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Circadian rhythms have been shown in the subthalamic nucleus (STN) in Parkinsons disease (PD), but only a few studies have focused on the globus pallidus internus (GPi). This retrospective study investigates GPi circadian rhythms in a large cohort of subjects with PD (130 recordings from 93 subjects) with GPi activity chronically recorded in their home environment. We found a significant change in GPi activity between daytime and nighttime in most subjects (82.4%), with a reduction in GPi activity at nighttime in 56.2% of recordings and an increase in activity in 26.2%. GPi activity in higher frequency bands ( > 20 Hz) was more likely to decrease at night and in patients taking extended-release levodopa medication. Our results suggest that circadian fluctuations in the GPi vary across individuals and that increased power at night might be due to the reemergence of pathological neural activity. These findings should be considered to ensure successful implementation of adaptive neurostimulation paradigms in the real-world.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by dopaminergic neuron loss, leading to motor and non‐motor symptoms. Early detection before symptom onset is crucial but challenging. This study presents a framework integrating circuit modeling, non‐equilibrium dynamics, and optimization to understand PD pathogenesis and enable precision interventions. Neuronal firing patterns, particularly oscillatory activity, play a critical role in PD pathology. The basal ganglia network, specifically the subthalamic nucleus‐external globus pallidus (STN‐GPe) circuitry, exhibits abnormal activity associated with motor dysfunction. The framework leverages the non‐equilibrium landscape and flux theory to identify key connections generating pathological activity, providing insights into disease progression and potential intervention points. The intricate STN‐GPe interplay is highlighted, shedding light on compensatory mechanisms within this circuitry may initially counteract changes but later contribute to pathological alterations as disease progresses. The framework addresses the need for comprehensive evaluation methods to assess intervention outcomes. Cross‐correlations between state variables provide superior early warning signals compared to traditional indicators relying on critical slowing down. By elucidating compensatory mechanisms and circuit dynamics, the framework contributes to improved management, early detection, risk assessment, and potential prevention/delay of PD development. This pioneering research paves the way for precision medicine in neurodegenerative disorders. [ABSTRACT FROM AUTHOR]

Background and purpose Methods Results Conclusion Several surgical techniques have been used to treat cervical dystonia (CD), however, to date, the optimal surgical technique for CD remains controversial. We therefore conducted the first network meta‐analysis to compare different surgical strategies for CD to inform clinical practice.Electronic databases were searched for surgical strategies for treating CD. The primary outcome was improvement in total Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) score. Subgroup analysis was performed to compare short‐term (< 1 year) and long‐term (≥ 1 year) outcomes. Safety outcomes included surgery‐related adverse events (AEs).A total of 55 trials with 2032 patients employing five surgical strategies were identified, including globus pallidus internus (GPi)/subthalamic nucleus (STN)‐deep brain stimulation (DBS), selective peripheral denervation (SPD), microvascular decompression (MVD) and pallidotomy. All strategies led to significant improvement in total TWSTRS score (mean improvement range 18.65–28.22). GPi‐DBS showed significantly greater enhancement than SPD for the whole dataset (mean difference [MD] 7.03, 95% credible interval [Crl] 1.53–12.56), while both GPi‐DBS (MD 8.05, 95% Crl 2.35–13.80) and STN‐DBS (MD 10.71, 95% Crl 2.22–19.20) exhibited more long‐term improvement than SPD. Regarding safety outcomes, GPi/STN‐DBS and MVD were associated with fewer surgery‐related AEs than SPD (ln odds ratio range −1.68 to −1.41).We conclude that DBS should be the preferred surgical option for CD, and the STN is a promising alternative target choice due to its comparable efficacy with the GPi. However, more direct evidence is still required. [ABSTRACT FROM AUTHOR]

Background: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) and globus pallidus internus (GPi) is an accepted therapy for Parkinson's disease (PD) with disabling motor complications. For elderly patients with poorer cognition and postural instability, GPi has been proposed as the preferable DBS target based on expert opinion, arguing GPi‐DBS may be less complicated by depression, apathy, worsened verbal fluency, and executive dysfunction, resulting in greater improvement in quality of life (QoL). However, data supporting such patient‐tailored approach are lacking. Objectives: The aims were to analyze whether the DBS target influences QoL in a PD cohort and a matched subgroup of frail patients with poor cognitive status and reduced postural stability, and whether other factors affect the QoL outcomes. Methods: In this retrospective study, we analyzed a single‐center cohort of 138 PD patients who received bilateral STN‐DBS (117) or GPi‐DBS (21) using the mentioned approach for target selection. All patients underwent standardized clinical evaluations of motor‐ and nonmotor signs as well as QoL before and 1 year after surgery. Results: DBS of both targets improved motor signs, dyskinesias, and pain. QoL improved without significant difference between the targets, but with a trend for greater improvement across all QoL domains in favor of the STN, even in an STN subgroup matched to the GPi group. Conclusion: Our results contradict the prevailing belief that GPi‐DBS is superior in frail PD patients with cognitive decline and postural instability, questioning the proposed patient‐tailored approach of DBS target selection. Further studies are needed for a data‐driven approach. [ABSTRACT FROM AUTHOR]

Gilles de la Tourette syndrome (GTS) and dystonia (DYS) are both hyperkinetic movement disorders effectively treated by deep brain stimulation (DBS) of the internal part of the globus pallidus (GPi). In this study, we compared single‐neuron activity in the GPi between 18 GTS patients (with an average of 41 cells per patient) and 17 DYS patients (with an average of 54 cells per patient), all of whom underwent bilateral pallidal stimulation surgery, under general anesthesia or while awake at rest. We found no significant differences in GPi neuronal activity characteristics between patients operated on under general anesthesia versus those who were awake, irrespective of their diagnosis (GTS or DYS). We found higher firing rates, firing rate in bursts, pause duration and interspike interval coefficient of variation in GTS patients compared to DYS patients. On the opposite, we found higher number of pauses and bursts frequency in DYS patients. Lastly, we found a higher proportion of GPi oscillatory activities in DYS compared to GTS patients, with predominant activity within the low‐frequency band (theta/alpha) in both patient groups. These findings underscore the complex relationship between the different neuronal discharge characteristic such as oscillatory or bursting activity within the GPi in shaping the clinical phenotypes of hyperkinetic disorders. Further research is warranted to deepen our understanding of how neuronal patterns are transmitted within deep brain structures and to develop strategies aimed at normalizing these pathological activities, by refining DBS techniques to enhance treatment efficacy and individual outcomes. [ABSTRACT FROM AUTHOR]

For decades, the external globus pallidus (GPe) has been viewed as a passive way‐station in the indirect pathway of the cortico‐basal ganglia‐thalamic (CBGT) circuit, sandwiched between striatal inputs and basal ganglia outputs. According to this model, one‐way descending striatal signals in the indirect pathway amplify the suppression of downstream thalamic nuclei by inhibiting GPe activity. Here, we revisit this assumption, in light of new and emerging work on the cellular complexity, connectivity and functional role of the GPe in behaviour. We show how, according to this new circuit‐level logic, the GPe is ideally positioned for relaying ascending and descending control signals within the basal ganglia. Focusing on the problem of inhibitory control, we illustrate how this bidirectional flow of information allows for the integration of reactive and proactive control mechanisms during action selection. Taken together, this new evidence points to the GPe as being a central hub in the CBGT circuit, participating in bidirectional information flow and linking multifaceted control signals to regulate behaviour. [ABSTRACT FROM AUTHOR]

