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α‐Melanocyte stimulating hormone (α‐MSH) is a peptide hormone released from the intermediate lobe of the pituitary which regulates body pigmentation. In addition to the pituitary, α‐MSH is also produced in the midbrain, and exerts both anorexigenic and an anxiogenic actions. Acyl ghrelin and cholecystokinin are peripheral hormones derived from the digestive tract which affect the brain to control food intake and feeding behavior in vertebrates. In the present study, hypothesizing that plasma α‐MSH may also stimulate the brain and exert central effects, we examined whether peripherally administered α‐MSH affects food intake and psychomotor activity using a goldfish model. Intraperitoneal (IP) administration of α‐MSH at 100 pmol g−1 body weight (BW) reduced food consumption and enhanced thigmotaxis. These α‐MSH‐induced actions were blocked by intracerebroventricular administration of HS024, an antagonist of the melanocortin 4 receptor (MC4R), at 50 pmol g−1 BW, whereas these actions were not attenuated by pretreatment with an IP‐injected excess amount of capsaicin, a neurotoxin that destroys primary sensory (vagal and splanchnic) afferents, at 160 nmol g−1 BW. Transcripts for the MC4R showed higher expression in the diencephalon in other regions of the brain. These results suggest that, in goldfish, IP administered α‐MSH is taken up by the brain, and also acts as anorexigenic and anxiogenic factor via the MC4R signaling pathway. [ABSTRACT FROM AUTHOR]

The central opioid system and dopaminergic activity in mammals play key roles in mediating social reward, impulsivity, cognition, decision making, and motivation for learning and social interactions. Repeated positive fighting experiences enhance the gene expression levels of μ‐type opioid receptor (Mor), tyrosine hydroxylase (Th), an enzyme involved in dopamine synthesis, and dopamine receptor type 2 (D2r) in the reward‐related brain regions of aggressive mice. However, it remains unclear whether the opioid system and dopaminergic activity are associated with repeated winning in fish. In this study, we investigated changes in the expression levels of Mor, Th1, and D2r in different regions of the brain of adult medaka Oryzias latipes males after intermittent and continuous fight for 3 days. When a pair of males was provided a fighting opportunity for 20 min per day, we noted that within the 3‐day observation period, aggressive winning males showed significantly higher expression levels of Mor in telencephalon and diencephalon, Th1 in diencephalon, and D2r in telencephalon than subordinate losing males. However, no such differences in gene expression level were observed between winning and losing males in the 3‐day continuous fight. Further, no differences were detected in the total number of aggressive actions among the winners from each fighting test. However, the total number of “chase” actions, with a stronger aggressiveness index, was higher for the repeated winning male in the three‐time intermittent fight than for the winner in the 3‐day continuous fight. These findings suggest that repeated intermittent winning experiences with strong aggressiveness could be perceived as a reward by O. latipes males. [ABSTRACT FROM AUTHOR]

During paradoxical sleep (PS, aka REM sleep) the cerebral cortex displays rapid electroencephalographic activity similar to that of wakefulness, whereas in the posterior associative thalamus, rapid activity is interrupted by frequent periods of slow‐wave (delta) oscillations at 2–3 Hz, thereby dissociating the intrinsic frequency in thalamus and cortex. Here we studied the functional consequences of such a dissociation using intrathalamic and intracortical recordings in 21 epileptic patients, applying coherence analysis to examine changes in functional connectivity between the posterior thalamus (mainly medial pulvinar) and six cortical functional networks, and also between each cortical network with respect to the others. Periods of slow‐wave thalamic activity ('delta PS') were more prevalent than phases of 'rapid PS,' and the delta/rapid thalamic alternance did not overlap with the classical tonic/phasic dichotomy based on rapid eye movements. Thalamo‐cortical and cortico‐cortical functional connectivity significantly decreased during delta PS, relative to both rapid PS periods and to wakefulness. The fact that delta thalamic activity and low thalamo‐cortical binding coincided with a suppression of cortico‐cortical connectivity supports a crucial role for the posterior associative thalamus, and particularly the medial pulvinar, in ensuring trans‐thalamic communication between distant cortical areas. Disruption of such a trans‐thalamic communication during delta PS compromises the functional binding between cortical areas, and consequently might contribute to the alteration of perceptual experiences commonly reported during dreams. Key points: During paradoxical, or REM, sleep (PS), rapid thalamic activity is interrupted by frequent periods of slow delta waves at 2–3 Hz.During these periods of thalamic delta activity there was a drastic drop of functional connectivity between associative thalamus and cortex, and also among different cortical networks.The delta/rapid alternance did not overlap with the classically defined 'tonic/phasic' periods and therefore suggests a distinct dichotomy of functional states in PS.Recurrent decrease in thalamo‐cortical and cortico‐cortical functional connectivity during PS may compromise the spatio‐temporal binding between cortical areas, which in turn could hinder the formation of coherent mental content during dreams. [ABSTRACT FROM AUTHOR]

Exposure to repetitive head impacts in contact sports is associated with neurodegenerative disorders including chronic traumatic encephalopathy (CTE), which currently can be diagnosed only at post-mortem. American football players are at higher risk of developing CTE given their exposure to repetitive head impacts. One promising approach for diagnosing CTE in vivo is to explore known neuropathological abnormalities at post-mortem in living individuals using structural MRI. MRI brain morphometry was evaluated in 170 male former American football players ages 45–74 years (n = 114 professional; n = 56 college) and 54 same-age unexposed asymptomatic male controls (n = 54, age range 45–74). Cortical thickness and volume of regions of interest were selected based on established CTE pathology findings and were assessed using FreeSurfer. Group differences and interactions with age and exposure factors were evaluated using a generalized least squares model. A separate logistic regression and independent multinomial model were performed to predict each traumatic encephalopathy syndrome (TES) diagnosis, core clinical features and provisional level of certainty for CTE pathology using brain regions of interest. Former college and professional American football players (combined) showed significant cortical thickness and/or volume reductions compared to unexposed asymptomatic controls in the hippocampus, amygdala, entorhinal cortex, parahippocampal gyrus, insula, temporal pole and superior frontal gyrus. Post hoc analyses identified group-level differences between former professional players and unexposed asymptomatic controls in the hippocampus, amygdala, entorhinal cortex, parahippocampal gyrus, insula and superior frontal gyrus. Former college players showed significant volume reductions in the hippocampus, amygdala and superior frontal gyrus compared to the unexposed asymptomatic controls. We did not observe Age × Group interactions for brain morphometric measures. Interactions between morphometry and exposure measures were limited to a single significant positive association between the age of first exposure to organized tackle football and right insular volume. We found no significant relationship between brain morphometric measures and the TES diagnosis core clinical features and provisional level of certainty for CTE pathology outcomes. These findings suggested that MRI morphometrics detect abnormalities in individuals with a history of repetitive head impact exposure that resemble the anatomic distribution of pathological findings from post-mortem CTE studies. The lack of findings associating MRI measures with exposure metrics (except for one significant relationship) or TES diagnosis and core clinical features suggested that brain morphometry must be complemented by other types of measures to characterize individuals with repetitive head impacts. [ABSTRACT FROM AUTHOR]

