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Background A brain-heart interaction has been proposed in Takotsubo syndrome (TTS). Structural changes in the limbic system and hypoconnectivity between certain brain areas in the chronic phase of the disease have been reported, but little is known concerning functional neuroimaging in the acute phase. We hypothesized anatomical and functional changes in the central nervous system and investigated whole-brain volumetric and functional connectivity alterations in the acute phase TTS patients compared to controls. Methods Anatomical and resting-state functional magnetic resonance imaging were performed in postmenopausal females: thirteen in the acute TTS phase and thirteen healthy controls without evidence of coronary artery disease. Voxel-based morphometry and graph theoretical analysis were applied to identify anatomical and functional differences between patients and controls. Results Significantly lower gray matter volumes were found in TTS patients in the right middle frontal gyrus (p = 0.004) and right subcallosal cortex (p = 0.009) compared to healthy controls. When lower threshold was applied, volumetric changes were noted in the right insular cortex (p = 0.0113), the right paracingulate cortex (p = 0.012), left amygdala (p = 0.018), left central opercular cortex (p = 0.017), right (p = 0.013) and left thalamus (p = 0.017), and left cerebral cortex (p = 0.017). Graph analysis revealed significantly (p < 0.01) lower functional connectivity in TTS patients compared to healthy controls, particularly in the connections originating from the right insular cortex, temporal lobes, and precuneus. Conclusion In the acute phase of TTS volumetric changes in frontal regions and the central autonomic network (i.e. insula, anterior cingulate cortex, and amygdala) were noted. In particular, the right insula, associated with sympathetic autonomic tone, had both volumetric and functional changes.

Background: Impairment of odor discrimination (D), identification (I), and threshold (T) are characteristic features of multiple sclerosis (MS). Objective: To identify patterns of gray matter concentration (GMC) associated with different qualities of olfactory function. Methods: Olfactory function (T and combined DI score) was measured by Sniffin’ Sticks-Test over 2 years longitudinally, and T1-weighted 3-T magnetic resonance imaging (MRI) was performed in 37 MS patients and 18 matched healthy controls (HCs). Statistical parametric mapping (SPM) was applied to objectively identify changes of voxel-wise-GMC throughout the entire brain volume and to correlate image parameters with odor function. Results: SPM localized significant GMC decreases in the anterior cingulum as well as temporomesial and frontobasal brain areas of the MS group compared with HCs, and revealed significant correlations between lower DI scores and GMC decreases in the olfactory gyrus, anterior cingulum, temporal regions including the parahippocampus, and putamen. Contrarily, no correlations were found between T and GMC. Patients with disability progression had significantly lower mean temporomesial/putamen GMC (0.782 vs 0.804, p = 0.004) compared to patients without Expanded Disability Status Scale (EDSS) progression. Conclusion: Impairment of DI, but not T is associated with GM atrophy in brain regions related to olfactory function. Further studies are warranted to investigate DI scores and temporomesial/putamen GMC as biomarkers for disability progression.

Background and purposeFunctional connectivity studies revealed alterations within thalamic, salience, and default mode networks in restless legs syndrome patients.MethodsEighty‐two patients with restless legs syndrome (untreated, n = 30; on dopaminergic medication, n = 42; on alpha‐2‐delta ligands as mono‐ or polytherapy combined with dopaminergic medication, n = 10), and 82 individually age‐ and gender‐matched healthy controls were studied with resting‐state functional magnetic resonance imaging. Connectivity of 12 resting‐state networks was investigated with independent component analysis, and network topology was studied with graph methods among 410 brain regions.ResultsPatients with restless legs syndrome showed significantly higher connectivity within salience (p = 0.029), executive (p = 0.001), and cerebellar (p = 0.041) networks, as well as significantly lower (p < 0.05) cerebello‐frontal communication compared to controls. In addition, they had a significantly higher (p < 0.05) clustering coefficient and local efficiency in motor and frontal regions; lower clustering coefficient in the central sulcus; and lower local efficiency in the central opercular cortex, temporal, parieto‐occipital, cuneus, and occipital regions compared to controls. Untreated patients had significantly lower (p < 0.05) cerebello‐parietal communication compared to healthy controls. Connectivity between the thalamus and frontal regions was significantly increased (p < 0.05) in patients on dopaminergic medication compared to untreated patients and controls.ConclusionsNetworks with higher intranetwork connectivity (i.e., salience, executive, cerebellar) and lower cerebello‐frontal connectivity in the restless legs syndrome patients, as well as lower cerebello‐parietal connectivity in untreated patients, correspond to regions associated with attention, response inhibitory control, and processing of sensory information. Intact cerebello‐parietal communication and increased thalamic connectivity to the prefrontal regions in patients on dopaminergic medication suggests a treatment effect on thalamus.

BackgroundThe cognitive function of brain tumor patients is affected during the treatment. There is evidence that gliomas and surgery alter the functional brain connectivity but studies on the longitudinal effects are lacking.MethodsWe acquired longitudinal (pre- and post-radiotherapy) resting-state functional magnetic resonance imaging on three selected glioblastoma patients. These cases were selected to study three models: a lesion involving a functional hub within a central system, a lesion involving a peripheral node within a central system and a lesion involving a peripheral node of a non-central system.ResultsWe found that, as expected, the tumor lesion affects connections in close vicinity, but when the lesion relates to a functional hub, these changes involve long-range connections leading to diverse connectivity profiles pre- and post-radiotherapy. In particular, a global but temporary improvement in the post-radiotherapy connectivity was obtained when treating a lesion close to a network hub, such as the posterior Cingulate Cortex.ConclusionsThis suggests that this node re-establishes communication to nodes further away in the network. Eventually, these observed effects seem to be transient and on the long-term the tumor burden leads to an overall decline of connectivity following the course of the pathology. Furthermore, we obtained that the link between hubs, such as the Supplementary Motor Area and posterior Cingulate Cortex represents an important backbone by means of which within and across network communication is handled: the disruption of this connection seems to imply a strong decrease in the overall connectivity.

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BackgroundGrey matter volume (GMV) decline is a frequent finding in multiple sclerosis (MS), the most common chronic neurological disease in young adults. Increases of GMV were detected in language related brain regions following second language (L2) learning in healthy adults. Effects of L2 learning in people with MS (pwMS) have not been investigated so far.MethodsThis study prospectively evaluated the potential of an eight-week L2 training on grey matter plasticity measured by 3T-MRI, L2 proficiency and health-related quality of life (HRQoL) in people with relapsing-remitting MS (pwMS, n = 11) and healthy, sex- and age-matched controls (HCs; n = 12).ResultsCategorical voxel-based analysis revealed significantly less GMV bilaterally of the insula extending to the temporal pole in pwMS at baseline. Following L2 training, significant increases of GMV were evident in the right hippocampus, parahippocampus and putamen of pwMS and in the left insula of HCs. L2 training resulted in significant improvements of listening comprehension, speaking fluency and vocabulary knowledge in both pwMS and HCs. GMV increases of right hippocampus and parahippocampus significantly correlated with vocabulary knowledge gain and L2 learning was associated with a significant increase of HRQoL in pwMS.ConclusionOur findings demonstrate distinct patterns of GMV increases of language related brain regions in pwMS and HCs and indicate disease-related compensatory cortical and subcortical plasticity to acquire L2 proficiency in pwMS.