Background Objective Methods Results Conclusion No clinical trials have been reported on the use of focused ultrasound (FUS) for treating cervical dystonia.We aimed to confirm the efficacy and safety of FUS pallidothalamic tractotomy for cervical dystonia.This was a prospective, open‐label, non‐controlled pilot study. The primary outcome was defined as a change in the score for the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) from baseline to 6 months after FUS pallidothalamic tractotomy. The secondary outcomes included a change in the neck scale for the Burke‐Fahn‐Marsden Dystonia Rating Scale (BFMDRS), mood scales including Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Apathy Evaluating Scale (AES), and adverse events. Patients were assessed for TWSTRS, BFMDRS, and adverse events at baseline, 1 week, 1 month, 3 months, and 6 months after treatment. BDI, BAI, and AES were assessed at baseline and 6 months after treatment.Ten patients were enrolled in this study. The mean age of onset of dystonia was 51.6 ± 10.2 years. The TWSTRS at 6 months (29.9 ± 16.0, range: 3–55) was significantly improved by 43.4% (P < 0.001) from baseline. The BFMDRS‐Neck scales at 6 months (4.2 ± 2.8) were significantly improved by 38.2% (P < 0.001) from baseline. The BDI, BAI, and AES at 6 months were improved by 23.2%, 10.9%, and 30.3%, respectively from baseline. Reduced hand dexterity in three patients and weight gain in two patients were confirmed at the last evaluation.This study suggests that FUS pallidothalamic tractotomy may be an effective treatment option for patients with cervical dystonia. © 2024 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Background: There are increasing reports of the misuse of prescription psychostimulants for cognitive enhancement together with recreational cannabis. This raises a concern that chronic use of cannabis high in Δ9-THC may alter the sensitivity to amphetamines. In this exploratory study we hypothesized chronic exposure to Δ9-THC through vaporized cannabis would diminish the central nervous system (CNS) activity of Adderall. Methods: To address this issue we exposed male and female mice to inhaled vaporized cannabis (10.3% Δ9-THC) or placebo for 30 min each day for ten consecutive days. After 24 h, mice were imaged fully awake for changes in BOLD signal following an IP injection of Adderall (60 µg) during the scanning session. After a 2-week washout, without any cannabis or placebo exposure, mice were again imaged and challenged with Adderall during the scanning session. The data were registered to a mouse 3D MRI atlas with 134 brain regions providing sitespecific increases and decreases in global brain activity. Results: Mice exposed to cannabis when compared to placebo showed a decrease in brain activation to Adderall. The blunted Adderall response was characterized by a decrease in positive BOLD signal and increase in negative BOLD. The prefrontal cortex, accumbens, ventral pallidum, caudate/putamen, and thalamus were most affected. After a 2-week wash out there were no significant differences between the cannabis and placebo groups when challenged with Adderall. Summary: This exploratory study shows that short, daily exposures to inhaled cannabis, something equivalent to recreational use, affects the sensitivity to the psychostimulant Adderall. The reduced Adderall effect on brain activity, particularly circuitry associated with dopaminergic signaling raises concerns about escalation in psychostimulant use. [ABSTRACT FROM AUTHOR]

Background and purpose Methods Results Conclusions Disabling dystonia despite optimal medical treatment is common in Wilson disease (WD). No controlled study has evaluated the effect of deep brain stimulation (DBS) on dystonia related to WD. This study was undertaken to evaluate the efficacy of DBS on dystonia related to WD.A meta‐analysis of an N‐of‐1 prospective, randomized, double‐blind, multicenter DBS study was conducted at two French WD reference centers. Main inclusion criteria were patients with WD, stabilized for at least 6 months with significant disability due to dystonia despite optimized medical treatment. The subthalamic nucleus (STN) was targeted for bradykinetic patients with tonic dystonia, and the internal globus pallidus (GPi) was chosen for patients with hyperkinetic dystonia. Each patient underwent two periods of DBS “on” and two periods of DBS “off,” each lasting 4 months. The order of stimulation conditions was randomized. The primary outcome was the change in the Canadian Occupational Performance Measure Performance (COPM‐P) and Satisfaction scores after each 4‐month period. Secondary outcomes were changes in the Burke–Fahn–Marsden Dystonia Rating Scale (BFMDRS) severity and disability scores and Unified Wilson's Disease Rating Scale (UWDRS) scores.Between 12 May 2016 and 7 October 2022, three patients were included. Two patients received bilateral GPi DBS, and one received bilateral STN DBS. There was no change of COPM‐P (p = 0.956), BFMDRS, and UWDRS scores. No serious adverse events were reported.STN or GPi DBS are ineffective on dystonia related to WD. [ABSTRACT FROM AUTHOR]

Background and purpose Methods Results Conclusions This study aimed to investigate the association between iron content in grey matter (GM) nuclei and functional outcome in acute ischaemic stroke (AIS) patients utilizing quantitative susceptibility mapping.Forty AIS patients and 40 age‐, sex‐ and education‐matched healthy controls underwent quantitative susceptibility mapping to assess susceptibility values, which are positively correlated with iron content, in the caudate nucleus, putamen, globus pallidus, thalamus, red nucleus and substantia nigra. The nuclei on the contralateral side were measured in AIS patients to minimize confounding due to oedema or haemorrhage. Functional outcome was determined by the modified Rankin Scale (mRS) score at 3 months after stroke. Poor outcome was defined as mRS >2, whilst a good outcome was defined as ≤2.Susceptibility values were significantly higher in most contralateral GM nuclei in AIS patients than in the corresponding left or right nuclei in healthy controls. AIS patients with poor outcome showed significantly lower susceptibility value than those with good outcome in the contralateral caudate nucleus, but no significant differences were observed in other GM nuclei. Binary logistic regression analysis revealed a significant association between the susceptibility value of the contralateral caudate nucleus and poor outcome after adjustment for confounders (adjusted odds ratio 0.692, 95% confidence interval 0.486–0.986, p = 0.042). Receiver operating characteristic curve analysis showed an acceptable ability of the susceptibility value of the contralateral caudate nucleus to predict poor outcome (area under the curve 0.740, p = 0.013).Lower iron content in the contralateral caudate nucleus was associated with poor functional outcome in AIS patients. [ABSTRACT FROM AUTHOR]

The globus pallidus externus (GPe) is a central component of the basal ganglia circuit that acts as a gatekeeper of cocaine-induced behavioral plasticity. However, the molecular and circuit mechanisms underlying this function are unknown. Here, we show that GPe parvalbumin-positive (GPePV) cells mediate cocaine responses by selectively modulating ventral tegmental area dopamine (VTADA) cells projecting to the dorsomedial striatum (DMS). Interestingly, GPePV cell activity in cocaine-naive mice is correlated with behavioral responses following cocaine, effectively predicting cocaine sensitivity. Expression of the voltage-gated potassium channels KCNQ3 and KCNQ5 that control intrinsic cellular excitability following cocaine was downregulated, contributing to the elevation in GPePV cell excitability. Acutely activating channels containing KCNQ3 and/or KCNQ5 using the small molecule carnosic acid, a key psychoactive component of Salvia rosmarinus (rosemary) extract, reduced GPePV cell excitability and impaired cocaine reward, sensitization, and volitional cocaine intake, indicating its therapeutic potential to counteract psychostimulant use disorder. [Display omitted] • Globus pallidus is part of a 4-node circuit controlling cocaine sensitivity • KCNQ3 and KCNQ5 expression is reduced following cocaine administration • Carnosic acid inhibits GPePV cells through activating KCNQ3/5 heteromers • Carnosic acid reduces cocaine reward, sensitization, and self-administration Tian et al. demonstrate that the activity of cells in the mouse globus pallidus can predict neurophysiological and behavioral responses to cocaine. This discovery leads to the identification of carnosic acid, derived from the ancient medicinal plant rosemary, as a potential therapeutic that reduces cocaine reward and self-administration. [ABSTRACT FROM AUTHOR]

Background Objective Methods Results Conclusions Efficacy of deep brain stimulation (DBS) relies on accurate lead placement as well as optimization of the stimulation parameters. Although clinical software tools are now available, programming still largely relies on a monopolar review, a tedious process for both patients and programmers.This study investigates the safety and feasibility of prospective automated connectomic DBS programming (automated connectomic programming [ACP]), focusing on the recruitment of specific white matter pathways.After DBS implantation, a detailed connectomic DBS model in patient‐specific space was developed for each study participant. A driving‐force model was used to quantify pathway recruitment across 2400 different DBS settings. Optimization algorithms maximized recruitment of therapeutic pathways while minimizing recruitment of side‐effect pathways. Thirteen subjects were enrolled in two study phases that compared DBS settings derived from ACP to standard clinical DBS settings.Nine patients underwent reprogramming with ACP (5 globus pallidus interna [GPi], 4 subthalamic nucleus [STN]). Four patients underwent initial programming with ACP (3 GPi, 1 STN). All patients tolerated ACP without persistent side effects. In the reprogramming cohort, 3 patients preferred their ACP program, and 1 patient felt it was comparable to their clinical program. Unified Parkinson's Disease Rating Scale, Part III, scores for the initial ACP cohort (3 GPi, 1 STN) improved by an average of 43.5% (40.4–52.6 ± 5.6%).ACP appeared clinically safe and feasible. It provided reasonable motor improvement, which can be further optimized with subsequent clinical adjustment. Additional investigation is required to refine the optimization algorithm and to quantify the clinical benefit of ACP in a larger cohort. © 2024 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Here, we report a magnetogenetic system, based on a single anti-ferritin nanobody-TRPV1 receptor fusion protein, which regulated neuronal activity when exposed to magnetic fields. Adeno-associated virus (AAV)-mediated delivery of a floxed nanobody-TRPV1 into the striatum of adenosine-2a receptor-Cre drivers resulted in motor freezing when placed in a magnetic resonance imaging machine or adjacent to a transcranial magnetic stimulation device. Functional imaging and fiber photometry confirmed activation in response to magnetic fields. Expression of the same construct in the striatum of wild-type mice along with a second injection of an AAVretro expressing Cre into the globus pallidus led to similar circuit specificity and motor responses. Last, a mutation was generated to gate chloride and inhibit neuronal activity. Expression of this variant in the subthalamic nucleus in PitX2-Cre parkinsonian mice resulted in reduced c-fos expression and motor rotational behavior. These data demonstrate that magnetogenetic constructs can bidirectionally regulate activity of specific neuronal circuits noninvasively in vivo using clinically available devices. [ABSTRACT FROM AUTHOR]

