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OBJECTIVE: This study aimed at assessing the alterations in upper limb motor impairment and connectivity between motor areas following the post-stroke delivery of cathodal transcranial direct current stimulation sessions. METHODS: Modifications in the Fugl-Meyer Assessment scores, connectivity between the primary motor cortex of the unaffected and affected hemispheres, and between the primary motor and premotor cortices of the unaffected hemisphere were compared prior to and following six sessions of cathodal transcranial direct current stimulation application in 13 patients (active = 6; sham = 7); this modality targets the primary motor cortex of the unaffected hemisphere early after a stroke. RESULTS: Clinically relevant distinctions in Fugl-Meyer Assessment scores (≥9 points) were observed more frequently in the Sham Group than in the Active Group. Between-group differences in the alterations in Fugl-Meyer Assessment scores were not statistically significant (Mann-Whitney test, p=0.133). ROI-to-ROI correlations between the primary motor cortices of the affected and unaffected hemispheres post-therapeutically increased in 5/6 and 2/7 participants in the Active and Sham Groups, respectively. Between-group differences in modifications in connectivity between the aforementioned areas were not statistically significant. Motor performance enhancements were more frequent in the Sham Group compared to the Active Group. CONCLUSION: The results of this hypothesis-generating investigation suggest that heightened connectivity may not translate into early clinical benefits following a stroke and will be crucial in designing larger cohort studies to explore mechanisms underlying the impacts of this intervention. ClinicalTrials.gov Identifier: NCT02455427.

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ABSTRACT Objective This study aimed at assessing the alterations in upper limb motor impairment and connectivity between motor areas following the post-stroke delivery of cathodal transcranial direct current stimulation sessions. Methods Modifications in the Fugl-Meyer Assessment scores, connectivity between the primary motor cortex of the unaffected and affected hemispheres, and between the primary motor and premotor cortices of the unaffected hemisphere were compared prior to and following six sessions of cathodal transcranial direct current stimulation application in 13 patients (active = 6; sham = 7); this modality targets the primary motor cortex of the unaffected hemisphere early after a stroke. Results Clinically relevant distinctions in Fugl-Meyer Assessment scores (≥9 points) were observed more frequently in the Sham Group than in the Active Group. Between-group differences in the alterations in Fugl-Meyer Assessment scores were not statistically significant (Mann-Whitney test, p=0.133). ROI-to-ROI correlations between the primary motor cortices of the affected and unaffected hemispheres post-therapeutically increased in 5/6 and 2/7 participants in the Active and Sham Groups, respectively. Between-group differences in modifications in connectivity between the aforementioned areas were not statistically significant. Motor performance enhancements were more frequent in the Sham Group compared to the Active Group. Conclusion The results of this hypothesis-generating investigation suggest that heightened connectivity may not translate into early clinical benefits following a stroke and will be crucial in designing larger cohort studies to explore mechanisms underlying the impacts of this intervention. ClinicalTrials.gov Identifier: NCT02455427.

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Objectives: To explore differences in regional cortical morphometric structure between adolescents at risk for depression or with current depression. Methods: We analyzed cross-sectional structural neuroimaging data from a sample of 150 Brazilian adolescents classified as low-risk (LR) (n=50) or high-risk (HR) for depression (n=50) or with current depression (n=50) through a vertex-based approach with measurements of cortical volume (CV), surface area (SA), and cortical thickness (CT). Differences between groups in subcortical volume and in the organization of networks of structural covariance were also explored. Results: No significant differences in brain structure between groups were observed in whole-brain vertex-wise CV, SA, or CT. Also, no significant differences in subcortical volume were observed between risk groups. In relation to the structural covariance network, there was an indication of an increase in the hippocampus betweenness centrality index in the HR group network compared to the LR and current depression group networks. However, this result was only statistically significant when applying false discovery rate correction for nodes within the affective network. Conclusion: In an adolescent sample recruited using an empirically based composite risk score, no major differences in brain structure were detected according to the risk and presence of depression.

