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Anorexia nervosa (AN) is associated with food restriction and significantly low body weight, but the neurobiology of food avoidance in AN is unknown. Animal research suggests that food avoidance can be triggered by conditioned fear that engages the anterior cingulate and nucleus accumbens. We hypothesized that the neural activation during food avoidance in AN could be modeled based on aversive goal value processing. Nineteen females with AN and thirty healthy controls matched for age underwent functional magnetic resonance brain imaging while conducting a food avoidance task. During active control free-bid and computer-generated forced-bid trials, participants bid money to avoid eating food items. Brain activation was parametrically modulated with the trial-by-trial placed bids. During free-bid trials, the AN group engaged the caudate nucleus, nucleus accumbens, ventral anterior cingulate, and inferior and medial orbitofrontal cortex more than the control group. High- versus low-bid trials in the AN group were associated with higher caudate nucleus response. Emotion dysregulation and intolerance of uncertainty scores were inversely associated with nucleus accumbens free-bid trial brain response in AN. This study supports the idea that food avoidance behavior in AN involves aversive goal value computation in the nucleus accumbens, caudate nucleus, anterior cingulate, and orbitofrontal cortex.

BACKGROUND: It is well-established that parental obesity is a strong risk factor for offspring obesity. Further, a converging body of evidence now suggests that maternal weight profiles may affect the developing offsprings brain in a manner that confers future obesity risk. Here, we investigated how pre-pregnancy maternal weight status influences the reward-related striatal areas of the offsprings brain during in utero development. METHODS: We used diffusion tensor imaging to quantify the microstructure of the striatal brain regions of interest in neonates (N = 116 [66 males, 50 females], mean gestational weeks at birth [39.88], SD = 1.14; at scan [43.56], SD = 1.05). Linear regression was used to test the associations between maternal pre-pregnancy body mass index (BMI) and infant striatal mean diffusivity. RESULTS: High maternal pre-pregnancy BMI was associated with higher mean MD values in the infants left caudate nucleus. Results remained unchanged after the adjustment for covariates. CONCLUSIONS: In utero exposure to maternal adiposity might have a growth-impairing impact on the mean diffusivity of the infants left caudate nucleus. Considering the involvement of the caudate nucleus in regulating eating behavior and food-related reward processing later in life, this finding calls for further investigations to define the prognostic relevance of early-life caudate nucleus development and weight trajectories of the offspring.

Background/Objectives: Huntington's disease (HD) is a fully penetrant neurodegenerative disease with a profound effect on quality of life. In recent years, there has been rapid growth in the description of its pathogenesis and diagnosis. Magnetic resonance spectroscopy (MRS) measurements can aid in the discrimination between premanifest Huntington's disease (Pre-HD) and healthy control (HC) subjects to establish early supportive and symptomatic management. Our objective was to evaluate metabolic changes using MRS to shed light on its potential as a biomarker through a systematic review. Methods: We followed the PRISMA guidelines, extracting articles from PubMed, Scopus, and the Virtual Health Library. We included patients with pre-HD, HD, and HC subjected to MRS, reporting the concentration of metabolites in at least one brain region. Results: In the putamen, N-acetyl Aspartate (NAA) was significantly decreased in 77.9% and total NAA (tNAA) was decreased in 72.4% of cases; no significant difference was found in 27.5% (n = 19) of cases. Furthermore, when looking into HD vs. pre-HD in the putamen, tNAA and NAA were decreased in 100% of participants. In the caudate nucleus, NAA and creatine were significantly decreased in 100% of HD in comparison to pre-HD participants, whereas tNAA showed a significant decrease in only 50%. Conclusions: MRS can be a relevant tool for the early diagnosis of HD; potential objective biomarkers related to its onset and pathogenesis exist and show differences between controls, pre-HD and HD patients. However, an effort should be made to standardize MRS methodology and reporting in subsequent studies. [ABSTRACT FROM AUTHOR]

Schizophrenia is a severe psychiatric disorder associated with brain alterations at rest. Amplitude of low-frequency fluctuations (ALFF) and its fractional version (fALFF) have been widely used to investigate alterations in spontaneous brain activity in schizophrenia. However, results are still inconsistent. Furthermore, while these measurements are similar, they showed some differences, and no meta-analysis has been yet performed to compare them in schizophrenia. Thus, we conducted systematic research in five databases and in the grey literature to find articles investigating fALFF and/or ALFF alterations in schizophrenia. Two separate meta-analyses were performed using the SDM-PSI software to identify fALFF and ALFF alterations separately. Then, a conjunction analysis was conducted to determine congruent results between the two approaches. We found that patients with schizophrenia showed altered fALFF activity in the left insula/putamen, the right paracentral lobule and the left middle occipital gyrus compared to healthy individuals. Patients with schizophrenia exhibited ALFF alterations in the bilateral putamen, the bilateral caudate nucleus, the bilateral inferior frontal gyrus, the right precuneus, the right precentral gyrus, the left postcentral gyrus, the right posterior cingulate gyrus, compared to healthy controls. ALFF increased activity in the left putamen was higher in drug-naïve patients and was correlated with positive symptoms. The conjunction analysis revealed a spatial convergence between fALFF and ALFF studies in the left putamen. This left putamen cluster is part of the associative striatum. Its alteration in schizophrenia provides additional support to the influential aberrant salience hypothesis of psychosis. [ABSTRACT FROM AUTHOR]

• Smaller volumes in amygdalae and caudate nuclei were observed in neonates with exposed to ACS. • Volumetric changes were observed only in neonates born at ≥28 gestational weeks. • ACS led to local neuroanatomical changes that are not detectable by conventional MRI. Antenatal corticosteroids (ACS) is a well-established treatment for women at risk of preterm birth that improves neonatal outcomes. However, several concerns have been raised regarding the potential long-term adverse effects of ACS on the offspring's developing brain. Here we investigated the association between ACS and subcortical segmental volumes in preterm infants at term-equivalent age. This retrospective observational study was conducted using the clinical data of preterm singleton infants born between 220/7 and 336/7 gestational weeks at Nagoya University Hospital in 2014–2020. Subcortical volumes of the bilateral thalami, caudate nuclei, putamens, pallidums, hippocampi, amygdalae, and nuclei accumbens were evaluated using an automated segmentation tool, Infant FreeSurfer, and compared between neonates exposed to a single course of ACS (n = 46) and those who were not (n = 13) by multiple linear regression analysis (covariates: postmenstrual age at magnetic resonance imaging, infant sex, and gestational age at birth). We compared each subcortical volume stratified by gestational age at birth (<28 vs. ≥28 gestational weeks). Multivariate analyses revealed significantly smaller volumes in the bilateral amygdalae (left, p < 0.03; right, p < 0.03) and caudate nuclei (left, p < 0.03; right, p = 0.04) in neonates with ACS. Significantly smaller volumes in these regions were observed only in neonates born at 28 weeks of gestation or later. ACS was associated with smaller volumes of the bilateral amygdalae and caudate nuclei at term-equivalent age. This association was observed exclusively in infants born at 28 weeks of gestation or later. [ABSTRACT FROM AUTHOR]

• Age-related SFC changes in specific brain regions are related to cognitive decline. • Elevated SFC of thalamus partially mediates age-related cognitive decline. • Elevated SFC of PFC partially mediates decline in executive function. Normal aging is accompanied by changes in brain structure and function associated with cognitive decline. Structural and functional abnormalities, particularly the prefrontal cortex (PFC) and subcortical regions, contributed to cognitive aging. However, it remains unclear how the synchronized changes in structure and function of individual brain regions affect the cognition in aging. Using 3D T1-weighted structural data and movie watching functional magnetic resonance imaging data in a sample of 422 healthy individuals (ages from 18 to 87 years), we constructed regional structure–function coupling (SFC) of cortical and subcortical regions by quantifying the distribution similarity of gray matter volume (GMV) and amplitude of low-frequency fluctuation (ALFF). Further, we investigated age-related changes in SFC and its relationship with cognition. With aging, increased SFC localized in PFC, thalamus and caudate nucleus, decreased SFC in temporal cortex, lateral occipital cortex and putamen. Moreover, the SFC in the PFC was associated with executive function and thalamus was associated with the fluid intelligence, and partially mediated age-related cognitive decline. Collectively, our results highlight that tighter structure–function synchron of the PFC and thalamus might contribute to age-related cognitive decline, and provide insight into the substrate of the thalamo-prefrontal pathway with cognitive aging. [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]

