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1.
Neuroimage ; 265: 119812, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36526104

RESUMO

Increasing time spent on the task (i.e., the time-on-task (ToT) effect) often results in mental fatigue. Typical effects of ToT are decreasing levels of task-related motivation and the deterioration of cognitive performance. However, a massive body of research indicates that the detrimental effects can be reversed by extrinsic motivators, for example, providing rewards to fatigued participants. Although several attempts have been made to identify brain areas involved in mental fatigue and related reward processing, the neural correlates are still less understood. In this study, we used the psychomotor vigilance task to induce mental fatigue and blood oxygen-level-dependent functional magnetic resonance imaging to investigate the neural correlates of the ToT effect and the reward effect (i.e., providing extra monetary reward after fatigue induction) in a healthy young sample. Our results were interpreted in a recently proposed neurocognitive framework. The activation of the right middle frontal gyrus, right insula and right anterior cingulate gyrus decreased as fatigue emerged and the cognitive performance dropped. However, after providing an extra reward, the cognitive performance, as well as activation of these areas, increased. Moreover, the activation levels of all of the mentioned areas were negatively associated with reaction times. Our results confirm that the middle frontal gyrus, insula and anterior cingulate cortex play crucial roles in cost-benefit evaluations, a potential background mechanism underlying fatigue, as suggested by the neurocognitive framework.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/fisiologia , Motivação , Mapeamento Encefálico/métodos , Recompensa , Fadiga Mental/diagnóstico por imagem
2.
J Magn Reson Imaging ; 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37602529

RESUMO

BACKGROUND: Although COVID-19 is primarily an acute respiratory infection, 5%-40% of patients develop late and prolonged symptoms with frequent neurological complaints, known as long COVID syndrome. The presentation of the disease suggests that COVID infection may cause functional and/or morphological central nervous system alterations, but studies published in the literature report contradictory findings. PURPOSE: To investigate the chronic effects of COVID-19 on cerebral grey matter in a group of young patients without comorbidities, with mild course of COVID infection and no medical complaints at the time of examination. STUDY TYPE: Prospective. POPULATION: Thirty-eight young (age = 26.6 ± 5.0 years; male/female = 14/24), adult participants who recovered from mild COVID infection without a history of clinical long COVID and 37 healthy control subjects (age = 25.9 ± 2.8 years; male/female = 14/23). FIELD STRENGTH/SEQUENCE: Three Tesla, 3D T1-weighted magnetization-prepared rapid gradient-echo, 2D T2-weighted turbo spin-echo. ASSESSMENT: MRI-based morphometry and volumetry along with neuropsychological testing and self-assessed questionnaire. STATISTICAL TESTS: Fisher's exact test, Mann-Whitney U-test, and multiple linear regression analyses were used to assess differences between COVID and healthy control groups. P < 0.05 was used as cutoff for significance. RESULTS: In the COVID group, significantly lower bilateral mean cortical thickness (left/right-hemisphere: 2.51 ± 0.06 mm vs. 2.56 ± 0.07 mm, η2 p = 0.102/2.50 ± 0.06 mm vs. 2.54 ± 0.07 mm, η2 p = 0.101), lower subcortical gray matter (57881 ± 3998 mm3 vs. 60470 ± 5211 mm3 , η2 p = 0.100) and lower right olfactory bulb volume (52.28 ± 13.55 mm3 vs. 60.98 ± 15.8 mm3 , η2 p = 0.078) were found. In patients with moderate to severe anosmia, cortical thickness was significantly lower bilaterally, as compared to patients without olfactory function loss (left/right-hemisphere: 2.50 ± 0.06 mm vs. 2.56 ± 0.05 mm, η2 = 0.173/2.49 ± 0.06 mm vs. 2.55 ± 0.05 mm, η2 = 0.189). Using further exploratory analysis, significantly reduced cortical thickness was detected locally in the right lateral orbitofrontal cortex in the COVID group (2.53 ± 0.10 mm vs. 2.60 ± 0.09 mm, η2 p = 0.112). DATA CONCLUSION: Even without any subjective or objective neurological complaints at the time of the MR scan, subjects in the COVID group showed gray matter alterations in cortical thickness and subcortical gray matter volume. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 3.

