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THE ANTERIOR CINGULATE CORTEX IS A TARGET STRUCTURE FOR THE ANXIOLYTIC-LIKE EFFECTS OF BENZODIAZEPINES ASSESSED BY REPEATED EXPOSURE TO THE ELEVATED PLUS MAZE AND FOS IMMUNOREACTIVITY

ALBRECHET-SOUZA, L.; BORELLI, K. G.; CARVALHO, M. C.; BRANDAO, M. L.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
86.33%
Prior experience with the elevated plus maze (EPM) increases the avoidance of rodents to the open arms and impairs the anxiolytic-like effects of benzodiazepines on the traditional behaviors evaluated upon re-exposure to the maze, a phenomenon known as one-trial tolerance. Risk assessment behaviors are also sensitive to benzodiazepines. During re-exposure to the maze, these behaviors reinstate the information-processing initiated during the first experience, and the detection of danger generates stronger open-arm avoidance. The present study investigated whether the benzodiazepine midazolam alters risk assessment behaviors and Fos protein distribution associated with test and retest sessions in the EPM. Naive or maze-experienced Wistar rats received either saline or midazolam (0.5 mg/kg i.p.) and were subjected to the EPM. Midazolam caused the usual effects on exploratory behavior, increasing exploratory activity of naive rats in the open arms and producing no effects on these conventional measures in rats re-exposed to the maze. Risk assessment behaviors, however, were sensitive to the benzodiazepine during both sessions, indicating anxiolytic-like effects of the drug in both conditions. Fos immunohistochemistry showed that midazolam injections were associated with a distinct pattern of action when administered before the test or retest session...

A population-based morphometric MRI study in patients with first-episode psychotic bipolar disorder: comparison with geographically matched healthy controls and major depressive disorder subjects

PERICO, Cintia de Azevedo-Marques; DURAN, Fabio L. S.; ZANETTI, Marcus V.; SANTOS, Luciana C.; MURRAY, Robin M.; SCAZUFCA, Marcia; MENEZES, Paulo R.; BUSATTO, Geraldo F.; SCHAUFELBERGER, Maristela S.
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.54%
Objectives: Many morphometric magnetic resonance imaging (MRI) studies that have investigated the presence of gray matter (GM) volume abnormalities associated with the diagnosis of bipolar disorder (BD) have reported conflicting findings. None of these studies has compared patients with recent-onset psychotic BD with asymptomatic controls selected from exactly the same environment using epidemiological methods, or has directly contrasted BD patients against subjects with first-onset psychotic major depressive disorder (MDD). We examined structural brain differences between (i) BD (type I) subjects and MDD subjects with psychotic features in their first contact with the healthcare system in Brazil, and (ii) these two mood disorder groups relative to a sample of geographically matched asymptomatic controls. Methods: A total of 26 BD subjects, 20 subjects with MDD, and 94 healthy controls were examined using either of two identical MRI scanners and acquisition protocols. Diagnoses were based on DSM-IV criteria and confirmed one year after brain scanning. Image processing was conducted using voxel-based morphometry. Results: The BD group showed increased volume of the right dorsal anterior cingulate cortex relative to controls, while the MDD subjects exhibited bilateral foci GM deficits in the dorsolateral prefrontal cortex (p < 0.05...

Physiological Responses to Brain Stimulation During Limbic Surgery: Further Evidence of Anterior Cingulate Modulation of Autonomic Arousal

