scholarly journals Preservation Effect: Cigarette Smoking Acts on the Dynamic of Influences Among Unifying Neuropsychiatric Triple Networks in Schizophrenia

2018 ◽  
Vol 45 (6) ◽  
pp. 1242-1250 ◽  
Author(s):  
Wei Liao ◽  
Yun-Shuang Fan ◽  
Siqi Yang ◽  
Jiao Li ◽  
Xujun Duan ◽  
...  
Keyword(s):  
Cigarette Smoking ◽  
Analysis Of Covariance ◽  
Neural Pathways ◽  
Healthy Controls ◽  
Causality Analysis ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Self Medication ◽  
Granger Causality Analysis ◽  
High Prevalence

Abstract Objective The high prevalence of cigarette smoking in schizophrenia (SZ) is generally explained by the self-medication theory. However, its neurobiological mechanism remains unclear. The impaired dynamic of influences among unifying neuropsychiatric triple networks in SZ, including the central executive network (CEN), the default mode network (DMN), and the salience network (SN), might explain the nature of their syndromes, whereas smoking could regulate the dynamics within networks. Therefore, this study examined whether cigarette smoking could elicit a distinct improvement in the dynamics of triple networks in SZ and associated with the alleviation of symptoms. Methods Four groups were recruited, namely, SZ smoking (n = 22)/nonsmoking (n = 25), and healthy controls smoking (n = 22)/nonsmoking (n = 21). All participants underwent a resting-state functional magnetic resonance imaging (fMRI). The dynamics among unifying neuropsychiatric triple networks were measured using Granger causality analysis on the resting-sate fMRI signal. Interaction effects between SZ and smoking on dynamics were detected using 2-way analysis of covariance, correcting for sex, age, and education level. Results Whereas smoking reduced SN→DMN dynamic in healthy controls, it preserved the dynamic in SZ, thus suggesting a preservation effect. Moreover, smoking additionally increased DMN→CEN dynamic in SZ. Conclusions This finding from neural pathways shed new insights into the prevailing self-medication hypothesis in SZ. More broadly, this study elaborates on the neurobiological dynamics that may assist in the treatment of the symptomatology of SZ.

scholarly journals Altered sense of agency in Gilles de la Tourette syndrome: behavioural, clinical and functional magnetic resonance imaging findings

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Laura Zapparoli ◽  
Silvia Seghezzi ◽  
Francantonio Devoto ◽  
Marika Mariano ◽  
Giuseppe Banfi ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Functional Magnetic Resonance Imaging ◽  
Tourette Syndrome ◽  
Sense Of Agency ◽  
Healthy Controls ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Intentional Binding ◽  
Action Monitoring

Abstract Current neurocognitive models of motor control postulate that accurate action monitoring is crucial for a normal experience of agency—the ability to attribute the authorship of our actions and their consequences to ourselves. Recent studies demonstrated that action monitoring is impaired in Gilles de la Tourette syndrome, a movement disorder characterized by motor and vocal tics. It follows that Tourette syndrome patients may suffer from a perturbed sense of agency, the hypothesis tested in this study. To this end, we recruited 25 Tourette syndrome patients and 25 matched healthy controls in a case-control behavioural and functional magnetic resonance imaging study. As an implicit index of the sense of agency, we measured the intentional binding phenomenon, i.e., the perceived temporal compression between voluntary movements and their external consequences. We found evidence of an impaired sense of agency in Tourette syndrome patients who, as a group, did not show a significant intentional binding. The more reduced was the individual intentional binding, the more severe were the motor symptoms. Specific differences between the two groups were also observed in terms of brain activation patterns. In the healthy controls group, the magnitude of the intentional binding was associated with the activity of a premotor–parietal–cerebellar network. This relationship was not present in the Tourette syndrome group, suggesting an altered activation of the agency brain network for self-generated acts. We conclude that the less accurate action monitoring described in Tourette syndrome also involves the assessment of the consequences of actions in the outside world. We discuss that this may lead to difficulties in distinguishing external consequences produced by their own actions from the ones caused by others in Tourette syndrome patients.