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease with a fatal outcome. There is accumulating evidence of a prominent role of glia in the pathology of HD, and we investigated this by conducting single nuclear RNA sequencing (snRNAseq) of human post mortem brain in four differentially affected regions; caudate nucleus, frontal cortex, hippocampus and cerebellum. Across 127,205 nuclei from donors with HD and age/sex matched controls, we found heterogeneity of glia which is altered in HD. We describe prominent changes in the abundance of certain subtypes of astrocytes, microglia, oligodendrocyte precursor cells and oligodendrocytes between HD and control samples, and these differences are widespread across brain regions. Furthermore, we highlight possible mechanisms that characterise the glial contribution to HD pathology including depletion of myelinating oligodendrocytes, an oligodendrocyte-specific upregulation of the calmodulin-dependent 3',5'-cyclic nucleotide phosphodiesterase 1 A (PDE1A) and an upregulation of molecular chaperones as a cross-glial signature and a potential adaptive response to the accumulation of mutant huntingtin (mHTT). Our results support the hypothesis that glia have an important role in the pathology of HD, and show that all types of glia are affected in the disease. [ABSTRACT FROM AUTHOR]

Objective Methods Results Interpretation Granger causal analysis (GCA) and amplitude of low‐frequency fluctuation (ALFF) are commonly used to evaluate functional alterations in brain disorders. By combining the GCA and ALFF, this study aimed to investigate the effective connectivity (EC) changes in patients with acute ischemic stroke (AIS) and anterior circulation occlusion after mechanical thrombectomy (MT).Resting‐state functional magnetic resonance imaging (rs‐fMRI) data were collected from 43 AIS patients with anterior circulation occlusion within 1 week post‐MT and 37 healthy controls. ALFF and GCA were calculated for each participant. Patients were further divided into groups based on prognosis and perfusion levels. The differences in ALFF and EC were compared between AIS patients and healthy controls and between subgroups of patients. Pearson correlations between EC, ALFF values, and clinical characteristics of patients were calculated.Compared to healthy controls, post‐MT, AIS patients exhibited significant ALFF increases in the left precuneus and decreases in the left fusiform gyrus and right caudate. Increased EC from the contralesional lingual gyrus, contralesional putamen, ipsilesional thalamus, and contralesional thalamus to the contralesional caudate was obsrved, while decrease in EC were found for contralesional caudate to the ipsilesional thalamus and medial superior frontal gyrus. EC differences were particularly notable between perfusion groups, with significantly lower EC in the poorly perfused group. EC values were also positively correlated with National Institutes of Health Stroke Scale (NIHSS) scores pre‐MT.In AIS patients, the caudate nucleus was central to the observed EC changes post‐MT, characterized by decreased outputs and increased inputs. These changes indicate functional remodeling within the cortico‐basal ganglia‐thalamic‐cortical pathway. [ABSTRACT FROM AUTHOR]

Objective: Chronic kidney disease (CKD) is increasingly recognized as a risk factor for alterations in brain function. However, detecting early‐stage symptoms and structural changes remains challenging, potentially leading to delayed treatment. In our study, we aimed to investigate spontaneous brain activity changes in CKD patients using resting‐state functional magnetic resonance imaging (fMRI). Additionally, we explored the correlation between common biomarkers reflecting CKD severity and brain activity. Methods: We recruited a cohort of 22 non–dialysis‐dependent CKD patients and 22 controls for resting‐state fMRI scans. Amplitude of low‐frequency fluctuations (ALFFs) and regional homogeneity (ReHo) were calculated to evaluate brain activity. Regression analysis was conducted to explore the correlations between biomarkers reflecting the severity of CKD and brain activity. Results: CKD patients exhibited reduced z‐scored ALFF (zALFF) and mean ALFF (mALFF) in the bilateral putamen, right caudate nucleus, left anterior cingulate, and right precuneus. Changes in bilateral putamen were also found in smCohe‐ReHo and szCohe‐ReHo analyses. Urine albumin‐to‐creatinine ratio (UACR), urine protein‐to‐creatinine ratio (UPCR), and serum albumin levels were associated with attenuated putamen activity. Conclusion: Non–dialysis‐dependent CKD patients had changes in zALFF, mALFF, smCohe‐ReHo, and szCohe‐ReHo values in specific brain regions, especially bilateral putamen. UACR, UPCR, and serum albumin levels are associated with putamen activity attenuation in rs‐fMRI. [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]

Background and objectives: The premanifest phase of Huntington's disease (HD) is characterized by the absence of motor symptoms and exhibits structural changes in imaging that precede clinical manifestation. This study aimed to analyze volumetric changes identified through brain magnetic resonance imaging (MRI) processed using artificial intelligence (AI) software in premanifest HD individuals, focusing on the relationship between CAG triplet expansion and structural biomarkers. Methods: The study included 36 individuals descending from families affected by HD in the Department of Atlántico. Sociodemographic data were collected, followed by peripheral blood sampling to extract genomic DNA for quantifying CAG trinucleotide repeats in the Huntingtin gene. Brain volumes were evaluated using AI software (Entelai/IMEXHS, v4.3.4) based on MRI volumetric images. Correlations between brain volumes and variables such as age, sex, and disease status were determined. All analyses were conducted using SPSS (v. IBM SPSS Statistics 26), with significance set at p < 0.05. Results: The analysis of brain volumes according to CAG repeat expansion shows that individuals with ≥40 repeats evidence significant increases in cerebrospinal fluid (CSF) volume and subcortical structures such as the amygdalae and left caudate nucleus, along with marked reductions in cerebral white matter, the cerebellum, brainstem, and left pallidum. In contrast, those with <40 repeats show minimal or moderate volumetric changes, primarily in white matter and CSF. Conclusions: These findings suggest that CAG expansion selectively impacts key brain regions, potentially influencing the progression of Huntington's disease, and that AI in neuroimaging could identify structural biomarkers long before clinical symptoms appear. [ABSTRACT FROM AUTHOR]

Purpose: GM1-gangliosidosis (GM1) leads to extensive neurodegenerative changes and atrophy that precludes the use of automated MRI segmentation techniques for generating brain volumetrics. We developed a standardized segmentation protocol for brain MRIs of patients with type II GM1 and then assessed the inter- and intra-rater reliability of thismethodology. The volumetric data may be used as a biomarker of disease burden and progression, and standardized methodology may support research into the natural history of the disease which is currently lacking in the literature. Approach: Twenty-five brain MRIs were included in this study from 22 type II GM1 patients of which 8 were late-infantile subtype and 14 were juvenile subtype. The following structures were segmented by two rating teams on a slice-by-slice basis: whole brain, ventricles, cerebellum, lentiform nucleus, thalamus, corpus callosum, and caudate nucleus. The inter- and intra-rater reliability of the segmentationmethod was assessed with an intraclass correlation coeffcient as well as Sorensen-Dice and Jaccard coeffcients. Results: Based on the Sorensen-Dice and Jaccard coeffcients, the inter- and intra-rater reliability of the segmentation method was significantly better for the juvenile patients compared to late-infantile (p < 0.01). In addition, the agreement between the two rater teams and within themselves can be considered good with all p-values < 0.05. Conclusions: The standardized segmentation approach described here has good inter- and intra-rater reliability and may provide greater accuracy and reproducibility for neuromorphological studies in this group of patients and help to further expand our understanding of the natural history of this disease. [ABSTRACT FROM AUTHOR]

Objective: Explore the plasticity of the frontal associative areas in children and adolescents induced by exercise and potential moderating variables. Methods: Computer searches of CNKI, WOS, PubMed and EBSCO databases were conducted, and statistical analyses were performed based on SPSS 25.0, Stata 12.0 and Ginger ALE 2.3 software after literature screening, data extraction and quality assessment were performed independently by two researchers. Results: A total of 13 articles, including 425 participants aged 8.9-16.8 years, were included. Frequency analysis revealed that exercise induced enhanced activation in frontal, parietal, occipital, limbic system and cerebellum (P < 0.01). Activation Likelihood Estimation (ALE) meta-analysis revealed that exercise altered the activation status of the frontal association (medial frontal gyrus, middle frontal gyrus, inferior frontal gyrus and precentral gyrus), cuneus, lingual gyrus, cingulate gyrus, parahippocampal gyrus, caudate nucleus and cerebellar apex, with the volume of activation in the frontal association accounting for 61.81% of the total activation cluster volume and an enhanced activation effect. Additionally, the study design, age, gender, nationality, cognitive tasks, as well as exercise intensity, intervention time, and type of exercise may be potential moderating variables. Particularly, sustained exercise induced a decrease in activation in the left parahippocampal gyrus, culmen, and lingual gyrus, while variable exercise induced an increase in activation in the left middle frontal gyrus. Conclusion: Exercise-induced activation increase in the frontal associative areas of children and adolescents is dominant, especially longer periods of moderateintensity variable exercise can induce more brain region activation. However, some of the included studies are cross-sectional, and the accuracy of the results still requires further verification. [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]