GENTIL, Andre Felix; ESKANDAR, Emad N.; MARCI, Carl David; EVANS, Karleyton Conroy; DOUGHERTY, Darin Dean
Fonte: ELSEVIER SCIENCE INC Publicador: ELSEVIER SCIENCE INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
76.38%
Background: In view of conflicting neuroimaging results regarding autonomic-specific activity within the anterior cingulate cortex (ACC), we investigated autonomic responses to direct brain stimulation during sterecitactic limbic surgery. Methods: Skin conductance activity and accelerative heart rate responses to multi-voltage stimulation of the ACC (n = 7) and paralimbic subcauclate (n = 5) regions were recorded during bilateral anterior cingulotomy and bilateral subcauclate tractotomy (in patients that had previously received an adequate lesion in the ACC), respectively. Results: Stimulations in both groups were accompanied by increased autonomic arousal. Skin conductance activity was significantly increased during ACC stimulations compared with paralimbic targets at 2 V (2.34 +/- .68 [score in microSiemens +/- SE] vs. .34 +/- .09, p = .013) and 3 V (3.52 +/- .86 vs. 1.12 +/- .37, p = .036), exhibiting a strong ""voltage-response"" relationship between stimulus magnitude and response amplitude (difference from 1 to 3 V = 1.15 +/- .90 vs. 3.52 +/- .86, p = .041). Heart rate response was less indicative of between-group differences. Conclusions: This is the first study of its kind aiming at seeking novel insights into the mechanisms responsible for central autonomic modulation. It supports a concept that interregional interactions account for the coordination of autonomic arousal.; Howard Hughes Medical Institute; National Association for Research on Schizophrenia and Depression (NARSAD); CePhalon; Cyheronics; Medtronic; Northstar Neuroscience; Pfizer; Forest

Anterior cingulate volumes associated with trait impulsivity in individuals with bipolar disorder

MATSUO, Koji; NICOLETTI, Mark A.; PELUSO, Marco A. M.; HATCH, John P.; NEMOTO, Kiyotaka; WATANABE, Yoshifumi; NERY, Fabiano G.; MONKUL, E. Serap; ZUNTA-SOARES, Giovana B.; BOWDEN, Charles L.; SOARES, Jair C.
Fonte: WILEY-BLACKWELL PUBLISHING, INC Publicador: WILEY-BLACKWELL PUBLISHING, INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
76.4%
Objective: Impulsivity is associated with the clinical outcome and likelihood of risky behaviors among bipolar disorder (BD) patients. Our previous study showed an inverse relationship between impulsivity and orbitofrontal cortex (OFC) volume in healthy subjects. We hypothesized that BD patients would show an inverse relationship between impulsivity and volumes of the OFC, anterior cingulate cortex (ACC), medial prefrontal cortex, and amygdala, which have been implicated in the pathophysiology of BD. Methods: Sixty-three BD patients were studied (mean +/- SD age = 38.2 +/- 11.5 years; 79% female). The Barratt Impulsiveness Scale (BIS), version 11A, was used to assess trait impulsivity. Images were processed using SPM2 and an optimized voxel-based morphometry protocol. We examined the correlations between BIS scores and the gray matter (GM) and white matter (WM) volumes of the prespecified regions. Results: Left rostral ACC GM volume was inversely correlated with the BIS total score (t = 3.95, p(corrected) = 0.003) and the BIS motor score (t = 5.22, p(corrected) < 0.001). In contrast to our hypothesis, OFC volumes were not significantly associated with impulsivity in BD. No WM volume of any structure was significantly correlated with impulsivity. No statistical association between any clinical variable and the rostral ACC GM volumes reached significance. Conclusions: Based on our previous findings and the current results...

Role of homocysteic acid in the guinea pig (Cavia porcellus) anterior cingulate cortex in tonic immobility and the influence of NMDA receptors on the dorsal PAG