3.
Acta Neurochir (Wien) ; 163(7): 1941-1947, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33821318

RESUMO

Neglect is a severe neuropsychological/neurological deficit that usually develops due to lesions of the posterior inferior parietal area of the right hemisphere and is characterized by a lack of attention to the left side. Our case is a proven right-handed, 30-year-old female patient with a low-grade glioma, which was located in the temporo-opercular region and also in the superior temporal gyrus of the right hemisphere. Upon presurgical planning, the motor, language, and visuospatial functions were mapped. In order to achieve this, the protocol for routine magnetic resonance imaging and navigated transcranial magnetic stimulation has been expanded, accordingly.


Assuntos
Neoplasias Encefálicas , Glioma , Vigília , Adulto , Mapeamento Encefálico , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Córtex Cerebral , Feminino , Glioma/diagnóstico por imagem , Glioma/cirurgia , Humanos , Estimulação Magnética Transcraniana
4.
J Headache Pain ; 20(1): 4, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30630410

RESUMO

BACKGROUND/AIM: Migraine-related intracerebral white matter lesions (WMLs) are likely to be microvascular in nature and can be found in all hemispheric lobes. The aim of this study was to investigate migraine patients with or without WMLs to see the effects of these tissue damages on cortical thickness and volume. The role of migraine characteristics (duration of headache, attack frequency, estimated lifetime attack number, aura) was also tested. METHODS: As study participants, 161 female migraine patients (63 with aura; 52 with WMLs) and 40 age-matched healthy female subjects were enrolled in the study. None of the included migraine patients' headache or aura (where present) was unilaterally side-locked. Patients and controls were all right handed. Except for migraine, patients were free of any medical comorbidity. Cortical reconstruction and segmentation were performed on the 3D T1-weighted images using Freesurfer 5.3 image analysis suite. The automatic cortical parcellation was based on Freesurfer's Desikan-Killiany-Tourville atlas, which has 31 cortical regions per hemisphere. The segmented regions were divided into five lobes (frontal, parietal, temporal, occipital, insula). Since the left and right differences in lobar and insular volumes/thicknesses were not different among our groups, volume and cortical thickness were calculated for corresponding bilateral lobes. RESULTS: There was no significant difference in age between the whole migraine and the control groups. Migraineurs with WMLs (L+ patients) were significantly older than lesion-free (L-) patients (P = 0.0003) and controls (P = 0.018). Disease duration (P = 0.003), the total number of migraine attacks (P = 0.022) and the rate of aura (P = 0.0003) were significantly higher in L+ patients than in L- patients. Cortical thickness and volume measurements of lobes were not statistically different between the three groups (L+, L-, control). Age showed a significant negative association with both thickness and volume in each examined lobe (P < 0.001). Intracranial volume (ICV) showed a significant positive association with all regional volumes (P < 0.001). There were no significant group*age, group*ICV, or age*ICV interactions. None of the migraine characteristics were selected by stepwise linear regression as significant predictors of cortical thickness or volume. Only age (for both thickness and volume) and ICV (for volume) were identified as significant predictors (P < 0.001). When the L + group was divided into two subgroups by median split of total and lobar lesion number and volume, the cortical measures did not show any significant difference between the groups with low vs. high lesion number/volume by stepwise linear regression. CONCLUSIONS: In a female migraine group, we found that the WMLs and clinical migraine characteristics have no effect on cortical thickness and volume of bilateral lobes. Lobar cortical thicknesses were equivalent within the range of ±0.1 mm. Only age and ICV proved to be significant predictors; the former for both cortical thickness and volume, while the latter for cortical volume.