Anhedonia is a transdiagnostic symptom often resistant to treatment. The identification of biomarkers sensitive to anhedonia treatment will aid in the evaluation of novel anhedonia interventions. This is an exploratory analysis of changes in subcortical brain volumes accompanying psychotherapy in a transdiagnostic anhedonic sample using ultra-high field (7-Tesla) MRI. Outpatients with clinically impairing anhedonia (n = 116) received Behavioral Activation Treatment for Anhedonia, a novel psychotherapy, or Mindfulness-Based Cognitive Therapy (ClinicalTrials.gov Identifiers NCT02874534 and NCT04036136). Subcortical brain volumes were estimated via the MultisegPipeline, and regions of interest were the amygdala, caudate nucleus, hippocampus, pallidum, putamen, and thalamus. Bivariate mixed effects models estimated pre-treatment relations between anhedonia severity and subcortical brain volumes, change over time in subcortical brain volumes, and associations between changes in subcortical brain volumes and changes in anhedonia symptoms. As reported previously (Cernasov et al., 2023), both forms of psychotherapy resulted in equivalent and significant reductions in anhedonia symptoms. Pre-treatment anhedonia severity and subcortical brain volumes were not related. No changes in subcortical brain volumes were observed over the course of treatment. Additionally, no relations were observed between changes in subcortical brain volumes and changes in anhedonia severity over the course of treatment. This trial included a modest sample size and did not have a waitlist-control condition or a non-anhedonic comparison group. In this exploratory analysis, psychotherapy for anhedonia was not accompanied by changes in subcortical brain volumes, suggesting that subcortical brain volumes may not be a candidate biomarker sensitive to response to psychotherapy. • Pre-treatment anhedonia severity and pre-treatment subcortical brain volumes were not related. • Psychotherapy for anhedonia was not accompanied by changes in subcortical brain volumes. • There was a modest relation between pre-treatment anhedonia and change in caudate nucleus volumes during treatment. • Subcortical brain volumes may not be a candidate biomarker sensitive to response to psychotherapy. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to assess COVID‐19‐related gray matter (GM) structural alterations in two distinct groups of patients presenting with the prevailing and distinctive COVID‐19‐related neurological symptoms – isolated olfactory disorders as sole neurological manifestation (COVID‐OD) and cognitive disorders (COVID‐CD) – as compared to a control group of unaffected individuals. Methods: The study included 61 COVID‐CD patients (57 [60–63] years, 62% females), 84 COVID‐OD patients (49 [35–57] years, 60% females), and 17 controls (51 [41–52] years, 41% females). Region‐based morphometry (RBM) and voxel‐based morphometry (VBM) were performed on T1‐weighted MRI scans to assess GM regional volume and voxel‐wise density differences between COVID‐19 patients and controls. Surface‐based morphometry (SBM) was applied to investigate cortical thickness alterations. The statistical models built to assess GM structural differences among groups included total intracranial volume and age as nuisance variables. Results: The multi‐morphometric analysis revealed statistically significant (p < 0.05 corrected for multiple comparisons) reduction in GM regional volumes, in voxel‐wise GM density and in cortical thickness in both COVID‐CD and COVID‐OD patient groups as compared to controls. Across all three analyses, COVID‐CD patients showed more distributed and severe GM loss than COVID‐OD patients. The most prominently affected GM regions in the COVID‐CD group included the hippocampus, putamen, cingulate gyrus, precuneus, precentral and postcentral gyri, amygdala, lingual gyrus, and caudate nucleus. Interpretation: Our MRI findings show that COVID‐19‐related olfactory and cognitive disorders both induce GM atrophy, although at different degrees of severity, likely indicative of neurodegeneration and neuroinflammation. [ABSTRACT FROM AUTHOR]

The dorsal striatum is composed of the caudate nucleus and the putamen in human and non‐human primates. These two regions receive different cortical projections and are functionally distinct. The caudate is involved in the control of goal‐directed behaviors, while the putamen is implicated in habit learning and formation. Previous reports indicate that ethanol differentially influences neurotransmission in these two regions. Because neurotransmitters primarily signal through G protein‐coupled receptors (GPCRs) to modulate neuronal activity, the present study aimed to determine whether ethanol had a region‐dependent impact on the expression of proteins that are involved in the trafficking and function of GPCRs, including G protein subunits and their effectors, protein kinases, and elements of the cytoskeleton. Western blotting was performed to examine protein levels in the caudate and the putamen of male cynomolgus macaques that self‐administered ethanol for 1 year under free access conditions, along with control animals that self‐administered an isocaloric sweetened solution under identical operant conditions. Among the 18 proteins studied, we found that the levels of one protein (PKCβ) were increased, and 13 proteins (Gαi1/3, Gαi2, Gαo, Gβ1γ, PKCα, PKCε, CaMKII, GSK3β, β‐actin, cofilin, α‐tubulin, and tubulin polymerization promoting protein) were reduced in the caudate of alcohol‐drinking macaques. However, ethanol did not alter the expression of any proteins examined in the putamen. These observations underscore the unique vulnerability of the caudate nucleus to changes in protein expression induced by chronic ethanol exposure. Whether these alterations are associated with ethanol‐induced dysregulation of GPCR function and neurotransmission warrants future investigation. [ABSTRACT FROM AUTHOR]

Multifractal analysis offers a sophisticated method to examine the complex morphology of neurons, which traditionally have been analyzed using monofractal techniques. This study investigates the multifractal properties of two-dimensional neuron projections from the human dorsal striatum, focusing on potential morphological changes related to aging and differences based on spatial origin within the nucleus. Using multifractal spectra, we analyzed various parameters, including generalized dimensions and Hölder exponents, to characterize the neurons' morphology. Despite the detailed analysis, no significant correlation was found between neuronal morphology and age. However, clear morphological differences were observed between neurons from the caudate nucleus and the putamen. Neurons from the putamen displayed higher morphological complexity and greater local homogeneity, while those from the caudate nucleus exhibited more scaling laws and higher local heterogeneity. These findings suggest that while age may not significantly impact neuronal morphology in the dorsal striatum, the spatial origin within this brain region plays a crucial role in determining neuronal structure. Further studies with larger samples are recommended to confirm these findings and to explore the full potential of multifractal analysis in neuronal morphology research. [ABSTRACT FROM AUTHOR]

Introduction: FTLD-FET is a newly described subtype of frontotemporal lobar degeneration (FTLD characterized by pathologic inclusions of FET proteins: fused in sarcoma (FUS), Ewing sarcoma, and TATA-binding protein-associated factor 2N (TAF15)). Severe caudate volume loss on MRI has been linked to FTLD-FUS, yet glucose hypometabolism in FTLD-FET has not been studied. We assessed [18F] fluorodeoxyglucose PET (FDG-PET) hypometabolism in FTLD-FET subtypes and compared metabolism to FTLD-tau and FTLD-TDP. Methods: We retrospectively reviewed medical records of 26 autopsied FTLD patients (six FTLD-FET, ten FTLD-Tau, and ten FTLD-TDP) who had completed antemortem FDG-PET. We evaluated five regions, caudate nucleus, medial frontal cortex, lateral frontal cortex, and medial temporal using a 0–3 visual rating scale and validated our findings quantitatively using CORTEX-ID suite Z scores. Results: Of the six FTLD-FET cases (three females) with median age at onset = 36, three were atypical FTLD-U (aFTLD-U) and three were neuronal intermediate filament inclusion disease (NIFID). bvFTD was the most common presentation. Four of the six FTLD cases (3 aFTLD-U + 1 NIFID) showed prominent caudate hypometabolism relatively early in the disease course. FTLD-tau and FTLD-TDP did not show early prominent caudate hypometabolism. Hypometabolism in medial and lateral temporal cortex was associated with FTLD-TDP, while FTLD-tau had normal-minimal regional metabolism. Discussion: Prominent caudate hypometabolism, especially early in the disease course, appears to be a hallmark feature of the aFTLD-U subtype of FTLD-FET. Assessing caudate and temporal hypometabolism on FDG-PET will help to differentiate FTLD-FET from FTLD-tau and FTLD-TDP. [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]