scholarly journals Resting-State Functional Magnetic Resonance Imaging Connectivity Between Semantic and Phonological Regions of Interest May Inform Language Targets in Aphasia

2020 ◽  
Vol 63 (9) ◽  
pp. 3051-3067
Author(s):  
Amy E. Ramage ◽  
Semra Aytur ◽  
Kirrie J. Ballard
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Functional Magnetic Resonance Imaging ◽  
Resting State ◽  
Brain Regions ◽  
Regions Of Interest ◽  
Healthy Controls ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Language Performance

Purpose Brain imaging has provided puzzle pieces in the understanding of language. In neurologically healthy populations, the structure of certain brain regions is associated with particular language functions (e.g., semantics, phonology). In studies on focal brain damage, certain brain regions or connections are considered sufficient or necessary for a given language function. However, few of these account for the effects of lesioned tissue on the “functional” dynamics of the brain for language processing. Here, functional connectivity (FC) among semantic–phonological regions of interest (ROIs) is assessed to fill a gap in our understanding about the neural substrates of impaired language and whether connectivity strength can predict language performance on a clinical tool in individuals with aphasia. Method Clinical assessment of language, using the Western Aphasia Battery–Revised, and resting-state functional magnetic resonance imaging data were obtained for 30 individuals with chronic aphasia secondary to left-hemisphere stroke and 18 age-matched healthy controls. FC between bilateral ROIs was contrasted by group and used to predict Western Aphasia Battery–Revised scores. Results Network coherence was observed in healthy controls and participants with stroke. The left–right premotor cortex connection was stronger in healthy controls, as reported by New et al. (2015) in the same data set. FC of (a) connections between temporal regions, in the left hemisphere and bilaterally, predicted lexical–semantic processing for auditory comprehension and (b) ipsilateral connections between temporal and frontal regions in both hemispheres predicted access to semantic–phonological representations and processing for verbal production. Conclusions Network connectivity of brain regions associated with semantic–phonological processing is predictive of language performance in poststroke aphasia. The most predictive connections involved right-hemisphere ROIs—particularly those for which structural adaptions are known to associate with recovered word retrieval performance. Predictions may be made, based on these findings, about which connections have potential as targets for neuroplastic functional changes with intervention in aphasia. Supplemental Material https://doi.org/10.23641/asha.12735785

Depression is associated with disconnection of neurotransmitter-related nuclei in multiple sclerosis

2020 ◽  
pp. 135245852094821
Author(s):  
Matteo Martino ◽  
Paola Magioncalda ◽  
Mohamed Mounir El Mendili ◽  
Amgad Droby ◽  
Swetha Paduri ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Resting State ◽  
Depressive Symptomatology ◽  
Healthy Controls ◽  
Diffusion Weighted Mri ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Functional Connections ◽  
Brainstem Nuclei ◽  
And Diffusion

Background: Depression is frequently associated with multiple sclerosis (MS). However, the biological background underlying such association is poorly understood. Objective: Investigating the functional connections of neurotransmitter-related brainstem nuclei, along with their relationship with white matter (WM) microstructure, in MS patients with depressive symptomatology (MS-D) and without depressive symptomatology (MS-nD). Methods: Combined resting-state functional magnetic resonance imaging (fMRI) and diffusion-weighted MRI (dMRI) study on 50 MS patients, including 19 MS-D and 31 MS-nD patients, along with 37 healthy controls (HC). Main analyses performed are (1) comparison between groups of raphe nuclei (RN)-related functional connectivity (FC); (2) correlation between RN-related FC and whole brain dMRI-derived fractional anisotropy (FA) map; and (3) comparison between groups of FA in the RN-related WM area. Results: (1) RN-related FC was reduced in MS-D when compared to MS-nD and HC; (2) RN-related FC positively correlated with FA in a WM cluster mainly encompassing thalamic/basal ganglia regions, including the fornix; and (3) FA in such WM area was reduced in MS-D. Conclusion: Depressive symptomatology in MS is specifically associated to a functional disconnection of neurotransmitter-related nuclei, which in turn may be traced to a distinct spatial pattern of WM alterations mainly involving the limbic network.

