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1.
Cerebellum ; 15(4): 483-90, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26298474

RESUMO

Machado-Joseph disease (MJD) is the most common spinocerebellar ataxia worldwide with a broad range of clinical manifestations, but psychotic symptoms were not previously characterized. We investigated the psychiatric manifestations of a large cohort of Brazilian patients with MJD in an attempt to characterize the presence of psychotic symptoms. We evaluated 112 patients with clinical and molecular diagnosis of MJD from February 2008 to November 2013. Patients with psychotic symptoms were referred to psychiatric evaluation and brain perfusion single-photon emission computed tomography (SPECT) analysis. A specific scale-Positive and Negative Syndrome Scale (PANSS)-was used to characterize psychotic symptoms in MJD patients. We also performed an autopsy from one of the patients with MJD and psychotic symptoms. Five patients presented psychotic symptoms. Patients with psychotic symptoms were older and had a late onset of the disease (p < 0.05). SPECT results showed that MJD patients had significant regional cerebral blood flow (rCBF) decrease in the cerebellum bilaterally and vermis compared with healthy subjects. No significant rCBF differences were found in patients without psychotic symptoms compared to patients with psychotic symptoms. The pathological description of a patient with MJD and psychotic symptoms revealed severe loss of neuron bodies in the dentate nucleus and substantia nigra. MJD patients with a late onset of the disease and older ones are at risk to develop psychotic symptoms during the disease progression. These clinical findings may be markers for an underlying cortical-cerebellar disconnection or degeneration of specific cortical and subcortical regions that may characterize the cerebellar cognitive affective syndrome.


Assuntos
Encéfalo/metabolismo , Doença de Machado-Joseph/epidemiologia , Doença de Machado-Joseph/metabolismo , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/metabolismo , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Brasil/epidemiologia , Circulação Cerebrovascular/fisiologia , Estudos de Coortes , Feminino , Humanos , Doença de Machado-Joseph/complicações , Doença de Machado-Joseph/patologia , Masculino , Pessoa de Meia-Idade , Neurônios/patologia , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/complicações , Transtornos Psicóticos/patologia , Tomografia Computadorizada de Emissão de Fóton Único
2.
Eur Radiol ; 26(9): 3234-42, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26747258

RESUMO

OBJECTIVE: Investigate the effect of acupuncture on brain perfusion using ethyl cysteinate dimer single-photon emission computed tomography ((99m)Tc-ECD SPECT) in patients with tinnitus. METHODS: This randomized, single-blind, sham-control study examined patients (18-60 years old) with normal hearing and chronic, idiopathic, continuous tinnitus. Fifty-seven subjects were randomly assigned to true (n = 30) or sham (n = 27) acupuncture (ACP); (99m)Tc-ECD SPECT examinations were performed before and after 12 twice-weekly ACP sessions. Secondary outcomes included changes in the Tinnitus Handicap Inventory (THI), Visual Analog Scale (VAS), Hamilton Anxiety Scale (HAS) and Beck Depression Inventory (BDI). Imaging data were analysed using Statistical Parametric Mapping (SPM8) software. Regression models were used to examine secondary outcomes via two paradigms: intention-to-treat (ITT; where multiple imputations were conducted because of study attrition) and complete cases. RESULTS: No between-group brain perfusion differences were observed. However, a significant improvement in THI scores was observed at the end of true ACP treatment for all domains (all p values < 0.01) except the catastrophic scale. CONCLUSIONS: ACP might reduce the effects of tinnitus on daily life; however, additional studies should be conducted to verify the effects of ACP on the neural architecture and brain function of tinnitus patients. KEY POINTS: • Efficacy of acupuncture on brain perfusion and symptoms of tinnitus patients. • Acupuncture improved the Tinnitus Handicap Inventory scores in tinnitus patients. • No significant changes in brain perfusion were observed after 12 twice-weekly sessions. • Perfusion changes would reflect changes in neuronal function.