Background: Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant inherited vascular disorder that can involve multiple organs, thus can be associated with so many clinical departments that proper screening and diagnosis of HHT are needed for providing better management of both patients and their family members. Case presentation: We present a 58-year-old female patient with recurrent paradoxical brain embolism due to HHT. She received aspirin therapy and underwent pulmonary arteriovenous malformation embolization, recovering well and discharged 3 days postoperatively. Though ischemic stroke caused by HHT-induced vascular disorders has been reported, our patient presented with both recurrent paradoxical brain embolisms and radiologic findings of bilateral globus pallidus manganese deposition at the same time, a combination rarely reported. We also review the literature on the clinical features and management of HHT for prompt diagnosis of this genetic disease behind paradoxical embolism. Conclusions: When patients with ischemic stroke, especially recurrent ischemic stroke, have combined arteriovenous malformations (AVMs) in single or multiple organs, or clues for AVMs like manganese deposition in globus pallidus, genetic diseases such as HHT may be the reason for ischemic stroke and shouldn't be missed in the evaluation of embolic sources. [ABSTRACT FROM AUTHOR]

Tourette's syndrome is a neuropsychiatric disorder characterized by formidable motor and vocal tics. Many individuals also present with comorbid neuropsychiatric conditions. Though patients often benefit from pharmacological and behavioral therapies, a subset of individuals develop severe, treatment-resistant symptoms that might necessitate more invasive interventions, such as Deep Brain Stimulation (DBS). DBS, particularly targeting regions like the globus pallidus internus (GPi) and the centromedian-parafascicular complex (CM-Pf) of the thalamus, has demonstrated effectiveness in reducing tic severity and improving quality of life. This review outlines the mechanism, clinical efficacy, and long-term outcome of DBS in TS. Results from clinical studies reveal significant reductions in tics. However, success with DBS is variable depending on a number of factors, including target selection and electrode placement. The use of DBS has ethical considerations, which include risks to the surgical procedure, the need for full and complete informed consent, and questions about the implications of such treatment on cognitive and emotional growth. Long-term follow-up will be required to ensure appropriate patient outcomes and complication management. Additional research and ethical debate will be needed with advancing DBS technology to ensure responsible and equitable treatment. This paper narratively summarizes the surgical options available for TS, with a focus on the current status of DBS in the management of the disease. [ABSTRACT FROM AUTHOR]

Background/Objectives: This systematic review and meta‐analysis aimed to investigate the role of magnetic susceptibility (χ) in deep gray matter (DGM) structures, including the putamen (PUT), globus pallidus (GP), caudate nucleus (CN), and thalamus, in the most common types of multiple sclerosis (MS) and relapsing‐remitting MS (RRMS), using quantitative susceptibility mapping (QSM). Methods: The literature was systematically reviewed up to November 2023, adhering to PRISMA guidelines. This study was conducted using a random‐effects model to calculate the standardized mean difference (SMD) in QSM values between patients with RRMS and healthy controls (HCs). Publication bias and risk of bias were also assessed. Results: Nine studies involving 1074 RRMS patients with RRMS and 640 HCs were included in the meta‐analysis. The results showed significantly higher QSM (χ) values in the PUT (SMD = 0.40, 95% confidence interval [CI] = 0.22–0.59, p =.000), GP (SMD = 0.60, 95% CI = 0.50–0.70, p =.00), and CN (SMD = 0.40, 95% CI = 0.15–0.66, p =.005) of RRMS patients compared to HCs. However, there were no significant differences in the QSM values in the thalamus between patients with RRMS and HCs (SMD = −0.33, 95% CI −0.67–0.01, p =.026). Age‐ and sex‐based subgroup analysis demonstrated that younger patients (< 40 years) in the PUT, GP, and CN groups and larger male populations (> 25%) in the PUT and GP groups had more significant χ. Interestingly, thalamic QSM values were found to decrease in RRMS patients over 40 years of age and in higher male populations. Sex‐based subgroup analysis indicated higher iron levels in the PUT and GP of RRMS patients regardless of sex. QSM values were higher in certain brain regions (PUT, GP, and CN) during the early stages (disease duration < 9.6 years) of RRMS, but lower in the thalamus during the later stages (disease duration > 9.6 years) than HCs. Discussion/Conclusion: QSM may serve as a biomarker for understanding χ value alterations such as iron dysregulation and its contribution to neurodegeneration in RRMS, especially in the basal ganglia nuclei including PUT, GP, and CN. [ABSTRACT FROM AUTHOR]

Substantial evidence highlights the role of the cerebellum in the pathophysiology of tremor in essential tremor (ET), although its potential involvement in altered movement execution in this condition remains unclear. This study aims to explore potential correlations between the cerebellum and basal ganglia functional connectivity and voluntary movement execution abnormalities in ET, objectively assessed with kinematic techniques. A total of 20 patients diagnosed with ET and 18 healthy subjects were enrolled in this study. Tremor and repetitive finger tapping were recorded using an optoelectronic kinematic system. All participants underwent comprehensive 3T-MRI examinations, including 3D-T1 and blood-oxygen-level dependent (BOLD) sequences during resting state. Morphometric analysis was conducted on the 3D-T1 images, while a seed-based analysis was performed to investigate the resting-state functional connectivity (rsFC) of dorsal and ventral portions of the dentate nucleus and the external and internal segments of the globus pallidus. Finally, potential correlations between rsFC alterations in patients and clinical as well as kinematic scores were assessed. Finger tapping movements were slower in ET than in healthy subjects. Compared to healthy subjects, patients with ET exhibited altered FC of both dentate and globus pallidus with cerebellar, basal ganglia, and cortical areas. Interestingly, both dentate and pallidal FC exhibited positive correlations with movement velocity in patients, differently from that we observed in healthy subjects, indicating the higher the FC, the faster the finger tapping. The findings of this study indicate the possible role of both cerebellum and basal ganglia in the pathophysiology of altered voluntary movement execution in patients with ET. [ABSTRACT FROM AUTHOR]

Background: The complexities of unilateral dystonia have led to exploring simultaneous (dual) globus pallidus internus (GPi) and motor ventral thalamus (Vim/Vop) deep brain stimulation (DBS), yet detailed assessments are lacking. Objectives: To assess the efficacy of GPi, Vim/Vop, and dual DBS in unilateral dystonia. Methods: Three patients with unilateral dystonia (two idiopathic, one acquired), implanted with two DBS electrodes targeting ipsilateral Vim/Vop and GPi, were included. Three stimulation modalities were assessed. First, one electrode was activated, then the other, and finally, both electrodes were activated simultaneously. Results: DBS yielded substantial symptomatic reductions in all three evaluated stimulation modalities. Patients exhibited varying responses regarding quality‐of‐life and depressive symptoms. Treatment satisfaction didn't align with clinical improvements, potentially affected by unrealistic expectations. Conclusions: This study contributes critical insights into GPi, Vim/Vop and simultaneous stimulation for unilateral dystonia. The safety of the procedure underscores the promise of this approach. [ABSTRACT FROM AUTHOR]

The recently discovered methodologies to cultivate and genetically manipulate Treponema pallidum subsp. pallidum (T. pallidum) have significantly helped syphilis research, allowing the in vitro evaluation of antibiotic efficacy, performance of controlled studies to assess differential treponemal gene expression, and generation of loss‐of‐function mutants to evaluate the contribution of specific genetic loci to T. pallidum virulence. Building on this progress, we engineered the T. pallidum SS14 strain to express a red‐shifted green fluorescent protein (GFP) and Sf1Ep cells to express mCherry and blue fluorescent protein (BFP) for enhanced visualization. These new resources improve microscopy‐ and cell sorting–based applications for T. pallidum, better capturing the physical interaction between the host and pathogen, among other possibilities. Continued efforts to develop and share new tools and resources are required to help our overall knowledge of T. pallidum biology and syphilis pathogenesis reach that of other bacterial pathogens, including spirochetes. [ABSTRACT FROM AUTHOR]