Cocaine is a frequently abused and highly addictive drug that damages brain health and imposes substantial social and economic costs. Acupuncture has been used in the treatment of cocaine addiction and has been shown to improve abnormal mental and motor states. This article mainly focuses on the neurobiological mechanisms involving the central nervous system (CNS) and peripheral nervous system (PNS) that underlie the effects of acupuncture in the treatment of cocaine addiction. The central dopamine system is a key player in acupuncture treatment of cocaine addiction; the ventral tegmental area (VTA)—nucleus accumbens (NAc) signaling pathway, which has a modulatory influence on behavior and psychology after chronic use of cocaine, is a significant target of acupuncture action. Moreover, acupuncture alleviates cocaine-induced seizures or acute psychomotor responses through the paraventricular thalamus and the lateral habenula (LHb)—rostromedial tegmental (RMTg) nucleus circuits. The data suggest that acupuncture can impact various cocaine-induced issues via stimulation of diverse brain areas; nevertheless, the interconnection of these brain regions and the PNS mechanisms involved remain unknown. In this review, we also discuss the effects of specific acupuncture protocols on cocaine addiction and note that variations in needling modalities, current intensities and traditional acupuncture point locations have led to different experimental results. Therefore, standardized acupuncture protocols (with respect to stimulation methods, point locations and number of sessions) may become particularly important in future studies. [ABSTRACT FROM AUTHOR]

The hypothalamic peptide orexin has a prominent role in arousal-related processes. Parvalbumin (PV) positive neurons, as one of the most important subtypes of γ-aminobutyric acid (GABA) interneurons, which also participate in sleep-wake regulation. To broaden the understanding of the neural control and connection between these two types of neurons in the sleep associated nuclei, a double-label immunohistochemical method was used to investigate the overlap between PV immunopositive distributions and projections of orexin neurons in mouse brain. In the basal forebrain, overlap was observed in the nucleus accumbens shell (AcbSh), the nucleus of the horizontal limb of the diagonal band (HDB), magnocellular preoptic nucleus (MCPO), substantia innominata (SI), but avoided the nucleus accumbens core (AcbC). In the diencephalon, this dual innervation extended in the direction near the edge of the 3rd ventricle (3 V) to the ventrolateral preoptic nucleus (VLPO), although the density of PV neurons there was somewhat lighter. Orexin immunoreactive neurons in several lateral hypothalamic areas (LH) were embedded within dense clusters of PV processes when the buttons of orexin were in obvious contact with PV immunoreactivity. In the remainder of hypothalamus, mainly including the ventral tuberomammillary nucleus (VTM), there were few fine orexin fibers and buttons contact with PV soma. Intermingled orexin and PV immunoreactivity were observed in the ventral tegmental area (VTA), and sparse overlap was observed in the ventrolateral periaqueductal gray (VLPAG) and laterodorsal tegmental nucleus (LDT) in the brainstem. Thus, these two different types of neurons, originating in different parts of the brain, together target several brain regions and brainstem monoaminergic nuclei involved in the roles of motivation, stress, locomotion, especially in the regulation of sleep. [ABSTRACT FROM AUTHOR]

In current study, we used Nissl staining to examine the histological structure of the juvenile Chinese alligator brain, and immunohistochemistry (IHC) staining to detail the serotonin (5-hydroxytryptamine, 5-HT) localization and morphology of neurons belonging to the serotonergic system. Nissl staining revealed that the Chinese alligator brain was divided into four regions (telencephalon, diencephalon, brainstem, and cerebellum) and a connected ventricular system (containing the pair of lateral ventricles, third ventricle, fourth ventricle and the aqueduct). According to the IHC results, 5-HT immunoreactive (5-HT-IR) neurons were primarily observed in the cerebral cortex, the hypothalamic paraventricular nucleus (PH), tectum and tegmentum of the optic lobes, the medial longitudinal fasciculus (Flm) of medulla oblongata and the cerebellar cortex. 5-HT-IR fibers were mostly located lateral to the hypothalamic paraventricular nucleus (PH), in the medial vestibular nucleus (MVe) of the medulla oblongata, and in the choroid plexus (CP) of the lateral ventricles. Additionally, our findings paralleled those results of other reptiles; nevertheless, some distinctions in terms of both histological architecture and function were identified. The layering of the cerebral cortex and tectum, as well as the arrangement of Purkinje cells, differed between reptile brains. The distribution of 5-HT-IR neurons varied in the layer of cerebral and cerebellar cortex when compared to other reptiles. Within the diencephalon, 5-HT-IR neurons formed distinct nuclei in the hypothalamic paraventricular nucleus (PH), but few in the infundibular recess. [ABSTRACT FROM AUTHOR]

We report on a previously healthy zoo specimen of an adult budgerigar (Melopsittacus undulatus, obtainedwithpermission fromSouthwick'sZoo) founddeceased in its enclosure. To assess cause of death and ensure the absence of an infectious neoplasia, we used an integrated multiscale brain-imaging workflow, previously only used on mammals. The specimen was imaged with microcomputed tomography before and after enhancing soft-tissue contrast with diffusible iodine-based contrast-enhanced microcomputed tomography. Scans revealed an orbital blowout fracture and an unidentified large mass across majority of the diencephalon, striatum and midbrain caudal to the right orbit. After destaining, neural pathohistology confirmed the mass as a brain haemorrhage with no evidence of neoplasia or inflammation. We conclude that this specimen died of head trauma, likely from a head-on collision within its enclosure. This multiscale imaging workflow (diffusible iodine-based contrast-enhanced microcomputed tomography followed by destaining and pathohistology) can improve our evaluation of differential diagnoses in avian specimens. [ABSTRACT FROM AUTHOR]

Abstract Background The significant role of embryonic cerebrospinal fluid (eCSF) in the initial stages of brain development has been thoroughly studied. This fluid contains crucial molecules for proper brain development such as members of the Wnt and FGF families, apolipoproteins, and retinol binding protein. Nevertheless, the source of these molecules remains uncertain since they are present before the formation of the choroid plexus, which is conventionally known as the primary producer of cerebrospinal fluid. The subcommissural organ (SCO) is a highly conserved gland located in the diencephalon and is one of the earliest differentiating brain structures. The SCO secretes molecules into the eCSF, prior to the differentiation of the choroid plexus, playing a pivotal role in the homeostasis and dynamics of this fluid. One of the key molecules secreted by the SCO is SCO-spondin, a protein involved in maintenance of the normal ventricle size, straight spinal axis, neurogenesis, and axonal guidance. Furthermore, SCO secretes transthyretin and basic fibroblast growth factor 2, while other identified molecules in the eCSF could potentially be secreted by the SCO. Additionally, various transcription factors have been identified in the SCO. However, the precise mechanisms involved in the early SCO development are not fully understood. Results To uncover key molecular players and signaling pathways involved in the role of the SCO during brain development, we conducted a transcriptomic analysis comparing the embryonic chick SCO at HH23 and HH30 stages (4 and 7 days respectively). Additionally, a public transcriptomic data from HH30 entire chick brain was used to compare expression levels between SCO and whole brain transcriptome. These analyses revealed that, at both stages, the SCO differentially expresses several members of bone morphogenic proteins, Wnt and fibroblast growth factors families, diverse proteins involved in axonal guidance, neurogenic and differentiative molecules, cell receptors and transcription factors. The secretory pathway is particularly upregulated at stage HH30 while the proliferative pathway is increased at stage HH23. Conclusion The results suggest that the SCO has the capacity to secrete several morphogenic molecules to the eCSF prior to the development of other structures, such as the choroid plexus.