Assuntos
Terapia por Acupuntura/métodos , Encéfalo/diagnóstico por imagem , Cistina/análogos & derivados , Tecnécio , Zumbido/terapia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Adolescente , Adulto , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do Tratamento , Adulto Jovem
3.
Eur Heart J ; 33(14): 1769-76, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22296945

RESUMO

AIMS: It is unclear whether the cognitive dysfunction associated with heart failure (HF) is due to HF or comorbid conditions such as ischaemic heart disease (IHD). This study aimed to determine whether, compared with controls with and without IHD, adults with systolic HF show evidence of cognitive impairment and cerebral grey matter (GM) loss. METHODS AND RESULTS: Cross-sectional study of 35 participants with HF, 56 with IHD, and 64 controls without either HF or IHD. Subjects were older than 45 years and free of overt cognitive impairment. We acquired magnetic resonance images and used SPM8 to determine regional differences in cerebral GM volume. Participants with HF had lower scores than controls without IHD on immediate memory, long delay recall and digit coding, whereas those with IHD had lower long delay recall scores than controls without IHD. Compared with controls without IHD, participants with HF showed evidence of GM loss in the left cingulate, the right inferior frontal gyrus, the left middle and superior frontal gyri, the right middle temporal lobe, the right and left anterior cingulate, the right middle frontal gyrus, the inferior and pre-central frontal gyri, the right caudate, and occipital-parietal regions involving the left precuneus. The loss of GM followed a similar, less extensive, pattern when we compared participants with HF and IHD. CONCLUSION: Adults with HF have worse immediate and long-term memory and psychomotor speed than controls without IHD. Heart failure is associated with changes in brain regions that are important for demanding cognitive and emotional processing.


Assuntos
Encefalopatias/etiologia , Transtornos Cognitivos/etiologia , Insuficiência Cardíaca Sistólica/complicações , Isquemia Miocárdica/complicações , Idoso , Encefalopatias/patologia , Transtornos Cognitivos/patologia , Estudos Transversais , Feminino , Insuficiência Cardíaca Sistólica/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/patologia
4.
Cerebellum ; 11(4): 1037-44, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22307858

RESUMO

Cognitive and olfactory impairments have previously been demonstrated in patients with spinocerebellar ataxia type 3 (SCA3), also known as Machado-Joseph disease (MJD)-SCA3/MJD. We investigated changes in regional cerebral blood flow (rCBF) using single-photon emission computed tomography (SPECT) imaging in a cohort of Brazilian patients with SCA3/MJD. The aim of the present study was to evaluate the correlation among rCBF, cognitive deficits, and olfactory dysfunction in SCA3/MJD. Twenty-nine genetically confirmed SCA3/MJD patients and 25 control subjects were enrolled in the study. The severity of cerebellar symptoms was measured using the International Cooperative Ataxia Rating Scale and the Scale for the Assessment and Rating of Ataxia. Psychiatric symptoms were evaluated by the Hamilton Anxiety Scale and Beck Depression Inventory. The neuropsychological assessment consisted of Spatial Span, Symbol Search, Picture Completion, the Stroop Color Word Test, Trail Making Test (TMT), and Phonemic Verbal Fluency. Subjects were also submitted to odor identification evaluation using the 16-item Sniffin' Sticks. SPECT was performed using ethyl cysteine dimer labeled with technetium-99m. SCA3/MJD patients showed reduced brain perfusion in the cerebellum, temporal, limbic, and occipital lobes compared to control subjects (pFDR <0.001). A significant positive correlation was found between the Picture Completion test and perfusion of the left parahippocampal gyrus and basal ganglia in the patient group as well as a negative correlation between the TMT part A and bilateral thalamus perfusion. The visuospatial system is affected in patients with SCA3/MJD and may be responsible for the cognitive deficits seen in this disease.


