The study of the nature of motor pathologies is one of the most important areas in physiology and medicine. The purpose of this work was to assess the functional state of the neuromotor apparatus of the soleus muscle (SM) in middle-aged male rats under conditions of long-term hindlimb unloading (HU). Experiments were carried out in strict accordance with accepted bioethical standards. The animals were divided into three groups: hinlimb unloading (HU), HU with magnetic stimulation (HU+MS), and the electrical stimulation of the spinal cord (HU+ES). Parameters of motor and reflex responses were recorded. The threshold of the SM reflex response was reduced to 81±8% (p<0.05) in the HU group, 77±10% (p<0.05) in the HU+ES group, and 73±16% (p<0.05) in the HU+MS group. The amplitude of the SM H-response increased to 130±15% (p<0.05)in the HU group, 121±9% (p<0.05) in the HU+ES group, and 120±10% (p<0.05) in the HU+MS group. The amplitude of the M response was 73±11% (p<0.05) in the HU group, 76±9% (p<0.05) in the HU+ES group, and 70±15% (p<0.05) in the HU+MS group. Thus, during long-term hindlimb unloading, we recorded an increase in the reflex excitability of the spinal motor center of the SM. And we also found that spinal cord stimulation prevented changes in the threshold of the M-response of the SM, but did not exclude a decrease in amplitude. The research was funded by a grant from the Russian Science Foundation and the Academy of Sciences of the Republic of Tatarstan under project no. 23-25-10065.

When humans encounter the same disturbance twice, they adapt to it faster during the second exposure. To examine how subconscious learning systems contribute to this savings process, previous studies have suppressed explicit awareness of the perturbation by gradually increasing its magnitude during initial learning. This has produced mixed effects, with some studies demonstrating faster relearning, and others observing no acceleration during relearning. Here, we examined whether these differences might be due to the nature of a de-adaptation period that separates two learning periods. To test this idea, we manipulated the magnitude of washout errors by de-adapting participants abruptly, gradually, or by removing feedback entirely. Empirical analyses indicated that the different classes of washout errors had a profound effect on savings: large washout errors nullified the ability to save, whereas small errors or the absence of error protected savings. Model-based analyses suggested that changes in learning rates were mediated by an increase in sensitivity to error that could be reversed by experience with oppositely oriented washout errors. This suggests that the experience of error produces both a facilitation of learning for similar errors and a reduction in learning for dissimilar errors. The latter can abolish the expression of savings following gradual adaptation.

This study reconstructs the spatial layout of the Kunsthaus Hamburg using blurred photographs and transparent originals to gain insights into memory, perception, and cognition. We investigate mental models and visual representations during museum navigation in the 2009 and 2019 visits by employing a philosophical behavioural approach based on vignettes’ logics—scenarios exploring cognitive processes in constructing hypothetical stories. The study examines factors influencing deviations from planned routes, cognitive mechanisms behind selecting perspectives in photographs, and environmental awareness at image capture.

A hierarchy way of finding the orientation (HWO) algorithm breaks down the space into a hierarchy of nodes (rooms) and edges (pathways), determining the initial position within the museum based on the first clear photograph and the known layout. A hierarchical map categorizes nodes and edges by importance and connectivity, with major sections forming the top level and individual rooms forming the lower levels. Random forests classify images of rooms and predict the sequence of rooms visited based on features extracted from clear photographs. A labelled dataset of fifty room photographs was used to train the random forest model, which then classified the blurred photographs and combined this with the HWO algorithm to predict the sequence of rooms visited.

The study acknowledges biases such as inaccurate architectural measurements and the Halo effect. Insights from Rehkämper (2006) and Guilherme (2019) were applied to understand the interplay between mental models, expectations, and new information. This framework for reconstructing spatial layouts from blurred photographs provides insights into the spatial cognition and the dynamic nature of mental models.

Introduction: Hemispatial neglect post-right middle cerebral artery (MCA) stroke can be effectively addressed with spatial awareness rehabilitation techniques, such as Augmented Reality (AR), which utilize gamification to stimulate the neglected side, enhance patient engagement, and potentially improve outcomes. This study introduces an AR-based Dual-Task Neglect System (DTNS) specifically designed to rehabilitate hemispatial neglect.