Leukodystrophies are rare genetic white matter disorders that have been regarded as mainly occurring in childhood. This perception has been altered in recent years, as a growing number of leukodystrophies have been described as having an onset in adulthood. Still, many adult patients presenting with white matter changes remain without a specific molecular diagnosis. We describe a novel adult onset leukodystrophy in 16 patients from eight families carrying one of four different stop-gain or frameshift dominant variants in the CST3 gene. Clinical and radiological features differ markedly from the previously described Icelandic cerebral amyloid angiopathy found in patients carrying p.Leu68Asn substitution in CST3. The clinical phenotype consists of recurrent episodes of hemiplegic migraine associated with transient unilateral focal deficits and slowly progressing motor symptoms and cognitive decline in mid to older adult ages. In addition, in some cases acute onset clinical deterioration led to a prolonged episode with reduced consciousness and even early death. Radiologically, pathognomonic changes are found at typical predilection sites involving the deep cerebral white matter sparing a periventricular and directly subcortical rim, the middle blade of corpus callosum, posterior limb of the internal capsule, middle cerebellar peduncles, cerebral peduncles and specifically the globus pallidus. Histopathologic characterization in two autopsy cases did not reveal angiopathy, but instead micro- to macrocystic degeneration of the white matter. Astrocytes were activated at early stages and later displayed severe degeneration and loss. In addition, despite the loss of myelin, elevated numbers of partly apoptotic oligodendrocytes were observed. A structural comparison of the variants in CST3 suggests that specific truncations of cystatin C result in an abnormal function, possibly by rendering the protein more prone to aggregation. Future studies are required to confirm the assumed effect on the protein and to determine pathophysiologic downstream events at the cellular level. [ABSTRACT FROM AUTHOR]

Background: Deep gray matter (DGM) atrophy and lesions are found in multiple sclerosis (MS). Objective: To optimize automated segmentation for 7 T DGM volumetrics and assess sensitivity to atrophy and relationship to DGM lesions and disability in relapsing–remitting (RR) MS. Methods: 30 RRMS subjects [mean age 44.0 years, median Expanded Disability Status Scale (EDSS) score 2] and 14 healthy controls underwent 7 T MRI with 3D magnetization-prepared 2 rapid gradient-echoes (MP2RAGE) and fluid-attenuated inversion recovery. Customizing an automated pipeline to assess DGM structure volumes required pre-processing combining two MP2RAGE inversion times and uniform T1 images, and noise-suppressed reconstruction. DGM volumes were normalized. Brain DGM lesions and white matter T2 lesion volume (T2LV) were expert-quantified. Spearman correlations and Wilcoxon rank-sum tests were assessed. Results: DGM lesions were found in 77% (n = 23) of MS subjects and no controls, with thalamic lesions most prevalent (73%). An average of 3.6 DGM lesions was found per person with MS. Total DGM volumes were lower in MS vs. controls (p = 0.034), varying by region, most pronounced in the caudate (p = 0.008). DGM volumes inversely correlated with EDSS (total DGM: r = – 0.45, p = 0.014; globus pallidus: r = – 0.42, p = 0.023; putamen: r = – 0.44, p = 0.016; caudate: r = – 0.37, p = 0.047) and T2LV (total DGM: r = – 0.53, p = 0.003; putamen: r = – 0.40, p = 0.030; thalamus: r = – 0.63, p < 0.001). DGM atrophy was most closely linked to disability among all MRI measures. Thalamic lesion volume correlated inversely with thalamic volume (r = – 0.38, p = 0.045). Conclusion: 7 T MRI shows a link between DGM atrophy and both white matter lesions and physical disability in RRMS. Thalamic lesions are associated with thalamic atrophy. [ABSTRACT FROM AUTHOR]

Background: Midline Tremor is defined as an isolated or combined tremor that affects the neck, trunk, jaw, tongue, and/or voice and could be part of Essential Tremor (ET), or dystonic tremor. The clinical efficacy of deep brain stimulation for Midline Tremor has been rarely reported. The Ventral Intermediate Nucleus and Globus Pallidus Internus are the preferred targets, but with variable outcomes. Thalamic Ventral-Oralis (VO) complex and Zona Incerta (ZI) are emerging targets for tremor control in various etiologies. Objective: To report on neuroradiological, neurophysiological targeting and long-term efficacy of thalamic Ventral-Oralis complex and Zona Incerta deep brain stimulation in Midline Tremor. Methods: Three patients (two males and one female) with Midline Tremor in dystonic syndromes were recruited for this open-label study. Clinical, surgical, neurophysiological intraoperative testing and long-term follow-up data are reported. Results: Intraoperative testing and reconstruction of volume of tissue activated confirmed the position of the electrodes in the area stimulated between the thalamic Ventral-Oralis complex and Zona Incerta in all patients. All three patients showed optimal control of both tremor and dystonic features at short-term (6 months) and long-term follow-up (up to 6 years). No adverse events occurred. Conclusion: In the syndromes of Midline Tremor of various origins, the best target for DBS might be difficult to identify. Our results showed that thalamic Ventral-Oralis complex/Zona Incerta may be a viable and safe option even in specific forms of tremor with axial distribution. [ABSTRACT FROM AUTHOR]

Purpose: Due to brain shift during bilateral deep brain stimulation (DBS) surgery, placement of the second electrode may be subjected to more error than that of the first electrode. The authors aimed to investigate the accuracy of second electrode placement in this setting. Materials and methods: Fifty-five patients with Parkinson's disease who underwent bilateral DBS surgery (110 electrodes) were retrospectively evaluated. The targets were subthalamic nucleus (STN) and globus pallidus interna (GPi) in 40 and 15 cases, respectively. Preoperative planning and postoperative electrode images were co-registered to compare the error margin between the two sides. Results: There is a statistically significant difference in the directional axis error along the y axis only when comparing each laterality (posterior 0.04 ± 1.21 mm vs anterior 0.41 ± 1.07 mm, p = 0.006). There is no significant difference of other error parameters, final track location, and number of microelectrode recording passes between the two sides. In a subgroup analysis, there is a significant difference in directional axis error along the y axis only in the STN subgroup (posterior 0.40 ± 1.05 mm vs anterior 0.18 ± 1.04 mm, p = 0.003). Conclusion: Although a statistically significant difference in directional axis error along the y axis was found between first and second electrode placements in the STN group but not in the GPi group, its magnitude is well below the clinically significant threshold. [ABSTRACT FROM AUTHOR]

Dystonia is a hyperkinetic movement disorder that has been associated with an imbalance towards the direct pathway between striatum and internal pallidum, but the neuronal underpinnings of this abnormal basal ganglia pathway activity remain unknown. Here, we report invasive recordings from ten dystonia patients via deep brain stimulation electrodes that allow for parallel recordings of several basal ganglia nuclei, namely the striatum, external and internal pallidum, that all displayed activity in the low frequency band (3–12 Hz). In addition to a correlation with low-frequency activity in the internal pallidum (R = 0.88, P = 0.001), we demonstrate that dystonic symptoms correlate specifically with low-frequency coupling between striatum and internal pallidum (R = 0.75, P = 0.009). This points towards a pathophysiological role of the direct striato-pallidal pathway in dystonia that is conveyed via coupling in the enhanced low-frequency band. Our study provides a mechanistic insight into the pathophysiology of dystonia by revealing a link between symptom severity and frequency-specific coupling of distinct basal ganglia pathways. The underpinnings of a supposed basal ganglia pathway imbalance in dystonia are unknown. Here, the authors unveil exaggerated low frequency coupling in the direct striato-pallidal pathway to reflect dystonic symptoms, which could potentially be used as target for neuromodulation strategies. [ABSTRACT FROM AUTHOR]

Many neurons in the mammalian brain show pacemaking activity: rhythmic generation of action potentials in the absence of sensory or synaptic input. Slow pacemaking of neurons releasing modulatory transmitters is easy to rationalize. More surprisingly, many neurons in the motor system also show pacemaking activity, often rapid, including cerebellar Purkinje neurons that fire spontaneously at 20–100 Hz, as well as key neurons in the basal ganglia, including subthalamic nucleus neurons and globus pallidus neurons. Although the spontaneous rhythmic firing of pacemaking neurons is phenomenologically similar to cardiac pacemaking, the underlying ionic mechanism in most neurons is quite different than for cardiac pacemaking. Few spontaneously active neurons rely on HCN ‘pacemaker’ channels for their activity. Most commonly, a central element is ‘persistent’ sodium current, steady‐state subthreshold current carried by the same voltage‐dependent sodium channels that underlie fast action potentials. Persistent sodium current is a steeply voltage‐dependent current with a midpoint near −60 mV, which results in regenerative spontaneous depolarization once it produces a net inward current when summed with all other background currents, often at voltages as negative as −70 mV. This ‘engine’ of pacemaking is present in almost all neurons and must be held in check in non‐pacemaking neurons by sufficiently large competing outward currents from background potassium channels. The intrinsic propensity of neurons to fire spontaneously underlies key normal functions such as respiration and generates the complex background oscillatory circuits revealed in EEGs, but can also produce out‐of‐control oscillations of overall brain function in epilepsy, ataxia and tremor. [ABSTRACT FROM AUTHOR]