Assuntos
Transtornos Cognitivos/fisiopatologia , Doença de Machado-Joseph/fisiopatologia , Acuidade Visual , Adulto , Ansiedade/fisiopatologia , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Transtornos Cognitivos/etiologia , Feminino , Humanos , Doença de Machado-Joseph/complicações , Doença de Machado-Joseph/diagnóstico , Doença de Machado-Joseph/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Perfusão/efeitos adversos , Tomografia Computadorizada de Emissão de Fóton Único
5.
Neuroimage ; 55(4): 1480-9, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21281718

RESUMO

BACKGROUND: Observational studies investigating the association between smoking, cognitive decline and dementia have produced conflicting results. We completed this trial to determine if smoking cessation decreases the progression of cognitive decline in later life. METHODS: We recruited older smokers (n=229) and never smokers (n=98) and invited smokers to join a smoking cessation trial. The primary outcome of interest was change in Alzheimer's Disease Assessment Scale cognitive subscale (ADAS-cog) scores over 24 months. Secondary measures included the Logical Memory test and changes in gray matter density. Successful smoking cessation was defined as a minimum of 547 smoking free days during follow up. RESULTS: The ADAS-cog scores of unsuccessful quitters (UQ) increased (i.e., became worse) 1.1±0.3 and 1.2±0.4 points more than the scores of never smokers (NS) (p=0.001) and successful quitters (SQ) (p=0.006) respectively over the 24 months of follow up. Similarly, the scores of UQ declined (i.e., became worse) relative to NS on measures of immediate (p=0.004) and delayed recall (p=0.029). All analyses were adjusted for age, years of education, baseline cognitive performance, alcohol use, depression scores, and the presence of chronic respiratory disease. Thirty-six NS, 18 SQ and 48 UQ completed the imaging substudy. Compared with NS, UQ showed a disproportional loss of gray matter density in the right thalamus, right and left inferior semi-lunar lobule, as well as left superior and inferior parietal lobule over 24 months. SQ showed loss of gray matter compared with NS in the right middle and inferior occipital gyri, right and left culmen, and the left superior frontal gyrus. We did not find any brain regions in which UQ had lost more gray matter than SQ over 2 years. CONCLUSION: These results are consistent with the hypothesis that smoking causes cognitive decline and loss of gray matter tissue in the brain over time.


Assuntos
Envelhecimento/patologia , Encéfalo/patologia , Transtornos Cognitivos/patologia , Transtornos Cognitivos/fisiopatologia , Abandono do Hábito de Fumar , Fumar/patologia , Fumar/fisiopatologia , Adulto , Idoso , Encéfalo/fisiopatologia , Cognição , Transtornos Cognitivos/etiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fumar/efeitos adversos , Adulto Jovem
6.
Psychiatry Res ; 192(1): 37-44, 2011 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-21377844

RESUMO

Male bonnet monkeys (Macaca radiata) were subjected to the variable foraging demand (VFD) early stress paradigm as infants, MRI scans were completed an average of 4 years later, and behavioral assessments of anxiety and ex-vivo corpus callosum (CC) measurements were made when animals were fully matured. VFD rearing was associated with smaller CC size, CC measurements were found to correlate with fearful behavior in adulthood, and ex-vivo CC assessments showed high consistency with earlier MRI measures. Region of interest (ROI) hippocampus and whole brain voxel-based morphometry assessments were also completed and VFD rearing was associated with reduced hippocampus and inferior and middle temporal gyri volumes. The animals were also characterized according to serotonin transporter genotype (5-HTTLPR), and the effect of genotype on imaging parameters was explored. The current findings highlight the importance of future research to better understand the effects of stress on brain development in multiple regions, including the corpus callosum, hippocampus, and other regions involved in emotion processing. Nonhuman primates provide a powerful model to unravel the mechanisms by which early stress and genetic makeup interact to produce long-term changes in brain development, stress reactivity, and risk for psychiatric disorders.


Assuntos
Ansiedade/patologia , Ansiedade/fisiopatologia , Corpo Caloso , Hipocampo , Estresse Psicológico/patologia , Estresse Psicológico/fisiopatologia , Análise de Variância , Animais , Comportamento Animal , Mapeamento Encefálico , Corpo Caloso/crescimento & desenvolvimento , Corpo Caloso/patologia , Corpo Caloso/fisiopatologia , Estudos Transversais , Medo , Frequência do Gene , Genótipo , Hipocampo/crescimento & desenvolvimento , Hipocampo/patologia , Hipocampo/fisiopatologia , Processamento de Imagem Assistida por Computador , Modelos Lineares , Macaca radiata , Imageamento por Ressonância Magnética , Masculino , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética
7.
Cereb Cortex ; 19(2): 276-83, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18502730

