This study investigated factors associated with aphasia severity at both 2 weeks and 3 months after stroke using demographic and clinical variables, brain diffusion tensor imaging (DTI) parameters, and lesion volume measurements. Patients with left hemisphere stroke were assessed at 2 weeks (n = 68) and at 3 months (n = 20) after stroke. Demographic, clinical, and neuroimaging data were collected; language functions were assessed using the Western Aphasia Battery. For neuroimaging, DTI parameters, including the laterality index (LI) of fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity, mean diffusivity and fibre density (FD) of the arcuate fasciculus (AF), and lesion volume, were measured. Lesion volume, cortical involvement, and the national institutes of Health Stroke Scale score significantly predicted aphasia severity at 2 weeks after stroke, whereas the aphasia quotient and presence of depression during the early subacute stage were significant predictors at 3 months after stroke. According to Pearson correlation, LI-AD and LI-FD were significantly correlated with the aphasia quotient 2 weeks after ischaemic stroke, and the LI-FA was significantly correlated with the aphasia quotient 2 weeks after haemorrhagic stroke, suggesting that the extent and mechanism of AF injuries differ between ischaemic and haemorrhagic strokes. These differences may contribute to aphasia severity. Aphasia arises from the inability to understand and regulate language after injury to certain areas of the brain 1. Approximately 35-40% of adults admitted to hospital because of strokes are diagnosed with aphasia 2. Furthermore, approximately 85% of stroke patients with aphasia recover from the aphasia within 3-6 months after onset; however, some may require additional time for recovery and others may never fully recover 3,4. Accurately predicting the prognoses of patients with aphasia during the early post-stroke stages can be helpful for determining the appropriate timing of discharge and need for institutional help 5. Patients with poor post-stroke auditory comprehension and naming ability (anomia) are more often discharged to an institution rather than to home 6. Factors associated with recovery from aphasia can be divided into non-lesion-and lesion-related factors 7. Non-lesion-related factors include age, sex, handedness, and years of education, whereas lesion-related factors include acute-stage aphasia severity, diagnosed aphasia type, and location and size of any corresponding brain lesions 8-10. Stroke-related variables are robust predictors of recovery; however, patient-related variables have been reported to have minimal or no significant prognostic value 7,9. Recently, newly developed techniques, such as diffusion tensor imaging (DTI), voxel-based lesion symptom mapping, and functional magnetic resonance imaging (MRI), have been used to study the effects of brain lesion locations and sizes on aphasia 11-13. DTI can provide information regarding the degree of damage to and structure of white matter in th...

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Swallowing disorders occur more frequently in older adults. However, the effects of the aging process on neural activation when swallowing are unclear. We aimed to identify neural regions activated during swallowing and evaluate changes in neural activation and neural networks with aging. Using a general linear model (GLM) and independent component (IC) analyses, blood oxygen level-dependent (BOLD) signals were observed in the lateral precentral gyrus, postcentral gyrus, anterior insular cortices, supramarginal gyri, and medial frontal gyrus during swallowing. The right thalamus and anterior cingulate gyri were found to be active areas by GLM and IC analyses, respectively. In the correlational analyses, age was negatively correlated with BOLD signals of the lateral precentral gyri, postcentral gyri, and insular cortices in swallowing tasks. Additionally, correlation analyses between ICs of all participants and age revealed negative correlations in the right supramarginal gyrus, both anterior cingulate cortices, putamen, and cerebellum. In the network analysis, the BOLD signal positively correlated with age in the default mode network (DMN), and was negatively correlated in the lateral precentral gyri, postcentral gyri, and insular cortices. The amplitude of low-frequency fluctuations was significantly decreased in the DMN and increased in swallowing-related areas during swallowing tasks. These results suggest that aging has negative effects on the activation of swallowing-related regions and task-induced deactivation of the DMN. These changes may be used to detect early functional decline during swallowing.

Objective This study aimed to investigate the morphometric differences in the corpus callosum between patients with major depressive disorder (MDD) and healthy controls and analyze their relationship to gray matter changes.Methods Twenty female MDD patients and 21 healthy controls (HCs) were included in the study. To identify the difference in the regional gray matter concentration (GMC), VBM was performed with T1 magnetic resonance imaging. The shape analysis of the corpus callosum was processed. Diffusion tensor imaging (DTI) fiber-tracking was performed to identify the regional tract pathways in the damaged corpus callosal areas.Results In the shape analysis, regional shape contractions in the rostrum and splenium were found in the MDD patients. VBM analysis showed a significantly lower white matter concentration in the genu and splenium, and a significantly lower GMC in the frontal, limbic, insular, and temporal regions of the MDD patients compared to the HCs. In DTI fiber-tracking, the fibers crossing the damaged areas of the genu, rostrum, and splenium were anatomically connected to the areas of lower GMC in MDD patients.Conclusion These findings support that major depressive disorder may be due to disturbances in multiple neuronal circuits, especially those associated with the corpus callosum.

Cerebellar mutism (CM) is a rare neurological condition characterized by lack of speech due to cerebellar lesions. CM is often reported in children. We describe a rare case of CM after spontaneous cerebellar hemorrhage. The patient showed mutism, irritability, decreased spontaneous movements and oropharyngeal apraxia. Diffusion tensor imaging revealed significant volume reduction of medial frontal projection fibers from the corpus callosum. In Tracts Constrained by UnderLying Anatomy (TRACULA) analysis, forceps major and minor and bilateral cingulum-angular bundles were not visualized. Cerebello-frontal pathway reconstructed from the FMRIB Software Library showed continuity of fibers, with decreased number of fibers on qualitative analysis. These results suggest that cerebello-frontal disconnection may be a neuroanatomical mechanism of CM. Damage of brain network between occipital lobe, cingulate and cerebellum caused by hemorrhage may also have role in the mechanism of CM in our case.