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A recent study conducted at Shenzhen University in China explored the effects of temporal interference (TI) stimulation on dynamic functional connectivity (dFC) in the motor cortex. The research found that TI stimulation at 20 Hz frequency altered dFC in the primary motor cortex, leading to decreased variability and increased mean connectivity strength. This study sheds light on the neuromodulatory effects of TI stimulation on brain networks, providing valuable insights into the dynamic mechanisms underlying its impact on neuronal activity. [Extracted from the article]

The article discusses how the brain not only processes what we see but also continuously makes predictions based on our experiences. Researchers have found that the brain predicts future events based on expectations and previous experiences, allowing us to react quickly to stimuli. The article also explores how individuals with autism may have a less finely-tuned predictive system, leading to a more unpredictable world for them. The brain's ability to make predictions helps us navigate our surroundings and adapt to different situations. [Extracted from the article]

Researchers at the Second Affiliated Hospital of Nanchang University conducted a study using functional near-infrared spectroscopy (fNIRS) to investigate age-related differences in brain activation during various motor control conditions in younger and older adults. The study found that levels of oxyhemoglobin (HbO2) in different brain regions varied between age groups during motor execution, motor passivity, and motor imagery tasks. The research suggests that age can influence HbO2 levels in the brain during different motor control conditions. The study was published in the Journal of Integrative Neuroscience and can be accessed for free online. [Extracted from the article]

The article discusses rapid-onset dystonia-parkinsonism (RDP), a rare neurological disorder caused by mutations in the ATP1A3 gene. Experimental studies suggest that the pathophysiology of RDP involves dysfunction in the cerebellum, basal ganglia, and motor cortex. The study aimed to characterize neuronal network activity in these areas using an ouabain model in rats, revealing specific oscillations associated with dystonia and parkinsonism. This preprint has not been peer-reviewed and provides valuable insights into the network mechanisms underlying RDP. [Extracted from the article]

The article discusses the potential role of cortico-motoneuronal projections in enhancing vocalization abilities in mice. Researchers hypothesize that a direct connection from motor cortex layer 5 neurons to brainstem vocal motor neurons may enable fine motor control of vocal laryngeal musculature in vocal learners. By manipulating axon-guidance receptors in mice, the study found that enhanced cortical projections to vocal motor neurons led to increased functional connectivity to phonatory muscles and a wider range of vocal abilities. This research suggests that direct vocal cortico-motoneuronal projections may influence vocal behaviors in mice. [Extracted from the article]

The article discusses a study on changes in cortical activity related to grasping behavior before and after object contact. The research focused on analyzing sensorimotor signals in the primary motor cortex and somatosensory cortex of macaque monkeys. The findings suggest that different areas of the cortex carry object-specific information, with some signals being altered by contact with the object. The study highlights the complex neural processes involved in grasping behavior and the diverse activity within the sensorimotor cortex. [Extracted from the article]

A study conducted at Nippon Medical School in Tokyo, Japan, explored the deactivation of the supplementary motor area (SMA) during mental rotation tasks with biomechanical constraints using fMRI. The research involved 20 healthy right-handed participants who were asked to determine whether rotated hand-palm images were of a right or left hand. The study found a significant negative correlation between the angle of rotation and brain activity in the SMA, suggesting that biomechanical constraints may be associated with SMA deactivation. This research provides insights into the neurophysiological mechanisms of motor imagery and could potentially inform treatment plans for patient rehabilitation. [Extracted from the article]

The article discusses the gradual consolidation of skilled sequential movements in the primary motor cortex of non-human primates. It highlights the role of the primary motor cortex in acquiring and retaining sequential movements through extensive practice, with evidence of reorganization in the cortex following prolonged practice. The study used a protein synthesis inhibitor to disrupt memory consolidation in the motor cortex during learning, showing that inhibiting protein synthesis affected memory-guided performance at all stages of learning, with the rate of consolidation slowing as learning progressed. [Extracted from the article]