RESUMO

Social values are composed of social concepts (e.g., "generosity") and context-dependent moral sentiments (e.g., "pride"). The neural basis of this intricate cognitive architecture has not been investigated thus far. Here, we used functional magnetic resonance imaging while subjects imagined their own actions toward another person (self-agency) which either conformed or were counter to a social value and were associated with pride or guilt, respectively. Imagined actions of another person toward the subjects (other-agency) in accordance with or counter to a value were associated with gratitude or indignation/anger. As hypothesized, superior anterior temporal lobe (aTL) activity increased with conceptual detail in all conditions. During self-agency, activity in the anterior ventromedial prefrontal cortex correlated with pride and guilt, whereas activity in the subgenual cingulate solely correlated with guilt. In contrast, indignation/anger activated lateral orbitofrontal-insular cortices. Pride and gratitude additionally evoked mesolimbic and basal forebrain activations. Our results demonstrate that social values emerge from coactivation of stable abstract social conceptual representations in the superior aTL and context-dependent moral sentiments encoded in fronto-mesolimbic regions. This neural architecture may provide the basis of our ability to communicate about the meaning of social values across cultural contexts without limiting our flexibility to adapt their emotional interpretation.


Assuntos
Encéfalo/fisiologia , Imageamento por Ressonância Magnética , Valores Sociais , Adulto , Altruísmo , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Individualidade , Masculino , Princípios Morais , Vias Neurais/fisiologia , Prosencéfalo/fisiologia , Tempo de Reação/fisiologia , Recompensa , Lobo Temporal/fisiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-25688193

RESUMO

In this methods article, we present a new implementation of a recently reported FSL-integrated neurofeedback tool, the standalone version of "Functional Real-time Interactive Endogenous Neuromodulation and Decoding" (FRIEND). We will refer to this new implementation as the FRIEND Engine Framework. The framework comprises a client-server cross-platform solution for real time fMRI and fMRI/EEG neurofeedback studies, enabling flexible customization or integration of graphical interfaces, devices, and data processing. This implementation allows a fast setup of novel plug-ins and frontends, which can be shared with the user community at large. The FRIEND Engine Framework is freely distributed for non-commercial, research purposes.

10.
Neurobiol Aging ; 24(2): 221-31, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12498956

RESUMO

Several MRI studies have reported reductions in temporal lobe volumes in Alzheimer's disease (AD). Measures have been usually obtained with regions-of-interest (ROI) drawn manually on selected medial and lateral portions of the temporal lobes, with variable choices of anatomical borders across different studies. We used the fully automated voxel-based morphometry (VBM) approach to investigate gray matter abnormalities over the entire extension of the temporal lobe in 14 AD patients (MMSE 14-25) and 14 healthy controls. Foci of significantly reduced gray matter volume in AD patients were detected in both medial and lateral temporal regions, most significantly in the right and left posterior parahippocampal gyri and the left posterior inferior temporal gyrus/fusiform gyrus (P<0.05, corrected for multiple comparisons). At a more flexible statistical threshold (P<0.001, uncorrected for multiple comparisons), circumscribed foci of significant gray matter reduction were also detected in the right amygdala/enthorinal cortex, the anterior and posterior borders of the superior temporal gyrus bilaterally, and the anterior portion of the left middle temporal gyrus. These VBM results confirm previous findings of temporal lobe atrophic changes in AD, and suggest that these abnormalities may be confined to specific sites within that lobe, rather than showing a widespread distribution.


