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Background: Low-intensity transcranial focused ultrasound (tFUS) is a brain stimulation approach that holds promise for the treatment of brain-based disorders. Studies in humans have shown that tFUS can successfully modulate perfusion in focal sonication targets, including the amygdala; however, limited research has explored how tFUS impacts large-scale neural networks., Objective: The aim of the current study was to address this gap and examine changes in resting-state connectivity between large-scale network nodes using a randomized, double-blind, within-subjects crossover study design., Methods: Healthy adults ( n =  18) completed two tFUS sessions, 14 days apart. Each session included tFUS of either the right amygdala or the left entorhinal cortex (ErC). The inclusion of two active targets allowed for within-subjects comparisons as a function of the locus of sonication. Resting-state functional magnetic resonance imaging was collected before and after each tFUS session., Results: tFUS altered resting-state functional connectivity (rsFC) within and between rs-network nodes. Pre-to-post sonication of the right amygdala modulated connectivity within nodes of the salience network (SAN) and between nodes of the SAN and the default mode network (DMN) and frontoparietal network (FRP). A decrease in SAN to FPN connectivity was specific to the amygdala target. Pre-to-post sonication of the left ErC modulated connectivity between the dorsal attention network (DAN) and FPN and DMN. An increase in DAN to DMN connectivity was specific to the ErC target., Conclusion: These preliminary findings may suggest that tFUS induces neuroplastic changes beyond the immediate sonication target. Additional studies are needed to determine the long-term stability of these effects., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Gorka, Jimmy, Koning, Phan, Rotstein, Hoang-Dang, Halavi, Spivak, Monti, Reggente, Bookheimer and Kuhn.)

Two service members were diagnosed with PTSD due to military trauma exposure. One presented with the classical manifestation; the other presented with the dissociative subtype. A statistical map revealed anterior localization of insula connectivity in the classical PTSD patient and posterior localization in the dissociative PTSD patient. These differences suggest that dissociative PTSD may be identified, understood, and treated as a disorder related to increased posterior insula connectivity. This double case study provides preliminary evidence for a concrete neuroanatomical discrepancy between insula function in classical and dissociative PTSD that may help explain the emergence of different coping strategies.

(Appeared originally in Brain Stimulation 2020; 13:1805-1812) Reprinted with permission from Elsevier., (Copyright © 2022 by the American Psychiatric Association.)

Background: This study sought to validate the clinical utility of multimodal magnetic resonance imaging (MRI) techniques in the assessment of neurodegenerative disorders. We intended to demonstrate that advanced neuroimaging techniques commonly used in research can effectively be employed in clinical practice to accurately differentiate heathy aging and dementia subtypes., Methods: Twenty patients with dementia of the Alzheimer's type (DAT) and 18 patients with Parkinson's disease dementia (PDD) were identified using gold-standard techniques. Twenty-three healthy, age and sex matched control participants were also recruited. All participants underwent multimodal MRI including T1 structural, diffusion tensor imaging (DTI), arterial spin labeling (ASL), and magnetic resonance spectroscopy (MRS). MRI modalities were evaluated by trained neuroimaging readers and were separately assessed using cross-validated, iterative discriminant function analyses with subsequent feature reduction techniques. In this way, each modality was evaluated for its ability to differentiate patients with dementia from healthy controls as well as to differentiate dementia subtypes., Results: Following individual and group feature reduction, each of the multimodal MRI metrics except MRS successfully differentiated healthy aging from dementia and also demonstrated distinct dementia subtypes. Using the following ten metrics, excellent separation (95.5% accuracy, 92.3% sensitivity; 100.0% specificity) was achieved between healthy aging and neurodegenerative conditions: volume of the left frontal pole, left occipital pole, right posterior superior temporal gyrus, left posterior cingulate gyrus, right planum temporale; perfusion of the left hippocampus and left occipital lobe; fractional anisotropy (FA) of the forceps major and bilateral anterior thalamic radiation. Using volume of the left frontal pole, right posterior superior temporal gyrus, left posterior cingulate gyrus, perfusion of the left hippocampus and left occipital lobe; FA of the forceps major and bilateral anterior thalamic radiation, neurodegenerative subtypes were accurately differentiated as well (87.8% accuracy, 95.2% sensitivity; 85.0% specificity)., Conclusions: Regional volumetrics, DTI metrics, and ASL successfully differentiated dementia patients from controls with sufficient sensitivity to differentiate dementia subtypes. Similarly, feature reduction results suggest that advanced analyses can meaningfully identify brain regions with the most positive predictive value and discriminant validity. Together, these advanced neuroimaging techniques can contribute significantly to diagnosis and treatment planning for individual patients., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/qims-20-1355). Author SEJ, MD is the owner of Synaptec Network, an MRI software analytics company. Authors SB and TK, PhD. are both part-time employees of Synaptec Network. The other authors have no conflicts of interest to declare., (2021 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