The article discusses the representation of verbal thought in the motor cortex and its implications for speech neuroprostheses. Through multi-unit recordings in participants with dysarthria, researchers found a strong neural encoding of inner speech, allowing for real-time decoding of individual words and imagined sentences. The study also explored concerns about privacy and the potential for decoding private verbal thoughts, highlighting design considerations and risks as speech neuroprostheses become more widespread. The preprint has not yet undergone peer review. [Extracted from the article]

The article discusses the presence of conflict neurons in the cingulate cortex of macaque monkeys, which are believed to play a role in cognitive control. While previous studies have shown conflicting results regarding the presence of these neurons in the cingulate cortex, the current research suggests that they are indeed present, albeit in a small fraction of neurons. Further investigation is needed to determine the significance of this weak conflict signal in the cingulate cortex. The study has not yet undergone peer review and is available for more information on biorxiv.org. [Extracted from the article]

A study conducted at Xi'an University of Science and Technology in China explored the impact of high temperatures and humidity on miners' working memory using functional near infrared spectroscopy (fNIRS). The research found that high temperature and humidity conditions significantly affected reaction times and working memory, with temperature having a more pronounced impact than humidity. The study emphasizes the importance of optimizing miners' work environments to improve productivity and safety. [Extracted from the article]

A preprint abstract from biorxiv.org discusses a study on the motor cortices of non-human primates, specifically rhesus macaques, to gain insight into human motor control and movement disorders. The researchers used calcium imaging and miniature microscopes to examine the activity patterns of projection neurons in the supplementary motor and primary motor areas of the macaques. They implanted gradient index lenses and expressed GCaMP6f to track calcium transients while the animals were at rest or engaged in an arm reaching task. The study demonstrates the value of in vivo calcium imaging for studying patterns of activity in groups of corticofugal neurons in the motor cortices. [Extracted from the article]

According to a preprint abstract, researchers have found that the secondary motor cortex (M2) plays a crucial role in motor learning. They used Ca2+ imaging to record neuronal population activity during motor learning and discovered the evolution of attractors in the M2 cortex. These attractors contribute to the decrease in variation in motor behavior during training and provide a framework for understanding the relationship between motor learning and neural structure. This research has not yet undergone peer review. [Extracted from the article]

According to a preprint abstract from biorxiv.org, researchers conducted a study to understand the distinct functional roles of two types of layer 5 neurons in the motor cortex: corticorubral (CR) neurons and corticospinal (CS) neurons. They selectively inhibited these neurons in rats during lever movement execution and found that CR neuron inhibition affected various kinematic parameters, while CS neuron inhibition mainly altered the duration, speed, and acceleration of the movement. The researchers concluded that CS and CR neurons are complementary pathways for transmitting information rather than duplicates of the same motor command. This research has not yet undergone peer review. [Extracted from the article]

This article discusses a study on low-intensity focused ultrasound (LIFU) as a form of non-invasive neuromodulation. The study aimed to understand how different parameters, such as intensity, duration, duty cycle, and pulsing strategy, interact to produce effects in the human brain. The study involved 18 healthy human volunteers who underwent 20 different parameter combinations. The results showed that LIFU either conferred inhibition or had no effect, with no evidence of excitation. Lower intensity and pulsed ultrasound were found to be more effective for inhibition. However, it is important to note that this study is a preprint and has not been peer-reviewed. [Extracted from the article]

A report from Murdoch University in Perth, Australia discusses recent advances in neuroscience. The research focuses on the effects of beta transcranial alternating current stimulation (tACS) on connectivity within the motor network. The study found that the intensity and frequency of stimulation influenced the connectivity between the left and right primary motor cortices. These findings have implications for both research and clinical applications in the field of neuroscience. [Extracted from the article]

A recent neuroscience study conducted at Otto-von-Guericke-University Magdeburg in Germany explored age-related differences in cortical microstructure and their relationship to the nearby veins in the brain. The researchers used 7 Tesla MRI to measure changes in brain structure in younger and older adults. They found that cortical microstructure and age-related changes were influenced by the distance to the nearest vein. These findings suggest that the local venous architecture should be considered in models of brain organization and aging. The full article can be accessed for free through Oxford University Press. [Extracted from the article]