Assuntos
Córtex Cerebral/patologia , Transtornos de Enxaqueca/patologia , Substância Branca/patologia , Adolescente , Adulto , Idoso , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Transtornos de Enxaqueca/diagnóstico por imagem , Tamanho do Órgão , Substância Branca/diagnóstico por imagem , Adulto Jovem
5.
Ideggyogy Sz ; 69(5-6): 177-82, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-27468607

RESUMO

The objective of this study was to examine the relationship between verbal memory and total cholesterol (TC) levels related to body mass index (BMI) in healthy young women. Verbal memory was assessed using the Rey Auditory-Verbal Learning Test (RAVLT) while total serum cholesterol was measured by enzymatic colorimetric test. In order to analyze the potential significance of BMI subjects were divided into three groups according to their calculated BMI percentile values. No significant correlation was found when assessing the group as a whole. However a remarkable pattern of correlation emerged when assessing the BMI groups separately: a close-to-significant positive correlation was found for total learning score and TC in the low BMI group, no correlation emerged in the medium BMI group while a strong inverse correlation was found in the high BMI group. These findings indicate that the relationship between verbal memory and serum TC level is also influenced by BMI.


Assuntos
Índice de Massa Corporal , Colesterol/sangue , Memória , Aprendizagem Verbal , Adulto , Feminino , Humanos
6.
Mov Disord ; 30(10): 1422-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26230515

RESUMO

BACKGROUND: The pathophysiology of cervical dystonia is poorly understood. Increased brain iron deposition has been described in different movement disorders. Our aim was to investigate brain iron content in patients with cervical dystonia, using R2* relaxation rate, a validated MRI marker of brain iron level. METHODS: Twelve female patients with primary focal cervical dystonia (mean age: 45.4 ± 8.0 years) and 12 age-matched healthy female subjects (mean age: 45.0 ± 8.0 years) underwent 3T MRI to obtain regional R2* relaxation rates of the thalamus, caudate nucleus, putamen, and globus pallidus (GP). Regions of interest were delineated automatically on T1-weighted MRIs. RESULTS: R2* values in the putamen were positively correlated with age. Patients with cervical dystonia showed elevated R2* values in the GP. CONCLUSIONS: This pilot study provides the first quantitative support for increased brain iron deposition in cervical dystonia. Further studies are needed to explore the implications of this finding.


Assuntos
Globo Pálido/metabolismo , Ferro/metabolismo , Imageamento por Ressonância Magnética/métodos , Torcicolo/metabolismo , Adulto , Fatores Etários , Núcleo Caudado/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Putamen/metabolismo , Tálamo/metabolismo
7.
J Magn Reson Imaging ; 41(3): 676-83, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24677284

RESUMO

PURPOSE: To compare the white matter lesions seen in multiple sclerosis and migraine using monoexponential and high b-value biexponential diffusion measurements. MATERIALS AND METHODS: Diffusion-weighted images were acquired on a 3.0-Tesla magnetic resonance imaging system. Diffusion parameters were estimated using monoexponential (0-1000 s/mm(2) ) and biexponential (0-5000 s/mm(2) ) approaches from 15 multiple sclerosis patients, 15 patients with migraine and 15 healthy control subjects. The study was performed in accordance with the approval of the Regional Research Ethics Committee. The apparent diffusion coefficient (ADC) values were measured in the lesions and the normal-appearing white matter of patients and in the white matter of controls. RESULTS: High lesional ADCmono values were detected in both patient groups without significant differences between the groups (10.72 and 9.86 × 10(-4) mm(2) /s for MS and migraine respectively, P = 0.2134). The biexponential measurements showed significantly higher ADCfast , ADCslow , and Pslow values in the migraine lesions than in the multiple sclerosis lesions (16.47 versus 14.29, 1.41 versus 0.76, and 20.34 versus 12.01 all values in 10(-4) mm(2) /s; P = 0.0344, P = 0.0019, P = 0.0021, respectively). CONCLUSION: Biexponential diffusion analysis may help to differentiate multiple sclerosis-related white matter lesions from migraine-related ones.