COUTINHO, Marcio Ramos; MENESCAL-DE-OLIVEIRA, Leda
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
96.35%
Tonic immobility (TI) is an innate defensive behaviour elicited by physical restriction and Postural inversion, and is characterised by a profound and temporary state of akinesis. Our previous studies demonstrated that glutamatergic stimulation of the dorsomedial/dorsolateral Portion of periaqueductal gray matter (dPAG) decreases the duration of TI in guinea pigs (Cavia porcellus). Furthermore, evidence suggests that the anterior cingulate cortex (ACC) constitutes an important Source of glutamate for the dPAG. Hence, in the current study, we investigated the effects of microinjection of the excitatory amino acid (EAA) agonist DL-homocysteic acid (DLH) and the N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 into the ACC on the duration of TI in guinea pigs. We also assessed the effect of the NMDA receptor antagonist (MK-801) into the dorsal periaqueductal gray matter (dPAG) prior to DLH microinjection into the ACC on the TI duration in the guinea pig. Our results demonstrated that DLH microinjections into the ACC decreased the duration of TI. This effect was blocked by previous MK-801 microinjections into the ACC or into the dPAG. The MK-801 microinjections alone did not influence TI duration. These results provide the new insight that EAAs in the ACC can decrease the duration of TI. The mechanism seems to be dependent on the NMDA receptors present in the ACC and in the dPAG. (C) 2009 Elsevier B.V. All rights reserved.; CAPES; FAEPA

Transdural motor cortex stimulation reverses neuropathic pain in rats: A profile of neuronal activation

PAGANO, Rosana L.; ASSIS, Danielle V.; CLARA, Joseph A.; ALVES, Adilson S.; DALE, Camila S.; TEIXEIRA, Manoel J.; FONOFF, Erich T.; BRITTO, Luiz R.
Fonte: ELSEVIER SCI LTD Publicador: ELSEVIER SCI LTD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
76.42%
Motor cortex stimulation (MCS) has been used to treat patients with neuropathic pain resistant to other therapeutic approaches; however, the mechanisms of pain control by MCS are still not clearly understood. We have demonstrated that MCS increases the nociceptive threshold of naive conscious rats, with opioid participation. In the present study, the effect of transdural MCS on neuropathic pain in rats subjected to chronic constriction injury of the sciatic nerve was investigated. In addition, the pattern of neuronal activation, evaluated by Fos and Zif268 immunolabel, was performed in the spinal cord and brain sites associated with the modulation of persistent pain. MCS reversed the mechanical hyperalgesia and allodynia induced by peripheral neuropathy. After stimulation, Fos immunoreactivity (Fos-IR) decreased in the dorsal horn of the spinal cord and in the ventral posterior lateral and medial nuclei of the thalamus, when compared to animals with neuropathic pain. Furthermore, the MCS increased the Fos-IR in the periaqueductal gray, the anterior cingulate cortex and the central and basolateral amygdaloid nuclei. Zif268 results were similar to those obtained for Fos, although no changes were observed for Zif268 in the anterior cingulate cortex and the central amygdaloid nucleus after MCS. The present findings suggest that MCS reverts neuropathic pain phenomena in rats...

Functional and Structural Connectivity Between the Perigenual Anterior Cingulate and Amygdala in Bipolar Disorder

WANG, Fei; KALMAR, Jessica H.; HE, Yong; JACKOWSKI, Marcel; CHEPENIK, Lara G.; EDMISTON, Erin E.; TIE, Karen; GONG, Gaolang; SHAH, Maulik P.; JONES, Monique; UDERMAN, Jodi; CONSTABLE, R. Todd; BLUMBERG, Hilary P.
Fonte: ELSEVIER SCIENCE INC Publicador: ELSEVIER SCIENCE INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
86.35%
Objective: Abnormalities in the morphology and function of two gray matter structures central to emotional processing, the perigenual anterior cingulate cortex (pACC) and amygdala, have consistently been reported in bipolar disorder (BD). Evidence implicates abnormalities in their connectivity in BD. This study investigates the potential disruptions in pACC-amygdala functional connectivity and associated abnormalities in white matter that provides structural connections between the two brain regions in BD. Methods: Thirty-three individuals with BD and 31 healthy comparison subjects (HC) participated in a scanning session during which functional magnetic resonance imaging (fMRI) during processing of face stimuli and diffusion tensor imaging (DTI) were performed. The strength of pACC-amygdala functional connections was compared between BD and HC groups, and associations between these functional connectivity measures from the fMRI scans and regional fractional anisotropy (FA) from the DTI scans were assessed. Results: Functional connectivity was decreased between the pACC and amygdala in the BD group compared with HC group, during the processing of fearful and happy faces (p < .005). Moreover, a significant positive association between pACC-amygdala functional coupling and FA in ventrofrontal white matter...

