting of 100 healthy subjects and 100 individuals with first-episode drug-naive MDD. We applied a newly developed parametric empirical Bayes (PEB) framework to test specific hypotheses. We showed that MDD altered EC both within and between high-order functional networks. Specifically, MDD is associated with reduced excitatory connectivity mainly within the default mode network (DMN), and between the default mode and salience networks. In addition, the network-averaged inhibitory EC within the DMN was found to be significantly elevated in the MDD. The coexistence of the reduced excitatory but increased inhibitory causal connections within the DMNs may underlie disrupted self-recognition and emotional control in MDD. Overall, this study emphasizes that MDD could be associated with altered causal interactions among high-order brain functional networks.

PMID: 32026598 [PubMed - in process]

Abnormal Baseline Brain Activity in Neuromyelitis Optica Patients Without Brain Lesion Detected by Resting-State Functional Magnetic Resonance Imaging.

Thu, 02/06/2020 - 20:20
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Abnormal Baseline Brain Activity in Neuromyelitis Optica Patients Without Brain Lesion Detected by Resting-State Functional Magnetic Resonance Imaging.

Neuropsychiatr Dis Treat. 2020;16:71-79

Authors: Liu Y, Xiong H, Li X, Zhang D, Yang C, Yu J, Liao R, Zhou B, Huang X, Tang Z

Abstract
Objective: To investigate the baseline brain activity in neuromyelitis optica patients without brain lesion using the regional amplitude of low-frequency fluctuation (ALFF) and fractional amplitude of low-frequency fluctuation (fALFF) as indexes.
Materials and methods: Forty-two patients of NMO with normal performance in conventional MRI and 42 healthy controls, matched in gender and age, were enrolled in this study. Resting-state functional magnetic resonance imaging (rs-fMRI) data acquired using the rs-fMRI Data Analysis Toolkit. The relationships between expanded disability states scale (EDSS) scores, abnormal baseline brain activity and disease duration were explored.
Results: The left inferior temporal, left cerebellum_4_5, bilateral superior temporal pole, left caudate, right superior temporal, left middle frontal and left superior occipital showed significantly increased ALFF in the NMO. Regions of abnormal fALFF were similar to those of ALFF except that increased fALFF were also indicated in the right cerebellum crus2, right hippocampus, left parahippocampal gyrus and left supplementary motor area. Furthermore, a significant correlation between EDSS scores and ALFF/fALFF was noted in the left inferior temporal gyrus.
Conclusion: Results confirmed the disturbances in NMO-related neural networks, which probably be related to spinal cord damage.

PMID: 32021200 [PubMed]