Assuntos
Imagem de Difusão por Ressonância Magnética , Transtornos de Enxaqueca/patologia , Esclerose Múltipla/patologia , Substância Branca/patologia , Adulto , Feminino , Humanos , Imageamento Tridimensional , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes
8.
Headache ; 55(1): 55-70, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25319529

RESUMO

OBJECTIVE/BACKGROUND: The aim of this longitudinal study was to investigate changes of migraine-related brain white matter hyperintensities 3 years after an initial study. Baseline quantitative magnetic resonance imaging (MRI) studies of migraine patients with hemispheric white matter hyperintensities performed in 2009 demonstrated signs of tissue damage within the hyperintensities. The hyperintensities appeared most frequently in the deep white matter of the frontal lobe with a similar average hyperintensity size in all hemispheric lobes. Since in this patient group the repeated migraine attacks were the only known risk factors for the development of white matter hyperintensities, the remeasurements of migraineurs after a 3-year long follow-up may show changes in the status of these structural abnormalities as the effects of the repeated headaches. METHODS: The same patient group was reinvestigated in 2012 using the same MRI scanner and acquisition protocol. MR measurements were performed on a 3.0-Tesla clinical MRI scanner. Beyond the routine T1-, T2-weighted, and fluid-attenuated inversion recovery imaging, diffusion and perfusion-weighted imaging, proton magnetic resonance spectroscopy, and T1 and T2 relaxation time measurements were also performed. Findings of the baseline and follow-up studies were compared with each other. RESULTS: The follow-up proton magnetic resonance spectroscopy studies of white matter hyperintensities showed significantly decreased N-acetyl-aspartate (median values 8.133 vs 7.153 mmol/L, P=.009) and creatine/phosphocreatine (median values 4.970 vs 4.641 mmol/L, P=.015) concentrations compared to the baseline, indicating a more severe axonal loss and glial hypocellularity with decreased intracellular energy production. The diffusion values, the T1 and T2 relaxation times, and the cerebral blood flow and volume measurements presented only mild changes between the studies. The number (median values 21 vs 25, P<.001) and volume (median values 0.896 vs 1.140 mL, P<.001) of hyperintensities were significantly higher in the follow-up study. No changes were found in the hemispheric and lobar distribution of hyperintensities. An increase in the hyperintensity size of preexisting lesions was much more common than a decrease (median values 14 vs 5, P=.004). A higher number of newly developed hyperintensities were detected than disappeared ones (130 vs 22), and most of them were small (<.034 mL). Small white matter hyperintensities in patients with a low migraine attack frequency had a higher chance to disappear than large white matter hyperintensities or white matter hyperintensities in patients with a high attack frequency (coefficient: -0.517, P=.034). CONCLUSIONS: This longitudinal MRI study found clinically silent brain white matter hyperintensities to be predominantly progressive in nature. The absence of a control group precludes definitive conclusions about the nature of these changes or if their degree is beyond normal aging.


Assuntos
Leucoencefalopatias/etiologia , Leucoencefalopatias/patologia , Imageamento por Ressonância Magnética , Transtornos de Enxaqueca/complicações , Adulto , Idoso , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Creatina/metabolismo , Imagem de Difusão por Ressonância Magnética , Feminino , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Lateralidade Funcional , Humanos , Inositol/metabolismo , Estudos Longitudinais , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prótons , Adulto Jovem
9.
Nutr Neurosci ; 18(1): 37-40, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24524629

RESUMO

OBJECTIVES: Vitamin D is important in normal brain development. In animals low vitamin D level is associated with brain morphological alterations including enlargement of the brain. Whether a similar association exists in humans is unknown. Here we investigated the relationship between vitamin D and total intracranial volume as well as total volume of the cortical grey and cerebral white matter and that of the ventricles in young healthy women. METHODS: To assess volumes we applied semi-automatic user-independent MR volumetry. For the vitamin D measurements automated electrochemiluminescence immunoassay was used. RESULTS: We found a significant negative correlation between vitamin D and total intracranial volume as well as total cortical grey and cerebral white matter volumes. DISCUSSION: This association may reflect a trait-like relationship between vitamin D and brain size possibly determined in early development.