Risk assessment behaviors associated with corticosterone trigger the defense reaction to social isolation in rats: Role of the anterior cingulate cortex

Reis, Fernando M. C. V.; Albrechet-Souza, Lucas; Franci, Celso R.; Brandao, Marcus L.
Fonte: INFORMA HEALTHCARE; LONDON Publicador: INFORMA HEALTHCARE; LONDON
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
96.38%
The extent to which the hypothalamic-pituitary-adrenal axis is activated by short-term and long-term consequences of stress is still open to investigation. This study aimed to determine (i) the correlation between plasma corticosterone and exploratory behavior exhibited by rats subjected to the elevated plus maze (EPM) following different periods of social isolation, (ii) the effects of the corticosterone synthesis blocker, metyrapone, on the behavioral consequences of isolation, and (iii) whether corticosterone produces its effects through an action on the anterior cingulate cortex, area 1 (Cg1). Rats were subjected to 30-min, 2-h, 24-h, or 7-day isolation periods before EPM exposure and plasma corticosterone assessments. Isolation for longer periods of time produced greater anxiogenic-like effects on the EPM. However, stretched attend posture (SAP) and plasma corticosterone concentrations were increased significantly after 30 min of isolation. Among all of the behavioral categories measured in the EPM, only SAP positively correlated with plasma corticosterone. Metyrapone injected prior to the 24 h isolation period reversed the anxiogenic effects of isolation. Moreover, corticosterone injected into the Cg1 produced a selective increase in SAP. These findings indicate that risk assessment behavior induced by the action of corticosterone on Cg1 neurons initiates a cascade of defensive responses during exposure to stressors.; FAPESP; FAPESP [11/00041-3]; CAPES; CAPES; CNPq; CNPq

Temporal filtering of reward signals in the dorsal anterior cingulate cortex during a mixed-strategy game

Seo, Hyojung; Lee, Daeyeol
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/08/2007 EN
Relevância na Pesquisa
66.58%
The process of decision making in humans and other animals is adaptive and can be tuned through experience so as to optimize the outcomes of their choices in a dynamic environment. Previous studies have demonstrated that the anterior cingulate cortex plays an important role in updating the animal’s behavioral strategies when the action-outcome contingencies change. Moreover, neurons in the anterior cingulate cortex often encode the signals related to expected or actual reward. We investigated whether reward-related activity in the anterior cingulate cortex is affected by the animal’s previous reward history. This was tested in rhesus monkeys trained to make binary choices in a computer-simulated competitive zero-sum game. The animal’s choice behavior was relatively close to the optimal strategy, but also revealed small but systematic biases that are consistent with the use of a reinforcement learning algorithm. In addition, the activity of neurons in the dorsal anterior cingulate cortex that was related to the reward received by the animal in a given trial was often modulated by the rewards in the previous trials. Some of these neurons encoded the rate of rewards in previous trials, whereas others displayed activity modulations more closely related to the reward prediction errors. By contrast...