Background: Mouse brains can contain specific polyglucosan aggregates known as Periodic Acid-Schiff (PAS)-granules. Generated in astrocytes, these granules increase with age and exhibit neo-epitopes of carbohydrate nature that are recognized by natural IgM antibodies (IgMs). The existence of neoepitopes on PAS granules suggests the presence of neoepitopes in other brain structures, and this is investigated here. To this end, brain sections from SAMP8 and ICR-CD1 mice were examined at different ages. Results: We have identified two novel structures that, apart from PAS granules, are recognized by natural IgMs. On one side, IgM reactive (IgM+) granular structures which are placed in the longitudinal fissure, the quadrigeminal cistern, and a region that extends from the quadrigeminal cistern to the interpeduncular cistern. This last region, located between the telencephalon and both the mesencephalon and diencephalon, is designated henceforth as the fissura magna, as it is indeed a fissure and the largest in the brain. As all these regions are extraparenchymal (EP), the IgM+ granules found in these zones have been named EP granules. These EP granules are mainly associated with fibroblasts and are not stained with PAS. On the other side, some IgM+ astrocytes have been found in the glia limitans, near the above-mentioned fissures. Remarkably, EP granules are more prevalent at younger ages, while the number of IgM+ astrocytes increases with age, similarly to the already described evolution of PAS granules. Conclusions: The present work reports the presence of two brain-related structures that, apart from PAS granules, contain neo-epitopes of carbohydrate nature, namely EP granules and IgM+ astrocytes. We suggest that EP granules, associated to fibroblasts, may be part of a physiological function in brain clearance or brain-CSF immune surveillance, while both PAS granules and IgM+ astrocytes may be related to the increasing accumulation of harmful materials that occurs with age and linked to brain protective mechanisms. Moreover, the specific localisation of these EP granules and IgM+ astrocytes suggest the importance of the fissura magna in these brain-related cleaning and immune functions. The overall results reinforce the possible link between the fissura magna and the functioning of the glymphatic system. [ABSTRACT FROM AUTHOR]

The nervous system is divided topographically into two parts: the central nervous system and the peripheral nervous system. From a functional perspective, however, the two systems are intimately connected and function in an integrated and coordinated manner. The central nervous system comprises the brain and spinal cord, while the peripheral nervous system is made up of the cranial and peripheral nerves and associated neurological structures. This article presents a broad and general overview of the structure and organization of the nervous system emphasizing several important functional features. [ABSTRACT FROM AUTHOR]

Background: The significant role of embryonic cerebrospinal fluid (eCSF) in the initial stages of brain development has been thoroughly studied. This fluid contains crucial molecules for proper brain development such as members of the Wnt and FGF families, apolipoproteins, and retinol binding protein. Nevertheless, the source of these molecules remains uncertain since they are present before the formation of the choroid plexus, which is conventionally known as the primary producer of cerebrospinal fluid. The subcommissural organ (SCO) is a highly conserved gland located in the diencephalon and is one of the earliest differentiating brain structures. The SCO secretes molecules into the eCSF, prior to the differentiation of the choroid plexus, playing a pivotal role in the homeostasis and dynamics of this fluid. One of the key molecules secreted by the SCO is SCO-spondin, a protein involved in maintenance of the normal ventricle size, straight spinal axis, neurogenesis, and axonal guidance. Furthermore, SCO secretes transthyretin and basic fibroblast growth factor 2, while other identified molecules in the eCSF could potentially be secreted by the SCO. Additionally, various transcription factors have been identified in the SCO. However, the precise mechanisms involved in the early SCO development are not fully understood. Results: To uncover key molecular players and signaling pathways involved in the role of the SCO during brain development, we conducted a transcriptomic analysis comparing the embryonic chick SCO at HH23 and HH30 stages (4 and 7 days respectively). Additionally, a public transcriptomic data from HH30 entire chick brain was used to compare expression levels between SCO and whole brain transcriptome. These analyses revealed that, at both stages, the SCO differentially expresses several members of bone morphogenic proteins, Wnt and fibroblast growth factors families, diverse proteins involved in axonal guidance, neurogenic and differentiative molecules, cell receptors and transcription factors. The secretory pathway is particularly upregulated at stage HH30 while the proliferative pathway is increased at stage HH23. Conclusion: The results suggest that the SCO has the capacity to secrete several morphogenic molecules to the eCSF prior to the development of other structures, such as the choroid plexus. [ABSTRACT FROM AUTHOR]

Background: Previous studies have suggested that the habenula (Hb) may be involved in the mechanism of obsessive-compulsive disorder (OCD). However, the specific role of Hb in OCD remains unclear. This study aimed to explore the structural and functional abnormalities of Hb in OCD and their relationship with the clinical symptoms. Methods: Eighty patients with OCD and 85 healthy controls (HCs) were recruited as the primary dataset. The grey matter volume, resting-state functional connectivity (FC), and effective connectivity (EC) of the Hb were calculated and compared between OCD group and HCs. An independent replication dataset was used to verify the stability and robustness of the results. Results: Patients with OCD exhibited smaller Hb volume and increased FC of right Hb-left hippocampus than HCs. Dynamic causal model revealed an increased EC from left hippocampus to right Hb and a less inhibitory causal influence from the right Hb to left hippocampus in the OCD group compared to HCs. Similar results were found in the replication dataset. Conclusions: This study suggested that abnormal structure of Hb and hippocampus-Hb connectivity may contribute to the pathological basis of OCD. [ABSTRACT FROM AUTHOR]

The feedback regulatory effects of estrogen (E2) and androgen (T) on the gonadotropin-releasing hormone (GnRH) and gonadotropin (GtH) within the brain–pituitary–gonad (BPG) axis in eels with undeveloped ovaries were investigated through in vivo studies. However, the regulatory role of the BPG axis only became apparent during ovary development in the migratory stage. To further elucidate the direct feedback regulation of the BPG axis, female Anguilla japonica underwent artificial induction of vitellogenesis, and the regulation of BPG axis tissues by GtH (human chorionic gonadotropin, hCG), E2, and T was explored through in vitro exposure. The mRNA expression levels of GnRH (mGnRH), GtH (fshb and lhb), and steroid biosynthesis enzymes (cyp11a1, hsd3b, cyp17a1, and cyp17a2) in the diencephalon, pituitary, and ovary, respectively, were determined. The results showed that the expression level of mGnRH in the diencephalon was significantly downregulated by 0.1 IU/mL hCG but upregulated by both 1 nM E2 and higher concentrations of T, suggesting a direct positive feedback regulation of E2 on mGnRH. In the pituitary, the expression levels of fshb and lhb were upregulated by E2, while fshb was suppressed by T. In the ovaries, the expression of cyp11a1 and hsd3b was upregulated by 1 nM E2, whereas T exposure resulted in an opposite effect. Cyp17a1 mRNA levels did not differ significantly with E2 treatment but were upregulated by 1 nM T. These findings suggest that low concentrations of E2 exhibited positive feedback regulation on all three levels (diencephalon, pituitary, and ovary) of the BPG axis, while T showed weaker and differential feedback regulation in BPG axis tissues. Overall, this study's results revealed the direct feedback regulation of hCG, E2, and T on the BPG axis in eels, a phylogenetic base of teleosts. [ABSTRACT FROM AUTHOR]

The impact of ethanol on the fetus is a significant concern as an estimated 2–5% of live births may be affected by prenatal alcohol exposure. This exposure can lead to various functional and structural abnormalities in the cerebral cortex, basal ganglia, diencephalon, and cerebellum, resulting in region-specific symptoms. The deficits relate to the motor and cognitive domains, affecting, in particular, general intelligence, attention, executive functions, language, memory, visual perception, and social skills—collectively called the fetal alcohol spectrum disorder (FASD). Recent studies suggest that damage to the developing cerebellum (in form of alcohol exposure) can impair the cortical targets of the cerebello-thalamo-cortical tract. This malfunction in the cerebello-cerebral loop optimization may be due to disruptions in the formation of the foundational elements of the internal model within the developing cerebellum. Alcohol exposure targets multiple nodes in the reciprocal loops between the cerebellum and cerebral cortex. Here, we examine the possibility that prenatal alcohol exposure damages the developing cerebellum and disrupts the connectivity within the cerebello-cerebral neuronal circuits, exacerbating FASD-related cortical dysfunctions. We propose that malfunctions between cerebellar internal model (critically involved in predictions) and cerebral regions contribute to the deficits observed in FASD. Given the major role of the cerebellum in motor, cognitive, and affective functions, we suggest that therapies should target these malfunctions to mitigate the burden of FASD. We discuss the concept of therapies oriented towards malfunctioning cerebello-cerebral loops (TOMCCLs), emphasizing anti-inflammatory strategies and treatments aimed at modulating cerebellar myelination to restore optimal and predictive cerebello-cerebral functions. [ABSTRACT FROM AUTHOR]