Aim Method Results Interpretation To address substantial gaps in the literature on neuroanatomical variations in females with fragile X syndrome (FXS).Surface‐based modeling techniques were applied to the magnetic resonance imaging of 45 females with FXS (mean age = 10 years 9 months, range 6 years–16 years 4 months, SD = 2 years 9 months) and 33 age‐matched and developmentally matched females without FXS to elucidate differences in cortical gray matter volume, surface area, and thickness. Gray matter volumes in subcortical regions were examined to ascertain differences in subcortical volume.In females with FXS, cortical volume was greater bilaterally in the occipital pole and smaller in the right postcentral gyrus. Seven regions demonstrated lower surface area in participants with FXS, while cortical thickness was significantly greater over the posterior and medial surfaces in the group with FXS. Subcortical region of interest analyses demonstrated greater volume in the caudate nucleus, globus pallidus, and nucleus accumbens in the group with FXS. Global gray matter volume, pial thickness, and surface area were associated with behavioral outcomes in the group with FXS but not in the comparison group.Females with FXS demonstrated unique cortical and subcortical gray matter anatomy relative to a matched comparison group. These findings may be relevant to the pathogenesis of the FXS behavioral phenotype and provide insights into behavioral interventions targeted to this population. [ABSTRACT FROM AUTHOR]

Introduction: Sites associated with gadolinium (Gd) deposition in the brain (e.g., the globus pallidus) are known to contain high concentrations of ferric iron. There is considerable debate over the mechanism of Gd deposition in the brain. The role of iron transport mechanisms in Gd deposition has not been determined. Thus, we seek to identify if Gd deposition can be controlled by modifying iron exposure. Methods: Female Sprague-Dawley rats were given diets with controlled iron levels at 2-6 ppm, 6 ppt (20 g/kg Fe carbonyl) or 48 ppm for 3 weeks to induce iron deficiency, overload or normalcy. They were kept on those diets while receiving a cumulative 10 mmol/kg dose of gadodiamide intravenously over 2 weeks, then left to washout gadodiamide for 3 days or 3 weeks before tissues were harvested. Gd concentrations in tissues were analyzed by ICP-MS. Results: There were no significant effect of dietary iron and total Gd concentrations in the organs, but there was a significant effect of iron status on Gd distribution in the brain. For the 3-week washout cohort, there was a nonsignificant trend of increasing total brain deposition and decreasing dietary iron, and about 4-fold more Gd in the olfactory bulbs of the low iron group compared to the other groups. Significant brain accumulation was observed in the low iron group total brain Gd in the 3-week washout group relative to the 3-day washout group and no accumulation was observed in other tissues. There was a strong negative correlation between femur Gd concentrations and concentrations in other organs when stratifying by dietary iron. Discussion: Gd brain deposition from linear Gd-based contrast agents (GBCAs) are dependent upon iron status, likely through variable transferrin saturation. This iron dependence appears to be associated with redistribution of peripheral deposited Gd (e.g., in the bone) into the brain. [ABSTRACT FROM AUTHOR]

In progressive supranuclear palsy (PSP), subcortical tau and cortical perfusion can be assessed using the tracer [18F]PI-2620. We investigated if subcortical tau (globus pallidus internus, dentate nucleus) and frontal/limbic perfusion correlate in a cohort of 32 PSP patients. Tau in subcortical regions showed significant negative correlation with perfusion in limbic cortex. Perfusion in frontal regions was negatively associated with tau in both subcortical regions, but the significance threshold was only passed for the dentate nucleus. A reason could be a diaschisis-like phenomenon; that is, subcortical tau could lead to reduced connectivity to frontal regions and, thereby, to decreased perfusion. Plain Language Summary: In a study of 32 patients with progressive supranuclear palsy (PSP), we used a molecular imaging tracer called [18F]PI-2620 to measure two things: the presence of a protein called tau in deep brain areas (specifically, the globus pallidus internus and dentate nucleus) and the function of the brain's cortex by assessing blood flow (perfusion). We found that higher amounts of tau in these deep brain areas were associated with reduced blood flow in the limbic cortex, which is involved in emotion regulation. Also, the frontal areas of the brain showed reduced blood flow related to tau in these deep brain regions. However, this connection was statistically significant only for the dentate nucleus. This study suggests that the buildup of tau protein in deeper brain areas can disrupt function in parts of the brain's cortex, highlighting the damaging role of tau in PSP. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) of the internal segment of the globus pallidus (GPi) can markedly reduce muscle rigidity in people with Parkinson's disease (PD); however, the mechanisms mediating this effect are poorly understood. Computational modeling of DBS provides a method to estimate the relative contributions of neural pathway activations to changes in outcomes. In this study, we generated subject-specific biophysical models of GPi DBS (derived from individual 7-T MRI), including pallidal efferent, putamenal efferent, and internal capsule pathways, to investigate how activation of neural pathways contributed to changes in forearm rigidity in PD. Ten individuals (17 arms) were tested off medication under four conditions: off stimulation, on clinically optimized stimulation, and on stimulation specifically targeting the dorsal GPi or ventral GPi. Quantitative measures of forearm rigidity, with and without a contralateral activation maneuver, were obtained with a robotic manipulandum. Clinically optimized GPi DBS settings significantly reduced forearm rigidity (P < 0.001), which aligned with GPi efferent fiber activation. The model demonstrated that GPi efferent axons could be activated at any location along the GPi dorsal-ventral axis. These results provide evidence that rigidity reduction produced by GPi DBS is mediated by preferential activation of GPi efferents to the thalamus, likely leading to a reduction in excitability of the muscle stretch reflex via overdriving pallidofugal output. NEW & NOTEWORTHY: Subject-specific computational models of pallidal deep brain stimulation, in conjunction with quantitative measures of forearm rigidity, were used to examine the neural pathways mediating stimulation-induced changes in rigidity in people with Parkinson's disease. The model uniquely included internal, efferent and adjacent pathways of the basal ganglia. The results demonstrate that reductions in rigidity evoked by deep brain stimulation were principally mediated by the activation of globus pallidus internus efferent pathways. [ABSTRACT FROM AUTHOR]

Background: Juvenile myoclonic epilepsy (JME) is a common adolescent epilepsy characterized by myoclonic, generalized tonic–clonic, and sometimes absence seizures. Prognosis varies, with many patients experiencing relapse despite pharmacological treatment. Recent advances in imaging and artificial intelligence suggest that combining microstructural brain changes with traditional clinical variables can enhance potential prognostic biomarkers identification. Methods: A retrospective study was conducted on patients with JME at the Severance Hospital, analyzing clinical variables and magnetic resonance imaging (MRI) data. Machine learning models were developed to predict prognosis using clinical and radiological features. Results: The study utilized six machine learning models, with the XGBoost model demonstrating the highest predictive accuracy (AUROC 0.700). Combining clinical and MRI data outperformed models using either type of data alone. The key features identified through a Shapley additive explanation analysis included the volumes of the left cerebellum white matter, right thalamus, and left globus pallidus. Conclusions: This study demonstrated that integrating clinical and radiological data enhances the predictive accuracy of JME prognosis. Combining these neuroanatomical features with clinical variables provided a robust prediction of JME prognosis, highlighting the importance of integrating multimodal data for accurate prognosis. [ABSTRACT FROM AUTHOR]

