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Zhong Nan Da Xue Xue Bao. Yi Xue Ban =... Jul 2022Studies on the influence of motor imagery (MI) on brain structure and function are limited to traditional imaging techniques and the mechanism for MI therapy is not...
OBJECTIVES
Studies on the influence of motor imagery (MI) on brain structure and function are limited to traditional imaging techniques and the mechanism for MI therapy is not clear. By observing the brain activation mode during MI and motor execution (ME) in healthy adults, this study aims to use near-infrared brain imaging technology to provide theoretical basis for the treatment of MI.
METHODS
A total of 30 healthy adults recruited to the public from June 2021 to August 2021. The MI and ME of the right knee movement served as the task mode. Block design was repeated 5 times alternately in a 20 s task period and a 30 s resting period. The activation patterns of brain regions were compared between the 2 tasks, and the regression coefficient was calculated to reflect the activation intensity of each brain region by Nirspark and SPSS 23.0 softwares.
RESULTS
Lane 2, 3, 4, 5, 7, 9, 19, 20, 21, 24, 25, 26, 27, 32, 33, and 34 were significantly activated during the ME task (<0.05, corrected by FDR) and lane 2, 5, 9, 16, 27, 29, 33, 34, and 35 were significantly activated during the MI task (<0.05, corrected by FDR). According to the channel brain region registration information, the brain region activation pattern was similar during both MI and ME tasks in healthy adults, including left primary motor cortex (LM1), left primary sensory cortex (LS1), prefrontal pole, Broca area, and right supramarginal gyrus. Both LM1 and left pre-motor cortex (LPMC) were activated during MI in healthy adults, whereas dorsolateral prefrontal cortex (DLPFC) and only LM1 of the motor region were activated during ME. Compared to MI, the activation intensity of left sensory and left motor cortex was significantly enhanced in ME, and that of left and right prefrontal cortex especially left and right pars triangularis Broca's area (<0.001, corrected by FDR) were significantly enhanced.
CONCLUSIONS
The rationality of MI therapy is proved by functional near-infrared spectroscopy. The involvement of DLPFC in motor decision-making may regulate the two-way feedback of premoter cortex-M1 during ME; and Broca area, closely related to the motor program understanding, participates in MI and ME.
Topics: Adult; Brain Mapping; Humans; Imagination; Motor Cortex; Movement; Spectroscopy, Near-Infrared
PubMed: 36039589
DOI: 10.11817/j.issn.1672-7347.2022.210689 -
International Journal of Molecular... Aug 2020Rodent neocortical neurons undergo prominent postnatal development and maturation. The process is associated with structural and functional maturation of the axon...
Rodent neocortical neurons undergo prominent postnatal development and maturation. The process is associated with structural and functional maturation of the axon initial segment (AIS), the site of action potential initiation. In this regard, cell size and optimal AIS length are interconnected. In sensory cortices, developmental onset of sensory input and consequent changes in network activity cause phasic AIS plasticity that can also control functional output. In non-sensory cortices, network input driving phasic events should be less prominent. We, therefore, explored the relationship between postnatal functional maturation and AIS maturation in principal neurons of the primary motor cortex layer V (M1LV), a non-sensory area of the rat brain. We hypothesized that a rather continuous process of AIS maturation and elongation would reflect cell growth, accompanied by progressive refinement of functional output properties. We found that, in the first two postnatal weeks, cell growth prompted substantial decline of neuronal input resistance, such that older neurons needed larger input current to reach rheobase and fire action potentials. In the same period, we observed the most prominent AIS elongation and significant maturation of functional output properties. Alternating phases of AIS plasticity did not occur, and changes in functional output properties were largely justified by AIS elongation. From the third postnatal week up to five months of age, cell growth, AIS elongation, and functional output maturation were marginal. Thus, AIS maturation in M1LV is a continuous process that attunes the functional output of pyramidal neurons and associates with early postnatal development to counterbalance increasing electrical leakage due to cell growth.
