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Xindao Yin - One of the best experts on this subject based on the ideXlab platform.

  • Altered lateral geniculate nucleus functional connectivity in migraine without aura: a resting-state functional MRI study.
    The journal of headache and pain, 2020
    Co-Authors: Di Zhang, Xiaobin Huang, Yu-chen Chen, Peng Wang, Cunnan Mao, Zhengfei Miao, Chunmei Liu, Xindao Yin
    Abstract:

    Objectives To investigate the structural and functional connectivity changes of lateral geniculate nucleus (LGN) and their relationships with clinical characteristics in patients without aura. Methods Conventional MRI, 3D structure images and resting state functional MRI were performed in 30 migraine patients without aura (MwoA) and 22 healthy controls (HC). The lateral geniculate nucleus volumes and the functional connectivity (FC) of bilateral lateral geniculate nucleus were computed and compared between groups. Results The lateral geniculate nucleus volumes in patient groups did not differ from the controls. The brain regions with increased FC of the left LGN mainly located in the left cerebellum and right Lingual Gyrus in MwoA compared with HC. The increased FC of right LGN located in left inferior frontal Gyrus in MwoA compared with HC. The correlation analysis showed a positive correlation between VLSQ-8 score and the increased FC of left cerebellum and right Lingual Gyrus. Conclusions Photophobia in MwoA could be mediated by abnormal resting state functional connectivity in visual processing regions, the pain perception regulatory network and emotion regulation network. This result is valuable to further understanding about the clinical manifestation and pathogenesis of migraine.

  • Amygdala functional disconnection with the prefrontal-cingulate-temporal circuit in chronic tinnitus patients with depressive mood.
    Progress in neuro-psychopharmacology & biological psychiatry, 2017
    Co-Authors: Yu-chen Chen, Peng Wang, Wenqing Xia, Shenghua Liu, Zhenyu Xiong, Xindao Yin
    Abstract:

    Abstract Chronic tinnitus is often accompanied with depressive symptom, which may arise from aberrant functional coupling between the amygdala and cerebral cortex. To explore this hypothesis, resting-state functional magnetic resonance imaging (fMRI) was used to investigate the disrupted amygdala-cortical functional connectivity (FC) in chronic tinnitus patients with depressive mood. Chronic tinnitus patients with depressive mood ( n  = 20), without depressive mood ( n  = 20), and well-matched healthy controls ( n  = 23) underwent resting-state fMRI scanning. Amygdala-cortical FC was characterized using a seed-based whole-brain correlation method. The bilateral amygdala FC was compared among the three groups. Compared to non-depressed patients, depressive tinnitus patients showed decreased amygdala FC with the prefrontal cortex and anterior cingulate cortex as well as increased amygdala FC with the postcentral Gyrus and Lingual Gyrus. Relative to healthy controls, depressive tinnitus patients revealed decreased amygdala FC with the superior and middle temporal Gyrus, anterior and posterior cingulate cortex, and prefrontal cortex, as well as increased amygdala FC with the postcentral Gyrus and Lingual Gyrus. The current study identified for the first time abnormal resting-state amygdala-cortical FC with the prefrontal-cingulate-temporal circuit in chronic tinnitus patients with depressive mood, which will provide novel insight into the underlying neuropathological mechanisms of tinnitus-induced depressive disorder.

Andreas Frick - One of the best experts on this subject based on the ideXlab platform.

  • Enlargement of visual processing regions in social anxiety disorder is related to symptom severity.
    Neuroscience letters, 2014
    Co-Authors: Andreas Frick, Jonas Engman, Iman Alaie, Johannes Björkstrand, Vanda Faria, Malin Gingnell, Ulrika Wallenquist, Kurt Wahlstedt, Thomas Ågren, Elna-marie Larsson
    Abstract:

    Social anxiety disorder (SAD) is associated with altered brain function and structure, but most structural studies include small samples and findings are mixed. This study compared regional gray matter volume between 48 SAD patients and 29 healthy controls (HC) as well as the relationship between volume and symptom severity. Structural magnetic resonance images from SAD patients and HC were evaluated using standard voxel-based morphometry (VBM) processing in the SPM8 software package. Social anxiety symptom severity was rated in SAD patients by a clinician using the Liebowitz Social Anxiety Scale (LSAS). SAD patients had greater regional gray matter volume in the Lingual Gyrus and lateral occipital cortex than the controls, and within the SAD group a positive correlation was found between symptom severity and regional gray matter volume in the Lingual Gyrus and the retrosplenial cortex. These findings replicate and extend earlier reports of enlarged visual processing areas in SAD. Increased gray matter volume in regions involved in visual processing and self-consciousness could underlie, or be the result of, abnormal emotional information processing and self-focused attention previously demonstrated in patients with SAD.