Objective To focus on the efficacy at variable frequency stimulation (VFS) after deep brain stimulation (DBS) for the treatment of axial symptoms in Parkinson's disease (PD). Methods Clinical data of 12 patients with PD who underwent bilateral DBS followed by VFS more than one year from January 2018 to June 2022 at Tianjin Huanhu Hospital, Tianjin University were retrospectively analyzed. Axial symptoms were assessed using Unified Parkinson's Disease Rating Scale (UPDRS)-gait posture, Timed Up and Go Test (TUGT) time and the occurrence of freezing of gait (FOG), The Freezing of Gait - Questionnaire (FOG - Q), and Berg Balance Scale (BBS). The above indicators were recorded one week before DBS surgery and in the drug "off" period (baseline), at the end of high frequency stimulation (the end of HFS), at one month follow-up of VFS (short-term VFS), and at one year or more follow-up of VFS (long-term VFS). Results Compared with baseline, BBS scores increased at the end of HFS (t = - 2.845, P = 0.008); UPDRS-gait posture (t = 12.703, P = 0.000; t = 11.737, P = 0.000), TUGT time (t = 8.923, P = 0.000; t = 8.025, P = 0.000) and the occurrence of FOG (t = 4.448, P = 0.000; t = 4.181, P = 0.000), and FOG Q scores (t = 9.186, P = 0.000; t = 8.186, P = 0.000) decreased, while the BBS scores increased (t = - 7.686, P = 0.000; t = - 6.106, P = 0.000) in both short-term VFS and long-term VFS. Compared with the end of HFS, UPDRS-gait posture (t = 11.583, P = 0.000; t = 10.618, P = 0.000), TUGT time (t = 6.922, P = 0.000; t = 6.022, P = 0.000) and the occurrence of FOG (t = 3.612, P = 0.001; t = 3.344, P = 0.002), and FOG-Q scores (t = 7.915, P = 0.000; t = 6.915, P = 0.000) decreased, while the BBS scores increased (t = - 4.842, P = 0.000; t = - 3.262, P = 0.003) in short-term VFS and long-term VFS. Conclusions For PD patients with HFS but poor axial symptoms efficacy after DBS, the use of VFS significantly improves multifaceted axial symptoms with reliable long-term efficacy. [ABSTRACT FROM AUTHOR]

Objective To explore the correlation between functional connectivity (FC) in the brains of Parkinson's disease (PD) patients with depression and the improvement rate of depression after subthalamic nucleus deep brain stimulation (STN-DBS). Methods This study included 38 PD patients (25 with depression and 13 without depression) who underwent STN -DBS at The First Affiliated Hospital of University of Science and Technology of China from September 2019 to April 2020. All participants underwent resting-state fMRI. The severity of depression was assessed using Hamilton Depression Rating Scale-17 Items (HAMD-17) before and 2 years after the surgery, and the improvement rate of depression was calculated. Spearman rank correlation analysis was used to investigate the relationship between FC and the improvement rate of depression in PD patients with depression. Results There were 34 different FC between PD patients with and without depression compared to control group (P = 0.000, for all). Among patients with PD, those with depression showed 4 distinct FC compared to those without depression, including left precuneus-right supplementary motor area (t = 6.028, P = 0.000), right insula-right lateral orbital gyrus (t = 5.525, P = 0.000), left paracentral lobule-left precuneus (t = 5.545, P = 0.000), and right paracentral lobule - left precuneus (t = 5.578, P = 0.000). Spearman rank correlation analysis revealed a negative correlation between the zFC values of right precuneus-right insula (rs = - 0.544, P = 0.009) and left temporal pole-left insula (rs = - 0.765, P = 0.010) and the improvement rate of depression in PD patients with depression. Conclusions The FC of right precuneus-right insula and left temporal pole-left insula in PD patients with depression is negatively associated with the improvement rate of depression. [ABSTRACT FROM AUTHOR]

Autonomic nerve dysfunction is a common non-motor symptom of Parkinson's disease (PD). It has a high incidence and involves multiple organ system disorders with various manifestations, seriously affecting the quality of life. Autonomic nerve dysfunction can be a major symptom of advanced PD and a major cause of disability. Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for advanced PD, and its improvement of motor symptoms in PD patients has been widely recognized. However, the effect of STN - DBS on the symptoms of autonomic nerve dysfunction in PD patients is still unclear. Here, the efficacy of STN - DBS on PD autonomic nerve dysfunction is briefly reviewed. Therefore, we should pay more attention to the symptoms of autonomic nerve dysfunction in PD patients, and conduct preoperative evaluation of DBS in PD patients, so as to comprehensively consider the postoperative efficacy, target selection, stimulus parameter setting, drug adjustment, develop an individualized treatment plan. [ABSTRACT FROM AUTHOR]

The purpose of this review extends beyond the traditional triune brain model, aiming to elucidate the evolutionary aspects of alpha rhythms in vertebrates. The forebrain, comprising the telencephalon (pallium) and diencephalon (thalamus, hypothalamus), is a common feature in the brains of all vertebrates. In mammals, evolution has prioritized the development of the forebrain, especially the neocortex, over the midbrain (mesencephalon) optic tectum, which serves as the prototype for the visual brain. This evolution enables mammals to process visual information in the retina-thalamus (lateral geniculate nucleus)-occipital cortex pathway. The origin of posterior-dominant alpha rhythms observed in mammals in quiet and dark environments is not solely attributed to cholinergic pontine nuclei cells functioning as a 10 Hz pacemaker in the brainstem. It also involves the ability of the neocortex's cortical layers to generate traveling waves of alpha rhythms with waxing and waning characteristics. The utilization of alpha rhythms might have facilitated the shift of attention from external visual inputs to internal cognitive processes as an adaptation to thrive in dark environments. The evolution of alpha rhythms might trace back to the dinosaur era, suggesting that enhanced cortical connectivity linked to alpha bands could have facilitated the development of nocturnal awakening in the ancestors of mammals. In fishes, reptiles, and birds, the pallium lacks a cortical layer. However, there is a lack of research clearly observing dominant alpha rhythms in the pallium or organized nuclear structures in fishes, reptiles, or birds. Through convergent evolution, the pallium of birds, which exhibits cortex-like fiber architecture, has not only acquired advanced cognitive and motor abilities but also the capability to generate low-frequency oscillations (4-25 Hz) resembling alpha rhythms. This suggests that the origins of alpha rhythms might lie in the pallium of a common ancestor of birds and mammals. [ABSTRACT FROM AUTHOR]

The article presents a case study of a patient with Parkinson's disease who experienced deterioration in writing ability, known as micrographia, following subthalamic nucleus deep brain stimulation (STN-DBS) surgery, despite improvement in other motor symptoms. The study highlights the dynamic association between STN-DBS activation and micrographia, suggesting potential mechanisms beyond traditional hypokinetic effects, and discusses the anatomical and functional considerations of STN-DBS.