scholarly journals The medial thalamus plays an important role in the cognitive and emotional modulation of orofacial pain: a functional magnetic resonance imaging-based study

2020 ◽  
Author(s):  
Yu Jin ◽  
Hong Yang ◽  
Feifei Zhang ◽  
Jue Wang ◽  
He Liu ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Orofacial Pain ◽  
Brain Regions ◽  
Healthy Controls ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Emotional Modulation ◽  
Pain Group ◽  
Medial Thalamus ◽  
Dorsal Thalamus

Abstract Background The thalamus plays a critical role in the perception of orofacial pain. We investigated the neural mechanisms of orofacial pain by exploring the intrinsic functional alterations of the thalamus and assessing the changes in functional connectivity (FC) between the thalamic subregions with significant functional alterations and other brain regions in orofacial pain using the seed-based FC approach. Methods The study comprised 49 participants in the orofacial pain group and 49 healthy controls. Orofacial pain was caused by orthodontic separators. The resting-state functional magnetic resonance imaging data of the two groups were analyzed to obtain the fractional amplitude of low-frequency fluctuations (fALFFs) of the thalamus, and the thalamic subregions with significant fALFF abnormalities were used as seeds for FC analysis. Student’s t-tests were used to perform comparisons. Pearson’s correlation analysis was performed using SPM software. Results Forty-four participants with orofacial pain (mean age, 21.0±0.9 years; 24 women) and 49 age- and sex-matched healthy controls (mean age, 21.0±2.6 years; 27 women) were finally included. Compared with the control group, the orofacial pain group demonstrated (1) increased function in the dorsal thalamus and decreased function in the medial thalamus; (2) decreased FC between the medial thalamus and 12 brain regions (p<0.05, family-wise error corrected, voxel>100); and (3) potential positive and negative correlations between the medial thalamus-seeded FC and visual analog scale score changes (p<0.05, AlphaSim corrected). Conclusions The findings show that the medial and dorsal thalamus play important roles in orofacial pain perception and that the medial thalamus likely plays an important role in the cognitive and emotional modulation of orofacial pain.

scholarly journals Acute Effect of Betel Quid Chewing on Brain Network Dynamics: A Resting-State Functional Magnetic Resonance Imaging Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiaojun Huang ◽  
Zhipeng Wu ◽  
Zhening Liu ◽  
Dayi Liu ◽  
Danqing Huang ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Functional Magnetic Resonance Imaging ◽  
Resting State ◽  
Brain Network ◽  
Analysis Of Covariance ◽  
Betel Quid ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Switching Rate

Betel quid (BQ) is one of the most popular addictive substances in the world. However, the neurophysiological mechanism underlying BQ addiction remains unclear. This study aimed to investigate whether and how BQ chewing would affect brain function in the framework of a dynamic brain network model. Resting-state functional magnetic resonance imaging scans were collected from 24 male BQ-dependent individuals and 26 male non-addictive healthy individuals before and promptly after chewing BQ. Switching rate, a measure of temporal stability of functional brain networks, was calculated at both global and local levels for each scan. The results showed that BQ-dependent and healthy groups did not significantly differ on switching rate before BQ chewing (F = 0.784, p = 0.381, analysis of covariance controlling for age, education, and head motion). After chewing BQ, both BQ-dependent (t = 2.674, p = 0.014, paired t-test) and healthy (t = 2.313, p = 0.029, paired t-test) individuals showed a significantly increased global switching rate compared to those before chewing BQ. Significant corresponding local-level effects were observed within the occipital areas for both groups, and within the cingulo-opercular, fronto-parietal, and cerebellum regions for BQ-dependent individuals. Moreover, in BQ-dependent individuals, switching rate was significantly correlated with the severity of BQ addiction assessed by the Betel Quid Dependence Scale scores (Spearman's rho = 0.471, p = 0.020) before BQ chewing. Our study provides preliminary evidence for the acute effects of BQ chewing on brain functional dynamism. These findings may provide insights into the neural mechanisms of substance addictions.

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