Assuntos
Doença de Alzheimer/patologia , Imageamento por Ressonância Magnética , Lobo Temporal/patologia , Idoso , Envelhecimento/patologia , Atrofia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Neuropsychopharmacology ; 29(2): 417-26, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14583744

RESUMO

Animal and human studies have suggested that cannabidiol (CBD) may possess anxiolytic properties, but how these effects are mediated centrally is unknown. The aim of the present study was to investigate this using functional neuroimaging. Regional cerebral blood flow (rCBF) was measured at rest using (99m)Tc-ECD SPECT in 10 healthy male volunteers, randomly divided into two groups of five subjects. Each subject was studied on two occasions, 1 week apart. In the first session, subjects were given an oral dose of CBD (400 mg) or placebo, in a double-blind procedure. SPECT images were acquired 90 min after drug ingestion. The Visual Analogue Mood Scale was applied to assess subjective states. In the second session, the same procedure was performed using the drug that had not been administered in the previous session. Within-subject between-condition rCBF comparisons were performed using statistical parametric mapping (SPM). CBD significantly decreased subjective anxiety and increased mental sedation, while placebo did not induce significant changes. Assessment of brain regions where anxiolytic effects of CBD were predicted a priori revealed two voxel clusters of significantly decreased ECD uptake in the CBD relative to the placebo condition (p<0.001, uncorrected for multiple comparisons). These included a medial temporal cluster encompassing the left amygdala-hippocampal complex, extending into the hypothalamus, and a second cluster in the left posterior cingulate gyrus. There was also a cluster of greater activity with CBD than placebo in the left parahippocampal gyrus (p<0.001). These results suggest that CBD has anxiolytic properties, and that these effects are mediated by an action on limbic and paralimbic brain areas.


Assuntos
Ansiolíticos/farmacologia , Canabidiol/farmacologia , Córtex Cerebral/efeitos dos fármacos , Cisteína/análogos & derivados , Fluxo Sanguíneo Regional/efeitos dos fármacos , Adulto , Ansiedade/tratamento farmacológico , Ansiedade/fisiopatologia , Mapeamento Encefálico , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Cisteína/farmacocinética , Método Duplo-Cego , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Testes Neuropsicológicos , Compostos de Organotecnécio/farmacocinética , Medição da Dor , Compostos Radiofarmacêuticos/farmacocinética , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único
12.
J Affect Disord ; 68(2-3): 295-305, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12063157

RESUMO

BACKGROUND: Delusions and/or hallucinations are not an uncommon feature in severe major depressive episodes. Functional imaging studies of depression have been widely reported in the literature, but few of these have attempted to investigate the neurophysiological correlates of psychotic symptoms. METHODS: We measured resting regional cerebral blood flow (rCBF) with the (99m)Tc-ECD SPECT technique in patients with major depressive disorder with (n=9) and without (n=12) psychotic features, as well as in a group of healthy volunteers (n=12). Between-group rCBF comparisons were performed using the voxel-based statistical parametric mapping method. RESULTS: Major depressed patients with psychotic features showed decreased rCBF in the left subgenual anterior cingulate cortex relative to both non-psychotic patients and healthy controls (P<0.001 one-tailed, uncorrected for multiple comparisons). Relative to the non-psychotic group, depressed patients with psychotic symptoms also had a focus of decreased rCBF in the right inferior frontal cortex, with the voxel of maximal significance in the insula (P<0.031, corrected for multiple comparisons). A similar pattern of significant between-group rCBF differences between psychotic and non-psychotic patients emerged after covarying the analysis for the confounding influence of overall illness severity. CONCLUSIONS: These results provide preliminary evidence that psychotic symptoms in major depression may be associated with abnormalities in ventral paralimbic regions previously implicated in mood regulation and depression.


Assuntos
Transtorno Depressivo Maior/diagnóstico por imagem , Giro do Cíngulo/irrigação sanguínea , Transtornos Psicóticos/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Afeto/fisiologia , Mapeamento Encefálico , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/psicologia , Dominância Cerebral/fisiologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/fisiopatologia , Transtornos Psicóticos/psicologia , Fluxo Sanguíneo Regional/fisiologia
13.
Soc Cogn Affect Neurosci ; 9(11): 1676-83, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24106333

