Top PDF The anterior cingulate cortex

The anterior cingulate cortex

The anterior cingulate cortex

Sex differences. Examination with f�R showed sex differences in activity of the ventral (subgenual) ACC (BP �5) in the demanding task of metal rota- tion with complex visuospatial information process- ing (Butler et al., ���7). �ore ventral ACC activation Butler et al., ���7). �ore ventral ACC activation et al., ���7). �ore ventral ACC activation was found in women than in men during negative emotions. It seems that the suppression of the ven- tral ACC seen after strenuous cognitive activity and during negative emotions is present only in women. The amygdala-cingulate feedback circuit critical for emotional regulation is influenced by the short allele of a functional 5� promoter polymorphism of the serotonin transporter gene (Pe�awas et al., Pe�awas et al., et al., ���5). Subjects with this allele have reduced gray matter volume in the brain structures that mediate processing of negative emotions, mostly the peri- genual cingulate and amygdala. The repercussion of these changes is genetic susceptibility to depression. Individuals of male sex harboring the mono- amine oxydase-A (�AO-A) gene � version express lower en�yme acitivity and higher levels of sero- tonin (�eyer-�indenberg et al., ���6). This leads �eyer-�indenberg et al., ���6). This leads This leads to susceptibility to aggression (impulsive violence), but only in men who were abused as children, as they have only one copy of this allele on the X chromosome, whereas women have two alleles, one of which is usually the H variant. �en with the � variant show reduction in gray matter in the ACC and amygdale, while volume of the orbital frontal cortex is increased. It is hypothesi�ed that greater volume is due to deficient pruning. Greater activity was found in the amygdala, which mediates fear, while structures that regulate the amygdala (ACC, orbitofrontal and insular cortices) showed decreased
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Astrocyte activation in the anterior cingulate cortex and altered glutamatergic gene expression during paclitaxel-induced neuropathic pain in mice

Astrocyte activation in the anterior cingulate cortex and altered glutamatergic gene expression during paclitaxel-induced neuropathic pain in mice

Spinal astrocyte activation contributes to the pathogenesis of paclitaxel-induced neuropathic pain (PINP) in animal models. We examined glial fibrillary acidic protein (GFAP; an astrocyte marker) immunoreactivity and gene expression of GFAP, glutamate transporters and receptor subunits by real time PCR in the anterior cingulate cortex (ACC) at 7 days post first administration of paclitaxel, a time point when mice had developed thermal hyperalgesia. The ACC, an area in the brain involved in pain perception and modulation, was chosen because changes in this area might contribute to the pathophysiology of PINP. GFAP transcripts levels were elevated by more than fivefold and GFAP immunoreactivity increased in the ACC of paclitaxel-treated mice. The 6 glutamate transporters (GLAST, GLT-1 EAAC1, EAAT4, VGLUT-1 and VGLUT-2) quantified were not significantly altered by paclitaxel treatment. Of the 12 ionotropic glutamate receptor subunits transcripts analysed 6 (GLuA1, GLuA3, GLuK2, GLuK3, GLuK5 and GLuN1) were significantly up-regulated, whereas GLuA2, GLuK1, GLuK4, GLuN2A and GLuN2B were not significantly altered and GLuA4 was lowly expressed. Amongst the 8 metabotropic receptor subunits analysed only mGLuR8 was significantly elevated. In conclusion, during PINP there is astrocyte activation, with no change in glutamate transporter expression and differential up-regulation of glutamate receptor subunits in the ACC. Thus, targeting astrocyte activation and the glutamatergic system might be another therapeutic avenue for management of PINP.
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Higher media multi-tasking activity is associated with smaller gray-matter density in the anterior cingulate cortex.

Higher media multi-tasking activity is associated with smaller gray-matter density in the anterior cingulate cortex.