The cerebellum is involved in many motor, autonomic and cognitive functions, and new tasks that have a cerebellar contribution are discovered on a regular basis. Simultaneously, our insight into the functional compartmentalization of the cerebellum has markedly improved. Additionally, studies on cerebellar output pathways have seen a renaissance due to the development of viral tracing techniques. To create an overview of the current state of our understanding of cerebellar efferents, we undertook a systematic review of all studies on monosynaptic projections from the cerebellum to the brainstem and the diencephalon in mammals. This revealed that important projections from the cerebellum, to the motor nuclei, cerebral cortex, and basal ganglia, are predominantly di- or polysynaptic, rather than monosynaptic. Strikingly, most target areas receive cerebellar input from all three cerebellar nuclei, showing a convergence of cerebellar information at the output level. Overall, there appeared to be a large level of agreement between studies on different species as well as on the use of different types of neural tracers, making the emerging picture of the cerebellar output areas a solid one. Finally, we discuss how this cerebellar output network is affected by a range of diseases and syndromes, with also non-cerebellar diseases having impact on cerebellar output areas. [ABSTRACT FROM AUTHOR]

Background: Subthalamic nucleus (STN) and globus pallidus interna (GPi) are two main structures primarily targeted by deep brain stimulation (DBS) to treat advanced Parkinson's disease (PD). A subset of cases with unsatisfactory outcomes may benefit from rescue DBS surgery targeting another structure, while these patients' characteristics have not been well described and this phenomenon has not been well reviewed. Methods: This monocentric retrospective study included patients with PD, who underwent rescue STN DBS following an unsatisfactory outcome of the initial bilateral GPi DBS in a retrospective manner. A short review of the current literature was conducted to report the clinical outcome of rescue DBS surgeries. Results: Eight patients were identified, and six of them were included in this study. The rescue STN DBS was performed 19.8 months after the initial GPi DBS. After 8.8 months from the rescue STN DBS, patients showed a significant off-medication improvement by 29.2% in motor symptoms compared to initial GPi DBS. Non-motor symptoms and the health-related quality of life were also significantly improved. Conclusion: Our findings suggest that the rescue STN DBS may improve off-medication motor and non-motor symptoms and quality of life in patients with failure of initial GPi DBS. The short review of the current literature showed that the target switching from GPi to STN was mainly due to poor initial outcomes and was performed by target substitution, whereas the switching from STN to GPi was mainly due to a gradual waning of benefits, long-term axial symptoms, dyskinesia, and dystonia and was performed by target addition. [ABSTRACT FROM AUTHOR]

Astrocytes are the largest glial population in the mammalian brain. However, we have a minimal understanding of astrocyte development, especially fate specification in different regions of the brain. Through lineage tracing of the progenitors of the third ventricle (3V) wall via in-utero electroporation in the embryonic mouse brain, we show the fate specification and migration pattern of astrocytes derived from radial glia along the 3V wall. Unexpectedly, radial glia located in different regions along the 3V wall of the diencephalon produce distinct cell types: radial glia in the upper region produce astrocytes and those in the lower region produce neurons in the diencephalon. With genetic fate mapping analysis, we reveal that the first population of astrocytes appears along the zona incerta in the diencephalon. Astrogenesis occurs at an early time point in the dorsal region relative to that in the ventral region of the developing diencephalon. With transcriptomic analysis of the region-specific 3V wall and lateral ventricle (LV) wall, we identified cohorts of differentially-expressed genes in the dorsal 3V wall compared to the ventral 3V wall and LV wall that may regulate astrogenesis in the dorsal diencephalon. Together, these results demonstrate that the generation of astrocytes shows a spatiotemporal pattern in the developing mouse diencephalon. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To assess the effect of bilateral subthalamic nucleus deep brain stimulation (B/L STN DBS) on the progression of dyskinesia and the levodopa equivalent daily dose (LEDD) in advanced Parkinson's disease (APD) patients 6 months postoperatively. METHODS: Seventeen APD patients aged 21-80 years with the minimum modified Hoen & Yahr score of 2 while off medication and poor motor function underwent B/L STN DBS from January 2021 to December 2021. They were assessed preoperatively and 6 months postoperatively using the Unified dyskinesia rating scale (UDysRS) and Unified Parkinson's Disease Rating Scale Part IV (UPDRS IV) for dyskinesia and LEDD dosage. RESULTS: Significant improvement was observed postoperatively in both UDysRS (pre-op 66.53 ± 24.59, post-op 30.88 ± 12.01; P = 0.000) and UPDRS IV (pre-op 9.24 ± 1.75, post-op 5.76 ± 1.39; P = 0.000) scores. The overall clinical improvement using UDysRS was 52.23 ± 16.23%. Each subscale of UDysRS showed significant improvement postoperatively: ON dyskinesia (pre-op 21 ± 7.7, post-op 13.76 ± 5.79; P < 0.05); OFF dystonia (pre-op 8.53 ± 3.26, post-op 4.94 ± 2.70; P < 0.05); impairment (face, pre-op 2.47 ± 2.52, post-op 0.29 ± 0.98, P < 0.05; neck and trunk, pre-op 6.29 ± 4.55, post-op 0.59 ± 0.87, P < 0.05; arms, pre-op 13.06 ± 5.86, post-op 5.76 ± 3.7, P < 0.05; and legs, pre-op 7.18 ± 5.12, post-op 1.29 ± 1.57, P < 0.05); and disability (pre-op 8 ± 3.46, post-op 4.24 ± 2.25; P < 0.05), suggesting high clinical significance. LEDD (pre-op 673.41 ± 212.69 mg, post-op 386.82 ± 133.01 mg; P = 0.000) showed significant reduction in dosage 6 months postoperatively. LEDD reduction and dyskinesia improvement showed mild-to-moderate positive correlation (r = 0.404). CONCLUSION: B/L STN DBS helps in improving dyskinesia by reducing LEDD in APD patients. [ABSTRACT FROM AUTHOR]

The diencephalon, an integral component of the forebrain, governs a spectrum of crucial functions, ranging from sensory processing to emotional regulation. Yet, unraveling its unique development, intricate connectivity, and its role in neurodevelopmental disorders has long been hampered by the scarcity of human brain tissue and ethical constraints. Recent advancements in stem cell technology, particularly the emergence of brain organoids, have heralded a new era in neuroscience research. Although most brain organoid methodologies have hitherto concentrated on directing stem cells toward telencephalic fates, novel techniques now permit the generation of region-specific brain organoids that faithfully replicate precise diencephalic identities. These models mirror the complexity of the human diencephalon, providing unprecedented opportunities for investigating diencephalic development, functionality, connectivity, and pathophysiology in vitro. This review summarizes the development, function, and connectivity of diencephalic structures and touches upon developmental brain disorders linked to diencephalic abnormalities. Furthermore, it presents current diencephalic organoid models and their applications in unraveling the intricacies of diencephalic development, function, and pathology in humans. Lastly, it highlights thalamocortical assembloid models, adept at capturing humanspecific aspects of thalamocortical connections, along with their relevance in neurodevelopmental disorders. [ABSTRACT FROM AUTHOR]

Abstract Background Autism spectrum disorder (ASD) is a neurobehavioural disorder, characterized by abnormal affiliative and socio-emotional responses which are generally regulated by certain neuropeptides in the hypothalamus (an anatomic component of the ventral diencephalon (VD)). The use of volumetric MRI for studying VD volume change could provide a novel approach for identification of structural brain changes in ASD; this could assist in understanding the pathophysiology of ASD and would reflect on treatment strategies. The aim of the current work was to investigate the role of MRI volumetric analysis of the ventral diencephalon in young children diagnosed with autism spectrum disorder. Methods Fifty children diagnosed with ASD underwent volumetric brain analysis, on a fully automated MRI brain volumetry system (volBrain), with voxel-based morphometry of various segmental structures of the brain including the VD, using vol2Brain 1.0 pipeline software analysis suite. Results There were 48 out of 50 children who demonstrated abnormal VD volume which was found below the normal limits compared with reference standard normalized volume. All cases were normocephalic demonstrating normal intra-cranial cavity volumes. Forty out of fifty cases showed increased total volume of grey matter, and eighteen out of fifty cases showed increased total volume of white matter. Regarding the amygdala and hippocampus, there were only two cases (4.0%) which showed slightly increased relative volume of the total amygdala, and two other cases (4.0%) demonstrated increased relative volume of the total hippocampus. Comparison between the autistic patients and normal references revealed a significant difference regarding the VD volume and total volume of grey matter, whereas no significant differences were found regarding the white matter amygdala and hippocampus. Conclusions Based on the consistent significant volume decrease in the ventral diencephalon in patients with childhood autism, this study concluded that volumetric MRI analysis could be useful for diagnosis of childhood spectrum disorder and could be utilized as a reliable screening method in the clinically vague cases. Further study with a larger sample size including more age groups is recommended for more validation of the results.