RESUMO

Proneness to specific moral sentiments (e.g. pride, gratitude, guilt, indignation) has been linked with individual variations in functional MRI (fMRI) response within anterior brain regions whose lesion leads to inappropriate behaviour. However, the role of structural anatomical differences in rendering individuals prone to particular moral sentiments relative to others is unknown. Here, we investigated grey matter volumes (VBM8) and proneness to specific moral sentiments on a well-controlled experimental task in healthy individuals. Individuals with smaller cuneus, and precuneus volumes were more pride-prone, whereas those with larger right inferior temporal volumes experienced gratitude more readily. Although the primary analysis detected no associations with guilt- or indignation-proneness, subgenual cingulate fMRI responses to guilt were negatively correlated with grey matter volumes in the left superior temporal sulcus and anterior dorsolateral prefrontal cortices (right >left). This shows that individual variations in functional activations within critical areas for moral sentiments were not due to grey matter volume differences in the same areas. Grey matter volume differences between healthy individuals may nevertheless play an important role by affecting posterior cortical brain systems that are non-critical but supportive for the experience of specific moral sentiments. This may be of particular relevance when their experience depends on visuo-spatial elaboration.


Assuntos
Córtex Cerebral/fisiologia , Culpa , Individualidade , Princípios Morais , Estatística como Assunto , Adulto , Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Adulto Jovem
14.
J Alzheimers Dis ; 42(4): 1251-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25024333

RESUMO

Reduced awareness of cognitive deficits in mild cognitive impairment (MCI) is associated with poorer outcomes although little is known about the anatomical correlates of this. We examined the association of insight and grey matter volume using a voxel-based morphometry approach in 65 volunteers with MCI and 55 healthy age-matched controls. Participants with MCI had multiple areas of subtle grey matter volume loss compared with controls, although these did not survive correction for multiple comparisons. These were predominantly in the temporal and anterior portions of the brain. Individuals with MCI did not differ from each other on a number of demographic and cognitive variables according to level of insight. Reduced awareness of cognitive deficits was associated with few differences in grey matter volume apart from a subtle loss of grey matter in the medial frontal gyri. Given the modest nature of these findings, the routine assessment of insight in non-clinical populations of individuals with MCI is therefore not supported. Prospective data in larger samples, however, would be helpful to clarify this further and determine if impaired insight predicts brain atrophy and cognitive decline.


Assuntos
Conscientização , Encéfalo/patologia , Transtornos Cognitivos/patologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/psicologia , Substância Cinzenta/patologia , Idoso , Estudos Transversais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tamanho do Órgão
15.
PLoS One ; 9(2): e87839, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24516567

RESUMO

UNLABELLED: Tinnitus is characterized by the perception of sound in the absence of an external auditory stimulus. The network connectivity of auditory and non-auditory brain structures associated with emotion, memory and attention are functionally altered in debilitating tinnitus. Current studies suggest that tinnitus results from neuroplastic changes in the frontal and limbic temporal regions. The objective of this study was to use Single-Photon Emission Computed Tomography (SPECT) to evaluate changes in the cerebral blood flow in tinnitus patients with normal hearing compared with healthy controls. METHODS: Twenty tinnitus patients with normal hearing and 17 healthy controls, matched for sex, age and years of education, were subjected to Single Photon Emission Computed Tomography using the radiotracer ethylenedicysteine diethyl ester, labeled with Technetium 99 m (99 mTc-ECD SPECT). The severity of tinnitus was assessed using the "Tinnitus Handicap Inventory" (THI). The images were processed and analyzed using "Statistical Parametric Mapping" (SPM8). RESULTS: A significant increase in cerebral perfusion in the left parahippocampal gyrus (pFWE <0.05) was observed in patients with tinnitus compared with healthy controls. The average total THI score was 50.8+18.24, classified as moderate tinnitus. CONCLUSION: It was possible to identify significant changes in the limbic system of the brain perfusion in tinnitus patients with normal hearing, suggesting that central mechanisms, not specific to the auditory pathway, are involved in the pathophysiology of symptoms, even in the absence of clinically diagnosed peripheral changes.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Imageamento Tridimensional , Memória , Rede Nervosa/fisiopatologia , Zumbido/fisiopatologia , Adulto , Estudos de Casos e Controles , Circulação Cerebrovascular , Demografia , Feminino , Humanos , Masculino
16.
Eur J Heart Fail ; 15(8): 850-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23463084