Media multitasking, or the concurrent consumption of multiple media forms, is increasingly prevalent in today’s society and has been associated with negative psychosocial and cognitive impacts. Individuals who engage in heavier media- multitasking are found to perform worse on cognitive control tasks and exhibit more socio-emotional difficulties. However, the neural processes associated with media multi-tasking remain unexplored. The present study investigated relationships between media multitasking activity and brain structure. Research has demonstrated that brain structure can be altered upon prolonged exposure to novel environments and experience. Thus, we expected differential engagements in media multitasking to correlate with brain structure variability. This was confirmed via Voxel-Based Morphometry (VBM) analyses: Individuals with higher Media Multitasking Index (MMI) scores had smaller gray matter density in the anterior cingulate cortex (ACC). Functional connectivity between this ACC region and the precuneus was negatively associated with MMI. Our findings suggest a possible structural correlate for the observed decreased cognitive control performance and socio- emotional regulation in heavy media-multitaskers. While the cross-sectional nature of our study does not allow us to specify the direction of causality, our results brought to light novel associations between individual media multitasking behaviors and ACC structure differences.
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Effect of monolingualism and bilingualism in the anterior cingulate cortex: a proton magnetic resonance spectroscopy study in two centers

Effect of monolingualism and bilingualism in the anterior cingulate cortex: a proton magnetic resonance spectroscopy study in two centers

Abutalebi et al. (2012) report a behavioral- neurostructural analysis i.e. correlations between conflict effects and structural data reporting an inverse correlation between mean GMV in the ACC and the conflict effect. They suggested that greater GMV is associated with smaller conflict effects for bilingual and monolingual participants. Functional-structural analysis i.e. correlations between functional activity provided by BOLd signal and GMV also showed a positive correlation between mean GMV and blood flow in ACC. Furthermore, a regression analysis showed that mean GMV was a predictor of ACC activation in bilingual and not monolingual participants. We found lower levels of mean metabolites in ACC that we contend are the direct result of bilingual language experience but this was not significantly related to any form of behavioural advantage. To summarize, young adult bilinguals exhibit reduced levels of metabolites in ACC even if the behavioural effects are equivalent. This confirms the sensitivity of brain imaging data relative to behavioural data and speaks directly to the debate about the bilingual advantage (P AAP; GREENBERG, 2013; VALIAN, 2014).
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Gene expression profile of sodium channel subunits in the anterior cingulate cortex during experimental paclitaxel-induced neuropathic pain in mice

Gene expression profile of sodium channel subunits in the anterior cingulate cortex during experimental paclitaxel-induced neuropathic pain in mice

In conclusion, the findings of this study show that sodium channel subunit transcripts are differentially expressed in the ACC; with those known to be preferentially expressed in the CNS being highly expressed in the ACC, whereas those known to be preferentially expressed in the periphery being lowly expressed in the ACC. More importantly, the results show that during experimental PINP there is increased expression of various sodium channel subunit transcripts in the ACC, which could contribute to the increased excitability and activity observed in this brain region during neuropathic pain.
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Age-related changes in the functional network underlying specific and general autobiographical memory retrieval: a pivotal role for the anterior cingulate cortex.

Age-related changes in the functional network underlying specific and general autobiographical memory retrieval: a pivotal role for the anterior cingulate cortex.