A recent study challenges the traditional understanding of how the body is represented in the motor cortex of the brain. The study used microelectrode array recordings from eight individuals to create a comprehensive map of the human motor cortex at the single neuron level. Contrary to previous beliefs, the study found whole-body representations throughout all sampled points of the precentral gyrus (PCG), which contradicts the traditional boundaries for the arm, leg, and face. The findings suggest that the motor cortex may be better described as a mosaic of functional zones, each with its own whole-body representation. However, it is important to note that this study has not yet undergone peer review. [Extracted from the article]

A recent study investigated the effects of low-frequency repetitive transcranial magnetic stimulation (rTMS) on the consolidation of balance skills. The study found that rTMS over the primary motor cortex impaired the consolidation of a balance task by suppressing the up-regulation of intracortical inhibition. Participants who received rTMS showed declines in performance in subsequent sessions, while those who received sham-rTMS showed improvements. The study suggests that increased intracortical inhibition is important for protecting and consolidating newly acquired motor memory. However, it should be noted that this study has not yet undergone peer review. [Extracted from the article]

This article discusses a study that investigated the relationship between the mu rhythm phase and cortical excitability in individuals with brain lesions after a stroke. The study used electroencephalography (EEG) signals and transcranial magnetic stimulation (TMS) to measure motor-evoked potentials (MEPs) and local cortical activation. The results showed that individuals with stronger stroke-related motor symptoms had a decreased phase preference, and the phase-dependency was abolished in the stroke-affected hemisphere. These findings suggest that the strength of phase preference of TMS motor responses could indicate the severity of motor impairment and could potentially be used to develop improved TMS paradigms for stroke recovery. [Extracted from the article]

A preprint abstract from biorxiv.org discusses the development of a method for creating an intracortical brain-computer interface (iBCI) that can seamlessly transition between tasks and contexts. The method uses an unsupervised approach that relies on the structure of a low-dimensional neural manifold to implement a piecewise linear decoder. The researchers recorded neural signals from the motor cortex and electromyographs from upper limb muscles while monkeys performed various tasks. The results suggest that a piecewise linear decoder can effectively approximate the nonlinearity between neural activity and motor outputs. However, it is important to note that this preprint has not been peer-reviewed. [Extracted from the article]

A preprint abstract discusses a study that aimed to develop a rat model that replicates the effects of transcranial magnetic stimulation (TMS) in humans. The study involved two cohorts of rats, with one group receiving TMS for five days and the other group serving as a control. The results showed that the rats receiving TMS had enhanced cortical excitability and increased basal brain activity in certain regions compared to the control group. This research provides a platform for further investigation into TMS-induced plasticity. However, it is important to note that this preprint has not yet undergone peer review. [Extracted from the article]

Researchers at the Sainsbury Wellcome Centre at UCL have discovered two distinct maps in the brain's secondary motor cortex that are involved in spatial planning and navigation. The maps use a self-centered coordinate system and a world-centered map to determine the body's position in the world. This research could have implications for understanding neurological conditions that affect spatial attention, such as stroke. The researchers used a novel task in rats to differentiate between self-centered and world-centered reference frames and recorded neural activity to decode the information. They are now exploring how these dual maps are used in tasks and studying more complex sequences of movements to further understand spatial attention and its connection to planning and execution of orienting movements. [Extracted from the article]

A recent study utilized dual-coil paired-pulse transcranial magnetic stimulation (ppTMS) to investigate the connectivity between the supplementary motor complex (SMC) and the primary motor cortex (M1) in humans. The study found a robust facilitatory connection between the SMC and M1, resulting in a 19% increase in motor-evoked potentials. Importantly, this facilitatory influence was only observed when the preconditioning stimulation was administered at a specific distance from the Cz point. The findings highlight the importance of spatial specificity in modulating the SMC-M1 circuitry. Please note that this study has not yet undergone peer review. [Extracted from the article]