RESUMO

AIMS: Heart failure (HF) has been associated with cognitive dysfunction, a high prevalence of mood disorders, and a relative loss of grey matter in several brain regions. This study aimed to determine if, compared with controls with and without ischaemic heart disease (IHD), adults with HF show evidence of progressive loss of cerebral grey matter, and whether morphological changes are associated with changes in cognition, depression and anxiety symptoms over a follow-up period of 2 years. METHODS AND RESULTS: This was a 24-month longitudinal study of 19 participants with systolic HF, 43 with IHD, and 45 controls. Subjects were older than 45 years and free of cognitive impairment at the start of follow-up. We acquired magnetic resonance images and used Statistical Parametric Mapping version 8 (SPM8) to investigate changes in the distribution of cerebral grey matter volume over time. We used the Cambridge Cognitive Examination of the Elderly (CAMCOG) and the Hospital Anxiety and Depression Scale (HADS) to assess 2-year changes in cognitive function and mood. Changes in total grey matter volume and cognitive function were similar across the three study groups, but participants with HF showed evidence of increasing severity of anxiety and depressive symptoms. HF was associated with subtle regional loss of grey matter in the right and left thalamus, left caudate, left and right posterior cingulate, left and right parahippocampal gyri, left superior and middle temporal gyri, and right inferior parietal lobule compared with controls and, to a lesser extent, participants with IHD. CONCLUSION: HF and IHD are not associated with a disproportional loss of cerebral grey matter or cognitive decline over 2 years compared with cardiologically healthy controls. Adults with HF experience increasing symptoms of anxiety and depression over 2 years compared with controls, and this increased vulnerability is associated with a relative loss of grey matter in brain regions that are important for the modulation of emotions.


Assuntos
Encéfalo/patologia , Transtornos Cognitivos/psicologia , Insuficiência Cardíaca/psicologia , Isquemia Miocárdica/psicologia , Idoso , Idoso de 80 Anos ou mais , Ansiedade/complicações , Ansiedade/psicologia , Estudos de Casos e Controles , Núcleo Caudado/patologia , Transtornos Cognitivos/complicações , Depressão/complicações , Depressão/psicologia , Feminino , Giro do Cíngulo/patologia , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/patologia , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Isquemia Miocárdica/patologia , Fibras Nervosas Amielínicas/patologia , Testes Neuropsicológicos , Tamanho do Órgão , Giro Para-Hipocampal/patologia , Lobo Parietal/patologia , Lobo Temporal/patologia , Tálamo/patologia
17.
PLoS One ; 8(12): e81658, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24312569

RESUMO

The demonstration that humans can learn to modulate their own brain activity based on feedback of neurophysiological signals opened up exciting opportunities for fundamental and applied neuroscience. Although EEG-based neurofeedback has been long employed both in experimental and clinical investigation, functional MRI (fMRI)-based neurofeedback emerged as a promising method, given its superior spatial resolution and ability to gauge deep cortical and subcortical brain regions. In combination with improved computational approaches, such as pattern recognition analysis (e.g., Support Vector Machines, SVM), fMRI neurofeedback and brain decoding represent key innovations in the field of neuromodulation and functional plasticity. Expansion in this field and its applications critically depend on the existence of freely available, integrated and user-friendly tools for the neuroimaging research community. Here, we introduce FRIEND, a graphic-oriented user-friendly interface package for fMRI neurofeedback and real-time multivoxel pattern decoding. The package integrates routines for image preprocessing in real-time, ROI-based feedback (single-ROI BOLD level and functional connectivity) and brain decoding-based feedback using SVM. FRIEND delivers an intuitive graphic interface with flexible processing pipelines involving optimized procedures embedding widely validated packages, such as FSL and libSVM. In addition, a user-defined visual neurofeedback module allows users to easily design and run fMRI neurofeedback experiments using ROI-based or multivariate classification approaches. FRIEND is open-source and free for non-commercial use. Processing tutorials and extensive documentation are available.