Although AM retrieval has been frequently associated with cortical midline activations [51,64], the exact role of the ACC - a region in the medial wall of the frontal lobe which is known to be fundamental to the integration of cognitive and affective processes - in accessing AM has never been a subject of specific debate. As previously mentioned, neuroimaging studies on EAM have pointed to the increasing activity of the frontal lobe associated with increasingly specific AMs, but mostly concerning lateral regions [26–27]. More specifically, the dLPFC is assumed to play a pivotal role in the controlled access phase of specific AM [26,65– 66]. Several researches have reported that emotion and cognition are processed in a ventral and a dorsal sub-region of the ACC respectively, the latter corresponding to the region found in our study [29,67]. The dorsal component is involved in various higher- order cognitive processes including different executive functions [68–71], and cognitively demanding tasks requiring stimulus– response selection in the face of competing streams of information [29,67,72]. This role of the dACC is coherent with its specific implication in EAM retrieval and with its link with the richness of specific details (episodic score) found here, since these memories are built up via generative processes which include strategic, evaluative and inhibitive processes [1,6,65]. The correlation between the dACC activity and the episodic and the inhibition scores of young and older participants could be in line with its frequently reported activation during the Stroop task [29,67] and suggests that probably inhibitory processes, more than other executive functions, are strongly recruited during the initial search of a specific memorie. Moreover, it is also consistent with studies that report age-related reduction of metabolism in the dACC [73]. Thus altogether, the pattern of activation of the dACC in EAM strategic retrieval suggests a central role of frontal/executive processes in the difficulty of reaching a higher level of AM specificity in aging [20]. Nevertheless, further evidence should be provided to confirm the present findings, since most of the correlations did not remain significant when correction for multiple comparisons was applied.
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Reduced fractional anisotropy of corpus callosum modulates inter-hemispheric resting state functional connectivity in migraine patients without aura.

Reduced fractional anisotropy of corpus callosum modulates inter-hemispheric resting state functional connectivity in migraine patients without aura.

Modern neuroimaging methods have explicated the neural substrate undying pain processing, namely pain matrix. It involves several cortical and subcortical brain regions, such as the thalamus, the amygdala, the insula cortex, the SMA, the posterior parietal cortex, the prefrontal cortex, the ACC, the periaqueductal gray, the basal ganglia, cerebellar cortex, the primary and secondary sensory cortex [15,47]. As a key component of pain matrix, both structural and functional studies explicates ACC’s pivotal role in pain processing. Previous studies revealed that the affective responses of pain, such as unpleasantness, suffering and other negative effects, may be principally integrated in ACC [48,49,50,51]. ACC is also involved in endogenous pain control, which is mediated by the endogenous opioid systems [52,53]. The role of the ACC in migraine has been underpinned by recent neuroimaging studies. Positron emission tomography (PET) studies have shown an association between pain and abnormal activation of the ACC in migraine patients [5,6]. Reduced regional homogeneity (ReHo) value of the BOLD signal in ACC was also Figure 2. Voxel-mirrored homotopic connectivity (VMHC) analysis results between migraine patients and healthy controls. a). Resting state analysis revealed the reduced VMHC value of the ACC in migraine patients without aura. The VMHC value of the anterior cingulate cortex (ACC) was correlated with duration of migraine. b). The bilateral ACC were chosen as the region of interest (ROI) for subsequent seeding-based resting state functional connectivity (RSFC).
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Psychol. Neurosci.  vol.4 número2

Psychol. Neurosci. vol.4 número2

The involvement of multiple prefrontal areas during emotional regulation and its relationship with amygdala activity has raised the question of which speciic subdivisions of the PFC are involved in the different forms of emotional regulation. Studies on cognitive reevaluation (reappraisal) observed a signiicant activation pattern in the PFC (dorsal and lateral regions) associated with a decrease in amygdala activation, thus suggesting that the former might modulate its activity through top-down inhibitory mechanisms (Beauregard et al., 2001; Ochsner et al., 2002; Levesque et al., 2003, 2004; Ochsner et al., 2004; Ochsner & Gross, 2005; Phan et al., 2005; Ray et al., 2005; Ohira et al., 2006). Eippert et al. (2007) investigated the effect of PFC modulation of amygdala activity during the visualization of threat-related pictures. The authors used functional magnetic resonance imaging (fMRI) to investigate the brain structures activated when volunteers visualized threat-related images. The volunteers were instructed to regulate their emotions through strategies of cognitive reevaluation to increase or decrease their emotional responses. A decrease in negative affect during the visualization of threatening images was associated with activation of the anterior cingulate cortex, dlPFC, and left OFC. The same activation pattern was found bilaterally during the increase in negative affect. Both an increase and decrease in amygdala activity was observed during the use of emotional regulation strategies aimed at increasing and decreasing negative affect, respectively. This work demonstrated that the amygdala responses to threat-related stimuli can be modulated by cognitive strategies depending on the recruitment of prefrontal regions (Eippert et al., 2007). A similar study (Urry et al., 2006) supported this hypothesis. The relationship between responses of the PFC and amygdala during emotional regulation was
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Análise quantitativa das descargas epileptiformes generalizadas e da neuroimagem de pacientes com epilepsia generalizada idiopática