Topics: Action Potentials; Age Factors; Animals; Axon Initial Segment; Cell Differentiation; Cells, Cultured; Growth; Models, Neurological; Motor Cortex; Motor Neurons; Neurogenesis; Neuronal Plasticity; Rats
PubMed: 32847128
DOI: 10.3390/ijms21176101 -
NeuroImage Jun 2020Neurocognitive research is pertinent to developing mechanistic models of how humans generate creative thoughts. Such models usually overlook the role of the motor cortex... (Review)
Review
Neurocognitive research is pertinent to developing mechanistic models of how humans generate creative thoughts. Such models usually overlook the role of the motor cortex in creative thinking. The framework of embodied or grounded cognition suggests that creative thoughts (e.g. using a shoe as a hammer, improvising a piano solo) are partially served by simulations of motor activity associated with tools and their use. The major hypothesis stemming from the embodied or grounded account is that, while the motor system is used to execute actions, simulations within this system also support higher-order cognition, creativity included. That is, the cognitive process of generating creative output, not just executing it, is deeply embedded in motor processes. Here, we highlight a collection of neuroimaging research that implicates the motor system in generating creative thoughts, including some evidence for its functionally necessary role in generating creative output. Specifically, the grounded or embodied framework suggests that generating creative output may, in part, rely on motor simulations of possible actions, and that these simulations may by partially implemented in the motor regions themselves. In such cases, action simulations (i.e. reactivating or re-using the motor system), do not result in overt action but instead are used to support higher-order cognitive goals like generating creative uses or improvising.
Topics: Cognition; Creativity; Humans; Motor Cortex
PubMed: 32142883
DOI: 10.1016/j.neuroimage.2020.116697 -
Neurosurgery Clinics of North America Oct 2014Motor cortex stimulation produces significant relief of symptoms in many forms of refractory chronic pain disorders. (Review)
Review
Motor cortex stimulation produces significant relief of symptoms in many forms of refractory chronic pain disorders.
Topics: Brain Mapping; Chronic Pain; Craniotomy; Electric Stimulation Therapy; Humans; Magnetic Resonance Imaging; Motor Cortex; Neuronavigation; Neurosurgical Procedures; Treatment Outcome
PubMed: 25240657
DOI: 10.1016/j.nec.2014.06.004 -
Brain, Behavior and Evolution 2024Felids have evolved a specialized suite of morphological adaptations for obligate carnivory. Although the musculoskeletal anatomy of the Felidae has been studied...
INTRODUCTION
Felids have evolved a specialized suite of morphological adaptations for obligate carnivory. Although the musculoskeletal anatomy of the Felidae has been studied extensively, the comparative neuroanatomy of felids is relatively unexplored. Little is known about how variation in the cerebral anatomy of felids relates to species-specific differences in sociality, hunting strategy, or activity patterns.
METHODS
We quantitatively analyzed neuropil variation in the prefrontal, primary motor, and primary visual cortices of six species of Felidae (Panthera leo, Panthera uncia, Panthera tigris, Panthera leopardus, Acinonyx jubatus, Felis sylvestris domesticus) to investigate relationships with brain size, neuronal cell parameters, and select behavioral and ecological factors. Neuropil is the dense, intricate network of axons, dendrites, and synapses in the brain, playing a critical role in information processing and communication between neurons.
RESULTS
There were significant species and regional differences in neuropil proportions, with African lion, cheetah, and tiger having more neuropil in all three cortical regions in comparison to the other species. Based on regression analyses, we find that the increased neuropil fraction in the prefrontal cortex supports social and behavioral flexibility, while in the primary motor cortex, this facilitates the neural activity needed for hunting movements. Greater neuropil fraction in the primary visual cortex may contribute to visual requirements associated with diel activity patterns.