Purpose: [18F]PI-2620 positron emission tomography (PET) detects misfolded tau in progressive supranuclear palsy (PSP) and Alzheimer's disease (AD). We questioned the feasibility and value of absolute [18F]PI-2620 PET quantification for assessing tau by regional distribution volumes (VT). Here, arterial input functions (AIF) represent the gold standard, but cannot be applied in routine clinical practice, whereas image-derived input functions (IDIF) represent a non-invasive alternative. We aimed to validate IDIF against AIF and we evaluated the potential to discriminate patients with PSP and AD from healthy controls by non-invasive quantification of [18F] PET. Methods: In the first part of the study, we validated AIF derived from radial artery whole blood against IDIF by investigating 20 subjects (ten controls and ten patients). IDIF were generated by manual extraction of the carotid artery using the average and the five highest (max5) voxel intensity values and by automated extraction of the carotid artery using the average and the maximum voxel intensity value. In the second part of the study, IDIF quantification using the IDIF with the closest match to the AIF was transferred to group comparison of a large independent cohort of 40 subjects (15 healthy controls, 15 PSP patients and 10 AD patients). We compared VT and VT ratios, both calculated by Logan plots, with distribution volume (DV) ratios using simplified reference tissue modelling and standardized uptake value (SUV) ratios. Results: AIF and IDIF showed highly correlated input curves for all applied IDIF extraction methods (0.78 < r < 0.83, all p < 0.0001; area under the curves (AUC): 0.73 < r ≤ 0.82, all p ≤ 0.0003). Regarding the VT values, correlations were mainly found between those generated by the AIF and by the IDIF methods using the maximum voxel intensity values. Lowest relative differences (RD) were observed by applying the manual method using the five highest voxel intensity values (max5) (AIF vs. IDIF manual, avg: RD = -82%; AIF vs. IDIF automated, avg: RD = -86%; AIF vs. IDIF manual, max5: RD = -6%; AIF vs. IDIF automated, max: RD = -26%). Regional VT values revealed considerable variance at group level, which was strongly reduced upon scaling by the inferior cerebellum. The resulting VT ratio values were adequate to detect group differences between patients with PSP or AD and healthy controls (HC) (PSP target region (globus pallidus): HC vs. PSP vs. AD: 1.18 vs. 1.32 vs. 1.16; AD target region (Braak region I): HC vs. PSP vs. AD: 1.00 vs. 1.00 vs. 1.22). VT ratios and DV ratios outperformed SUV ratios and VT in detecting differences between PSP and healthy controls, whereas all quantification approaches performed similarly in comparing AD and healthy controls. Conclusion: Blood-free IDIF is a promising approach for quantification of [18F]PI-2620 PET, serving as correlating surrogate for invasive continuous arterial blood sampling. Regional [18F]PI-2620 VT show large variance, in contrast to regional [18F]PI-2620 VT ratios scaled with the inferior cerebellum, which are appropriate for discriminating PSP, AD and healthy controls. DV ratios obtained by simplified reference tissue modeling are similarly suitable for this purpose. [ABSTRACT FROM AUTHOR]

This study compared brain glucose metabolism using FDG-PET in the caudate nucleus, putamen, globus pallidus, thalamus, and dorsolateral prefrontal cortex (DLPFC) among patients with Long COVID, patients with fatigue, people with multiple sclerosis (PwMS) patients with fatigue, and COVID recovered controls. PwMS exhibited greater hypometabolism compared to long COVID patients with fatigue and the COVID recovered control group in all studied brain areas except the globus pallidus (effect size range 0.7–1.5). The results showed no significant differences in glucose metabolism between patients with Long COVID and the COVID recovered control group in these regions. These findings suggest that long COVID fatigue may involve non-CNS systems, neurotransmitter imbalances, or psychological factors not captured by FDG-PET, while MS-related fatigue is associated with more severe frontal-striatal circuit dysfunction due to demyelination and neurodegeneration. Symmetrical standardized uptake values (SUVs) between hemispheres in all groups imply that fatigue in these conditions may be related to global or network-level alterations rather than hemisphere-specific changes. Future studies should employ fine-grained analysis methods, explore other brain regions, and control for confounding factors to better understand the pathophysiology of fatigue in MS and long COVID. Longitudinal studies tracking brain glucose metabolism in patients with Long COVID could provide insights into the evolution of metabolic patterns as the condition progresses. [ABSTRACT FROM AUTHOR]

Wilson's disease (WD) is a genetic disorder of copper metabolism that is inherited as an autosomal recessive (AR) due to mutations in the ATP7B gene, which is involved in intracellular copper transport. Approximately 40% to 50% of the patients present with neurological symptoms as their first symptom. The most common neurological symptoms are dysarthria, gait abnormalities, ataxia, dystonia, tremor, parkinsonism, and drooling. This case report aims to present a diagnostically challenging case of WD presenting with neurological symptoms. The 38-year-old male patient was admitted with complaints of imbalance, gait disturbance, weakness in the legs, speech impairment, tremors in the hands, syncope, and drooling. The MRI primarily revealed FLAIR, T1, and T hyperintensities in the bilateral globus pallidus of the basal ganglias. At first, the patient was evaluated according to the Leipzig scoring and received one point from the serum ceruloplasmin level and two points from the neurological symptoms and was evaluated as "possible WD" with a total of three points. 24-hour urine copper was collected during and after the D-Penicillamine challenge. After the test, there was an increase of more than 5 times the upper limit. The Leipzig score was recalculated, and a diagnosis of WD was made with a score of five. Even cases without important diagnostic findings such as Kayser-Fleischer ring or high 24-hour urine copper should be evaluated according to the Leipzig score. It is vital to distinguish WD in patients with young-onset movement disorder and neurological symptoms. [ABSTRACT FROM AUTHOR]

Electric arc furnace (EAF) slag is a coproduct of steel production used primarily for construction purposes. Some applications of EAF slag result in residential exposures by incidental ingestion and inhalation of airborne dust. To evaluate potential health risks, an EAF slag characterization program was conducted to measure concentrations of metals and leaching potential (including oral bioaccessibility) in 38 EAF slag samples. Arsenic, hexavalent chromium, iron, vanadium, and manganese (Mn) were identified as constituents of interest (COIs). Using a probabilistic risk assessment (PRA) approach, estimated distributions of dose for COIs were assessed, and increased cancer risks and noncancer hazard quotients (HQs) at the 50th and 95th percentiles were calculated. For the residents near slag‐covered roads, cancer risk and noncancer HQs were <1E − 6 and 1, respectively. For residential driveway or landscape exposure, at the 95th percentile, cancer risks were 1E − 6 and 7E − 07 based on oral exposure to arsenic and hexavalent chromium, respectively. HQs ranged from 0.07 to 2 with the upper bound due to ingestion of Mn among children. To expand the analysis, a previously published physiologically based pharmacokinetic (PBPK) model was used to estimate Mn levels in the globus pallidus for both exposure scenarios and further evaluate the potential for Mn neurotoxicity. The PBPK model estimated slightly increased Mn in the globus pallidus at the 95th percentile of exposure, but concentrations did not exceed no‐observed‐adverse‐effect levels for neurological effects. Overall, the assessment found that the application of EAF slag in residential areas is unlikely to pose a health hazard or increased cancer risk. [ABSTRACT FROM AUTHOR]

Basal ganglia (BG) circuits help guide and invigorate actions using predictions of future rewards (values). Within the BG, the globus pallidus pars externa (GPe) may play an essential role in aggregating and distributing value information. We recorded from the GPe in unrestrained rats performing both Pavlovian and instrumental tasks to obtain rewards and distinguished neuronal subtypes by their firing properties across the wake/sleep cycle and optogenetic tagging. In both tasks, the parvalbumin-positive (PV+), faster-firing prototypical neurons showed strong, sustained modulation by value, unlike other subtypes, including the arkypallidal cells that project back to striatum. Furthermore, we discovered that a distinct minority (7%) of GP cells display slower, pacemaker-like firing and encode reward prediction errors (RPEs) almost identically to midbrain dopamine neurons. These cell-specific forms of GPe value representation help define the circuit mechanisms by which the BG contribute to motivation and reinforcement learning.

Abstract Agyrophilic grains (AGs) are age-related limbic-predominant lesions in which four-repeat tau is selectively accumulated. Because previous methodologically heterogeneous studies have demonstrated inconsistent findings on the relationship between AGs and dementia, whether AGs affect cognitive function remains unclear. To address this question, we first comprehensively evaluated the distribution and quantity of Gallyas-positive AGs and the severity of neuronal loss in the limbic, neocortical, and subcortical regions in 30 cases of pure argyrophilic grain disease (pAGD) in Braak stages I–IV and without other degenerative diseases, and 34 control cases that had only neurofibrillary tangles with Braak stages I–IV and no or minimal Aβ deposits. Then, we examined whether AGs have independent effects on neuronal loss and dementia by employing multivariate ordered logistic regression and binomial logistic regression. Of 30 pAGD cases, three were classified in diffuse form pAGD, which had evident neuronal loss not only in the limbic region but also in the neocortex and subcortical nuclei. In all 30 pAGD cases, neuronal loss developed first in the amygdala, followed by temporo-frontal cortex, hippocampal CA1, substantia nigra, and finally, the striatum and globus pallidus with the progression of Saito AG stage. In multivariate analyses of 30 pAGD and 34 control cases, the Saito AG stage affected neuronal loss in the amygdala, hippocampal CA1, temporo-frontal cortex, striatum, globus pallidus, and substantia nigra independent of the age, Braak stage, and limbic-predominant age-related TDP-43 encephalopathy (LATE-NC) stage. In multivariate analyses of 23 pAGD and 28 control cases that lacked two or more lacunae and/or one or more large infarctions, 100 or more AGs per × 400 visual field in the amygdala (OR 10.02, 95% CI 1.12–89.43) and hippocampal CA1 (OR 12.22, 95% CI 1.70–87.81), and the presence of AGs in the inferior temporal cortex (OR 8.18, 95% CI 1.03–65.13) affected dementia independent of age, moderate Braak stages (III–IV), and LATE-NC. Given these findings, the high density of limbic AGs and the increase of AGs in the inferior temporal gyrus may contribute to the occurrence of dementia through neuronal loss, at least in cases in a low to moderate Braak stage.