The diencephalon, an integral component of the forebrain, governs a spectrum of crucial functions, ranging from sensory processing to emotional regulation. Yet, unraveling its unique development, intricate connectivity, and its role in neurodevelopmental disorders has long been hampered by the scarcity of human brain tissue and ethical constraints. Recent advancements in stem cell technology, particularly the emergence of brain organoids, have heralded a new era in neuroscience research. Although most brain organoid methodologies have hitherto concentrated on directing stem cells toward telencephalic fates, novel techniques now permit the generation of region-specific brain organoids that faithfully replicate precise diencephalic identities. These models mirror the complexity of the human diencephalon, providing unprecedented opportunities for investigating diencephalic development, functionality, connectivity, and pathophysiology in vitro. This review summarizes the development, function, and connectivity of diencephalic structures and touches upon developmental brain disorders linked to diencephalic abnormalities. Furthermore, it presents current diencephalic organoid models and their applications in unraveling the intricacies of diencephalic development, function, and pathology in humans. Lastly, it highlights thalamocortical assembloid models, adept at capturing human-specific aspects of thalamocortical connections, along with their relevance in neurodevelopmental disorders.

Reproduction is subtlety regulated by the hypothalamic-pituitary-gonad (HPG) axis in vertebrates. Pituitary gland is the center of the HPG axis, while pituitary gonadotropins follicle stimulating hormone (FSH) and luteinizing hormone (LH) were identified the key elements of the HPG axis in teleost and mammal. Morphology, cell lines, and gonadotropins cell localization of female turbot and mouse pituitary were determined at mature stage to illustrate the anatomical difference and cell characteristics in this study. Results show that turbot pituitary is chicken heart-shaped, dorsoventral, located on the ventral surface of the diencephalon. The mouse pituitary is oval, located in the pituitary fossa of the sella turcica at the skull base. Two well-distinguished areas adenohypophysis (AH) and neurohypophysis (NH) in pituitary were identified in turbot and mouse. Turbot AH comprised the rostral pars distalis (RPD), proximal pars distalis (PPD), and pars intermedia (PI). NH was not pronounced and with finger-like protrusions into PPD. However, mouse AH only comprised the pars distalis (PD) and PI. NH distribution was semicircular. Three main types of cells (acidophilic, basophilic, and chromophobic cells) were distributed in the mouse PD region, whereas appeared in the turbot PPD, RPD, and PI. Moreover, the percentage of mouse chromophobic and basophilic cells was higher and lower than that of turbot, respectively. The diameter of the aforementioned three cells in the mouse was significantly higher than turbot. fshβ- and lhβ-immunoreactive signals were identified in turbot-distinct pituitary cells that primarily occupied the peripheral and central regions of AH. However, mouse fsh- and lh-immunoreactive cells were expressed in the same cells and present in the PD. These results demonstrate the significantly difference of pituitary morphology, cell lines and gonadotropins (fshβ and lhβ) location in female turbot and mouse. These differences help for fully understand the evolution and endocrinological functions of pituitary. [ABSTRACT FROM AUTHOR]

Background: Autism spectrum disorder (ASD) is a neurobehavioural disorder, characterized by abnormal affiliative and socio-emotional responses which are generally regulated by certain neuropeptides in the hypothalamus (an anatomic component of the ventral diencephalon (VD)). The use of volumetric MRI for studying VD volume change could provide a novel approach for identification of structural brain changes in ASD; this could assist in understanding the pathophysiology of ASD and would reflect on treatment strategies. The aim of the current work was to investigate the role of MRI volumetric analysis of the ventral diencephalon in young children diagnosed with autism spectrum disorder. Methods: Fifty children diagnosed with ASD underwent volumetric brain analysis, on a fully automated MRI brain volumetry system (volBrain), with voxel-based morphometry of various segmental structures of the brain including the VD, using vol2Brain 1.0 pipeline software analysis suite. Results: There were 48 out of 50 children who demonstrated abnormal VD volume which was found below the normal limits compared with reference standard normalized volume. All cases were normocephalic demonstrating normal intra-cranial cavity volumes. Forty out of fifty cases showed increased total volume of grey matter, and eighteen out of fifty cases showed increased total volume of white matter. Regarding the amygdala and hippocampus, there were only two cases (4.0%) which showed slightly increased relative volume of the total amygdala, and two other cases (4.0%) demonstrated increased relative volume of the total hippocampus. Comparison between the autistic patients and normal references revealed a significant difference regarding the VD volume and total volume of grey matter, whereas no significant differences were found regarding the white matter amygdala and hippocampus. Conclusions: Based on the consistent significant volume decrease in the ventral diencephalon in patients with childhood autism, this study concluded that volumetric MRI analysis could be useful for diagnosis of childhood spectrum disorder and could be utilized as a reliable screening method in the clinically vague cases. Further study with a larger sample size including more age groups is recommended for more validation of the results. [ABSTRACT FROM AUTHOR]

Objective: The spatiotemporal gait changes in advanced Parkinson's disease (PD) remain a treatment challenge and have variable responses to L-dopa and subthalamic deep brain stimulation (STN-DBS). The purpose of this study was to determine whether low-frequency STN-DBS (LFS; 60Hz) elicits a differential response to high-frequency STN-DBS (HFS; 180Hz) in spatiotemporal gait kinematics. Methods: Advanced PD subjects with chronic STN-DBS were evaluated in both theOFF andONmedication states with LFS and HFS stimulation. Randomization of electrode contact pairs and frequency conditions was conducted. Instrumented Stand and Walk assessments were carried out for every stimulation/medication condition. LM-ANOVA was employed for analysis. Results: Twenty-two PD subjects participated in the study, with a mean age (SD) of 63.9 years. Significant interactions between frequency (both LFS and HFS) and electrode contact pairs (particularly ventrally located contacts) were observed for both spatial (foot elevation, toe-off angle, stride length) and temporal (foot speed, stance, single limb support (SLS) and foot swing) gait parameters. A synergistic effect was also demonstrated with L-dopa and both HFS and LFS for right SLS, left stance, left foot swing, right toe-off angle, and left arm range of motion. HFS produced significant improvement in trunk and lumbar range of motion compared to LFS. Conclusion: The study provides evidence of synergismof L-dopa and STN-DBS on lower limb spatial and temporal measures in advanced PD. HFS and LFS STN-DBS produced equivalent effects among all other tested lower limb gait features. HFS produced significant trunk and lumbar kinematic improvements. [ABSTRACT FROM AUTHOR]

Neurological involvement in Behçet's syndrome arises predominately through an inflammatory meningoencephalitis characterised by perivenular inflammation due to activation of Th-17 immunological pathways. The brainstem is involved in 50% of cases, the diencephalon and other areas of the brain in 30%, and the spinal cord in 10%. Movement disorders and epilepsy may occur. Psychiatric syndromes may arise with brain and brainstem involvement, and cognitive disorders relate to the brain disease, to circulating inflammatory factors, and to fatigue and despondency. Eighty per cent of cases begin with a relapsing disease course, of whom 70% have only one attack, and 30% have a progressive disease course either from onset or following an initially relapsing course. Venous thrombosis leading to intracranial hypertension and cerebral venous infarction is less common and caused by inflammation in affected veins and a circulating prothrombotic state. Arterial involvement is rare and relates to an arteritis affecting large-sized and medium-sized vessels within the brain leading to infarction, subarachnoid and parenchymal haemorrhage, aneurysm formation and arterial dissection. There is a newly recognised disorder of cerebral cortical hypoperfusion. Cranial neuropathy, peripheral neuropathy and myositis are rare. There has been significant progress in understanding the pathophysiology and treatment of the systemic disease, leading to improved outcomes, but there has been no randomised trial of treatment in the neurological disorder. [ABSTRACT FROM AUTHOR]