Methods: The DTNS comprises two tasks aimed at assessing and rehabilitating hemispatial neglect in real-world settings. Task 1 involves a dragon navigation game where patients use a joystick to guide a dragon toward moving crystals (n=3) of varying speeds and colors, projected into their neglected visual field in real space, which helps clinicians evaluate the extent of neglect. Task 2 is a reward-based rehabilitation coin collection game where patients use touch input to gather coins appearing in real space within a set time. Performance is based on coins collected. Task 1 is reassessed after Task 2 to track improvements. The system's functionality and usability were tested on healthy participants (n=13) aged 17-65, with feedback guiding app refinements. Future work involves testing hemispatial neglect patients.

Results: Younger participants (17-40) found both tasks to be engaging, manageable, and motivating, with no adverse effects observed. Older participants (41-65) also found the tasks engaging, though the coin collection task was considered moderately challenging. All participants perceived DTNS as more motivating and engaging compared to traditional therapies.

Conclusion: The DTNS demonstrates potential as a motivational tool for hemispatial neglect rehabilitation, engaging patients through targeted body movement stimulation and potentially enhancing spatial awareness over time.

Brain plasticity plays a critical role in the coordination of brain functions, particularly considering that the hippocampus is one of the most important areas in the brain. This study aims to investigate and analyze the hippocampal pathways using three types of plasticity and two computational methods. In this research, the rules of Hebbian plasticity, homeostatic plasticity, and plasticity dependent on the synchrony of dendritic activity have been used. Python programming language and Nest library are also among the tools of this project.
The first method is using the Leaky Integrate-and-Fire (LIF) model. For this purpose, we have used biological neural networks in which neurons are considered as nodes, synapses as connections, and different types of plasticity as network properties. This method can simulate connectivity among neurons as well as their activity. The second method uses a directed random graph model to simulate only the connectivity of the circuit.
In both simulations, the number of neurons, the excitation and inhibition balance, and the connection probability have been chosen carefully to reflect the real properties of the circuit. Both models show agreement with the connectivity pattern of the hippocampus obtained from experimental studies. The strength of connections matches the experimental results of the hippocampus in the first model. In contrast, due to the lack of activity simulation in the second model, the strength of network synapses differs from experimental results as it is a mathematical model and aims to partially reflect the properties of biological neural networks.

Migraine is a prevalent neurological disorder. The anatomical structure responsible for the pain caused by migraine is the trigeminovascular system. Carbon monoxide (CO) is a gas that can induce headache due to its toxicity, but when produced endogenously can regulate cerebral blood flow, nociception and neurotransmission; however, its role in the trigeminovascular system has not been investigated. The aim of our study was to analyze the effects of exogenous CO on the TRPV1 receptor-mediated activity of the rat TG nerve.

Action potentials (APs) of the trigeminal nerve were recorded using na extracellular electrode in a rat hemi-skull preparation. Capsaicin (1 µM) was used as an agonist of TRPV1 receptors; CORM-II (60 µM) was used as a CO donor, and MDL 12,330A (10 µM) was used as an inhibitor of adenylyl cyclase.

In control conditions, trigeminal nerve afferents demonstrated spontaneous regular activity. The application of the CO donor CORM-II resulted in a significant increase in the frequency of APs. The application of capsaicin induced a significant increase in the frequency of APs, which persisted for approximately one to two minutes until the TRPV1 receptors became desensitized. Application of capsaicin after incubation in CORM-II increased the duration of the capsaicine effect to 4-6 minutes. Preliminary inhibition of adenylyl cyclase by MDL prevented this effect.

In conclusion, the CO donor has pro-nociceptive effects on the afferents of the trigeminal nerve, and promotes TRPV1 receptor-mediated activity through adenylate cyclase. Further investigation is necessary to reveal the mechanisms of CO action in the trigemino-vascular system and its impact in nociception.

This work was supported by the Russian Science Foundation (№ 20-15-00100)

Homocysteine is a sulphur-containing amino acid synthesised from methionine. An increase in homocysteine concentration during pregnancy has been linked to an elevated risk of neuropathological diseases. The hippocampus, which plays a pivotal role in numerous functions, represents a crucial area of focus in understanding the effects of hyperhomocysteinemia. This study aimed to investigate the impact of prenatal hyperhomocysteinemia on the development of NMDA receptors in the early postnatal period. The experiment was conducted on Wistar rats. Pups with prenatal hyperhomocysteinemia were born from females who received daily methionine with food. Horizontal slices of the hippocampus were obtained from the rats at age P10-11. CNQX and bicuculline were used to block AMPA and GABA receptors, respectively. The whole-cell patch clamp method was employed to record evoked responses. The stimulation protocol comprised five bursts of five pulses at a frequency of 100 Hz, with an interval of 200 ms between bursts. Biexponential analysis was employed to analyse the decay phase, resulting in a significant reduction in the fast component of decay and an increase in the slow component of decay in the experimental group compared to the control group. Concurrently, no considerable alterations in the amplitudes of peaks normalised to the first peak were observed. The results may indicate a change in the subunit composition of hippocampal NMDA receptors, which may indicate a disruption in the transition from GluN2B and GluN2D (slow) subunits to GluN2A (fast).