  • Regional Gray Matter Volume of the Lingual Gyrus is Related to Symptom Severity in Patients with Social Anxiety Disorder
    Biological Psychiatry, 2013
    Co-Authors: Andreas Frick, Jonas Engman, Iman Alaie, Johannes Björkstrand, Vanda Faria, Malin Gingnell, Ulrika Wallenquist, Kurt Wahlstedt, Mats Fredrikson, Tomas Furmark
    Abstract:

    Regional Gray Matter Volume of the Lingual Gyrus is Related to Symptom Severity in Patients with Social Anxiety Disorder

G. E. Cold - One of the best experts on this subject based on the ideXlab platform.

  • Regional cerebral glucose metabolism during sevoflurane anaesthesia in healthy subjects studied with positron emission tomography.
    Acta anaesthesiologica Scandinavica, 2010
    Co-Authors: Lise Schlünzen, Albert Gjedde, Niels Juul, K. Hansen, G. E. Cold
    Abstract:

    Background: The precise mechanism by which sevoflurane exerts its effects in the human brain remains unknown. In the present study, we quantified the effects of sevoflurane on regional cerebral glucose metabolism (rGMR) in the human brain measured with positron emission tomography. Methods: Eight volunteers underwent two dynamic 18F-fluorodeoxyglucose positron emission tomography (PET) scans. One scan assessed conscious-baseline metabolism and the other scan assessed metabolism during 1 minimum alveolar concentration (MAC) sevoflurane anaesthesia. Cardiovascular and respiratory parameters were monitored and bispectral index responses were registered. Statistical parametric maps and conventional regions of interest analysis were used to determine rGMR differences. Results: All subjects were unconsciousness at 1.0 MAC sevoflurane. Cardiovascular and respiratory parameters were constant over time. In the awake state, rGMR ranged from 0.24 to 0.35 μmol/g/min in the selected regions. Compared with the conscious state, total GMR decreased 56% in sevoflurane anaesthesia. In white and grey matter, GMR was averaged 42% and 58% of normal, respectively. Sevoflurane reduced the absolute rGMR in all selected areas by 48–71% of the baseline (P≤0.01), with the most significant reductions in the Lingual Gyrus (71%), occipital lobe in general (68%) and thalamus (63%). No increases in rGMR were observed. Conclusions: Sevoflurane caused a global whole-brain metabolic reduction of GMR in all regions of the human brain, with the most marked metabolic suppression in the Lingual Gyrus, thalamus and occipital lobe.

  • Effects of dose-dependent levels of isoflurane on cerebral blood flow in healthy subjects studied using positron emission tomography.
    Acta anaesthesiologica Scandinavica, 2006
    Co-Authors: Lise Schlünzen, G. E. Cold, Mads Rasmussen, Manouchehr Seyedi Vafaee
    Abstract:

    Background:  In this study, we tested the hypothesis that escalating drug concentrations of isoflurane are associated with a significant decline in cerebral blood flow (CBF) in regions sub-serving conscious brain activity, including specifically the thalamus. Methods:  Nine human volunteers received three escalating drug concentrations: 0.2, 0.4 and 1.0 MAC end-tidal inhalation. During waking, baseline and the three levels of sedation, aO PET scan was performed. Results:  Isoflurane decreased the bispectral index (BIS) values dose-dependently. Cardiovascular and respiratory parameters were maintained constant over time. No significant change in global CBF was observed. Throughout all three MAC levels of sedation, isoflurane caused an increased regional cerebral blood flow (rCBF) in the anterior cingulate and decreased rCBF in the cerebellum. Initially, isoflurane (0 vs. 0.2 MAC) significantly increased relative rCBF in the medial frontal Gyrus and in the nucleus accumbens. At the next level (0.2 vs. 0.4 MAC), relative rCBF was significantly increased in the caudate nucleus and decreased in the Lingual Gyrus and cuneus. At the last level (0.4 vs. 1 MAC), relative rCBF was significantly increased in the insula and decreased in the thalamus, the cuneus and Lingual Gyrus. Compared with flow distribution in awake volunteers, 1 MAC of isoflurane significantly raised relative activity in the anterior cingulate and insula regions. In contrast, a significant relative flow reduction was identified in the thalamus, the cerebellum and Lingual Gyrus. Conclusions:  Isoflurane, like sevoflurane, induced characteristic flow redistribution at doses of 0.2–1.0 MAC. At 1 MAC of isoflurane, rCBF decreased in the thalamus. Specific areas affected by both isoflurane and sevoflurane included the anterior cingulate, insula regions, cerebellum, Lingual Gyrus and thalamus.