CONCLUSION
These results provide a cross-species comparison of neuropil fraction variation in the Felidae, particularly the understudied Panthera, and provide evidence for convergence of the neuroanatomy of Panthera and cheetahs.
Topics: Animals; Neuropil; Prefrontal Cortex; Motor Cortex; Species Specificity; Visual Cortex; Felidae; Male; Female
PubMed: 38354714
DOI: 10.1159/000537843 -
Acta Neurochirurgica Jul 2017Navigated transcranial magnetic stimulation (nTMS) is increasingly used for preoperative mapping of motor function, and clinical evidence for its benefit for brain tumor... (Review)
Review
INTRODUCTION
Navigated transcranial magnetic stimulation (nTMS) is increasingly used for preoperative mapping of motor function, and clinical evidence for its benefit for brain tumor patients is accumulating. In respect to language mapping with repetitive nTMS, literature reports have yielded variable results, and it is currently not routinely performed for presurgical language localization. The aim of this project is to define a common protocol for nTMS motor and language mapping to standardize its neurosurgical application and increase its clinical value.
METHODS
The nTMS workshop group, consisting of highly experienced nTMS users with experience of more than 1500 preoperative nTMS examinations, met in Helsinki in January 2016 for thorough discussions of current evidence and personal experiences with the goal to recommend a standardized protocol for neurosurgical applications.
RESULTS
nTMS motor mapping is a reliable and clinically validated tool to identify functional areas belonging to both normal and lesioned primary motor cortex. In contrast, this is less clear for language-eloquent cortical areas identified by nTMS. The user group agreed on a core protocol, which enables comparison of results between centers and has an excellent safety profile. Recommendations for nTMS motor and language mapping protocols and their optimal clinical integration are presented here.
CONCLUSION
At present, the expert panel recommends nTMS motor mapping in routine neurosurgical practice, as it has a sufficient level of evidence supporting its reliability. The panel recommends that nTMS language mapping be used in the framework of clinical studies to continue refinement of its protocol and increase reliability.
Topics: Brain Mapping; Humans; Language; Motor Cortex; Neuronavigation; Transcranial Magnetic Stimulation
PubMed: 28456870
DOI: 10.1007/s00701-017-3187-z -
Brain : a Journal of Neurology Jun 2023
Topics: Humans; Motor Neurons; Motor Cortex
PubMed: 36729767
DOI: 10.1093/brain/awad021 -
Journal of Neurophysiology Apr 2016Changes in the environment require rapid modification or inhibition of ongoing behavior. We used the stop-signal paradigm and intracranial recordings to investigate...
Changes in the environment require rapid modification or inhibition of ongoing behavior. We used the stop-signal paradigm and intracranial recordings to investigate response preparation, inhibition, and monitoring of task-relevant information. Electrocorticographic data were recorded in eight patients with electrodes covering frontal, temporal, and parietal cortex, and time-frequency analysis was used to examine power differences in the beta (13-30 Hz) and high-gamma bands (60-180 Hz). Over motor cortex, beta power decreased, and high-gamma power increased during motor preparation for both go trials (Go) and unsuccessful stops (US). For successful stops (SS), beta increased, and high-gamma was reduced, indexing the cancellation of the prepared response. In the middle frontal gyrus (MFG), stop signals elicited a transient high-gamma increase. The MFG response occurred before the estimated stop-signal reaction time but did not distinguish between SS and US trials, likely signaling attention to the salient stop stimulus. A postresponse high-gamma increase in MFG was stronger for US compared with SS and absent in Go, supporting a role in behavior monitoring. These results provide evidence for differential contributions of frontal subregions to response inhibition, including motor preparation and inhibitory control in motor cortex and cognitive control and action evaluation in lateral prefrontal cortex.