Cognitive dysfunction constitutes a core characteristic of schizophrenia spectrum disorders (SZ). Specifically, deficits in updating generative models (i.e., cognitive flexibility) and shielding against distractions (i.e., cognitive stability) are considered critical contributors to cognitive impairment in these patients. Here, we examined the structural integrity of frontostriatal networks and their associations with reduced cognitive stability and flexibility in SZ patients. In a sample of 21 patients diagnosed with SZ and 22 healthy controls, we measured gray matter volume (GMV) using structural MRI. Further, cognitive stability and flexibility were assessed using a switch‐drift paradigm, quantifying the successful ignoring of distracters and detection of rule switches. Compared to controls, patients showed significantly smaller GMV in the whole brain and three predefined regions of interest: the medial prefrontal cortex (mPFC), inferior frontal gyrus (IFG), and caudate nucleus (CN). Notably, GMV in these areas positively correlated with correct rule‐switch detection but not with ignoring rule‐compatible drifts. Further, the volumetric differences between SZ patients and controls were statistically explainable by considering the behavioral performance in the switch‐drift task. Our results indicate that morphological abnormalities in frontostriatal networks are associated with deficient flexibility in SZ patients and highlight the necessity of minimizing neurodevelopmental and progressive brain atrophy in this population. Cognitive dysfunction constitutes a core characteristic of schizophrenia spectrum disorders (SZ). The current study indicates that morphological abnormalities in frontostriatal networks are associated with deficient cognitive flexibility in SZ patients and highlight the necessity of minimizing neurodevelopmental and progressive brain atrophy in this population. [ABSTRACT FROM AUTHOR]

Temporal discounting, in which the recipient of a reward perceives the value of that reward to decrease with delay in its receipt, is associated with impulsivity and psychiatric disorders such as depression. Here, we investigate the role of the serotonin 5-HT4 receptor (5-HT4R) in modulating temporal discounting in the macaque dorsal caudate nucleus (dCDh), the neurons of which have been shown to represent temporally discounted value. We first mapped the 5-HT4R distribution in macaque brains using positron emission tomography (PET) imaging and confirmed dense expression of 5-HT4R in the dCDh. We then examined the effects of a specific 5-HT4R antagonist infused into the dCDh. Blockade of 5-HT4R significantly increased error rates in a goal-directed delayed reward task, indicating an increase in the rate of temporal discounting. This increase was specific to the 5-HT4R blockade because saline controls showed no such effect. The results demonstrate that 5-HT4Rs in the dCDh are involved in reward-evaluation processes, particularly in the context of delay discounting, and suggest that serotonergic transmission via 5-HT4R may be a key component in the neural mechanisms underlying impulsive decisions, potentially contributing to depressive symptoms. [ABSTRACT FROM AUTHOR]

Introduction: Sleep disorders are prevalent and significant among individuals receiving methadone maintenance treatment (MMT), adversely affecting their quality of life and treatment adherence. While cerebral blood flow (CBF) plays a crucial role in the development of various diseases, its relationship with sleep disorders remains uncertain. This observational study focuses on possible correlations between CBF and poor subjective sleep quality in MMT patients. Methods: A total of 75 participants with a history of MMT were recruited and assessed using pseudo-continuous arterial spin labeling magnetic resonance imaging to determine CBF. A LAASO regression model was employed to identify the region of interest (ROI) most associated with sleep disturbance. The association between the CBF of the ROI and the Pittsburgh Sleep Quality Index (PSQI) was examined using regression analyses. Age, gender, BMI, history of hypertension, diabetes, hyperlipidemia, and methadone withdrawal were included as covariates. Results: Among MMT patients with poor subjective sleep quality, significantly higher CBF was observed in the right paracentral lobule (56.1057 ± 11.1624 ml/100 g/min, p=0.044), right cerebelum&lowbar;3 (56.6723±15.3139ml/100 g/min, p = 0.026), right caudate nucleus (48.9168 ± 6.9910ml/100 g/min, p = 0.009), and left caudate nucleus (47.6207 ± 6.1374 ml/100 g/min, p = 0.006). Furthermore, a positive correlation was found between CBF in the right paracentral lobule and the total PSQI score (β = 0.1135, p = 0.0323), with the association remaining significant even after adjustment for covariates (β = 0.1276, p = 0.0405). Conclusion: MMT patients with poor subjective sleep quality exhibited significantly altered CBF in multiple brain regions. The association between increased CBF in the right paracentral lobule and subjective sleep quality in MMT patients could be crucial in understanding sleep disorders in individuals undergoing MMT. Clinical trial registration: https://www.chictr.org.cn/, identifier: ChiCTR 2100051931. [ABSTRACT FROM AUTHOR]

Spontaneous reversion from mild cognitive impairment (MCI) to normal cognition (NC) is little known. Based on the data of the Genetics of Personality Consortium and MCI participants from Alzheimer's Disease Neuroimaging Initiative, the authors investigate the effect of polygenic scores (PGS) for personality traits on the reversion of MCI to NC and its underlying neurobiology. PGS analysis reveals that PGS for conscientiousness (PGS‐C) is a protective factor that supports the reversion from MCI to NC. Gene ontology enrichment analysis and tissue‐specific enrichment analysis indicate that the protective effect of PGS‐C may be attributed to affecting the glutamatergic synapses of subcortical structures, such as hippocampus, amygdala, nucleus accumbens, and caudate nucleus. The structural covariance network (SCN) analysis suggests that the left whole hippocampus and its subfields, and the left whole amygdala and its subnuclei show significantly stronger covariance with several high‐cognition relevant brain regions in the MCI reverters compared to the stable MCI participants, which may help illustrate the underlying neural mechanism of the protective effect of PGS‐C. [ABSTRACT FROM AUTHOR]

A 55‐year‐old Japanese woman with a history of hypertension and right putaminal hemorrhage developed simultaneous hemorrhages in the left thalamus and putamen and died 24 h later. There were no vascular anomalies in the brain. Synaptophysin immunostaining combined with eosin azure 50 (EA50) staining clearly identified the hematoma and the surrounding brain structures. In the right cerebral hemisphere, a cystic lesion as a sequela of the usual type of hypertensive putaminal hematoma was evident. In the left cerebral hemisphere, two fresh hematomas were evident. One was a thalamic hematoma, which had destroyed the dorsal and medial structures of the thalamus, and the other was an unusual putaminal hematoma, which had destroyed the entire putamen and crossed the internal capsule and caudate nucleus. α‐Smooth muscle actin immunostaining combined with EA50 and Victoria bleu staining demonstrated three ruptured arteries associated with fibrin aggregates in the anterior thalamic nucleus and anterior putamen. Some circular structures composed of fibrin, suggesting the presence of ruptured arteries in the neighborhood, were evident in the thalamus and putamen. In the putamen, ruptured arteries and circular structures were present in the lateral to medial areas. Fibrin aggregates in the anterior thalamic nucleus were more numerous than those in the putamen. On the basis of these findings, we concluded that: (i) the artery with numerous fibrin aggregates in the anterior thalamic nucleus had ruptured first, followed by the arteries distributed in other parts of the thalamus and putamen; (ii) the unusual putaminal hematoma was attributable to rupture of the arteries around the center of the putamen, which are not responsible for the usual type of hypertensive putaminal hematoma; and (iii) it is suggested that even if hypertensive hemorrhage occurs simultaneously in the ipsilateral putamen and thalamus, the usual type of hypertensive mixed‐type hematoma does not form. [ABSTRACT FROM AUTHOR]

Functional neuroimaging studies demonstrate disinhibition of the cortico-striatal-thalamo-cortical circuit. However, structural imaging studies revealed conflicting results, some suggesting smaller volumes of the caudate nucleus (CN) in children with Gilles de la Tourette syndrome (TS). Here we wanted to find out whether transcranial sonography (TCS) detects alterations of raphe nuclei, substantia nigra, lenticular nucleus (LN), or CN in children with Tic disorder or TS (TIC/TS).The study included 25 treatment-naive children (age: 12.2 ± 2.5 years) with a DSM-V based diagnosis of Tic disorder or TS (10 subjects), without other psychiatric or neurologic diagnosis, and 25 healthy controls (age: 12.17 ± 2.57 years), matched for age and sex. Parental rating of behavioral, emotional abnormalities, somatic complaints and social competencies of the participants were assessed using the Child Behavior Check List (CBCL/4-18R). TCS of deep brain structures was conducted through the preauricular acoustic bone windows using a 2.5-MHz phased-array ultrasound system. Fisher's exact test and Mann-Whitney-U test were used for comparisons between TIC/TS patients and healthy volunteers. The number of participants with hyperechogenic area of left CN in the TIC/TS sample was increased, compared to the healthy control group. TIC/TS patients with hyperechogenic CN showed an increased occurrence of thought- and obsessive-compulsive problems. This TCS study revealed pathologic structural changes in CN, its higher occurrence in TIC/TS compared to healthy controls and the relation to comorbidity of thought problems. Further research should focus on the molecular cause of these alterations, probably the disturbed iron metabolism. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) manifests as a wide variety of clinical phenotypes and its progression varies greatly. However, the factors associated with different disease progression remain largely unknown. Methods: In this retrospective cohort study, we enrolled 113 patients who underwent 18F-FP-CIT PET scan twice. Given the negative exponential progression pattern of dopamine loss in PD, we applied the natural logarithm to the specific binding ratio (SBR) of two consecutive 18F-FP-CIT PET scans and conducted linear mixed model to calculate individual slope to define the progression rate of nigrostriatal degeneration. We investigated the clinical and dopamine transporter (DAT) availability patterns associated with the progression rate of dopamine depletion in each striatal sub-region. Results: More symmetric parkinsonism, the presence of dyslipidemia, lower K-MMSE total score, and lower anteroposterior gradient of the mean putaminal SBR were associated with faster progression rate of dopamine depletion in the caudate nucleus. More symmetric parkinsonism and lower anteroposterior gradient of the mean putaminal SBR were associated with faster depletion of dopamine in the anterior putamen. Older age at onset, more symmetric parkinsonism, the presence of dyslipidemia, and lower anteroposterior gradient of the mean putaminal SBR were associated with faster progression rate of dopamine depletion in the posterior putamen. Lower striatal mean SBR predicted the development of LID, while lower mean SBR in the caudate nuclei predicted the development of dementia. Discussion: Our results suggest that the evaluation of baseline clinical features and patterns of DAT availability can predict the progression of PD and its prognosis. [ABSTRACT FROM AUTHOR]