Análise quantitativa das descargas epileptiformes generalizadas e da neuroimagem de pacientes com epilepsia generalizada idiopática

Methods: 75 EEG recordings from 64 patients were analyzed. The first unequivocally confirmed generalized spike was marked for each discharge. Three methods of source imaging analysis were applied: dipole source imaging (DSI), classical LORETA analysis recursively applied (CLARA), and equivalent dipole of independent components with cluster analysis. After EEG analysis, 32 patients (18 women, 30± 10 years) and 36 controls (18 women, 32 ±11 years) were imaged by 3 Tesla magnetic resonance (MRI). We used three models to compare cingulate gyrus of patients and the control group: voxel-based morphometry (VBM), cortical analyses and shape analyses. Results: A total of 753 GSW discharges were spatiotemporally analyzed. Source analysis using all three techniques revealed that the frontal lobe was the principal source of GSW discharges (70%), followed by the parietal and occipital lobes (14%), and the basal ganglia (12%). The main anatomical sources of the generalized discharges were the anterior cingulate cortex (36%) and the medial frontal gyrus (23%). VBM analyses of cingulate gyrus showed areas of gray matter atrophy, mainly in the anterior cingulate gyrus (972 mm3) and the isthmus (168 mm3). Individual analyses of the cingulate cortex were similar between patients with IGE and controls. Surface- based comparisons revealed abnormalities located mainly in the posterior cingulate cortex (718.12 mm2). Shape analyses demonstrated a predominance of abnormalities in the anterior and posterior portions of cingulate gyrus abnormalities.
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Mapping brain response to pain in fibromyalgia patients using temporal analysis of FMRI.

Mapping brain response to pain in fibromyalgia patients using temporal analysis of FMRI.

Our results are consistent with most of previous fMRI studies on fibromyalgia, but expand the reported data by assessing the temporal dynamics of brain activity, which led to a more comprehensive activation mapping. All the reports coincide in showing abnormal brain responses to painful stimuli in fibromyalgia patients [20,35,36] when comparing patients to control subjects receiving identical stimulus intensity. In general, the data are consistent with a model of enhanced normal pain response and argues against the occurrence of ‘‘aberrant’’ nociception [20,37]. However, when matching both groups for perceived pain we observed larger activations in patients for specific regions. In this matching comparison, Gracely et al. [20] did not report significant differences between patients and control subjects with stimulation producing moderate pain. More recently, Staud et al. [9] specifically assessed the temporal summation of second pain using heat stimulation and also found no brain activation differences when stimulus strength was adjusted to induce moderate pain in both groups. In contrast with these two studies, more intense stimulation was used in our assessment and both patients and this control group reported severe pain. Fibromyalgia patients showed greater activation in the insula, basal ganglia and the anterior cingulate cortex, which are part of the brain network mediating efferent aspects of the pain response, and not in somatosensory cortices, where control subjects even had a tendency to show larger activation. Overall, our findings may be consistent with the notion of augmented brain response to pain in fibromyalgia, but the functional alterations may be particularly relevant in emotion-related (para- limbic) regions.
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Altered regional homogeneity in pediatric bipolar disorder during manic state: a resting-state fMRI study.

Altered regional homogeneity in pediatric bipolar disorder during manic state: a resting-state fMRI study.