Assuntos
Encéfalo/patologia , Deficiência de Vitamina D/patologia , Vitamina D/análogos & derivados , Adolescente , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Vitamina D/sangue , Adulto Jovem
10.
Int J Food Sci Nutr ; 66(7): 826-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26436708

RESUMO

The objective of this study was to investigate the relation between habitual milk and dairy consumption and brain morphology as assessed by magnetic resonance imaging (MRI) investigations in 119 young healthy university students. MRI measurements were performed on a Siemens Magnetom Trio Tim (3T) system while FreeSurfer software suite was used for volumetric segmentation. Dietary habits related to milk and dairy consumption were assessed by a structured questionnaire. Total cerebral cortex, total cerebral white matter, and total cerebral parenchyma were significantly related with cottage cheese and total protein intake from milk and dairy also when controlled for age and gender in the multivariate model. Our results indicate that dietary habits related with milk and dairy are proportionally associated with volumes of both cerebral cortex and cerebral white matter.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Laticínios , Dieta , Comportamento Alimentar , Proteínas do Leite/farmacologia , Substância Branca/efeitos dos fármacos , Adolescente , Adulto , Animais , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/crescimento & desenvolvimento , Queijo , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Leite , Tamanho do Órgão , Valores de Referência , Inquéritos e Questionários , Substância Branca/anatomia & histologia , Substância Branca/crescimento & desenvolvimento , Adulto Jovem
11.
Ideggyogy Sz ; 68(9-10): 347-55, 2015 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-26665497

RESUMO

BACKGROUND AND PURPOSE: The differentiation of epidermoid cysts from other intracranial lesions with CT and conventional MR imaging is challenging. The risk of residual and recurrent disease is high and multimodal imaging should therefore promote a precise differential diagnosis. Since epidermoid cysts are histologically identical to middle ear cholesteatomas, MRI methods that are useful in the diagnosis of cholesteatoma; specifically EPI DWI and a non-EPI diffusion subtype (HASTE DWI) may possibly be applicable to epidermoid cysts. Besides testing the diagnostic utility of these methods on epidermoid cysts, our goal was to quantify the T1 and T2 relaxation times, the ADC values and the magnetization transfer ratios in order to acquire objective, characteristic information about their structure and contents. Finally, our goal was to provide the physician with a reliable, multimodal diagnostic tool that supports accurate surgical planning. METHODS: Two patients with epidermoid cysts were examined. Besides the conventional MR scans EPI DWI, HASTE DWI, quantitative T1, T2 and magnetization transfer measurements were performed mappingwith a 3T MR scanner. After image registration, T1, T2 relaxation times and the magnetization transfer ratio inside a ROI were determined according to the lesion location on HASTE DWI. Mean ADC values inside the epidermoid cysts were also calculated by both mono-exponential and bi-exponential diffusion models. RESULTS: Our results revealed relatively high T1 and T2 relaxation times and ADC values, and low magnetization transfer ratios in both subjects. CONCLUSION: HASTE-DW MRI provides accurate morphologic information on epidermoid cysts, while T1, T2, ADC and magnetization transfer ratio maps are quantitative techniques. Thus the combination of these methods results in a confident preoperative diagnosis and aids to determine the indication of retreatment in the event of recurrence.


Assuntos
Encefalopatias/diagnóstico , Cisto Epidérmico/diagnóstico , Imageamento por Ressonância Magnética , Imagem Multimodal/métodos , Adulto , Encefalopatias/patologia , Imagem de Difusão por Ressonância Magnética , Cisto Epidérmico/patologia , Humanos , Masculino , Pessoa de Meia-Idade
12.
Nutr Neurosci ; 17(6): 284-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24593042

RESUMO

OBJECTIVE: Vitamin D plays an important role in brain development and functioning. Low levels of vitamin D have been described in several psychiatric and neurologic conditions including autism spectrum disorder. Alexithymia that shows high comorbidity with autism is also present in the general population as well as hypovitaminosis D. METHODS: Here we assessed the relation between alexithymia as measured by the Toronto Alexithymia Scale-20 and vitamin D level in healthy young adults. Results We found an inverse correlation between the levels of alexithymia and vitamin D. DISCUSSION: These data suggest the association between disturbed emotional processing and low levels of vitamin D to be present in young healthy subjects.