Objective: Persisting neurological symptoms after COVID‐19 affect up to 10% of patients and can manifest in fatigue and cognitive complaints. Based on recent evidence, we evaluated whether cerebral hemodynamic changes contribute to post‐COVID syndrome (PCS). Methods: Using resting‐state functional magnetic resonance imaging, we investigated brain perfusion and oxygen level estimates in 47 patients (44.4 ± 11.6 years; F:M = 38:9) and 47 individually matched healthy control participants. Group differences were calculated using two‐sample t‐tests. Multivariable linear regression was used for associations of each regional perfusion and oxygen level measure with cognition and sleepiness measures. Exploratory hazard ratios were calculated for each brain metric with clinical measures. Results: Patients presented with high levels of fatigue (79%) and daytime sleepiness (45%). We found widespread decreased brain oxygen levels, most evident in the white matter (false discovery rate adjusted‐p‐value (p‐FDR) = 0.038) and cortical grey matter (p‐FDR = 0.015). Brain perfusion did not differ between patients and healthy participants. However, delayed patient caudate nucleus perfusion was associated with better executive function (p‐FDR = 0.008). Delayed perfusion in the cortical grey matter and hippocampus were associated with a reduced risk of daytime sleepiness (hazard ratio (HR) = 0.07, p = 0.037 and HR = 0.06, p = 0.034). Decreased putamen oxygen levels were associated with a reduced risk of poor cognitive outcome (HR = 0.22, p = 0.019). Meanwhile, lower thalamic oxygen levels were associated with a higher risk of cognitive fatigue (HR = 6.29, p = 0.017). Interpretation: Our findings of lower regional brain blood oxygen levels suggest increased cerebral metabolism in PCS, which potentially holds a compensatory function. These hemodynamic changes were related to symptom severity, possibly representing metabolic adaptations. [ABSTRACT FROM AUTHOR]

The neural network mediating successful response inhibition mainly includes right hemisphere activation of the pre‐supplementary motor area, inferior frontal gyrus (IFG), subthalamic nucleus (STN), and caudate nucleus. However, the causal role of these regions in the inhibitory network is undefined. Five patients with Parkinson's disease were assessed prior to and after therapeutic thermal ablation of the right STN in two separate functional magnetic resonance imaging (fMRI) sessions while performing a stop‐signal task. Initiation times were faster but motor inhibition with the left hand (contralateral to the lesion) was significantly impaired as evident in prolonged stop‐signal reaction times. Reduced inhibition after right subthalamotomy was associated (during successful inhibition) with the recruitment of basal ganglia regions outside the established inhibitory network. They included the putamen and caudate together with the anterior cingulate cortex and IFG of the left hemisphere. Subsequent network connectivity analysis (with the seed over the nonlesioned left STN) revealed a new inhibitory network after right subthalamotomies. Our results highlight the causal role of the right STN in the neural network for motor inhibition and the possible basal ganglia mechanisms for compensation upon losing a key node of the inhibition network. [ABSTRACT FROM AUTHOR]

Aims: To examine whether functional connectivity (FC) of the occipital gyrus differs between patients with Parkinson's disease (PD) motor subtypes and healthy controls (HCs). Methods: We enrolled 30 PD patients exhibiting tremor dominance (TD), 43 PD patients with postural instability and gait disturbance (PIGD), and 42 HCs. The occipital gyrus was partitioned into six areas of interest, as seed points, via the Anatomical Automatic Labeling template to compare the FC of the three groups and analyze the relationship of FC with clinical scales. Results: Compared with the PIGD group, the TD group showed increased FC between the left superior occipital gyrus (SOG.L) and right median cingulate and paracingulate gyri (DCG.R)/right paracentral lobule/bilateral inferior parietal, but supramarginal and angular gyri; the left middle occipital gyrus (MOG.L) and left posterior cingulate gyrus (PCG.L); the MOG.R and SOG.L/right calcarine fissure and surrounding cortex/DCG.R/PCG.L/right cuneus; the left inferior occipital gyrus (IOG.L) and right caudate nucleus; and the IOG.R and PCG.L. Conclusion: Differentiated FC between the occipital gyrus and other brain areas within the PD motor subtypes, which may serve as neural markers to distinguish between patients with TD and PIGD PD. [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]

Background and Objectives: This study was performed for the purpose of assessing whether antiepileptic levetiracetam treatment produces a change in brain volumes in children with epilepsy. To that end, we compared the volumes of the basal ganglia (caudate nucleus, putamen, globus, hip-pocampus, and thalamus) at magnetic resonance imaging (MRI) before and after treatment (months 18–24) in pediatric epilepsy patients using levetiracetam. Materials and Methods: This retrospective study involved a volumetric comparison of patients presenting to the Balikesir University Medical Faculty pediatric neurology clinic between 01.08.2019 and 01.11.2023 and diagnosed with epilepsy, and who underwent cranial MRI before and 18–24 months after treatment at the radiology department. The demographic and clinical characteristics (age, sex, family history of epilepsy, type of epilepsy, and EEG features (normal, abnormal, epileptiform)) of the patients included in the study were recorded. Results: The comparison of basal ganglia volumes at cranial MRI before and at months 18–24 of treatment revealed significant differences in the left caudate nucleus, right putamen, left putamen, left globus pallidus, right thalamus, left thalamus, and right hippocampal regions. Conclusions: In conclusion, differing findings are encountered at cranial imaging in patients with epilepsy, depending on the seizure frequency, activity, and the type of antiepileptic drugs used. This study compared basal ganglia volumes on cranial MRIs taken before and 18–24 months after treatment in pediatric epilepsy patients using levetiracetam. A significant increase was observed in the volumes of basal ganglia (caudate nucleus, putamen, globus pallidus, hippocampus, and thalamus) on the MRIs of pediatric epilepsy patients using levetiracetam. [ABSTRACT FROM AUTHOR]

BACKGROUND: There are differentially expressed genes in acute intracerebral hemorrhage, which are related to the occurrence and development of intracerebral hemorrhage OBJECTIVE: To screen differentially expressed genes and key genes in brain tissue of a rat model with acute intracerebral hemorrhage, to validate them through qPCR, and to analyze the relationships between key genes and the neurological function and brain tissue water content after intracerebral hemorrhage. METHODS: Seventy-eight Sprague-Dawley rats were randomly divided into two groups: in intracerebral hemorrhage group, a rat model of acute intracerebral hemorrhage was made using collagenase injection at the right caudate nucleus; and in sham-operated group, rats were injected with equal amount of saline at the same site. RNA was extracted from rat brain tissues of both groups using the TRIzol method and transcriptome sequencing technology was used to identify differentially expressed genes in brain tissues of acute intracerebral hemorrhage, which were then verified by qPCR and analyzed for the relationships between the genes and neurological function and brain tissue water content after intracerebral hemorrhage. And the key genes were analyzed by GO and KEGG functional enrichment analysis in combination with bioinformatics. RESULTS AND CONCLUSION: Ten key genes were identified, including CXCL8, SERPINE1, TFPI2, CXCR4, GDA, KCNQ5, ERICH3, SCN3B, CACNA1E, and CCL20. The contents of GDA, KCNQ5, ERICH3, SCN3B, and CACNA1E in the intracerebral hemorrhage group were lower than those in the sham-operated group (P < 0.05). The contents of CXCL8, SERPINE1, TFPI2, CXCR4 and CCL20 in the intracerebral hemorrhage group were higher than those in the sham-operated group (P < 0.05). The contents of GDA, KCNQ5, ERICH3, SCN3B, and CACNA1E were positively correlated with brain tissue water content and neurologic deficit score (P < 0.05), while the contents of CXCL8, SERPINE1, TFPI2, CXCR4 and CCL20 were negatively correlated with brain tissue water content and neurologic deficit score (P < 0.05). GO analysis indicated that differentially expressed genes were mainly enriched in two biological processes (leukocyte chemotaxis and chemokine-mediated signaling pathways), two cell components (cation channel complexes and ion channel complexes), and two molecular functions (gated channel activity and ion channel activity). KEGG analysis indicated that differentially expressed genes were concentrated in tumor necrosis factor signaling pathway, glutamatergic synapses and GABAergic synapses. To conclude, the differentially expressed genes in intracerebral hemorrhage include CXCL8, SERPINE1, TFPI2, CXCR4, GDA, KCNQ5, ERICH3, SCN3B, CACNA1E, and CCL20, and these genes are related to brain tissue water content and neurological function after intracerebral hemorrhage. These genes are mainly enriched in cell components, binding functions, cellular protrusions, and other related biological functions. [ABSTRACT FROM AUTHOR]

