Journal of Neuroscience Methods最新文献

Background: Multiple sclerosis (MS) is a chronic inflammatory autoimmune neurological characterized by muscle weakness, numbness, tingling, vision problems, and difficulty in coordination and balance caused by the damage of myelin content around the nerve fibres. The recent literature is evident that along with their lymphocyte attack prevention mechanism, fingolimod (FNG) can serve as neuroprotective also by ensuring their improved brain availability. Therefore, in this project brain availability of FNG was enhanced by delivering the FNG in the form of nanoparticles.

New methods: Fingolimod-loaded solid lipid nanoparticles (FNG-SLNs) were prepared using the solvent evaporation method and formulation factors (lipid concentration; X1, speed; X2, surfactant concentration; X3) and response were established by factorial design. FNG-SLNs were characterized for particle size, entrapment efficiency and in-vitro drug release. Optimized formulations were characterized for in-vivo efficacy study in ethidium bromide-induced MS rat model.

Result: Obtained data revealed that the particle size and entrapment efficiency of FNG-SLNs optimized formulation was 125.4nm and 79.86% w/w respectively. In-vitro drug release study showed an initial burst release of the FNG up to 32.52% in 30min followed by sustained drug release up to 78.22% in 24h. Furthermore, in-vivo data of FNG-SLNs on ethidium bromide-induced MS rat model revealed better treatment response by showing several evidence such as signs of remyelination, restoration of neuron shape, and the recovered oligodendrocytes.

Comparison with existing methods: To the best of our knowledge this article demonstrates improved efficacy of FNG using SLNs.

Conclusion: This study demonstrates the successful development of FNG-SLNs to enhance the therapeutic efficacy of FNG for the treatment of multiple sclerosis.

Background: Electroencephalogram (EEG)-based speech imagery is an emerging brain-computer interface paradigm, which enables the speech disabled to naturally and intuitively communicate with external devices or other people. Currently, speech imagery research decoding performance is limited. One of the reasons is that there is still no consensus on which domain features are more discriminative.

New method: To adaptively capture the complementary information from different domain features, we treat each domain as a view and propose a multi-view graph fusion of self-weighted EEG feature representations (MVGSF) model by learning a consensus graph from multi-view EEG features, based on which the imagery intentions can be effectively decoded. Considering that different EEG features in each view have different discriminative abilities, the view-dependent feature importance exploration strategy is incorporated in MVGSF.

Results: (1) MVGSF exhibits outstanding performance on two public speech imagery datasets (2) The learned consensus graph from multi-view features effectively characterizes the relationships of EEG samples in a progressive manner. (3) Some task-related insights are explored including the feature importance-based identification of critical EEG channels and frequency bands in speech imagery decoding.

Comparison with existing methods: We compared MVGSF with single-view counterparts, other multi-view models, and state-of-the-art models. MVGSF achieved the highest accuracy, with average accuracies of 78.93% on the 2020IBCIC3 dataset and 53.85% on the KaraOne dataset.

Conclusions: MVGSF effectively integrates features from multiple domains to enhance decoding capabilities. Furthermore, through the learned feature importance, MVGSF has made certain contributions to identify the EEG spatial-frequency patterns in speech imagery decoding.

Background: Temporal Interference Stimulation (TIS) is a non-invasive approach to deep brain stimulation. However, most research has focused on the intensity of modulation, with limited attention given to the directional properties of the induced electric fields, despite their potential importance for precise stimulation.

New methods: A novel analytical framework was developed to analyze TIS-induced electric field directions using individual imaging data. For each voxel, the direction corresponding to the maximal modulation depth was calculated. The consistency of these directions within regions of interest (ROIs) and their alignment with the ROI principal axes, derived from principal component analysis (PCA), were assessed.

Results: Simulations revealed complex spatial and temporal trajectories of the electric field at the voxel level. In the left putamen, the maximal modulation depth reached 0.241 ± 0.041V/m, whereas in the target region, the left hippocampus, it was lower (0.15 ± 0.032V/m). Notably, in the left hippocampus, the directions of maximal modulation depth were predominantly perpendicular to its longitudinal axis (84.547 ± 8.776°), reflecting structural specificity across its anterior, middle, and posterior regions.

Comparison with existing methods: Unlike previous approaches, this study integrates directional analysis into TIS modeling, providing a foundation for precise stimulation by exploring structural alignment.

Conclusion: Our analysis revealed that the orientations of maximal modulation depth in the left hippocampus were perpendicular to its longitudinal axis under the current electrode configuration, but they shifted to parallel alignment when the electrode pairs were swapped. This directional specificity offers insights for optimizing TIS by aligning with structural features, presenting a potential strategy to enhance stimulation precision and broaden its clinical and research applications.