Pediatric bipolar disorder (PBD) is a severely debilitating illness, which is characterized by episodes of mania and depression separated by periods of remission. Previous fMRI studies investigating PBD were mainly task-related. However, little is known about the abnormalities in PBD, especially during resting state. Resting state brain activity measured by fMRI might help to explore neurobiological biomarkers of the disorder. Methods: Regional homogeneity (ReHo) was examined with resting-state fMRI (RS-fMRI) on 15 patients with PBD in manic state, with 15 age-and sex-matched healthy youth subjects as controls. Results: Compared with the healthy controls, the patients with PBD showed altered ReHo in the cortical and subcortical structures. The ReHo measurement of the PBD group was negatively correlated with the score of Young Mania Rating Scale (YMRS) in the superior frontal gyrus. Positive correlations between the ReHo measurement and the score of YMRS were found in the hippocampus and the anterior cingulate cortex in the PBD group. Conclusions: Altered regional brain activity is present in patients with PBD during manic state. This study presents new evidence for abnormal ventral- affective and dorsal-cognitive circuits in PBD during resting state and may add fresh insights into the pathophysiological mechanisms underlying PBD.
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Rev. Bras. Psiquiatr.  vol.30 número3

Rev. Bras. Psiquiatr. vol.30 número3

Objective: The aim of the present report is to present a systematic and critical review of the more recent literature data about structural abnormalities detected by magnetic ressonance in anxiety disorders. Method: A review of the literature in the last five years was conducted by a search of the Medline, Lilacs and SciELO indexing services using the following key words: “anxiety”, “panic”, “agoraphobia”, “social anxiety”, “posttraumatic” and “obsessive-compulsive”, crossed one by one with “magnetic resonance”, “voxel-based”, “ROI” and “morphometry”. Results: We selected 134 articles and 41 of them were included in our review. Recent studies have shown significant morphological abnormalities in various brain regions of patients with anxiety disorders and healthy controls. Despite some apparently contradictory findings, perhaps reflecting the variability and limitations of the methodologies used, certain brain regions appear to be altered in a consistent and relatively specific manner in some anxiety disorders. These include the hippocampus and the anterior cingulate cortex in posttraumatic stress disorder and the orbitofrontal cortex in obsessive-compulsive disorder. Conclusions: The present review indicates that structural neuroimaging has contributed to a better understanding of the neurobiology of anxiety disorders. Further development of neuroimaging techniques, better sample standardization and the integration of data across neuroimaging modalities may extend progress in this area.
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Positive Allosteric Modulator of GABA Lowers BOLD Responses in the Cingulate Cortex.

Positive Allosteric Modulator of GABA Lowers BOLD Responses in the Cingulate Cortex.

In this study, we aimed to investigate if DZ attenuates brain activation in the cingulate cortex during a working memory task. Therefore we did small volume corrections within the entire cingulate cortex to investigate if there were any pure task-related effects or evidence for DZ- modulation of brain activation during the working memory task. In follow-up analyses, we investigated these effects in cingulate subregions by making statistical analyses in predefined regions of interest (ROI) in the cingulate cortex based on cytoarchitecture and functional stud- ies. The cingulate cortex is divided into four main sub-regions with different cytoarchitectures and functions: the anterior cingulate cortex (ACC), the midcingulate cortex (MCC), the poste- rior cingulate cortex (PPC), and the retrosplenial cortex [23]. The ACC is further subdivided into a subgenual (sACC) and a pregenual (pACC) portion, which are thought to be involved with affective and autonomic responses, and emotional integration, respectively [18, 23]. The MCC is also subdivided into two different compartments: the anterior MCC (aMCC), which is involved in cognition, and the posterior MCC (pMCC), which is involved in skeletomotor ori- entation [24]. The role of the PCC is multifaceted; it is thought to be involved in diverse func- tions such as autobiographical memory, spatial learning, and mind wandering [25]. Image masks of the PCC (size = 122 voxels), pMCC (size = 515 voxels), aMCC (size = 217 voxels), pACC (size = 180 voxels), and the sACC (size = 68 voxels) were constructed from the Wake Forrest University (WFU) Pick Atlas [26] and the MarsBaR ROI toolbox [27] based on the descriptions in [23]. Voxels sizes are given as mean value of left and right hemisphere ROIs, since the ROIs were slightly asymmetric.
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Arq. NeuroPsiquiatr.  vol.73 número7