Diffusion Kurtosis Imaging (DKI)-derived metrics are recognized as indicators of maturation in neonates with low-grade germinal matrix and intraventricular hemorrhage (GMH-IVH). However, it is not yet known if these factors are associated with neurodevelopmental outcomes. The objective of this study was to acquire DKI-derived metrics in neonates with low-grade GMH-IVH, and to demonstrate their association with later neurodevelopmental outcomes. In this prospective study, neonates with low-grade GMH-IVH and control neonates were recruited, and DKI were performed between January 2020 and March 2021. These neonates underwent the Bayley Scales of Infant Development test at 18 months of age. Mean kurtosis (MK), radial kurtosis (RK) and gray matter values were measured. Spearman correlation analyses were conducted for the measured values and neurodevelopmental outcome scores. Forty controls (18 males, average gestational age (GA) 30 weeks ± 1.3, corrected GA at MRI scan 38 weeks ± 1) and thirty neonates with low-grade GMH-IVH (13 males, average GA 30 weeks ± 1.5, corrected GA at MRI scan 38 weeks ± 1). Neonates with low-grade GMH-IVH exhibited lower MK and RK values in the PLIC and the thalamus (P < 0.05). The MK value in the thalamus was associated with Mental Development Index (MDI) (r = 0.810, 95% CI 0.695–0.13; P < 0.001) and Psychomotor Development Index (PDI) (r = 0.852, 95% CI 0.722–0.912; P < 0.001) scores. RK value in the caudate nucleus significantly and positively correlated with MDI (r = 0.496, 95% CI 0.657–0.933; P < 0.001) and PDI (r = 0.545, 95% CI 0.712–0.942; P < 0.001) scores. The area under the curve (AUC) were used to assess diagnostic performance of MK and RK in thalamus (AUC = 0.866, 0.787) and caudate nucleus (AUC = 0.833, 0.671) for predicting neurodevelopmental outcomes. As quantitative neuroimaging markers, MK in thalamus and RK in caudate nucleus may help predict neurodevelopmental outcomes in neonates with low-grade GMH-IVH. [ABSTRACT FROM AUTHOR]

Past cross‐sectional chronic pain studies have revealed aberrant resting‐state brain activity in regions involved in pain processing and affect regulation. However, there is a paucity of longitudinal research examining links of resting‐state activity and pain resilience with changes in chronic pain outcomes over time. In this prospective study, we assessed the status of baseline (T1) resting‐state brain activity as a biomarker of later impairment from chronic pain and a mediator of the relation between pain resilience and impairment at follow‐up. One hundred forty‐two adults with chronic musculoskeletal pain completed a T1 assessment comprising a resting‐state functional magnetic resonance imaging scan based on regional homogeneity (ReHo) and self‐report measures of demographics, pain characteristics, psychological status, pain resilience, pain severity, and pain impairment. Subsequently, pain impairment was reassessed at a 6‐month follow‐up (T2). Hierarchical multiple regression and mediation analyses assessed relations of T1 ReHo and pain resilience scores with changes in pain impairment. Higher T1 ReHo values in the right caudate nucleus were associated with increased pain impairment at T2, after controlling for all other statistically significant self‐report measures. ReHo also partially mediated associations of T1 pain resilience dimensions with T2 pain impairment. T1 right caudate nucleus ReHo emerged as a possible biomarker of later impairment from chronic musculoskeletal pain and a neural mechanism that may help to explain why pain resilience is related to lower levels of later chronic pain impairment. Findings provide empirical foundations for prospective extensions that assess the status of ReHo activity and self‐reported pain resilience as markers for later impairment from chronic pain and targets for interventions to reduce impairment. Practitioner Points: Resting‐state markers of impairment: Higher baseline (T1) regional homogeneity (ReHo) values, localized in the right caudate nucleus, were associated with exacerbations in impairment from chronic musculoskeletal pain at a 6‐month follow‐up, independent of T1 demographics, pain experiences, and psychological factors.Mediating role of ReHo values: ReHo values in the right caudate nucleus also mediated the relationship between baseline pain resilience levels and later pain impairment among participants.Therapeutic implications: Findings provide empirical foundations for research extensions that evaluate (1) the use of resting‐state activity in assessment to identify people at risk for later impairment from pain and (2) changes in resting‐state activity as biomarkers for the efficacy of treatments designed to improve resilience and reduce impairment among those in need. [ABSTRACT FROM AUTHOR]

Background: Dual-phase fluorine-18 labeled N-3-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) nortropane (18F-FP-CIT) positron emission tomography (PET) scans could be used to support disorders like Parkinson's disease (PD). Dopamine transporter (DAT) binding and cerebral perfusion are associated with ageing and gender. We investigated the effects of age and gender on non-degenerative parkinsonism, using automated quantification in striatum: specific binding ratios (SBRs) for DAT binding in delayed phase PET (dCIT) and standardized-uptake-value ratios (SUVRs) for cerebral perfusion in early phase PET (eCIT). We also examined the correlations between SBR and SUVR. Methods: This retrospective study analyzed subjects with dual-phase 18F-FP-CIT PET scans. The eCIT images were acquired immediately post-injection, and dCIT images were taken 120 min later. With Brightonix software, automated quantification of SBRs for dCIT and SUVRs for eCIT were acquired from visually normal scans. The effects of aging and gender were assessed by regressing SBRs and SUVRs on age for both genders. The correlations between SUVRs and SBRs were evaluated. Results: We studied 79 subjects (34 males and 45 females). An age-related reduction in SBRs was observed in the dorsal striatum, ventral striatum, caudate nucleus, and putamen for both genders. SUVRs were found to negatively correlate with age in the dorsal striatum, ventral striatum, caudate nucleus, and putamen for males and in the dorsal striatum and caudate nucleus for females. Positive correlations between SBRs and SUVRs in the dorsal striatum, ventral striatum, caudate nucleus, and putamen for male and in the dorsal striatum, caudate nucleus, and putamen for females. Conclusions: Using quantified values from dual-phase 18F-FP-CIT PET with a single injection, we demonstrate a negative impact of age on SBRs (DAT binding) in the striatum for both genders and SUVRs (cerebral perfusion) in the dorsal striatum and caudate nucleus for both genders and in the ventral striatum and putamen for males. Additionally, we found positive associations between SBR and SUVR values in the dorsal striatum, caudate nucleus, and putamen for both genders and in the ventral striatum for males. [ABSTRACT FROM AUTHOR]

Evidence suggests that subcortical structures play a role in high-level cognitive functions such as the allocation of spatial attention. While there is abundant evidence in humans for posterior alpha band oscillations being modulated by spatial attention, little is known about how subcortical regions contribute to these oscillatory modulations, particularly under varying conditions of cognitive challenge. In this study, we combined MEG and structural MRI data to investigate the role of subcortical structures in controlling the allocation of attentional resources by employing a cued spatial attention paradigm with varying levels of perceptual load. We asked whether hemispheric lateralization of volumetric measures of the thalamus and basal ganglia predicted the hemispheric modulation of alpha-band power. Lateral asymmetry of the globus pallidus, caudate nucleus, and thalamus predicted attention-related modulations of posterior alpha oscillations. When the perceptual load was applied to the target and the distractor was salient caudate nucleus asymmetry predicted alpha-band modulations. Globus pallidus was predictive of alpha-band modulations when either the target had a high load, or the distractor was salient, but not both. Finally, the asymmetry of the thalamus predicted alpha band modulation when neither component of the task was perceptually demanding. In addition to delivering new insight into the subcortical circuity controlling alpha oscillations with spatial attention, our finding might also have clinical applications. We provide a framework that could be followed for detecting how structural changes in subcortical regions that are associated with neurological disorders can be reflected in the modulation of oscillatory brain activity. [ABSTRACT FROM AUTHOR]