Background: Pediatric epilepsy significantly affects cognitive and developmental outcomes, with drug-resistant epilepsy (DRE) posing a major challenge. While pharmacological and surgical interventions remain standard treatments, they often fail in refractory cases. Non-Invasive Brain Stimulation (NIBS), including Transcranial Magnetic Stimulation (TMS) and Transcranial Direct Current Stimulation (tDCS), has emerged as a promising therapeutic alternative.

New method: This study systematically reviews and compares the efficacy, safety, and feasibility of TMS and tDCS in pediatric epilepsy. The analysis evaluates seizure reduction, cognitive improvements, and treatment tolerability. A comparative assessment considers mechanisms of action, precision, accessibility, and clinical applications.

Results: TMS and tDCS treatments produce a 30-40% seizure reduction effect in addition to attaining enhanced attention and memory functions. TMS provides top-level spatial precision but tDCS allows low-cost portable treatment that suits home use. Studies show that patients experience minimal and short-term discomfort on their scalp but only minor headaches as reported side effects.

Comparison with existing methods: Compared to pharmacological treatments, NIBS offers a non-invasive alternative with fewer systemic side effects. Unlike surgery, which requires invasive intervention, NIBS is safe, repeatable, and adaptable. However, cost (TMS), lack of standardization, and patient response variability remain challenges to clinical adoption.

Conclusions: NIBS is a safe and effective alternative for pediatric epilepsy but requires protocol standardization, accessibility improvements, and long-term efficacy validation. Future research should focus on biomarker-driven personalized treatments, AI-optimized stimulation, and affordable device development for broader clinical applications.

Background: Evolutionary biology and neuroscience evidence supports the theory that spatial cognition and social cognition share neural mechanisms. Although rodent models are widely used to study either spatial or social cognition, few studies have explored the interactions between these domains, possibly because measures across tasks differ.

New method: We introduce the automated 3-dimensional Vertical Maze (VM), a new model system designed to measure multiple aspects of spatial and social behavior and cognition. The VM features a standard 3-chamber maze positioned above three-level columns allowing for presentation of conspecifics as either demonstrators or discriminative stimuli at different spatial distances and different social familiarity levels. The presentation of demonstrators below the perforated floors of the 3-chamber level encourages rats to use multisensory cues to judge distance, direction, and social identity of conspecifics.

Results: Using the VM, we found that rats showed normal social preferences whether demonstrators were presented at the near, middle, or far distance. In an operant spatial distance discrimination task, rats readily learned to associate a reward with the spatial distance of a demonstrator.

Comparison with existing methods: This new paradigm advances the field by permitting the presentation of social information (conspecifics) at different spatial distances allowing more direct comparison of behavioral measures across social and spatial information domains.

Conclusions: The VM is an effective tool for studying both spatial and social cognition opening new avenues for investigating the neural and cognitive foundations of spatial and social behavior and for exploring the possibility of shared mechanisms across these cognitive domains.

Background: Preclinical rodent models have been crucial for studying stroke pathophysiology. However, the limited success of translating these ischemic stroke models to human trials highlights their shortcomings. To address this, we developed a large animal porcine stroke model using Rose Bengal (RB) for photothrombotic ischemic lesioning.

New method: Four Danish Landrace pigs (4-6 months old, 36-40kg) were used in this proof-of-concept study. RB (20mg/kg) was infused via a central venous catheter, and lesion sites in the motor and visual cortices were targeted using MRI, a stereotactic frame, and fiducial markers. Surgical access was achieved through burr holes, followed by green light exposure through the dura onto the neocortex for 30minutes. After recovery, the pigs underwent motor behavior assessment, euthanasia, and histological and MRI analyses.

Results: Post-stroke, significant motor deficits were observed. Three pigs were hemiparetic and immobile, while one showed reduced exploratory behavior (42% post-stroke vs. 81% pre-stroke) and peripheral sniffing (~0% vs. 9%). Histological analysis revealed ischemic changes, including nuclear shrinkage, pyknosis, and infarct zones with blood clots. Lesion size ranged from 1mm² to 18mm². Ex vivo diffusion MRI showed increased mean kurtosis in three pigs, confirming microstructural changes.

Comparison with existing methods and conclusions: The model produced behavioral and histological characteristics in pigs, which have gyrencephalic brains, large intracranial vessel diameters, and a high white-to-gray matter ratio, similar to those observed in other animals and traditional models. This model can produce a reproducible isolated cortical lesion using stereotactic coordinates and/or 3D imaging.