Abstract Convenient and effective biomarkers are essential for the early diagnosis and treatment of Alzheimer’s disease (AD). In the cross-sectional study, 103 patients with AD, 82 patients with aMCI and 508 normal controls (NC) were enrolled. The single‐molecule array (Simoa) technique was used to assess the levels of plasma proteins, including NfL, T-tau, P-tau-181, Aβ40, Aβ42. Montreal Cognitive Assessment (MoCA) was used to assess the overall cognitive function of all subjects. Moreover, Amyloid PET and structural head MRI were also performed in a subset of the population. In the follow-up, the previous 508 normal older adults were followed up for two years, then COX regression analysis was used to investigate the association between baseline plasma proteins and future cognitive outcomes. NfL, T-tau, P-tau-181, Aβ40, Aβ42 and Aβ42/40 were altered in AD dementia, and NfL, Aβ42 and Aβ42/40 significantly outperformed all plasma proteins in differentiating AD dementia from NC, while NfL and Aβ42/40 could effectively distinguish between aMCI and NC. However, only plasma NfL was associated with future cognitive decline, and it was negatively correlated with MoCA (r = − 0.298, p

Viral vectors and lipofection‐based gene therapies have dispersion‐dependent transduction/transfection profiles that thwart precise targeting. The study describes the development of focused close‐field gene electrotransfer (GET) technology, refining spatial control of gene expression. Integration of fluidics for precise delivery of "naked" plasmid deoxyribonucleic acid (DNA) in sucrose carrier within the focused electric field enables negative biasing of near‐field conductivity ("conductivity‐clamping"–CC), increasing the efficiency of plasma membrane molecular translocation. This enables titratable gene delivery with unprecedently low charge transfer. The clinic‐ready bionics‐derived CC‐GET device achieved neurotrophin‐encoding miniplasmid DNA delivery to the cochlea to promote auditory nerve regeneration; validated in deafened guinea pig and cat models, leading to improved central auditory tuning with bionics‐based hearing. The performance of CC‐GET is evaluated in the brain, an organ problematic for pulsed electric field‐based plasmid DNA delivery, due to high required currents causing Joule‐heating and damaging electroporation. Here CC‐GET enables safe precision targeting of gene expression. In the guinea pig, reporter expression is enabled in physiologically critical brainstem regions, and in the striatum (globus pallidus region) delivery of a red‐shifted channelrhodopsin and a genetically‐encoded Ca2+ sensor, achieved photoactivated neuromodulation relevant to the treatment of Parkinson's Disease and other focal brain disorders. [ABSTRACT FROM AUTHOR]

Objectives: Deep-brain stimulation (DBS) has been used for the treatment of medically refractory dystonia with excellent results. In this study, we compared in detail the therapeutic advantages of two DBS targets for generalized isolated dystonia. Methods: In this retrospective study, we recruited 29 patients with generalized isolated dystonia who had undergone DBS treatment targeting either the globus pallidus interna (GPi) or the subthalamic nucleus (STN) in the Department of Functional Neurosurgery at Tiantan Hospital, Beijing, China, between January 2016 and December 2021. The movement and disability subscales of the Burke–Fahn–Marsden dystonia rating scale (BFMDRS) were used to assess the severity of their dystonic symptoms and their activities of daily living, respectively. SF-36 was used to evaluate the patients' health-related quality of life. Results: The percentage improvement in the BFMDRS-M score at 6 months relative to the baseline score was clearly higher in the STN group (63.91%) than in the GPi group (38.36%). At the 3-, 6-, and 12-month follow-ups, the percentage improvement in arm symptoms was significantly higher after DBS of the STN (70.64%, 80.66%, and 76.89%, respectively) than after stimulation of the GPi (36.75%, 34.21%, and 38.47%, respectively). At 12 months after surgery, patient quality of life had improved on all SF-36 subscales in both groups. Conclusions: STN-DBS may have more advantages than GPi-DBS in patients with obvious arm dystonia. STN-DBS had a better clinical effect than GPi-DBS within 6 months after surgery. [ABSTRACT FROM AUTHOR]

In patients with Parkinson's disease (PD), dopamine replacement therapy with dopamine D2/D3 receptor agonists induces impairments in decision-making, including pathological gambling. The neurobiological mechanisms underlying these adverse effects remain elusive. Here, in a mouse model of PD, we investigated the effects of the dopamine D3 receptor (D3R)-preferring agonist pramipexole (PPX) on decision-making. PD model mice were generated using a bilateral injection of the toxin 6-hydroxydopamine into the dorsolateral striatum. Subsequent treatment with PPX increased disadvantageous choices characterized by a high-risk/high-reward in the touchscreen-based Iowa Gambling Task. This effect was blocked by treatment with the selective D3R antagonist PG-01037. In model mice treated with PPX, the number of c-Fos-positive cells was increased in the external globus pallidus (GPe), indicating dysregulation of the indirect pathway in the corticothalamic-basal ganglia circuitry. In accordance, chemogenetic inhibition of the GPe restored normal c-Fos activation and rescued PPX-induced disadvantageous choices. These findings demonstrate that the hyperactivation of GPe neurons in the indirect pathway impairs decision-making in PD model mice. The results provide a candidate mechanism and therapeutic target for pathological gambling observed during D2/D3 receptor pharmacotherapy in PD patients. [ABSTRACT FROM AUTHOR]

Background Histologic and serologic studies suggest the induction of local and systemic Treponema pallidum -specific CD4+ T-cell responses to T. pallidum infection. We hypothesized that T. pallidum -specific CD4+ T cells are detectable in blood and in the skin rash of secondary syphilis and persist in both compartments after treatment. Methods Peripheral blood mononuclear cells collected from 67 participants were screened by interferon-γ (IFN-γ) ELISPOT response to T. pallidum sonicate. T. pallidum -reactive T-cell lines from blood and skin were probed for responses to 89 recombinant T. pallidum antigens. Peptide epitopes and HLA class II restriction were defined for selected antigens. Results We detected CD4+ T-cell responses to T. pallidum sonicate ex vivo. Using T. pallidum -reactive T-cell lines we observed recognition of 14 discrete proteins, 13 of which localize to bacterial membranes or the periplasmic space. After therapy, T. pallidum -specific T cells persisted for at least 6 months in skin and 10 years in blood. Conclusions T. pallidum infection elicits an antigen-specific CD4+ T-cell response in blood and skin. T. pallidum -specific CD4+ T cells persist as memory in both compartments long after curative therapy. The T. pallidum antigenic targets we identified may be high-priority vaccine candidates. [ABSTRACT FROM AUTHOR]