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OBJECTIVE: To explore differences in regional cortical morphometric structure between adolescents at risk for depression or with current depression. METHODS: We analyzed cross-sectional structural neuroimaging data from a sample of 150 Brazilian adolescents classified as low-risk (n=50) or high-risk for depression (n=50) or with current depression (n=50) through a vertex-based approach with measurements of cortical volume, surface area and thickness. Differences between groups in subcortical volumes and in the organization of networks of structural covariance were also explored. RESULTS: No significant differences in brain structure between groups were observed in whole-brain vertex-wise cortical volume, surface area or thickness. Also, no significant differences in subcortical volume were observed between risk groups. In relation to the structural covariance network, there was an indication of an increase in the hippocampus betweenness centrality index in the high-risk group network compared to the low-risk and current depression group networks. However, this result was only statistically significant when applying false discovery rate correction for nodes within the affective network. CONCLUSION: In an adolescent sample recruited using an empirically based composite risk score, no major differences in brain structure were detected according to the risk and presence of depression.

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Background: Dual-task paradigms are a known tool to evaluate possible impairments in the motor and cognitive function in patients with multiple sclerosis (MS). A technique to evaluate the cortical function during movement is functional near-infrared spectroscopy (fNIRS). The evaluation of the MS course or its treatment by associating fNIRS with gait measurements may be flexible and low-cost; however, there are no feasibility studies in the literature using these combined techniques in early-stage patients with MS. Objective: To evaluate cortical hemodynamics using fNIRS and gait parameters in patients at early stages of MS and in healthy controls during a dual-task paradigm. Methods: Participants performed cognitive tasks while walking to simulate daily activities. Cortical activation maps and gait variability were used to evaluate differences between 19 healthy controls and 20 patients with MS. Results and conclusion: The results suggest an enhanced cortical activation in the motor planning areas already at the early stages of MS when compared to controls. We have also shown that a systematic analysis of the spatiotemporal gait variability parameters indicates differences in the patient population. The association of cortical and gait parameters may reveal possible compensatory mechanisms related to gait during dual tasking at the early stages of the disease.

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This study evaluated how news with positive and negative content about COVID-19, as well as a relaxation pause, affect the emotional state. We also investigated the association between emotional state and practicing meditation/yoga, physical activity or having a mental disease. For that, a sample of 717 participants, recruited through social media, were randomly assigned to listen to negative or positive news about COVID-19. After that, both groups were guided through a short relaxation pause. Their emotional state was measured before they listened to the audios and after each audio. Mixed linear models were used to evaluate the effects of news group, relaxation pause, mental health and well-being practices. Negative news worsened their emotional state, whereas positive news improved it. A brief relaxation pause improved the effects of negative news content and may mitigate the effects of this valence of information. Practicing physical activity, meditation/yoga was associated with better emotional responses.

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A cause of mental distress during the COVID-19 pandemic is media exposure, which can impact health care professionals (HCPs) who must keep up to date with the statistics and procedures to fight the outbreak. This study aimed to evaluate the effects of listening to negative and positive news about COVID-19 pandemic and a relaxation pause audio. For that, we measured the emotional state through Likert items in a scale developed to assess how anxious, stressed, hopeful, conscious about emotions, irritated, despondent, joyful, optimistic, and preoccupied, he or she was feeling in the moment of evaluation. In an online experiment, an HCPs sample of 245 participants were randomly assigned to either listen to negative or positive news contents about COVID-19. After that, both groups were guided by a relaxation pause activity in which they paid attention to the body and breath. They were assessed before and after listening to each audio. After listening to negative news, participants entered in a more negative emotional state than at baseline (p < 0.001) and compared with participants who listened to positive news (p < 0.001). Both groups improved their emotional state after performing the proposed brief relaxation (p < 0.001). These results show the importance of HCPs being aware and controlling the content of consumed news. A brief relaxation practice can mitigate the negative effects of consuming information with negative content.