Some fish in tropical and subtropical waters exhibit moon-related rhythmicity in their reproduction and migration. We investigated the involvement of the subtypes of cryptochrome (mgCry) in moon-related rhythmicity of the Malabar grouper Epinephelus malabaricus, which spawns around the new moon period. Under natural photoperiodic conditions, the levels of mgCry1 and mgCry2 showed daily variation with peaks at 11:00 and 19:00, respectively, in the diencephalon (including the pituitary), regardless of the moon phase. The weekly changes in mgCry2, but not mgCry1, were moon-dependent, with higher levels around the new moon. When fish were reared under natural moonlight, mgCry2 in the pituitary was higher at 15:00 and 11:00 during the new moon period than the full moon period. Rearing fish under moonlight-exposed or moonlight-blocked conditions resulted in increases in mgCry genes in the pituitary during the night at full moon, suggesting that the pituitary is a target organ of the moonlight-dependent clock system. These findings indicate that mgCry genes in the brain of the Malabar grouper exhibits moon dependency, with changes according to the duration of darkness at night. We conclude that weekly changes in Cry genes in the brain play a role in entraining moon-dependent events in the Malabar grouper. [ABSTRACT FROM AUTHOR]

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Background: It is well known that motor features of Parkinson’s disease (PD) commonly begin on one side of the body and extend to the other side with disease progression. The onset side generally remains more severely affected over the course of the disease. However, the pathophysiology underlying the asymmetry of motor manifestations remains unclear. The purpose of the present study is to examine whether alterations in neuronal activity in the subthalamic nucleus (STN) associate with PD severity. Methods: Microelectrode recording was performed in the STN during targeting for 30 patients in the treatment of deep brain stimulation. The mean spontaneous firing rate (MSFR), power density spectral analysis, and correlations were calculated. Characteristics of subthalamic oscillatory activity were compared between two hemispheres. UPDRS III scores during “Off” and “On” states were obtained for the body side of initial symptoms (BSIS) and the body side of extended symptoms (BSES). Results: There were significant differences of MSFR (41.3 ± 11.0 Hz vs 35.2 ± 10.0 Hz) and percentage of ß frequency oscillatory neurons (51.3% vs 34.9%) between BSIS and BSES. The percentage of ß frequency oscillatory neurons correlated with the bradykinesia/rigidity scores for both sides (p < 0.05). In contrast, the percentage of tremor frequency oscillatory neurons was significantly higher in the BSES than that in the BSIS. In particular, these neurons only correlated with the tremor scores of the BSES (p < 0.05). Conclusion: The results suggest that increased neuronal firing rate and ß frequency oscillatory neurons in the STN are associated with contralateral side motor severity and its progression. Tremor frequency oscillatory neurons are less observed in the STN of the BSIS suggesting that ß oscillatory activity dominates and tremor frequency oscillatory activity reciprocally declines. [ABSTRACT FROM AUTHOR]

This study explored changes in brain serotonin content and activity together with hypothalamic neuropeptide mRNA abundance around feeding time in rainbow trout, as well as the effect of one-day fasting. Groups of trout fed at two (ZT2) and six (ZT6) hours after lights on were sampled from 90 minutes before to 240 minutes after feeding, while additional groups of non-fed trout were also included in the study. Changes in brain amine and metabolite contents were measured in hindbrain, diencephalon and telencephalon, while in the diencephalon the mRNA abundance of tryptophan hydroxylase (tph1, tph2), serotonin receptors (5htr1a, 5htr1b and 5htr2c) and several neuropeptides (npy, agrp1, cartpt, pomca1, crfb) involved in the control of food intake were also assessed. The results showed changes in the hypothalamic neuropeptides that were consistent with the expected role for each in the regulation of food intake in rainbow trout. Serotonergic activity increased rapidly at the time of food intake in the diencephalon and hindbrain and remained high for much of the postprandial period. This increase in serotonin abundance was concomitant with elevated levels of pomca1 mRNA in the diencephalon, suggesting that serotonin might act on brain neuropeptides to promote a satiety profile. Furthermore, serotonin synthesis and neuronal activity appear to increase already before the time of feeding, suggesting additional functions for this amine before and during food intake. Exploration of serotonin receptors in the diencephalon revealed only small changes for gene expression of 5htr1b and 5htr2c receptors during the postprandial phase. Therefore, the results suggest that serotonin may play a relevant role in the regulation of feeding behavior in rainbow trout during periprandial time, but a better understanding of its interaction with brain centers involved in receiving and processing food-related signals is still needed. [ABSTRACT FROM AUTHOR]

To explore the physical activity of people with Parkinson's disease (PD) with subthalamic nucleus deep brain stimulation (STN-DBS) and investigate factors associated with physical activity. Twenty-four participants who had STN-DBS for one or more years were recruited. Eligibility criteria included Hoehn and Yahr stage ≤ 4, continuation of STN-DBS, living at home and able to provide informed consent. Physical activity was measured using the self-report physical activity scale for the elderly (PASE). Motor and non-factors that influence physical activity in PD, such as gait disturbance and mood, were recorded using clinical measures. Participants had long-standing PD of moderate severity, mean Hoehn and Yahr 2.3, and mild to moderate functional disability, MDS-UPDRS M-EDL mean 16.2. PASE scores were significantly lower compared to norms for adults ≤ 70 years (115.2 versus 143, p= 0.045). There was a significant negative correlation between PASE scores and falls history, fatigue, fear of falling (FOF) and quality of life (p < 0.05). This study provides further evidence that physical activity levels in PD with STN-DBS remain low compared to PASE norms for older adults. Future research investigating interventions to improve factors associated with low physical activity levels should be considered. Despite the benefits of deep brain stimulation (DBS) on motor function and activities of daily living, physical activity levels remain low in people with Parkinson's disease (PD) with subthalamic nucleus (STN)-DBS compared to norms for older adults. A history of falls, greater fear of falling (FOF) and higher levels of fatigue are associated with lower levels of physical activity in people with PD with STN-DBS. When planning rehabilitation interventions consideration should be given to strategies that promote and support regular physical activity for people with PD with STN-DBS. Rehabilitation clinicians should consider using falls prevention programmes and include strategies to decrease FOF for people with PD with STN-DBS. Consideration should be given to the presence of fatigue when planning the rehabilitation programme for the person with PD with STN-DBS. [ABSTRACT FROM AUTHOR]

Basal ganglia play a central role in regulating behavior, but the organization of their outputs to other brain areas is incompletely understood. We investigate the largest output nucleus, the substantia nigra pars reticulata (SNr), and delineate the organization and physiology of its projection populations in mice. Using genetically targeted viral tracing and whole-brain anatomical analysis, we identify over 40 SNr targets that encompass a roughly 50-fold range of axonal densities. Retrograde tracing from the volumetrically largest targets indicates that the SNr contains segregated subpopulations that differentially project to functionally distinct brain stem regions. These subpopulations are electrophysiologically specialized and topographically organized and collateralize to common diencephalon targets, including the motor and intralaminar thalamus as well as the pedunculopontine nucleus and the midbrain reticular formation. These findings establish that SNr signaling is organized as dense, parallel outputs to specific brain stem targets concurrent with extensive collateral branches that encompass the majority of SNr axonal boutons.