Assuntos
Sintomas Afetivos/sangue , Transtorno Autístico/epidemiologia , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia , Vitamina D/sangue , Adulto , Sintomas Afetivos/complicações , Transtorno Autístico/sangue , Comorbidade , Feminino , Voluntários Saudáveis , Humanos , Masculino , Inquéritos e Questionários , Deficiência de Vitamina D/complicações , Adulto Jovem
13.
Headache ; 53(5): 752-63, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23278630

RESUMO

OBJECTIVE: The aim of this study was to examine chronic brain white matter hyperintensities in migraine and to gain data on the characteristics of the lesions. BACKGROUND: Migraine associates with a higher incidence of magnetic resonance imaging (MRI)-visible white matter signal abnormalities. Several attack-related pathomechanisms have been proposed in the lesion development, including the effect of repeated intracerebral hemodynamic changes. METHODS: Supratentorial white matter hyperintensities of 17 migraine patients were investigated interictally with quantitative MRI, including quantitative single voxel spectroscopy, diffusion, and perfusion MRI at 3.0-Tesla. The findings were compared with data measured in the contralateral, normal-appearing white matter of migraineurs and in the white matter of 17 healthy subjects. RESULTS: Significantly higher apparent diffusion coefficient values, prolonged T2 relaxation times, and decreased N-acetyl-aspartate and creatine/phosphocreatine concentrations were found in the white matter hyperintensities. The cerebral blood flow and blood volume values were mildly decreased inside the hyperintensities. Differences were not present between the migraine patients' normal-appearing white matter and the white matter of healthy subjects. CONCLUSIONS: The MRI measurements denote tissue damage with axonal loss, low glial cell density, and an enlarged extracellular space with an increased extracellular water fraction. These radiological features might be the consequences of microvascular ischemic changes during migraine attacks.


Assuntos
Encéfalo/fisiopatologia , Transtornos de Enxaqueca/fisiopatologia , Fibras Nervosas Mielinizadas/patologia , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas Mielinizadas/metabolismo , Adulto Jovem
14.
Sci Rep ; 13(1): 5598, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019923

RESUMO

Middle cerebral artery occlusion (MCAO) models show substantial variability in outcome, introducing uncertainties in the evaluation of treatment effects. Early outcome predictors would be essential for prognostic purposes and variability control. We aimed to compare apparent diffusion coefficient (ADC) MRI data obtained during MCAO and shortly after reperfusion for their potentials in acute-phase outcome prediction. Fifty-nine male rats underwent a 45-min MCAO. Outcome was defined in three ways: 21-day survival; 24 h midline-shift and neurological scores. Animals were divided into two groups: rats surviving 21 days after MCAO (survival group, n = 46) and rats dying prematurely (non-survival/NS group, n = 13). At reperfusion, NS group showed considerably larger lesion volume and lower mean ADC of the initial lesion site (p < 0.0001), while during occlusion there were no significant group differences. At reperfusion, each survival animal showed decreased lesion volume and increased mean ADC of the initial lesion site compared to those during occlusion (p < 10-6), while NS group showed a mixed pattern. At reperfusion, lesion volume and mean ADC of the initial lesion site were significantly associated with 24 h midline-shift and neurological scores. Diffusion MRI performed soon after reperfusion has a great impact in early-phase outcome prediction, and it works better than the measurement during occlusion.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Ratos , Masculino , Animais , Imageamento por Ressonância Magnética , Imagem de Difusão por Ressonância Magnética , Infarto da Artéria Cerebral Média/patologia , Reperfusão , Difusão , Modelos Animais de Doenças , Isquemia Encefálica/patologia
15.
Brain Imaging Behav ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38049599