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BACKGROUND: Graph theory (GT) is a mathematical field that analyses complex networks that can be applied to neuroimaging to quantify brain's functional systems in Parkinson's disease (PD) and essential tremor (ET). OBJECTIVES: To evaluate the functional connectivity (FC) measured by the global efficiency (GE) of the motor network in PD and compare it to ET and healthy controls (HC), and correlate it to clinical parameters. METHODS: 103 subjects (54PD, 18ET, 31HC) were submitted to structural and functional MRI. A network was designed with regions of interest (ROIs) involved in motor function, and GT was applied to determine its GE. Clinical parameters were analyzed as covariates to estimate the impact of disease severity and medication on GE. RESULTS: GE of the motor circuit was reduced in PD in comparison with HC (p .042). Areas that most contributed to it were left supplementary motor area (SMA) and bilateral postcentral gyrus. Tremor scores correlated positively with GE of the motor network in PD subgroups. For ET, there was an increase in the connectivity of the anterior cerebellar network to the other ROIs of the motor circuit in comparison with PD. CONCLUSIONS: FC measured by the GE of the motor network is diminished in PD in comparison with HC, especially due to decreased connectivity of left SMA and bilateral postcentral gyrus. This finding supports the theory that there is a global impairment of the motor network in PD, and it does not affect just the basal ganglia, but also areas associated with movement modulation. The ET group presented an increased connectivity of the anterior cerebellar network to the other ROIs of the motor circuit when compared to PD, which reinforces what it is known about its role in this pathology.

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Gait initiation is a daily challenge even for healthy individuals as it requires the timely coupling between the automatic anticipatory postural adjustment (APA) and the voluntary step according to the context. Modulation of this motor event has been thought to involve higher level brain control, including cognitive inhibitory circuitries. Despite the known participation of the supplementary motor area (SMA) in the modulation of some parameters of APA, the participation of areas controlling inhibition during gait initiation still needs to be investigated. In this study, the hemodynamic responses of the SMA and dorsolateral prefrontal cortex (DLPFC) were assessed using functional near-infrared spectroscopy (fNIRS) during a gait initiation task under cognitive conflict to select the foot to step (congruent [CON] and incongruent [INC] conditions). The older group (OG) showed worse inhibitory control than the young group (YG) along with more impairments in APA parameters. OG also had a lower amplitude of hemodynamic responses in both areas than YG in the INC. The INC increased the correlation between SMA and DLPFC only in the YG. Aging seems to impair the interaction between the hemodynamic responses of SMA and DLPFC, which influences APA performance in gait initiation under cognitive conflict.

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OBJECTIVE: To estimate coronavirus disease 2019-related information consumption and related implications for health care professionals (medical and nonmedical personnel) during the pandemic. METHODS: A cross-sectional on-line survey was distributed to employees of a major health care institution located in São Paulo, Brazil between April 3 and April 10, 2020. Data were analyzed using descriptive statistics. RESULTS: The sample comprised 2,646 respondents. Most participants (44.4%) reported excessive or almost excessive access to information about the novel coronavirus and 67.6% reported having increased their average time spent on social media. When asked how frequently they consider it was easy to determine the reliability of information, "sometimes" corresponded to 43.2% of the answers in contrast to 14.6% responding "always". Answers related to potential signs of information overload associated with the pandemic indicated that 31% of respondents felt stressed by the amount of information they had to keep up with almost every day or always. Overall, 80.0% of respondents reported having experienced at least one of the following symptoms: headache, eye twitching, restlessness or sleeping difficulty. The frequency of symptoms was higher among participants with a more negative information processing style regarding when dealing with large volumes of information relative to those with a positive information processing style. Likewise, symptoms were more frequently reported by participants who had increased their social media access relative to those reporting reduced access during the pandemic. CONCLUSION: Our survey provides a description of how health professionals consume COVID-19 related information during the pandemic, and suggests that excessive information exposure and high processing demands may impose psychological distress and affect mental health.

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