Assuntos
Interfaces Cérebro-Computador , Gráficos por Computador , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Neurorretroalimentação/métodos , Interface Usuário-Computador , Adulto , Mapeamento Encefálico , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Análise Multivariada , Máquina de Vetores de Suporte , Fatores de Tempo
18.
Clin Neurol Neurosurg ; 115(3): 309-16, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22749007

RESUMO

OBJECTIVE: Memory deficit is a frequent cognitive disorder following acquired prefrontal cortex lesions. In the present study, we investigated the brain correlates of a short semantic strategy training and memory performance of patients with distinct prefrontal cortex lesions using fMRI and cognitive tests. METHODS: Twenty-one adult patients with post-acute prefrontal cortex (PFC) lesions, twelve with left dorsolateral PFC (LPFC) and nine with bilateral orbitofrontal cortex (BOFC) were assessed before and after a short cognitive semantic training using a verbal memory encoding paradigm during scanning and neuropsychological tests outside the scanner. RESULTS: After the semantic strategy training both groups of patients showed significant behavioral improvement in verbal memory recall and use of semantic strategies. In the LPFC group, greater activity in left inferior and medial frontal gyrus, precentral gyrus and insula was found after training. For the BOFC group, a greater activation was found in the left parietal cortex, right cingulated and precuneus after training. CONCLUSION: The activation of these specific areas in the memory and executive networks following cognitive training was associated to compensatory brain mechanisms and application of the semantic strategy.


Assuntos
Encéfalo/fisiologia , Transtornos da Memória/reabilitação , Memória/fisiologia , Córtex Pré-Frontal/patologia , Desempenho Psicomotor/fisiologia , Adulto , Encefalopatias/psicologia , Encefalopatias/reabilitação , Encefalopatias/cirurgia , Mapeamento Encefálico , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/cirurgia , Circulação Cerebrovascular , Imagem Ecoplanar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Transtornos da Memória/etiologia , Transtornos da Memória/psicologia , Rememoração Mental , Pessoa de Meia-Idade , Testes Neuropsicológicos , Oxigênio/sangue , Córtex Pré-Frontal/cirurgia , Semântica
19.
PLoS One ; 7(3): e33345, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22413017

RESUMO

BACKGROUND: Elevated total plasma homocysteine (tHcy) has been associated with cognitive impairment, vascular disease and brain atrophy. METHODS: We investigated 150 volunteers to determine if the association between high tHcy and cerebral grey matter volume and cognitive function is independent of cardiovascular disease. RESULTS: Participants with high tHcy (≥15 µmol/L) showed a widespread relative loss of grey matter compared with people with normal tHcy, although differences between the groups were minimal once the analyses were adjusted for age, gender, diabetes, hypertension, smoking and prevalent cardiovascular disease. Individuals with high tHcy had worse cognitive scores across a range of domains and less total grey matter volume, although these differences were not significant in the adjusted models. CONCLUSIONS: Our results suggest that the association between high tHcy and loss of cerebral grey matter volume and decline in cognitive function is largely explained by increasing age and cardiovascular diseases and indicate that the relationship is not causal.


Assuntos
Encéfalo/patologia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/complicações , Transtornos Cognitivos/sangue , Transtornos Cognitivos/complicações , Homocisteína/sangue , Idoso , Idoso de 80 Anos ou mais , Atrofia/sangue , Atrofia/complicações , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
20.
Neurosci Lett ; 457(2): 107-10, 2009 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-19429173

RESUMO

Recent fMRI studies linked subgenual cingulate cortex (SCC) activity with feelings of guilt for acting counter to social values and altruistic donations towards societal causes. We hypothesized that SCC activity across those different tasks was driven by feelings of attachment. In order to investigate this further, we used fMRI to probe the association of empathic concern and strength of SCC activation in response to guilt- and compassion-evoking verbal descriptions of social behaviour. We were able to confirm our prediction that participants with higher empathic concern had increased activity in the SCC in the guilt condition, whereas there was no association for compassion. These results shed new light on the role of the SCC which shows abnormalities in clinical depression.


Assuntos
Mapeamento Encefálico , Emoções/fisiologia , Empatia , Giro do Cíngulo/fisiologia , Individualidade , Adulto , Depressão/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
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