RESUMO

Nowadays, the limitless availability to the World Wide Web can lead to general Internet misuse and dependence. Currently, smartphone and social media use belong to the most prevalent Internet-related behavioral addiction forms. However, the neurobiological background of these Internet-related behavioral addictions is not sufficiently explored. In this study, these addiction forms were assessed with self-reported questionnaires. Resting-state functional magnetic resonance imaging was acquired for all participants (n = 59, 29 males) to examine functional brain networks. The resting-state networks that were discovered using independent component analysis were analyzed to estimate within network differences. Significant negative associations with social media addiction and smartphone addiction were found in the language network, the lateral visual networks, the auditory network, the sensorimotor network, the executive network and the frontoparietal network. These results suggest that problematic smartphone and social media use are associated with sensory processing and higher cognitive functioning.

16.
Sci Rep ; 13(1): 354, 2023 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-36611073

RESUMO

Growing literature indicates that problematic Internet use (PIU) and excessive smartphone use (ESU) are associated with breakdown of functional brain networks. The effects of PIU&ESU on emotional face expression (EFE) recognition are not well understood, however behavioural investigations and fMRI studies of different addiction forms indicated the impairment of this function. The Facial Emotion Recognition Paradigm was used to probe cortico-limbic responses during EFE recognition. Combined fMRI and psychophysiological analysis were implemented to measure EFE-related functional brain changes in PIU&ESU. Self-reported questionnaires were used to assess PIU&ESU. Positive associations were found between the extent of PIU&ESU and functional connections related to emotional cognitive control and social brain networks. Our findings highlight the involvement of social functioning, especially EFE recognition in PIU&ESU. Therefore, we emphasize that besides the brain's executive and reward systems, the social brain network might be the next candidate to be involved in the pathogenesis of PIU&ESU.


Assuntos
Comportamento Aditivo , Reconhecimento Facial , Humanos , Smartphone , Expressão Facial , Imageamento por Ressonância Magnética , Uso da Internet , Comportamento Aditivo/psicologia , Internet
17.
PLoS One ; 17(6): e0269979, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35749379

RESUMO

Internet use disorder (IUD) is generally conceptualized as a fast-growing behavioral addiction. Several structural and functional brain alterations have been revealed in this condition, but previous behavioral studies indicated that language systems may also be impaired. We used a silent word generation task to induce brain activation in Broca's area and other parts of the language system. Blood-oxygen-level-dependent activation analysis and psychophysiological interaction analysis were applied to assess functional brain changes. IUD was measured by the Problematic Internet Use Questionnaire and two additional questions concerning usage time and subjective rating of addiction. According to our key findings, areas strongly related to the default mode network were altered in IUD during the task. Moreover, Broca's area showed altered functional connectivity with other language network and occipital areas in IUD. These findings may address the neural background of decreased verbal fluency performance previously reported in the literature, and we emphasize that beside the brain's reward and inhibitory control systems, the language system is the next candidate to be involved in the pathogenesis of IUD.


Assuntos
Idioma , Imageamento por Ressonância Magnética , Mapeamento Encefálico , Área de Broca , Uso da Internet
18.
Sci Rep ; 12(1): 808, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039541

RESUMO

The widely used rubber hand illusion (RHI) paradigm provides insight into how the brain manages conflicting multisensory information regarding bodily self-consciousness. Previous functional neuroimaging studies have revealed that the feeling of body ownership is linked to activity in the premotor cortex, the intraparietal areas, the occipitotemporal cortex, and the insula. The current study investigated whether the individual differences in the sensation of body ownership over a rubber hand, as measured by subjective report and the proprioceptive drift, are associated with structural brain differences in terms of cortical thickness in 67 healthy young adults. We found that individual differences measured by the subjective report of body ownership are associated with the cortical thickness in the somatosensory regions, the temporo-parietal junction, the intraparietal areas, and the occipitotemporal cortex, while the proprioceptive drift is linked to the premotor area and the anterior cingulate cortex. These results are in line with functional neuroimaging studies indicating that these areas are indeed involved in processes such as cognitive-affective perspective taking, visual processing of the body, and the experience of body ownership and bodily awareness. Consequently, these individual differences in the sensation of body ownership are pronounced in both functional and structural differences.