Researchers from Jiangsu, China have conducted a study to investigate the effects of preconditioning intermittent theta burst stimulation (iTBS) on the excitability of the lower extremity motor cortex in healthy individuals. The study involved 25 participants who underwent three different TBS protocols. The results showed that preconditioning the lower extremity motor cortex with continuous theta burst stimulation (cTBS) prior to iTBS intervention enhanced its excitability, with the effect lasting for at least 20 minutes. This study provides valuable insights into the potential use of TBS protocols in enhancing motor cortex excitability. [Extracted from the article]

This article discusses a study that investigated the long-range axonal projections of different classes of neurons in the whisker-related somatosensory cortices of mice. The researchers used brain-wide light-sheet imaging to examine the axonal output of genetically-defined projection neurons. They found that these neurons had diverse downstream brain targets, with distinct innervation patterns based on their genetic cell classes. The study also explored the functional circuits underlying these axonal projections and highlighted the importance of understanding the complex neuronal circuitry in the brain. Please note that this preprint has not yet undergone peer review. [Extracted from the article]

This article discusses a study that aims to understand how different regions of the brain coordinate to produce cognition. The researchers used rats performing a decision-making task to study the simultaneous interactions between up to 20 brain regions. They found a network of strongly correlated brain regions involved in evidence accumulation, and these correlations ceased at the time of decision commitment. The study suggests that evidence accumulation involves coordination within a network of frontal cortical and striatal regions, with termination of the process potentially initiating in the primary motor cortex. [Extracted from the article]

A recent study investigated the structural development of the neural speech network in young children at risk for speech disorders. The study used diffusion weighted imaging (DWI) magnetic resonance imaging (MRI) to scan 94 children aged 4-7 years old. The results showed that individual differences in speech performance were reflected in structural gray and white matter differences, particularly in the cerebellum and cortical association fiber pathways. These findings provide important insights into the developing brain networks that support speech in very young children. However, it is important to note that this study has not yet undergone peer review. [Extracted from the article]

A preprint abstract from biorxiv.org discusses the limitations of independent component analysis (ICA) in capturing nonlinear relationships in resting functional magnetic resonance imaging (fMRI) data. The authors propose an enhanced connectivity-domain ICA approach called connectivity-matrix ICA, which incorporates normalized mutual information (NMI) to measure explicitly nonlinear (EN) relationships within voxel connectivity. By eliminating linear dependencies and utilizing NMI, the authors discover highly structured resting networks that conventional functional connectivity methods would typically overlook. The authors also evaluate differences in the identified networks in a schizophrenia dataset, finding significant global differences between schizophrenia and control groups in some linear-EN maps. The findings highlight the importance of accounting for explicitly nonlinear dependencies in functional connectivity analysis and demonstrate the effectiveness of the extended cmICA approach in revealing previously unrecognized brain dynamics. [Extracted from the article]

A recent study investigated the use of combined transcranial magnetic stimulation and electroencephalography (TMS-EEG) to probe cortical excitability at the network level. The study found that immediate TMS-evoked potentials (i-TEPs) after primary motor cortex (M1) stimulation may represent a local response. The researchers analyzed a TMS-EEG dataset from 28 healthy participants and confirmed the presence of i-TEPs with similar characteristics as previously described. They also found that the immediate TMS-related power (i-TRP) revealed strong activity in two ranges and was positively associated with motor-evoked potentials (MEPs) amplitude. The findings suggest that i-TRP represents a direct measure of excitability of the stimulated cortex. [Extracted from the article]

A recent study investigated the role of the ipsilateral motor cortex in rat movement following a spinal cord injury. The researchers combined a spinal cord injury with a cortical neuroprosthetic approach and found that stimulation of the ipsilesional motor cortex promoted bilateral synergy in all rats, resulting in the elevation of the contralateral foot and ipsilateral hindlimb extension. Additionally, in some animals, stimulation of a sub-region of the hindlimb motor cortex modulated ipsilateral hindlimb flexion. The study suggests a causal link between cortical activation and precise ipsilateral control of hindlimb movement, which has implications for the development of neuroprosthetic technology and our understanding of motor control in spinal cord injury. [Extracted from the article]