Cytology and Receptor Architecture of Human Anterior Cingulate Cortex

Palomero-Gallagher, Nicola; Mohlberg, Hartmut; Zilles, Karl; Vogt, Brent A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 20/06/2008 EN
Relevância na Pesquisa
66.45%
Anterior cingulate cortex (ACC) is involved in emotion, emotional expression, mood and autonomic regulation in contrast to midcingulate cortex, which regulates response selection via cognitive and skeletomotor mechanisms. Although a subgenual part of ACC (sACC) may be vulnerable in depression and area 25 is cytologically unique, there are no assessments that contrast this region to pregenual ACC (pACC); both include parts of areas 32, 24, and 33 and the cingulate sulcus extends rostral to the corpus callosum and might contain area 24c. Independent verifications of cytoarchitectural differences among subregions, areas and laminar binding was undertaken with an observer-interactive approach and multireceptor autoradiography. Areas 24a and 24b have pregenual (p24a, p24b) and subgenual (s24a, s24b) components and subgenual areas have a very thin layer III. Area 24c is rostral to the genu (p24c) and has dorsal (pd24c) and ventral (pv24c) parts. Area pd24c has more and larger neurofilament-expressing neurons in layer Va and neurons in Vb form aggregates in area pv24c rather than solitary pyramids as in pd24c. Area pd24c occupies both banks of the cingulate sulcus with pv24c on the ventral bank. Layer III distinguishes these areas with pd24cd having many larger neurofilament-expressing neurons and a richer dendritic plexus in the entire layer III. Area 32 has pregenual (p32) and subgenual (s32) components. Layer II in s32 is of particular note because it has a neuron dense IIa and sparse IIb. Area 25 is comprised of anterior (25a) and posterior (25p) parts; 25p has the thinnest layer III in the cingulate gyrus and larger and more dense neurons in layer II. Area 33 continues around the genu and ventrally to encompass the full caudal extent of area 25. The multivariate...

Differential alterations of kainate receptor subunits in inhibitory interneurons in the anterior cingulate cortex in schizophrenia and bipolar disorder

Woo, Tsung-Ung W.; Shrestha, Kevin; Amstrong, Christopher; Minns, Martin M.; Walsh, John P.; Benes, Francine M.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
66.46%
The aim of this study was to examine whether glutamatergic inputs onto GABA interneurons via the kainate receptor in the anterior cingulate cortex may be altered in schizophrenia and bipolar disorder. Hence, in a cohort of 60 post-mortem human brains from schizophrenia, bipolar disorder, and normal control subjects, we simultaneously labeled the mRNA for the GluR5 or GluR6 subunit of the kainate receptor with [35S] and the mRNA for the 67 kD isoform of the GABA synthesizing enzyme glutamic acid decarboxylase (GAD)67 with digoxigenin using an immunoperoxidase method. The density of the GAD67 mRNA-containing neurons that co-expressed GluR5 mRNA was decreased by 43% and 40% in layer 2 of the anterior cingulate cortex in schizophrenia and bipolar disorder, respectively. In contrast, the density of the GAD67 mRNA-containing cells that expressed GluR6 mRNA was unaltered in either condition. Furthermore, the amount of GluR5 or GluR6 mRNA in the GAD67 mRNA-expressing cells that contained a detectable level of these transcripts was also unchanged. Finally, the density of cells that did not contain GAD67 mRNA, which presumably included all pyramidal neurons, but expressed the mRNA for the GluR5 or GluR6 subunit was not altered. Thus, glutamatergic modulation of inhibitory interneurons...

Preparatory Activity and Connectivity in Dorsal Anterior Cingulate Cortex for Cognitive Control

Schulz, Kurt P.; Bédard, Anne-Claude V.; Czarnecki, Rosa; Fan, Jin
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
66.48%
Dorsal anterior cingulate cortex (dACC) is composed of functionally distinct subregions that may contribute to the top-down control of response selection and preparation. Multiple motor areas have been identified in dACC, including an anterior zone implicated in conflict monitoring and a caudal zone involved in movement execution. This study tested the involvement of a third cingulate area, the posterior zone of dACC, in the top-down control of response selection and preparation. Sixteen healthy young adults were scanned with event-related functional magnetic resonance imaging while performing a cued go/no-go task that was designed to minimize response conflicts. The activation and functional connectivity of dACC were tested with standard convolution models and psychophysiological interaction analyses, respectively. Ready cues that informed the direction of the impending response triggered preparatory neural activity in the posterior zone of dACC and strengthened functional connectivity with the anterior and caudal zones of dACC, as well as perigenual anterior cingulate cortex, frontal operculum, dorsolateral prefrontal cortex, sensory association cortices, and extra-pyramidal motor areas. The preparatory cues activated dACC above and beyond the general arousing effects common to cues despite negligible conflict in the go/no-go task. The integration of cognitive...