  • Effects of subanaesthetic and anaesthetic doses of sevoflurane on regional cerebral blood flow in healthy volunteers. A positron emission tomographic study.
    Acta anaesthesiologica Scandinavica, 2004
    Co-Authors: Lise Schlünzen, G. E. Cold, Mads Rasmussen, Manouchehr Seyedi Vafaee, Jørgen Feldbæk Nielsen, Albert Gjedde
    Abstract:

    Background:  We tested the hypothesis that escalating drug concentrations of sevoflurane are associated with a significant decline of cerebral blood flow in regions subserving conscious brain activity, including specifically the thalamus. Methods:  Nine healthy human volunteers received three escalating doses using 0.4%, 0.7% and 2.0% end-tidal sevoflurane inhalation. During baseline and each of the three levels of anaesthesia one PET scan was performed after injection of . Cardiovascular and respiratory parameters were monitored and electroencephalography and bispectral index (BIS) were registered. Results:  Sevoflurane decreased the BIS values dose-dependently. No significant change in global cerebral blood flow (CBF) was observed. Increased regional CBF (rCBF) in the anterior cingulate (17–21%) and decreased rCBF in the cerebellum (18–35%) were identified at all three levels of sedation compared to baseline. Comparison between adjacent levels sevoflurane initially (0 vs. 0.2 MAC) decreased rCBF significantly in the inferior temporal cortex and the Lingual Gyrus. At the next level (0.2 MAC vs. 0.4 MAC) rCBF was increased in the middle temporal cortex and in the Lingual Gyrus, and decreased in the thalamus. At the last level (0.4 MAC vs. 1 MAC) the rCBF was increased in the insula and decreased in the posterior cingulate, the Lingual Gyrus, precuneus and in the frontal cortex. Conclusion:  At sevoflurane concentrations at 0.7% and 2.0% a significant decrease in relative rCBF was detected in the thalamus. Interestingly, some of the most profound changes in rCBF were observed in structures related to pain processing (anterior cingulate and insula).

Lise Schlünzen - One of the best experts on this subject based on the ideXlab platform.

  • Regional cerebral glucose metabolism during sevoflurane anaesthesia in healthy subjects studied with positron emission tomography.
    Acta anaesthesiologica Scandinavica, 2010
    Co-Authors: Lise Schlünzen, Albert Gjedde, Niels Juul, K. Hansen, G. E. Cold
    Abstract:

    Background: The precise mechanism by which sevoflurane exerts its effects in the human brain remains unknown. In the present study, we quantified the effects of sevoflurane on regional cerebral glucose metabolism (rGMR) in the human brain measured with positron emission tomography. Methods: Eight volunteers underwent two dynamic 18F-fluorodeoxyglucose positron emission tomography (PET) scans. One scan assessed conscious-baseline metabolism and the other scan assessed metabolism during 1 minimum alveolar concentration (MAC) sevoflurane anaesthesia. Cardiovascular and respiratory parameters were monitored and bispectral index responses were registered. Statistical parametric maps and conventional regions of interest analysis were used to determine rGMR differences. Results: All subjects were unconsciousness at 1.0 MAC sevoflurane. Cardiovascular and respiratory parameters were constant over time. In the awake state, rGMR ranged from 0.24 to 0.35 μmol/g/min in the selected regions. Compared with the conscious state, total GMR decreased 56% in sevoflurane anaesthesia. In white and grey matter, GMR was averaged 42% and 58% of normal, respectively. Sevoflurane reduced the absolute rGMR in all selected areas by 48–71% of the baseline (P≤0.01), with the most significant reductions in the Lingual Gyrus (71%), occipital lobe in general (68%) and thalamus (63%). No increases in rGMR were observed. Conclusions: Sevoflurane caused a global whole-brain metabolic reduction of GMR in all regions of the human brain, with the most marked metabolic suppression in the Lingual Gyrus, thalamus and occipital lobe.