Topics: Adult; Attention; Beta Rhythm; Drug Resistant Epilepsy; Female; Gamma Rhythm; Humans; Male; Motor Cortex; Neural Inhibition; Psychomotor Performance
PubMed: 26864760
DOI: 10.1152/jn.00708.2015 -
Journal of Neuroengineering and... Nov 2019Transcranial Direct Current Stimulation (tDCS) is a non-invasive technique used to modulate neural tissue. Neuromodulation apparently improves cognitive functions in... (Review)
Review
Transcranial Direct Current Stimulation (tDCS) is a non-invasive technique used to modulate neural tissue. Neuromodulation apparently improves cognitive functions in several neurologic diseases treatment and sports performance. In this study, we present a comprehensive, integrative review of tDCS for motor rehabilitation and motor learning in healthy individuals, athletes and multiple neurologic and neuropsychiatric conditions. We also report on neuromodulation mechanisms, main applications, current knowledge including areas such as language, embodied cognition, functional and social aspects, and future directions. We present the use and perspectives of new developments in tDCS technology, namely high-definition tDCS (HD-tDCS) which promises to overcome one of the main tDCS limitation (i.e., low focality) and its application for neurological disease, pain relief, and motor learning/rehabilitation. Finally, we provided information regarding the Transcutaneous Spinal Direct Current Stimulation (tsDCS) in clinical applications, Cerebellar tDCS (ctDCS) and its influence on motor learning, and TMS combined with electroencephalography (EEG) as a tool to evaluate tDCS effects on brain function.
Topics: Athletes; Healthy Volunteers; Humans; Learning; Motor Cortex; Nervous System Diseases; Transcranial Direct Current Stimulation
PubMed: 31730494
DOI: 10.1186/s12984-019-0581-1 -
Journal of Neurophysiology Jul 2017Transcallosal fibers facilitate interhemispheric networks involved in motor tasks. Despite their clinical relevance, interhemispheric motor control systems have not been...
Transcallosal fibers facilitate interhemispheric networks involved in motor tasks. Despite their clinical relevance, interhemispheric motor control systems have not been completely defined in the developing brain. The objective of this study was to examine the developmental profile of transcallosal inhibition in healthy children and adolescents. Nineteen typically developing right-handed participants were recruited. Two transcranial magnetic stimulation (TMS) paradigms assessed transcallosal inhibition: ipsilateral silent periods (iSP) and paired-pulse interhemispheric inhibition (IHI). TMS was applied to the motor hotspot of the first dorsal interosseous muscle. Resting motor threshold (RMT), iSP latency, duration and suppression strength, and paired-pulse IHI were measured from both hemispheres. The Purdue Pegboard Test assessed unimanual motor function. Hemispheric differences were evident for RMT and iSP latency and suppression strength, where the left hemisphere had a lower RMT, prolonged latency, and greater suppression strength. iSP duration showed hemispheric symmetry. RMT and iSP latency decreased with age, whereas iSP suppression strength increased. Girls showed shorter iSP latency. Children typically displayed IHI, although hemispheric differences were observed. iSP suppression strength was uniquely associated with IHI within individuals. iSP duration correlated with motor performance. TMS can characterize transcallosal inhibition in normal children and adolescents with effects of age, directionality, sex, and motor performance. Establishing this developmental profile of interhemispheric interactions may advance understanding and therapeutic strategies for pediatric motor disorders such as cerebral palsy. Here we demonstrate that transcranial magnetic stimulation can characterize transcallosal inhibition in normal children and adolescents with effects of age, directionality, handedness, and motor performance. Interestingly, we also demonstrated sex effects, possibly related to the differing developmental profiles of boys and girls. Establishing this developmental profile of interhemispheric interactions may advance understanding and therapeutic strategies for pediatric motor disorders such as cerebral palsy.
Topics: Adolescent; Child; Corpus Callosum; Female; Functional Laterality; Humans; Male; Motor Cortex; Neural Inhibition; Reaction Time; Transcranial Magnetic Stimulation
PubMed: 28381485
DOI: 10.1152/jn.00076.2017