Attentional effects of lesions to the anterior cingulate cortex: how prior reinforcement influences distractibility

Newman, Lori A.; McGaughy, Jill
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/2011 EN
Relevância na Pesquisa
66.62%
Morphological changes in the anterior cingulate cortex are found in subjects with schizophrenia, attention deficit hyperactivity disorder, and obsessive compulsive disorder. These changes are hypothesized to underlie the impairments these individuals show on tasks that require cognitive control. The anterior cingulate cortex has previously been shown to be active in situations involving high conflict, presentation of salient, distracting stimuli, and error processing, i.e. situations that occur when a shift in attention or responding is required. However, there is some uncertainty as to what specific role the anterior cingulate cortex plays in these situations. The current study used converging evidence from two behavioral paradigms to determine the effects of excitotoxic lesions in the anterior cingulate cortex on executive control. The first assay tests reversal learning, attentional set formation and shifting. The second assesses sustained attention with and without distractors. Animals with anterior cingulate cortex lesions were impaired during reinforcement reversals, discriminations that required subjects to disregard previously relevant stimulus attributes and showed a more rapid decline in attentional ability than Sham-Lx subjects when maintaining sustained attention for extended periods of time. These results are consistent with the hypothesis that the anterior cingulate cortex is involved in attending to stimulus attributes that currently predict reinforcement in the presence of previously relevant...

Increased glutamate levels observed upon functional activation in the anterior cingulate cortex using the Stroop Task and functional spectroscopy

Taylor, Reggie; Schaefer, Betsy; Densmore, Maria; Neufeld, Richard W.J.; Rajakumar, Nagalingam; Williamson, Peter C.; Théberge, Jean
Fonte: Lippincott Williams & Wilkins Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
66.48%
It has been shown in recent studies that it is possible to detect changes in the main excitatory neurotransmitter, glutamate, upon functional activation with visual and motor paradigms using a 7 T MRI and functional magnetic resonance spectroscopy. A cognitive task would be desirable for this technique because it could then be used to examine psychiatric disorders that have cognitive deficiencies. The aim of the work presented here was to use functional magnetic resonance spectroscopy with a 7 T MRI to show that increases in glutamate can be observed within the anterior cingulate cortex using the Stroop Task as the activation paradigm in healthy controls. Significant glutamate increases (0.24±0.09 µmol/g, P<0.025), comparable with what has been reported in the studies of the occipital cortex and motor cortex, were observed when the participants (n=7) performed the task, followed by a trend toward returning to baseline in the post-task recovery period (−0.23±0.13 µmol/g). This method would be ideal for the study of neuropsychiatric disorders that have been shown to have abnormal resting glutamate levels and cognitive deficiencies in the anterior cingulate cortex, such as schizophrenia. This exploratory study is the first to demonstrate functional magnetic resonance spectroscopy in the anterior cingulate with a cognitive task using a 7 T MRI.

Response Monitoring, Repetitive Behaviour and Anterior Cingulate Abnormalities in Autism Spectrum Disorders (ASD)