  • Effects of dose-dependent levels of isoflurane on cerebral blood flow in healthy subjects studied using positron emission tomography.
    Acta anaesthesiologica Scandinavica, 2006
    Co-Authors: Lise Schlünzen, G. E. Cold, Mads Rasmussen, Manouchehr Seyedi Vafaee
    Abstract:

    Background:  In this study, we tested the hypothesis that escalating drug concentrations of isoflurane are associated with a significant decline in cerebral blood flow (CBF) in regions sub-serving conscious brain activity, including specifically the thalamus. Methods:  Nine human volunteers received three escalating drug concentrations: 0.2, 0.4 and 1.0 MAC end-tidal inhalation. During waking, baseline and the three levels of sedation, aO PET scan was performed. Results:  Isoflurane decreased the bispectral index (BIS) values dose-dependently. Cardiovascular and respiratory parameters were maintained constant over time. No significant change in global CBF was observed. Throughout all three MAC levels of sedation, isoflurane caused an increased regional cerebral blood flow (rCBF) in the anterior cingulate and decreased rCBF in the cerebellum. Initially, isoflurane (0 vs. 0.2 MAC) significantly increased relative rCBF in the medial frontal Gyrus and in the nucleus accumbens. At the next level (0.2 vs. 0.4 MAC), relative rCBF was significantly increased in the caudate nucleus and decreased in the Lingual Gyrus and cuneus. At the last level (0.4 vs. 1 MAC), relative rCBF was significantly increased in the insula and decreased in the thalamus, the cuneus and Lingual Gyrus. Compared with flow distribution in awake volunteers, 1 MAC of isoflurane significantly raised relative activity in the anterior cingulate and insula regions. In contrast, a significant relative flow reduction was identified in the thalamus, the cerebellum and Lingual Gyrus. Conclusions:  Isoflurane, like sevoflurane, induced characteristic flow redistribution at doses of 0.2–1.0 MAC. At 1 MAC of isoflurane, rCBF decreased in the thalamus. Specific areas affected by both isoflurane and sevoflurane included the anterior cingulate, insula regions, cerebellum, Lingual Gyrus and thalamus.

  • Effects of subanaesthetic and anaesthetic doses of sevoflurane on regional cerebral blood flow in healthy volunteers. A positron emission tomographic study.
    Acta anaesthesiologica Scandinavica, 2004
    Co-Authors: Lise Schlünzen, G. E. Cold, Mads Rasmussen, Manouchehr Seyedi Vafaee, Jørgen Feldbæk Nielsen, Albert Gjedde
    Abstract:

    Background:  We tested the hypothesis that escalating drug concentrations of sevoflurane are associated with a significant decline of cerebral blood flow in regions subserving conscious brain activity, including specifically the thalamus. Methods:  Nine healthy human volunteers received three escalating doses using 0.4%, 0.7% and 2.0% end-tidal sevoflurane inhalation. During baseline and each of the three levels of anaesthesia one PET scan was performed after injection of . Cardiovascular and respiratory parameters were monitored and electroencephalography and bispectral index (BIS) were registered. Results:  Sevoflurane decreased the BIS values dose-dependently. No significant change in global cerebral blood flow (CBF) was observed. Increased regional CBF (rCBF) in the anterior cingulate (17–21%) and decreased rCBF in the cerebellum (18–35%) were identified at all three levels of sedation compared to baseline. Comparison between adjacent levels sevoflurane initially (0 vs. 0.2 MAC) decreased rCBF significantly in the inferior temporal cortex and the Lingual Gyrus. At the next level (0.2 MAC vs. 0.4 MAC) rCBF was increased in the middle temporal cortex and in the Lingual Gyrus, and decreased in the thalamus. At the last level (0.4 MAC vs. 1 MAC) the rCBF was increased in the insula and decreased in the posterior cingulate, the Lingual Gyrus, precuneus and in the frontal cortex. Conclusion:  At sevoflurane concentrations at 0.7% and 2.0% a significant decrease in relative rCBF was detected in the thalamus. Interestingly, some of the most profound changes in rCBF were observed in structures related to pain processing (anterior cingulate and insula).

Tomas Furmark - One of the best experts on this subject based on the ideXlab platform.