Background: Little is known about the brainstem in healthy three-year-old children; yet there is a need for further studies because children at this age are growing and developing rapidly.Objective: To study differences in the brainstem and its cavities in healthy three-year-old children, considering the sex and bilateral asymmetry.Materials and methods: We retrospectively analyzed 120 MRI scans of healthy three-year-old children (60 boys and 60 girls) to study the brainstem features. The following parameters of the brain stem structures were assessed: 1) the length of the pons (mm), 2) the height of the pons (mm), 3) the length of the medulla oblongata (mm), 4) the height of the medulla oblongata at the upper and lower borders (mm), 5) the length and height of the vermis (mm), 6) the width of the cerebellum (mm), 7) the length, width, height of the cerebellar hemispheres (mm), 8) the length and height of the third ventricle, 9) the length of the cerebral aqueduct (mm), 10) the length and height of the fourth ventricle (mm). We assessed the compliance of quantitative parameters with the normal distribution according to the Kolmogorov-Smirnov criterion. We used Microsoft Excel 2016 tables to accumulate, correct and systemize the raw data. Statistica 10.0 software (StatSoft. Inc., USA) along with the corresponding statistical method provided the digital data. The differences were considered significant at P < .05.Results: We aimed to study sex-related differences in the basic sizes of the brainstem. The length and height of the pons, the length of the third and the fourth ventricles, and the size of the cerebellar hemispheres were greater in boys. We found a bilateral asymmetry in cerebellar hemispheres (length, width, and height).Conclusions: The changes in the complex brainstem of three-year-old children are sex-dependent and consist in active transformations of its structures.

This document is a correction notice for an article titled "A Systematic Review of Direct Outputs from the Cerebellum to the Brainstem and Diencephalon in Mammals" published in the journal Cerebellum. The correction states that there was a mistake in the original article, specifically in Table 1 where a reference number was incorrect. The correction provides the correct reference number and mentions that the table has been simplified. The original article has been corrected and the publisher, Springer Nature, remains neutral in terms of jurisdictional claims and affiliations. The authors of the article are Manuele Novello, Laurens W. J. Bosman, and Chris I. De Zeeuw. [Extracted from the article]

Introduction: Although the subthalamic nucleus (STN) has proven to be a safe and effective target for deep brain stimulation (DBS) in the treatment of primary dystonia, the rates of individual improvement vary considerably. On the premise of selecting appropriate patients, the location of the stimulation contacts in the dorsolateral sensorimotor area of the STN may be an important factor affecting therapeutic effects, but the optimal location remains unclear. This study aimed to define an optimal location using the medial subthalamic nucleus border as an anatomical reference and to explore the influence of the location of active contacts on outcomes and programming strategies in a series of patients with primary dystonia. Methods: Data from 18 patients who underwent bilateral STN-DBS were retrospectively acquired and analyzed. Patients were assessed preoperatively and postoperatively (1 month, 3 months, 6 months, 1 year, 2 years, and last follow-up after neurostimulator initiation) using the Toronto Western Spasmodic Torticollis Rating Scale (for cervical dystonia) and the Burke-Fahn-Marsden Dystonia Rating Scale (for other types). Optimal parameters and active contact locations were determined during clinical follow-up. The position of the active contacts relative to the medial STN border was determined using postoperative stereotactic MRI. Results: The clinical improvement showed a significant negative correlation with the y-axis position (anterior-posterior; A+, P-). The more posterior the electrode contacts were positioned in the dorsolateral sensorimotor area of the STN, the better the therapeutic effects. Cluster analysis of the improvement rates delineated optimal and sub-optimal groups. The optimal contact coordinates from the optimal group were 2.56 mm lateral, 0.15 mm anterior, and 1.34 mm superior relative to the medial STN border. Conclusion: STN-DBS was effective for primary dystonia, but outcomes were dependent on the active contact location. Bilateral stimulation contacts located behind or adjacent to Bejjani's line were most likely to produce ideal therapeutic effects. These findings may help guide STN-DBS preoperative planning, stimulation programming, and prognosis for optimal therapeutic efficacy in primary dystonia. [ABSTRACT FROM AUTHOR]

The diencephalon is a complex midline structure consisting of the hypothalamus, neurohypophysis, subthalamus, thalamus, epithalamus, and pineal body. Tumors arising from each of these diencephalic components differ significantly in terms of biology and prognosis. The aim of this comprehensive review is to describe the epidemiology, clinical symptoms, imaging, histology, and molecular markers in the context of the 2021 WHO classification of central nervous system neoplasms. We will also discuss the current management of each of these tumors. [ABSTRACT FROM AUTHOR]

Local circuit neurons are present in the thalamus of all vertebrates where they are considered inhibitory. They play an important role in computation and influence the transmission of information from the thalamus to the telencephalon. In mammals, the percentage of local circuit neurons in the dorsal lateral geniculate nucleus remains relatively constant across a variety of species. In contrast, the numbers of local circuit neurons in the ventral division of the medial geniculate body in mammals vary significantly depending on the species examined. To explain these observations, the numbers of local circuit neurons were investigated by reviewing the literature on this subject in these two nuclei in mammals and their respective homologs in sauropsids and by providing additional data on a crocodilian. Local circuit neurons are present in the dorsal geniculate nucleus of sauropsids just as is the case for this nucleus in mammals. However, sauropsids lack local circuits neurons in the auditory thalamic nuclei homologous to the ventral division of the medial geniculate body. A cladistic analysis of these results suggests that differences in the numbers of local circuit neurons in the dorsal lateral geniculate nucleus of amniotes reflect an elaboration of these local circuit neurons as a result of evolution from a common ancestor. In contrast, the numbers of local circuit neurons in the ventral division of the medial geniculate body changed independently in several mammalian lineages. [ABSTRACT FROM AUTHOR]

The retina, as an external extension of the diencephalon, can be directly, noninvasively observed by ocular fundus photography. Therefore, it offers a convenient and feasible mode to study nervous system diseases. Caliber, tortuosity, and fractal dimension, as three commonly used retinal vascular parameters, are not only the reflection of structural changes in the retinal microcirculation but also capture the branching pattern or density changes of the retinal microvascular network. Therefore, it contributes to better reflecting the subclinical pathological changes (e.g., lacunar stroke and small cerebral vascular disease) and predicting the risk of incident stroke and recurrent stroke. [ABSTRACT FROM AUTHOR]

We report neuropsychological and neuropathological findings for a patient (A.B.), who developed memory impairment after a cardiac arrest at age 39. A.B. was a clinical psychologist who, although unable to return to work, was an active participant in our neuropsychological studies for 24 y. He exhibited a moderately severe and circumscribed impairment in the formation of long-term, declarative memory (anterograde amnesia), together with temporally graded retrograde amnesia covering ∼5 y prior to the cardiac arrest. More remote memory for both facts and autobiographical events was intact. His neuropathology was extensive and involved the medial temporal lobe, the diencephalon, cerebral cortex, basal ganglia, and cerebellum. In the hippocampal formation, there was substantial cell loss in the CA1 and CA3 fields, the hilus of the dentate gyrus (with sparing of granule cells), and the entorhinal cortex. There was also cell loss in the CA2 field, but some remnants remained. The amygdala demonstrated substantial neuronal loss, particularly in its deep nuclei. In the thalamus, there was damage and atrophy of the anterior nuclear complex, the mediodorsal nucleus, and the pulvinar. There was also loss of cells in the medial and lateral mammillary nuclei in the hypothalamus. We suggest that the neuropathology resulted from two separate factors: the initial cardiac arrest (and respiratory distress) and the recurrent seizures that followed, which led to additional damage characteristic of temporal lobe epilepsy.