Thakkar, Katharine N.; Tuch, David S.; Barton, Jason J.S.; Polli, Frida E.; Joseph, Robert Michael; Hadjikhani, Nouchine; Manoach, Dara S
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
86.3%
Autism spectrum disorders (ASD) are characterized by inflexible and repetitive behaviour. Response monitoring involves evaluating the consequences of behaviour and making adjustments to optimize outcomes. Deficiencies in this function, and abnormalities in the anterior cingulate cortex (ACC) on which it relies, have been reported as contributing factors to autistic disorders. We investigated whether ACC structure and function during response monitoring were associated with repetitive behaviour in ASD. We compared ACC activation to correct and erroneous antisaccades using rapid presentation event-related functional MRI in 14 control and ten ASD participants. Because response monitoring is the product of coordinated activity in ACC networks, we also examined the microstructural integrity of the white matter (WM) underlying this brain region using diffusion tensor imaging (DTI) measures of fractional anisotropy (FA) in 12 control and 12 adult ASD participants. ACC activation and FA were examined in relation to Autism Diagnostic Interview-Revised ratings of restricted and repetitive behaviour. Relative to controls, ASD participants: (i) made more antisaccade errors and responded more quickly on correct trials; (ii) showed reduced discrimination between error and correct responses in rostral ACC (rACC)...

Epileptiform Synchronization of the Anterior Cingulate Cortex of the Rat and its Modulation by Mu-Opioid Receptor

PANUCCIO, GABRIELLA
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
96.66%
Over the past century, the cingulate cortex has been catching the interest of both basic science and clinical research in various fields of investigation due to its involvement in several physiological functions. This brain region can in fact modulate affection and behavior, motor responses and autonomic functions, and it has been implicated in the pathophysiology of psychiatric disorders and epilepsy. The relevance of considering seizures arising from the cingulate gyrus as a distinct neurological entity has been considered in light of the capability of this brain region to directly affect the functional balance of a more extensive system, involving frontal and temporal areas. The term “cingulate epilepsy” identifies a chronic neurological syndrome, which can be distinguished from other epileptic conditions by its peculiar clinical manifestations. The anterior cingulate cortex presents with a high density of opioid receptors, which account for the involvement of this cortical area in pain perception. Nonetheless, opioid receptors may be relevant to epilepsy as well, providing their contribution as modulators of cortical activity. However, whether opioid receptors exert a pro- or an anti-convulsant effect is still matter of debate. In light of the high expression of opioid receptors...

Early life stress and morphometry of the adult anterior cingulate cortex and caudate nuclei

Cohen, R.; Grieve, S.; Hoth, K.; Paul, R.; Sweet, L.; Tate, D.; Gunstad, J.; Stroud, L.; McCaffery, J.; Hitsman, B.; Niaura, R.; Clark, C.; McFarlane, A.; Bryant, R.; Gordon, E.; Williams, L.
Fonte: Elsevier Science Inc Publicador: Elsevier Science Inc
Tipo: Artigo de Revista Científica
Publicado em //2006 EN
Relevância na Pesquisa
96.35%
Background Early life stress (ELS) is linked to adult psychopathology and may contribute to long-term brain alterations, as suggested by studies of women who suffered childhood sexual abuse. We examine whether reported adverse ELS defined as stressful and/or traumatic adverse childhood events (ACEs) is associated with smaller limbic and basal ganglia volumes. Method 265 healthy Australian men and women without psychopathology or brain disorders were studied. ACEs were assessed by the ELSQ and current emotional state by the DASS. Anterior cingulate cortex (ACC), hippocampus, amygdala, and caudate nucleus volumes were measured from T1-weighted MRI. Analyses examined ROI volumetric associations with reported ACEs and DASS scores. Results Participants with greater than two ACEs had smaller ACC and caudate nuclei than those without ACEs. A significant association between total ACEs and ROI volumes for these structures was observed. Regression analysis also revealed that ELS was more strongly associated than current emotional state (DASS) with these ROI volumes. Conclusions Reported ELS is associated with smaller ACC and caudate volumes, but not the hippocampal or amygdala volumes. The reasons for these brain effects are not entirely clear...

