RESUMO
BACKGROUND: Resting state magnetic resonance imaging allows studying functionally interconnected brain networks. Here we were aimed to verify functional connectivity between brain networks at rest and its relationship with thalamic microstructure in migraine without aura (MO) patients between attacks. METHODS: Eighteen patients with untreated MO underwent 3 T MRI scans and were compared to a group of 19 healthy volunteers (HV). We used MRI to collect resting state data among two selected resting state networks, identified using group independent component (IC) analysis. Fractional anisotropy (FA) and mean diffusivity (MD) values of bilateral thalami were retrieved from a previous diffusion tensor imaging study on the same subjects and correlated with resting state ICs Z-scores. RESULTS: In comparison to HV, in MO we found significant reduced functional connectivity between the default mode network and the visuo-spatial system. Both HV and migraine patients selected ICs Z-scores correlated negatively with FA values of the thalamus bilaterally. CONCLUSIONS: The present results are the first evidence supporting the hypothesis that an abnormal resting within networks connectivity associated with significant differences in baseline thalamic microstructure could contribute to interictal migraine pathophysiology.
Assuntos
Córtex Cerebral/fisiopatologia , Enxaqueca sem Aura/fisiopatologia , Tálamo/fisiopatologia , Adulto , Anisotropia , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Imagem de Tensor de Difusão , Feminino , Neuroimagem Funcional , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Enxaqueca sem Aura/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Tálamo/diagnóstico por imagemRESUMO
Tourette syndrome (TS) is hypothesised to be caused by an abnormal organization of movement control. The aim of this study was to use functional magnetic resonance imaging to study motor cortex activation in a TS patient. Usual and unusual self-paced voluntary movements were performed. The TS patient displayed supplementary motor area (SMA) activation during both tasks. This activation reflects a continuous use of the SMA to perform the voluntary motor movements required in both tasks. Moreover, the absence of tics during the execution of these voluntary motor tasks suggests that tic activity may be suppressed by additional mental effort.