Arq. NeuroPsiquiatr. vol.73 número7

were associated with atrophy in the left frontal lobe, right frontoparietal cortex and left claustrum. Apathy was associated with atrophy in anterior cingulate, medial frontal cortex and putamen bilaterally, and also with the head of left caudate nucleus. Agitation corre- lated with gray matter loss in left insula and anterior cingulate cortex bilaterally. Another study 6 showed that agitation was related to atrophy in the left inferior and middle frontal/

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Dement. neuropsychol.  vol.9 número4

Dement. neuropsychol. vol.9 número4

observations have indicated that these areas are related to both visual and auditory brain processing. Other brain areas are claimed to be activated under olfactory stimu- lation, such as the more inferior parts of the anterior cingulate, temporal and occipital lobes, with butyric acid or vanilla inhalation. No signiicant diference was noted by these investigations in the amygdaloid body or in the entorhinal cortex. An event-related fMRI-design experi- ment study consisting of semantic modulation suggests that the afective value of the test odor is signiicantly more unpleasant when labeled with body odor than when classiied as cheddar cheese in the odorant trial. In this case, activation of the rostral anterior cingulate cortex and medial orbitofrontal cortex are associated to plea- santness ratings. his cognitive modulation was also per- ceived for the odorant test in the amygdala bilaterally. 34
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Avaliação volumétrica e neuroquímica do córtex pré-frontal dorsolateral esquerdo...

Avaliação volumétrica e neuroquímica do córtex pré-frontal dorsolateral esquerdo...

Magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy ( 1 H MRS) have been applied to anatomical and neurochemical studies of adult patients with Major Depressive Disorder (MDD). They have demonstrated abnormalities in specific structures that are involved in mood regulation, expression and recognition. In our study, our hypotheses were that children and adolescents with MDD would present both smaller left dorsolateral prefrontal cortex (DLPFC) and left hippocampal volumes compared to healthy children; and no significant abnormalities in amygdala, caudate, putamen, thalamus, anterior cingulate and total brain volumes; and lower levels of glycerophosphocholine plus phosphocholine (GPC+PC; or choline-containing- compounds) and higher myo-inositol levels in the left DLPFC. Nineteen children and adolescents (9 off medication), mean age of 13.0 (± 2.4) years old, who fulfilled diagnostic criteria for MDD (DSM-IV) and 24 healthy controls, mean age of 13,9 (± 2.9) years old, were evaluated on a 1.5 Tesla (Philips Intera 8.1.1.) MRI scanner to obtain volumetric measurements. We also conducted single voxel of the left DLPFC in 14 (73.7%) of the 19 patients with MDD, mean age of 13.3 ± 2.3 years old, and in 22 (91.7%) of the 24 healthy controls, mean age of 13.6 (±2.8) years old. Compared to healthy controls, children and adolescents with MDD presented: (i) significantly smaller left hippocampal gray matter volumes (p=0.032), and (ii) significantly lower levels of glycerophosphocholine plus phosphocholine [GPC+PC; or choline-containing- compounds (p= 0.002)] and higher myo-inositol levels [Ino (p= 0.001)] in the left DLPFC. Our findings of smaller left hippocampal volumes in children and adolescents with MDD are in agreement with studies conducted in adults with MDD. Lower levels of choline-containing-compounds (GPC+PC) in pediatric patients with MDD may reflect lower cell membrane turn-over. Higher myo-inositol levels in MDD may represent a disturbed secondary messengers system. Our findings provide further support to the existence of anatomical and neurochemical abnormalities in children and adolescents with MDD.
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Rev. CEFAC  vol.19 número4