The Role of the Nucleus Accumbens and Rostral Anterior Cingulate Cortex in Anhedonia: Integration of Resting EEG, fMRI, and Volumetric Techniques

Wacker, Jan; Pizzagalli, Diego A; Dillon, Daniel G.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
96.35%
Anhedonia, the reduced propensity to experience pleasure, is a promising endo-- phenotype and vulnerability factor for several psychiatric disorders, including depression and schizophrenia. In the present study, we used resting electroencephalography, functional magnetic resonance imaging, and volumetric analyses to probe putative associations between anhedonia and individual differences in key nodes of the brain's reward system in a non-clinical sample. We found that anhedonia, but not other symptoms of depression or anxiety, was correlated with reduced nucleus accumbens (NAcc) responses to rewards (gains in a monetary incentive delay task), reduced NAcc volume, and increased resting delta current density (i.e., decreased resting activity) in the rostral anterior cingulate cortex (rACC), an area previously implicated in positive subjective experience. In addition, NAcc reward responses were inversely associated with rACC resting delta activity, supporting the hypothesis that delta might be lawfully related to activity within the brain's reward circuit. Taken together, these results help elucidate the neural basis of anhedonia and strengthen the argument for anhedonia as an endophenotype for depression.; Psychology

The von Economo neurons in frontoinsular and anterior cingulate cortex in great apes and humans

Allman, John M.; Tetreault, Nicole A.; Hakeem, Atiya Y.; Manaye, Kebreten F.; Semendeferi, Katerina; Erwin, Joseph M.; Park, Soyoung; Goubert, Virginie; Hof, Patrick R.
Fonte: Springer Publicador: Springer
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em /06/2010
Relevância na Pesquisa
66.48%
The von Economo neurons (VENs) are large bipolar neurons located in frontoinsular (FI) and anterior cingulate cortex in great apes and humans, but not other primates. We performed stereological counts of the VENs in FI and LA (limbic anterior, a component of anterior cingulate cortex) in great apes and in humans. The VENs are more numerous in humans than in apes, although one gorilla approached the lower end of the human range. We also examined the ontological development of the VENs in FI and LA in humans. The VENs first appear in small numbers in the 36th week post-conception, are rare at birth, and increase in number during the first 8 months after birth. There are significantly more VENs in the right hemisphere than in the left in FI and LA in postnatal brains of apes and humans. This asymmetry in VEN numbers may be related to asymmetries in the autonomic nervous system. The activity of the inferior anterior insula, which contains FI, is related to physiological changes in the body, decision-making, error recognition, and awareness. The VENs appear to be projection neurons, although their targets are unknown. We made a preliminary study of the connections of FI cortex based on diffusion tensor imaging in the brain of a gorilla. The VEN-containing regions connect to the frontal pole as well as to other parts of frontal and insular cortex...

A parametric assessment of GABA antagonist effects on paired-pulse facilitation in the rat anterior cingulate cortex

Sylantyev, Sergiy; Lee, Chia-Ming; Shyu, Bai-Chuang
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
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Paired-pulse facilitation (PPF) is a form of short-term plasticity that can be used qualitatively to characterize the synaptic effects of neuroactive compounds. As we have shown previously, CNQX has a marked effect on PPF which can be measured quantitatively. The aim of the present study was to examine quantitatively possible differences in the effects of the post- and pre-synaptic GABA antagonists on PPF in vitro. Experiments were performed on slices taken from the coronal anterior cingulate cortex (ACC) of Sprague-Dawley rats. The stimuli consisted of a pair of biphasic pulses with an inter-pulse interval of 40 ms. Evoked extracellular field potentials in layers 2/3 of the ACC were recorded. Quantitative assessment of PPF was achieved by calculating two parameters, the PPFmax (theoretical maximal PPF) and the St max (stimulus intensity that produces the PPFmax). Picrotoxin treatment produced increases in both the PPFmax and Stmax, by increasing the stimulus producing the half-maximal effect. In contrast, CGP-55845 treatment produced an increase in only the PPF max, which was due to an alteration in the asymptotic values of the response amplitudes. Our findings show that the effect of different GABA receptor antagonists on short-term synaptic facilitation in the ACC may be assessed and specified quantitatively.