AbstractObjective: Previous studies have suggested a link between dysregulation of cortical iron levels and neuronal loss in amyotrophic lateral sclerosis (ALS) patients. However, few studies have reported differences in quantitative susceptibility mapping (QSM) values in subcortical nuclei between patients with ALS and healthy controls (HCs). Methods: MRI was performed using a 3 Tesla Prisma scanner (64-channel head coil), including 3D T1-MPRAGE and multi-echo 3D GRE for QSM reconstruction. Automated QSM segmentation was used to measure susceptibility values in the subcortical nuclei, which were compared between the groups. Correlations with clinical scales were analyzed. Group comparisons were performed using independent t-tests, with p < 0.05 considered significant. Correlations were assessed using Pearson’s correlation, with p < 0.05 considered significant. Cohen’s d was reported to compare the standardized mean difference (SMD) of QSM. Results: Twelve patients with limb-onset ALS (mean age 48.7 years, 75% male) and 13 age-, sex-, and handedness-matched HCs (mean age 44.6 years, 69% male) were included. Compared to HCs, ALS patients demonstrated significantly lower susceptibility in the left caudate nucleus (CN) (SMD = −0.845), right CN (SMD = −0.851), whole CN (SMD = −1.016), and left subthalamic nucleus (STN) (SMD = −1.000). Susceptibility in the left putamen (SMD = −0.857), left thalamus (SMD = −1.081), and whole thalamus (SMD = −0.968) was significantly higher in the patients. The susceptibility of the substantia nigra (SN), CN, and pulvinar was positively correlated with disease duration. Conclusions: QSM detects abnormal iron accumulation patterns in the subcortical gray matter of ALS patients, which correlates with disease characteristics, supporting its potential as a neuroimaging biomarker. [ABSTRACT FROM AUTHOR]

Background: Recent research has demonstrated that the dorsal striatum is directly associated with the integration of cognitive, sensory-motor, and motivational/emotional data. Disruptions in the corticostriatal circuit have been implicated in the pathophysiology of psychosis. The dorsal striatum was reported to show lateralized pathology in psychotic disorders. In this study, we aimed to analyze the laterality of the dorsal striatum with texture analysis of T2-weighted magnetic resonance imaging (MRI) images from schizoaffective disorder (SAD) patients. Methods: Twenty SAD patients, met the inclusion criteria and had available cranial MRI data were assigned as the patient group. Twenty healthy individuals were determined as the control group. Texture analysis values were obtained from striatum region of interests (ROI) generated from T2-weighted MRI images. Data are presented as mean and standard deviation. The suitability of the data for normal distribution was analyzed with the Kolmogorov-Smirnov test. Analysis of variance (ANOVA) test (Post Hoc TUKEY) was employed to compare the group data based on test findings. Results: There was no significant difference between the groups in terms of gender and age. There were differences in the values of texture analysis parameters of both caudate and putamen nuclei in comparison to controls. We identified differences in the left dorsal striatum nuclei in SAD. The differences in the putamen were more and more pronounced than in the caudate. Conclusions: Texture analyses suggest that the left dorsal striatum nuclei may be different in SAD patients. Further studies are needed to determine the pathophysiology of SAD and how it may affect disease treatment. [ABSTRACT FROM AUTHOR]

Degenerative lesions specific to the basal nuclei have not been described as a background finding in Beagle dogs. This report comprises a documentation of seven cases. In the context of a nonclinical safety studies, the authors suggest documenting the lesion descriptively as degeneration neuropil, basal nuclei, bilateral as it is characterized by (1) vacuolation, neuropil; (2) gliosis (astro- and/or microgliosis); and (3) demyelination. This novel lesion is considered a potential new background change for several reasons: (1) It occurred in animals from test item–treated and also vehicle-treated groups; (2) no dose dependency was observed; (3) in one of six affected test item–treated dogs, the given compound was shown not to penetrate the blood-brain barrier; and (4) statistical comparison between the proportions of affected dogs in the treatment and control groups did not yield a statistically significant difference. The etiology remains unknown and is subject to further investigations. [ABSTRACT FROM AUTHOR]

• Clamping of the umbilical cord during caesarean delivery of piglets recapitulates moderate birth asphyxia (ASP) of human neonates. • ASP impairs the early development of motor functions. • ASP induces death of CTIP2+-neurons in the motor cortex and caudate and arrests the maturation of oligodendrocyte precursor cells. • Dietary plasma mitigates ASP-induced encephalopathy by induction of anti-inflammatory, anti-oxidative, and neuroprotective mechanisms. • Dietary plasma may be a source of neuroprotective bioactive elements. Newborns exposed to birth asphyxia transiently experience deficient blood flow and a lack of oxygen, potentially inducing hypoxic-ischaemic encephalopathy and subsequent neurological damage. Immunomodulatory components in plasma may dampen these responses. Using caesarean-delivered pigs as a model, we hypothesized that dietary plasma supplementation improves brain outcomes in pigs exposed to birth asphyxia. Mild birth asphyxia was induced by temporary occlusion of the umbilical cord prior to caesarean delivery. Motor development was assessed in asphyxiated (ASP) and control (CON) piglets using neonatal arousal, physical activity and gait test parameters before euthanasia on Day 4. The ASP pigs exhibited increased plasma lactate at birth, deficient motor skills and increased glial fibrillary acidic protein levels in CSF and astrogliosis in the putamen. The expression of genes related to oxidative stress, inflammation and synaptic functions was transiently altered in the motor cortex and caudate nucleus. The number of apoptotic cells among CTIP2-positive neurons in the motor cortex and striatal medium spiny neurons was increased, and maturation of preoligodendrocytes in the internal capsule was delayed. Plasma supplementation improved gait performance in the beam test, attenuated neuronal apoptosis and affected gene expression related to neuroinflammation, neurotransmission and antioxidants (motor cortex, caudate). We present a new clinically relevant animal model of moderate birth asphyxia inducing structural and functional brain damage. The components in plasma that support brain repair remain to be identified but may represent a therapeutic potential for infants and animals after birth asphyxia. [ABSTRACT FROM AUTHOR]

Depression is a chronic psychiatric disorder related to diminished dopaminergic neurotransmission. Deep brain stimulation (DBS) has shown effectiveness in treating patients with treatment-refractory depression (TRD). This study aimed to evaluate the effect of DBS on dopamine D2 receptor binding in patients with TRD. Six patients with TRD were treated with bed nucleus of the stria terminalis (BNST)-nucleus accumbens (NAc) DBS were recruited. Ultra-high sensitivity [11C]raclopride dynamic total-body positron emission tomography (PET) imaging was used to assess the brain D2 receptor binding. Each patient underwent a [11C]raclopride PET scan for 60-min under DBS OFF and DBS ON, respectively. A simplified reference tissue model was used to generate parametric images of binding potential (BP ND) with the cerebellum as reference tissue. Depression and anxiety symptoms improved after 3–6 months of DBS treatment. Compared with two-day-nonstimulated conditions, one-day BNST-NAc DBS decreased [11C]raclopride BP ND in the amygdala (15.9 %, p < 0.01), caudate nucleus (15.4 %, p < 0.0001) and substantia nigra (10.8 %, p < 0.01). This study was limited to the small sample size and lack of a healthy control group. Chronic BNST-NAc DBS improved depression and anxiety symptoms, and short-term stimulation decreased D2 receptor binding in the amygdala, caudate nucleus, and substantia nigra. The findings suggest that DBS relieves depression and anxiety symptoms possibly by regulating the dopaminergic system. • BNST-NAc DBS can improve the depressive and anxiety symptoms of TRD patients. • BNST-NAc DBS decreased dopamine D2 receptor binding in the amygdala, caudate, and substantia nigra. • BNST-NAc DBS improves clinical symptoms of TRD patients potentially by compensating for the defective dopaminergic system. [ABSTRACT FROM AUTHOR]

Objective: Lower white matter integrity of frontal-subcortical circuitry has been associated with late-life depression in normally aging older adults and with the presence of multiple sclerosis (MS). Frontal-striatal white matter tracts involved in executive, cognitive, emotion, and motor function may underlie depression in older adults with MS. The present study examined the association between depression score and frontal-striatal white matter integrity in older adults with MS and controls. Methods: Older adults with MS (OAMS) (n = 67, mean age = 64.55 ± 3.89) and controls (n = 74, mean age = 69.04 ± 6.32) underwent brain MRI, cognitive assessment, psychological, and motoric testing. Depression was assessed through the 30-item Geriatric Depression Scale. Fractional anisotropy (FA) was extracted from two bilateral tracts: dorsolateral prefrontal cortex to putamen nucleus (DLPFC-pn) and dorsolateral prefrontal cortex to caudate nucleus (DLPFC-cn). Results: OAMS reported significantly worse (i.e., higher) depression symptoms (β =.357, p <.001) compared to healthy controls. Adjusted moderation analyses revealed, via group by FA interactions, significantly stronger associations between FA of the left DLPFC-pn tract and total depression (B = − 61.70, p =.011) among OAMS compared to controls. Conditional effects revealed that lower FA of the left DLPFC-pn was significantly associated with worse (i.e., higher) depression symptoms (b = − 38.0, p =.028) only among OAMS. The other three tracts were not significant in moderation models. Conclusions: We provided first evidence that lower white matter integrity of the left DLPFC-pn tract was related to worse depression in older adults with MS. [ABSTRACT FROM AUTHOR]