Oxysterols are products of cholesterol oxidation and play important roles in a number of processes, including signaling, development, metabolism, membrane homeostasis, inflammation and immune function. It has been demonstrated that 24S-hydroxycholesterol (24-OHC) can modulate neuronal functions, with potential relevance to the hyperexcitability underlying seizures. 24-OHC is produced in a brain by the CYP46A1 enzyme from cholesterol. The goal of our study was to investigate the relationship between the serum levels of 24-OHC in mice and the development of seizures in a kindling animal model induced by pentylenetetrazol (PTZ).

Outbred mice were injected with subthreshold dosages of PTZ (35 mg/kg) every other day for 30 days. Seizure activity was assessed using the Racine scale. To achieve a reduction in cholesterol 24-OHC levels in the brain, we used the inhibitor of CYP46A1, voriconazole (60 mg/kg, n=10), and for increasing 24-OHC levels, we used a low dose of efavirenz (0,09 mg/kg, n=10). We also included a control group control group (n=10). Voriconazole was injected peritonial for 5 days before PTZ treatment, and efavirenz was delivered perorally for 2 weeks before PTZ treatment. Both substances had a maintenance course during PTZ treatment.

During voriconazole treatment, the onset of epilepsy was delayed and the number of ensuing seizures was decreased compared to those in vehicle-treated mice. The augmentation of 24-OHC levels induced high-grade and -intensity seizures. The duration and onset of seizure did not change compared to that in the control group.

Thus, the experimental data show that changing 24S-hydroxycholesterol levels in the blood of mice may contribute to the development of PTZ-induced seizures.

Introduction:

Humans have complex neuronal mechanisms associated with intricate psychological perspectives in respect to mate selection. The neuropsychological manifestations responsible for mate choice behavior are manipulated by chronic exposure to extensive erogenous content on digital social media, which initiate erratic behavioural patterns during mate choice. In this research work, confusion is considered a fundamental behaviour where humans face difficulties in decision-making. In our assessment, we tried to indicate that confusion is one indecisive behavioral pattern which can eventually affect mate choice in young adult humans.

Method:

This study is a fundamental observational assessment of human erratic behaviour followed by an open questionnaire, responded to by 150 people . The population comprised young adults between the age of 18 and 30 years.

Results:

Results strongly indicated confusion in selecting mating partners. The surveyed population demonstrated an increased confusion index in females compared with that in males.

Conclusion:

We conclude that confusion is a potential marker of erratic behavior in humans. With the significant shift from analogue to digital lifestyles, the human population is encountering extensive virtual ‘attractive’ data which have created a big dataset for stimulating content, leading to confusion while selecting a partner. Digital social platforms are influencing complex thought processes, thus altering normal reproductive behaviour in humans. The brain–behavior–digitalization axis in today’s world is challenging the evolutionary aspects of human interaction, which is manifested in recent human behavioral patterns, many of which are an issue of concern for society.

Introduction: Cross-linguistic studies offer unique and new insights into the relationship between language and cognition and the impact of linguistic differences on the diagnostic process in neurological conditions. However, differences in speech production among healthy speakers have been scarcely investigated. We aim to address cross-linguistic variability in the connected speech production of English, Chinese (Mandarin and Cantonese), and Italian speakers using a picture description task.

Methods: Thirty-nine sex-, age-, and education-matched subjects (thirteen for each language) described the Picnic scene from the WAB battery. Twenty-eight linguistic features encompassing phonological, lexico-semantic, morpho-syntactic, and discourse/pragmatic domains were then coded using a semi-automated computerized language analysis program (CLAN). The frequency of each feature was compared across the three groups.

Results: While the majority of features were similar across languages, we identified differences among English, Chinese, and Italian speakers. Specifically, we found reduced production of prepositions, conjunctions, and pronouns, and increased adverb use in the Chinese-speaking group compared to the groups speaking the other two languages. English participants produced a higher proportion of prepositions, while Italian speakers produced significantly more conjunctions and empty pauses than the other groups.

Conclusions: Our results support the role of cross-linguistic studies in capturing language-specific nuances in spoken production and highlight the need for linguistically tailored tools for the assessment of language performance.