Background: Transcranial focused ultrasound (tFUS) is a noninvasive brain stimulation method that may modulate deep brain structures. This study investigates whether sonication of the right anterior thalamus would modulate thermal pain thresholds in healthy individuals., Methods: We enrolled 19 healthy individuals in this three-visit, double-blind, sham-controlled, crossover trial. Participants first underwent a structural MRI scan used solely for tFUS targeting. They then attended two identical experimental tFUS visits (counterbalanced by condition) at least one week apart. Within the MRI scanner, participants received two, 10-min sessions of either active or sham tFUS spread 10 min apart targeting the right anterior thalamus [fundamental frequency: 650 kHz, Pulse repetition frequency: 10 Hz, Pulse Width: 5 ms, Duty Cycle: 5%, Sonication Duration: 30s, Inter-Sonication Interval: 30 s, Number of Sonications: 10, ISPTA. 0 995 mW/cm2, ISPTA. 3 719 mW/cm2, Peak rarefactional pressure 0.72 MPa]. The primary outcome measure was quantitative sensory thresholding (QST), measuring sensory, pain, and tolerance thresholds to a thermal stimulus applied to the left forearm before and after right anterior thalamic tFUS., Results: The right anterior thalamus was accurately sonicated in 17 of the 19 subjects. Thermal pain sensitivity was significantly attenuated after active tFUS. The pre-post x active-sham interaction was significant (F(1,245.95) = 4.03, p = .046). This interaction indicates that in the sham stimulation condition, thermal pain thresholds decreased 1.08 °C (SE = 0.28) pre-post session, but only decreased .51 °C (SE = 0.30) pre-post session in the active stimulation group., Conclusions: Two 10-min sessions of anterior thalamic tFUS induces antinociceptive effects in healthy individuals. Future studies should optimize the parameter space, dose and duration of this effect which may lead to multi-session tFUS interventions for pain disorders., Competing Interests: Declaration of competing interest AB is employed by BrainSonix, which manufactures the ultrasound device. He holds patents in this area. BWB owns minority stake in Bodhi NeuroTech Inc, which manufactures meditation enhancing devices and holds patents in this area. No other authors have any other conflicts., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

A 29-year-old woman presented with head and neck dystonia, as well as functional seizures. The patient was an active military service member with a history of combat-related trauma. Resting blood oxygen level dependent (BOLD) functional MRI (fMRI) scans of the brain demonstrated an increased anterior cingulate component of the salience network and hyper-connectivity between the insula and cingulate. Following neurological and psychiatric evaluation, she was diagnosed with dissociative post-traumatic stress disorder, partially presenting as a functional movement disorder. Inhibitory repetitive transcranial magnetic stimulation (rTMS) was prescribed with the anterior cingulate as the primary target, and supplementary motor and premotor cortices as secondary targets. The treatment was intended to suppress tremors both directly and indirectly. Thirty-six sessions later, her symptoms were in remission, and she returned to active duty. This case demonstrates the potential efficacy of fMRI-guided rTMS in the treatment of dissociative PTSD.

The redox performance of CeO 2 - x nanocrystals (nanoceria) is always accompanied by the switching of cerium oxidation state between Ce 3+ and Ce 4+ . We monitored Ce 3+  → Ce 4+ oxidation of nanoceria stimulated by oxidant in aqueous colloidal solutions controlling the luminescence of Ce 3+ ions located at different distances from nanoceria surface. The observed Ce 3+ luminescence changes indicate that Ce 3+  → Ce 4+ reaction develops inside nanoceria being triggered by the diffusing oxygen originated from the water splitting on oxidized nanoceria surface. We present the first observation of the pronounced oscillations of Ce 3+ luminescence intensity arising from Ce 3+  ↔ Ce 4+ reversible switching. This threshold effect is to be driven by uptaking and releasing oxygen by nanoceria, when the concentration of oxygen vacancies in nanoceria lattice, oxidant concentration in colloidal solution, and temperature reach certain critical values. So, the ability of nanoceria to uptake and release oxygen depending on the environmental redox conditions really makes it the self-sufficient eternal antioxidant.

In experiments in vivo the effect of nanocerium (cerium oxide nanoparticles) on the stability of red blood cells to acid hemolysis, levels of both ROS and RNS generation and H2S pools in plasma and erythrocytes of old rats were investigated. In red blood cells of old rats the proton penetration into the matrix of erythrocytes showed a significant raising and the fate of labile "aging" erythrocytes in old animals compared with adult were up- regulated. These phenomena paralleled with significant up-regulation of ROS and RNS generation. Introduction for 14 days per os to old rats 0.1 mg/kg of nanocerium fully restored resistance of erythrocytes to acid hemolysis by ROS and RNS in both plasma and erythrocytes reduction. Nanocerium decreased the erythrocytes and, conversely, significantly increased the plasma's pools of H2S.