Three‐dimensional morphometric data better show the structural and functional characteristics of the brain. The objective of this study was to estimate the volume of the cerebral structures of the sheep using design‐based stereology. The brains of five sheep were used, fixed in formalin 10% and embedded in agar 6%. An average of 10–12 slab was obtained from each brain. All slabs were stained using Mulligan's method and photographs were recorded. The volume of the brain and its structures were estimated using the Cavalieri's estimator and the point counting system. The total volume was 70604.8 ± 132.45 mm3. The volume fractions of the grey and white matters were calculated as 42.55 ± 0.21% and 24.23 ± 0.51% of the whole brain, respectively. The fractional volume of the caudate nucleus and claustrum were estimated at 2.39 ± 0.08% and at 1.008 ± 0.057% of total brain volume. The volumes of corpus callosum, internal capsule and external capsule were 1.24 ± 0.053%, 3.63 ± 0.22% and 0.698 ± 0.049% of total cerebral volume, respectively. These data could help improve the veterinary comparative neuroanatomy knowledge and development of experimental studies in the field. [ABSTRACT FROM AUTHOR]

Dental drilling sounds can induce anxiety in some patients. This study aimed to use functional magnetic resonance imaging (fMRI) to assess the relationship between dental fear and auditory stimuli. Thirty-four right-handed individuals (21 women and 13 men; average age, 31.2 years) were selected. The level of dental fear was assessed using the dental fear survey (DFS). Based on a threshold DFS score > 52, participants were categorized into two groups: dental fear (DF) group (n = 12) and control group (n = 22). Two types of stimuli were presented in a single session: dental and neutral sounds. Cerebral activation during the presentation of these sounds was evaluated using contrast-enhanced blood oxygenation level-dependent fMRI. In the DF group, dental sounds induced significantly stronger activation in the left inferior frontal gyrus and left caudate nucleus (one-sample t test, P < 0.001). In contrast, in the control group, significantly stronger activation was observed in the bilateral Heschl's gyri and left middle frontal gyrus (one-sample t test, P < 0.001). Additionally, a two-sample t test revealed that dental sounds induced a significantly stronger activation in the left caudate nucleus in the DF group than in the control group (P < 0.005). These findings suggest that the cerebral activation pattern in individuals with DF differs from that in controls. Increased activation of subcortical regions may be associated with sound memory during dental treatment. [ABSTRACT FROM AUTHOR]

When a single choice impacts on life outcomes, faculties to make ethical judgments come into play. Here we studied decisions in a real-life setting involving life-and-death outcomes that affect others and the decision-maker as well. We chose a genuine situation where prior training and expertise play a role: firefighting in life-threatening situations. By studying the neural correlates of dilemmas involving life-saving decisions, using realistic firefighting situations, allowed us to go beyond previously used hypothetical dilemmas, while addressing the role of expertise and the use of coping strategies (n = 47). We asked the question whether the neural underpinnings of deontologically based decisions are affected by expertise. These realistic life-saving dilemmas activate the same core reward and affective processing network, in particular the ventromedial prefrontal cortex, nucleus accumbens and amygdala, irrespective of prior expertise, thereby supporting general domain theories of ethical decision-making. We found that brain activity in the hippocampus and insula parametrically increased as the risk increased. Connectivity analysis showed a larger directed influence of the insula on circuits related to action selection in non-experts, which were slower than experts in non rescuing decisions. Relative neural activity related to the decision to rescue or not, in the caudate nucleus, insula and anterior cingulate cortex was negatively associated with coping strategies, in experts (firefighters) suggesting practice-based learning. This shows an association between activity and expert-related usage of coping strategies. Expertise enables salience network activation as a function of behavioural coping dimensions, with a distinct connectivity profile when facing life-rescuing dilemmas. [ABSTRACT FROM AUTHOR]

Objective: Patients with borderline personality disorder (BPD) report to be especially prone to social emotions like shame and guilt. At the same time, these emotions seem to play an important role in BPD pathology. The present study aimed to deepen the knowledge about the processes behind shame and guilt in patients with BPD. Methods: Twenty patients with BPD and twenty healthy controls (HCs) took part in an experiment that induced shame and guilt by imagining scenarios during scanning using functional brain imaging. Participants also filled out self-report questionnaires and took part in diagnostic interviews. Results: BPD patients reported more proneness to guilt but not to shame than the HCs. There was no difference in the self-reported intensity rating of experimentally induced emotions between the groups. Between-group contrast of neural signals in the shame condition revealed a stronger activation of cingulate and fusiform gyrus for the BPD patients compared to the controls, and a more pronounced activation in the lingual gyrus and cuneus for the HCs. In the guilt condition, activation in the caudate nucleus, the fusiform gyrus, and the posterior cingulate cortex was stronger in BPD patients, while HC showed stronger activations in cuneus, lingual gyrus, and fronto-temporal regions. Conclusions: Differences in the neuro-functional processes between BPD patients and HC were found, even though the two groups did not differ in their self-report of subjective proneness to guilt and emotional intensity of shame and guilt during the experiment. While the HCs may be engaged more by the emotional scenarios themselves, the BPD patients may be more occupied with cognitive regulatory and self-referential processing. [ABSTRACT FROM AUTHOR]

A preserved sense of smell and taste allows us to understand many environmental "messages" and results in meaningfully improvements to quality of life. With the COVID-19 pandemic, it became clear how important these senses are for social and nutritional status and catapulted this niche chemosensory research area towards widespread interest. In the current exploratory work, we assessed two groups of post-COVID-19 patients who reported having had (Group 1) or not (Group 2) a smell/taste impairment at the disease onset. The aim was to compare them using validated smell and taste tests as well as with brain magnetic resonance imaging volumetric analysis. Normative data were used for smell scores comparison and a pool of healthy subjects, recruited before the pandemic, served as controls for taste scores. The majority of patients in both groups showed an olfactory impairment, which was more severe in Group 1 (median UPSIT scores: 24.5 Group 1 vs 31.0 Group 2, p = 0.008), particularly among women (p = 0.014). No significant differences emerged comparing taste scores between Group 1 and Group 2, but dysgeusia was only present in Group 1 patients. However, for taste scores, a significant difference was found between Group 1 and controls (p = 0.005). No MRI anatomical abnormalities emerged in any patients while brain volumetric analysis suggested a significant difference among groups for the right caudate nucleus (p = 0.028), although this was not retained following Benjamini–Hochberg correction. This exploratory study could add new information in COVID-19 chemosensory long-lasting impairment and address future investigations on the post-COVID-19 patients' research. [ABSTRACT FROM AUTHOR]

A total of 3102 neurons were recorded before and following acute and chronic methylphenidate (MPD) administration. Acute MPD exposure elicits mainly increases in neuronal and behavioral activity in dose–response characteristics. The response to chronic MPD exposure, as compared to acute 0.6, 2.5, or 10.0 mg/kg MPD administration, elicits electrophysiological and behavioral sensitization in some animals and electrophysiological and behavioral tolerance in others when the neuronal recording evaluations were performed based on the animals' behavioral responses, or amount of locomotor activity, to chronic MPD exposure. The majority of neurons recorded from those expressing behavioral sensitization responded to chronic MPD with further increases in firing rate as compared to the initial MPD responses. The majority of neurons recorded from animals expressing behavioral tolerance responded to chronic MPD with decreases in their firing rate as compared to the initial MPD exposures. Each of the six brain areas studied—the ventral tegmental area, locus coeruleus, dorsal raphe, nucleus accumbens, prefrontal cortex, and caudate nucleus (VTA, LC, DR, NAc, PFC, and CN)—responds significantly (p < 0.001) differently to MPD, suggesting that each one of the above brain areas exhibits different roles in the response to MPD. Moreover, this study demonstrates that it is essential to evaluate neuronal activity responses to psychostimulants based on the animals' behavioral responses to acute and chronic effects of the drug from several brain areas simultaneously to obtain accurate information on each area's role in response to the drug. [ABSTRACT FROM AUTHOR]