Rev. CEFAC vol.19 número4

employing fMRI to study professional opera singers, with the intention of identifying brain regions used for voluntary and involuntary correction of the pitch by means of vocal motor integration. Initially the authors emphasized the importance of considering the constel- lation of neural structures involved in adjusting the pitch while singing. This complex network included motor/ pre-motor cortical networks (including the primary motor cortex, supplementary motor area, and anterior cingulate cortex), subcortical regions (such as the basal ganglia and thalamus), as well as structures in the brain stem, including the periaqueductal gray matter, substantia nigra, the reticular formation, and the band of motor neurons. This entire network of structures and their interconnections were involved in the production of correct pitch, as seen in loud environments where the interlocutors augmented or reduced the intensity of their speech to facilitate communication without losing the emotion of the message. The authors 4 compared
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Radiol Bras

Radiol Bras

Materials and Methods: Inpatient crack-cocaine users who had been abstinent for at least four weeks and age-matched non-drug- using controls underwent resting state functional magnetic resonance imaging. Images were acquired while the subjects rested with their eyes closed. After data preprocessing, DMNs were deined by spatial independent component analysis and seed-based cor- relation analysis, by chosen regions of interest centered in the ventral anterior cingulate cortex and in the posterior cingulate cortex. Results: The functional connectivity of the DMN determined by independent component analysis did not differ between the crack- cocaine users and the controls. However, the seed-based correlation analysis seeking a single metric of functional connectivity between speciic brain regions showed that the negative connectivity between the ventral anterior cingulate cortex and the left superior parietal lobule was signiicantly greater in the crack-cocaine users than in the controls.
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Migraine improvement correlates with posterior cingulate cortical thickness reduction

Migraine improvement correlates with posterior cingulate cortical thickness reduction

This was one of the first attempts to correlate improve- ment of cortical thickness pre- and post-treatment in migraine. After multiple comparisons correction, only the right hemisphere showed thickness changes (increase), in patients vs. controls, located in the somatosensory and superior parietal cortices, both in the first and second scans. In addition, the right cortex was thicker in the second scan in the precentral, supramarginal, cuneus and precuneus when compared to controls. The effect size analysis showed small changes in various areas, specifically in the lingual, fusiform and caudal anterior cingulate cortices on the left (thickness reduction); and caudal middle frontal, pars triangularis, and rostral middle frontal (thickness reduction), and transverse temporal (thickness increase) cortices on the right. Patients improved significantly following treatment as shown by the HI reduction, but there were no corresponding changes in cortical thickness after correction for multiple comparison. Regression analysis showed significant negative correlations between the HI improvement and cortical thickness changes only in the left hemisphere.
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Frontostriatal grey matter atrophy in amyotrophic lateral sclerosis

Frontostriatal grey matter atrophy in amyotrophic lateral sclerosis

ABSTRACT. Amyotrophic lateral sclerosis (ALS) is characterised by frontostriatal grey matter changes similar to those in frontotemporal dementia (FTD). However, these changes are usually detected at a group level, and simple visual magnetic resonance imaging (MRI) cortical atrophy scales may further elucidate frontostriatal changes in ALS. Objective: To investigate whether frontostriatal changes are detectable using simple visual MRI atrophy rating scales applied at an individual patient level in ALS. Methods: 21 ALS patients and 17 controls were recruited and underwent an MRI scan. Prefrontal cortex sub-regions of the medial orbitofrontal cortex (MOFC), lateral orbitofrontal cortex (LOFC) and anterior cingulate cortex (ACC), striatal sub-regions of the caudate nucleus (CN) and nucleus accumbens (NAcc) were rated using visual grey matter atrophy 5-point Likert scales. Results: Significantly higher atrophy ratings in the bilateral MOFC only in ALS patients versus controls was observed (p<.05). Patients with greater MOFC atrophy had significantly higher atrophy of the CN (p<.05) and LOFC (p<.05). Conclusion: Use of simple visual atrophy rating scales on an individual level reliably detects frontostriatal deficits specific to ALS, showing MOFC atrophy differences with associated CN and LOFC atrophy. This is an applicable method that could be used to support clinical diagnosis and management. Key words: amyotrophic lateral sclerosis, magnetic resonance imaging, orbitofrontal cortex, striatum, visual atrophy rating scale.
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