Assuntos
Imagem Corporal/psicologia , Ilusões/fisiologia , Individualidade , Córtex Motor/anatomia & histologia , Córtex Motor/fisiologia , Propriedade , Sensação/fisiologia , Adulto , Feminino , Humanos , Masculino , Córtex Somatossensorial/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
19.
Neurobiol Stress ; 15: 100399, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34646916

RESUMO

IMPORTANCE AND OBJECTIVES: Childhood adversity is a strong risk factor for the development of various psychopathologies including major depressive disorder (MDD). However, not all depressed patients experience early life trauma. Functional magnetic resonance imaging (fMRI) studies using facial emotion processing tasks have documented altered blood-oxygen-level-dependent (BOLD) responses in specific cortico-limbic networks both in MDD patients and in individuals with a history of childhood maltreatment (CM). Therefore, a history of maltreatment may represent a key modulating factor responsible for the altered processing of socio-affective stimuli. To test this hypothesis, we recruited MDD patients with and without of maltreatment history to study the long-term consequences of childhood trauma and examined the impact of CM on brain activity using a facial emotion recognition fMRI task. METHODS: MDD patients with childhood maltreatment (MDD + CM, n = 21), MDD patients without maltreatment (MDD, n = 19), and healthy controls (n = 21) matched for age, sex and intelligence quotient underwent fMRI while performing a block design facial emotion matching task with images portraying negative emotions (fear, anger and sadness). The history of maltreatment was assessed with the 28-item Childhood Trauma Questionnaire. RESULTS: Both MDD and MDD + CM patients displayed impaired accuracy to recognize sad faces. Analysis of brain activity revealed that MDD + CM patients had significantly reduced negative BOLD signals in their right accumbens, subcallosal cortex, and anterior paracingulate gyrus compared to controls. Furthermore, MDD + CM patients had a significantly increased negative BOLD response in their right precentral and postcentral gyri compared to controls. We found little difference between MDD and MDD + CM patients, except that MDD + CM patients had reduced negative BOLD response in their anterior paracingulate gyrus relative to the MDD group. CONCLUSIONS: Our present data provide evidence that depressed patients with a history of maltreatment are impaired in facial emotion recognition and that they display altered functioning of key reward-related fronto-striatal circuits during a facial emotion matching task.

20.
Sci Rep ; 11(1): 1179, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441889

RESUMO

The absence of nigral hyperintensity is a promising MR marker for Parkinson's disease (PD), but its small size imposes limitations on its routine use. Our aim was to compare Multi Echo Data Image Combination (MEDIC), segmented echo-planar imaging (EPISEG) and fluid-attenuated inversion recovery (FLAIR) sequences, as well as both magnitude (MAG) and susceptibility-weighted imaging (SWI) reconstructions of single-echo gradient echo for nigral hyperintensity imaging. Twenty-five healthy and twenty PD subjects were included. Sensitivity to motion artefacts, confidence of the radiologist in interpretation, rate of nondiagnostic scans and diagnostic accuracy were assessed. EPISEG was less motion-sensitive than MEDIC, MAG, and SWI, while FLAIR was less motion-sensitive than MAG and SWI. The reviewers were more confident when using EPISEG compared to any other techniques and MEDIC was superior to FLAIR. The proportions of nondiagnostic scans were lower for EPISEG than for other sequences. The best diagnostic performance was achieved for EPISEG (sensitivity = 65%, specificity = 96%). Using EPISEG, the absence of nigral hyperintensity in PD was associated with higher Hoehn-Yahr stage and MDS-UPDRS II + III. Nigral hyperintensity may be intact at the very early stages of PD. The promising properties of EPISEG may help the transfer of nigral hyperintensity imaging into daily clinical practice.


Assuntos
Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Adulto , Idoso , Biomarcadores/metabolismo , Imagem Ecoplanar/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Substância Negra/patologia
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