Background Objective Methods Results Conclusion Invasive deep brain stimulation (DBS) has been shown to be effective in treating patients with Parkinson's disease (PD), yet its clinical use is limited to patients at the advanced stage of the disease. Transcranial temporal interference stimulation (tTIS) may be a novel nonneurosurgical and safer alternative, yet its therapeutic potential remains unexplored.This pilot study aims to examine the feasibility and safety of tTIS targeting the right globus pallidus internus (GPi) for motor symptoms in patients with PD.Twelve participants with mild PD completed this randomized, double‐blind, and sham‐controlled experiment. Each of them received either 20‐minute or sham tTIS of the right GPi. Before and immediately after the stimulation, participants completed the Movement Disorder Society‐Unified Parkinson's Disease Rating Scale (MDS‐UPDRS‐III) in the “medication‐on” state to assess the motor symptoms. The blinding efficacy and side effects were also assessed.tTIS was well tolerated by participants, with only mild, transient adverse effects reported. tTIS significantly reduced MDS‐UPDRS‐III scores by 6.64 points (14.7%), particularly in bradykinesia (23.5%) and tremor (15.3%). The left side showed more significant alleviation in motor symptoms, particularly bradykinesia, compared to the right side. Participants with severer bradykinesia and tremor before stimulation experienced greater improvement after tTIS.This pilot study suggests that the tTIS, as a novel noninvasive DBS approach, is feasible and safe for alleviating motor symptoms in mild PD, especially bradykinesia and tremor. Future larger‐scale and more definitive studies are needed to confirm the benefits. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Humans and other animals readily transition from externally to internally focused attention, and these transitions are accompanied by activation of the default mode network (DMN). The DMN was considered a cortical network, yet recent evidence suggests subcortical structures are also involved. We investigated the role of ventral pallidum (VP) and mediodorsal thalamus (MD) in DMN regulation in tree shrew, a close relative of primates. Electrophysiology and deep learning-based classification of behavioral states revealed gamma oscillations in VP and MD coordinated with gamma in anterior cingulate (AC) cortex during DMN states. Cross-frequency coupling between gamma and delta oscillations was higher during DMN than other behaviors, underscoring the engagement of MD, VP and AC. Our findings highlight the importance of VP and MD in DMN regulation, extend homologies in DMN regulation among mammals, and underline the importance of thalamus and basal forebrain to the regulation of DMN. A study using electrophysiology, behavioral methods and modelling demonstrates the importance of the ventral pallidum and mediodorsal thalamus in DMN regulation in tree shrews. [ABSTRACT FROM AUTHOR]

Chorea-acanthocytosis (ChAc) is a rare, neurodegenerative disorder caused by mutations in the VPS13A gene. In this article, we report on a 32-year-old man diagnosed with ChAc, with involuntary movements of the mouth and trunk, drooling of the mouth, slurred speech, and abnormal vocalizations as the main clinical manifestations. Three weeks after implantation of globus pallidus internal (GPi)-deep brain stimulation (DBS), the patient's symptoms improved significantly. For example, articulation is clear, involuntary trunk movements and salivation have largely disappeared, and abnormal vocalizations have been significantly reduced. After 1 year of follow-up, the improvement in involuntary movement symptoms is essentially the same as before. As far as we know, we are the first to report the relief of involuntary vocalizations in a patient with GPi-DBS treatment, and that salivation and involuntary trunk movements have almost disappeared, and all other symptoms are significantly relieved, which is rare in previous cases. All of the above proves that the treatment of our case with DBS was very successful and that longer term follow-up is critical. We also hope that our case will provide new references and therapeutic ideas for the future treatment of patients with ChAc. [ABSTRACT FROM AUTHOR]

Although the initial symptoms of corticobasal degeneration (CBD) are varied, psychiatric symptoms are uncommon. Here, we report the autopsy findings of a patient with early CBD who presented with hallucinations. A 68‐year‐old man developed memory loss and visions of bears and insects. Because of slow vertical eye movement, postural instability, and levodopa‐unresponsive parkinsonism, the patient initially was clinically diagnosed with progressive supranuclear palsy. He died of a urinary tract infection 11 months after the onset of the disease. Histopathological examination revealed neuronal loss and gliosis, which were severe in the substantia nigra and moderate in the globus pallidus and subthalamic nucleus. Astrocytic plaques were scattered throughout the amygdala and premotor cortex. The superficial cortical layers lacked ballooned neurons and spongiosis, and tau deposition was greater in glia than in neurons. The amygdala contained a moderate number of argyrophilic grains and pretangles. Western blot analysis showed a 37‐kDa band among the low‐molecular‐weight tau fragments. Because the CBD pathology was mild, we attributed the patient's visual hallucinations to the marked argyrophilic grain pathology. CBD can occur with psychiatric symptoms, including visual hallucinations, and argyrophilic grain pathology may be associated with psychiatric symptoms. [ABSTRACT FROM AUTHOR]

Volitional modulation of neural activity is not confined to the cortex but extends to various brain regions. Yet, it remains unclear whether neurons in the basal ganglia structure, the external globus pallidus (GPe), can be volitionally controlled. Here, we employed a volitional conditioning task to compare the volitional modulation of GPe and primary motor cortex (M1) neurons as well as the underlying circuits and control mechanisms. The results revealed that the volitional modulation of GPe neuronal activity engaged both M1 and substantia nigra pars reticulata (SNr) neurons, indicating the involvement of the cortex–GPe–SNr loop. In contrast, the volitional modulation of M1 neurons primarily occurred through the engagement of M1 local circuitry. Furthermore, lesioning M1 neurons did not affect the volitional learning or volitional control signal in GPe, whereas lesioning of GPe neurons impaired the learning process for the volitional modulation of M1 neuronal activity at the intermediate stage. Additionally, lesion of GPe neurons enhanced M1 neuronal activity when performing the volitional control task without reward delivery and a random reward test. Taken together, our findings demonstrated that GPe neurons could be volitionally controlled by engagement of the cortical–basal ganglia circuit and inhibit learning process for the volitional modulation of M1 neuronal activity by regulating M1 neuronal activity. Thus, GPe neurons can be effectively harnessed for independent volitional modulation for neurorehabilitation in patients with cortical damage. Key points: The cortical–basal ganglia circuit contributes to the volitional modulation of GPe neurons.Volitional modulation of M1 neuronal activity mainly engages M1 local circuitry.Bilateral GPe lesioning impedes volitional learning at the intermediate stages.Lesioning of GPe neurons inhibits volitional learning process by regulating M1 neuronal activity. [ABSTRACT FROM AUTHOR]

Treponema pallidum is the causative factor of syphilis, a sexually transmitted disease (STD) characterized by perivascular infiltration of inflammatory cells, vascular leakage, swelling and proliferation of endothelial cells (ECs). The endothelium lining blood and lymphatic vessels is a key barrier separating body fluids from host tissues and is a major target of T. pallidum. In this review, we focus on how T. pallidum establish intimate interactions with ECs, triggering endothelial dysfunction such as endothelial inflammation, abnormal repairment and damage of ECs. In addition, we summarize that migration and invasion of T. pallidum across vascular ECs may occur through two pathways. These two mechanisms of transendothelial migration are paracellular and cholesterol‐dependent, respectively. Herein, clarifying the relationship between T. pallidum and endothelial dysfunction is of great significance to provide novel strategies for diagnosis and prevention of syphilis, and has a great potential prospect of clinical application. [ABSTRACT FROM AUTHOR]

Objective: Subcortical nuclei such as the thalamus and striatum have been shown to be related to seizure modulation and termination, especially in drug‐resistant epilepsy. Enhance diffusion‐weighted imaging (eDWI) technique and tri‐component model have been used in previous studies to calculate apparent diffusion coefficient from ultra high b‐values (ADCuh). This study aimed to explore the alterations of ADCuh in the bilateral thalamus and striatum in MRI‐negative drug‐resistant epilepsy. Methods: Twenty‐nine patients with MRI‐negative drug‐resistant epilepsy and 18 healthy controls underwent eDWI scan with 15 b‐values (0–5000 s/mm2). The eDWI parameters including standard ADC (ADCst), pure water diffusion (D), and ADCuh were calculated from the 15 b‐values. Regions‐of‐interest (ROIs) analyses were conducted in the bilateral thalamus, caudate nucleus, putamen, and globus pallidus. ADCst, D, and ADCuh values were compared between the MRI‐negative drug‐resistant epilepsy patients and controls using multivariate generalized linear models. Inter‐rater reliability was assessed using the intra‐class correlation coefficient (ICC) and Bland–Altman (BA) analysis. False discovery rate (FDR) method was applied for multiple comparisons correction. Results: ADCuh values in the bilateral thalamus, caudate nucleus, putamen, and globus pallidus in MRI‐negative drug‐resistant epilepsy were significantly higher than those in the healthy control subjects (all p < 0.05, FDR corrected). Significance: The alterations of the ADCuh values in the bilateral thalamus and striatum in MRI‐negative drug‐resistant epilepsy might reflect abnormal membrane water permeability in MRI‐negative drug‐resistant epilepsy. ADCuh might be a sensitive measurement for evaluating subcortical nuclei‐related brain damage in epilepsy patients. Plain Language Summary: This study aimed to explore the alterations of apparent diffusion coefficient calculated from ultra high b‐values (ADCuh) in the subcortical nuclei such as the bilateral thalamus and striatum in MRI‐negative drug‐resistant epilepsy. The bilateral thalamus and striatum showed higher ADCuh in epilepsy patients than healthy controls. These findings may add new evidences of subcortical nuclei abnormalities related to water and ion hemostasis in epilepsy patients, which might help to elucidate the underlying epileptic neuropathophysiological mechanisms and facilitate the exploration of therapeutic targets. [ABSTRACT FROM AUTHOR]