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BioRxiv : the Preprint Server For... Jun 2024Stereoelectroencephalography (sEEG) is a mesoscale intracranial monitoring method which records from the brain volumetrically with depth electrodes. Implementation of...
INTRODUCTION
Stereoelectroencephalography (sEEG) is a mesoscale intracranial monitoring method which records from the brain volumetrically with depth electrodes. Implementation of sEEG in BCI has not been well-described across a diverse patient cohort.
METHODS
Across eighteen subjects, channels with high frequency broadband (HFB, 65-115Hz) power increases during hand, tongue, or foot movements during a motor screening task were provided real-time feedback based on these HFB power changes to control a cursor on a screen.
RESULTS
Seventeen subjects established successful control of the overt motor BCI, but only nine were able to control imagery BCI with 80% accuracy. In successful imagery BCI, HFB power in the two target conditions separated into distinct subpopulations, which appear to engage unique subnetworks of the motor cortex compared to cued movement or imagery alone.
CONCLUSION
sEEG-based motor BCI utilizing overt movement and kinesthetic imagery is robust across patient ages and cortical regions with substantial differences in learning proficiency between real or imagined movement.
PubMed: 38915599
DOI: 10.1101/2024.06.12.598257 -
BioRxiv : the Preprint Server For... Jun 2024Our understanding of how visual cortex neural processes mature during infancy and toddlerhood is limited. Using magnetoencephalography (MEG), the present study...
UNLABELLED
Our understanding of how visual cortex neural processes mature during infancy and toddlerhood is limited. Using magnetoencephalography (MEG), the present study investigated the development of visual evoked responses (VERs) in both cross-sectional and longitudinal samples of infants and toddlers 2 months to 3 years. Brain space analyses focused on N1m and P1m latency, as well as the N1m-to-P1m amplitude. Associations between VER measures and developmental quotient (DQ) scores in the cognitive/visual and fine motor domains were also examined. Results showed a nonlinear decrease in N1m and P1m latency as a function of age, characterized by rapid changes followed by slower progression, with the N1m latency plateauing at 6-7 months and the P1m latency plateauing at 8-9 months. The N1m-to-P1m amplitude also exhibited a non-linear decrease, with strong responses observed in younger infants (∼2-3 months) and then a gradual decline. Associations between N1m and P1m latency and fine motor DQ scores were observed, suggesting that infants with faster visual processing may be better equipped to perform fine motor tasks. The present findings advance our understanding of the maturation of the infant visual system and highlight the relationship between the maturation of visual system and fine motor skills.
HIGHLIGHTS
The infant N1m and P1m latency shows a nonlinear decrease.N1m latency decreases precede P1m latency decreases.N1m-to-P1m amplitude shows a nonlinear decrease, with stronger responses in younger than older infants.N1m and P1m latency are associated with fine motor DQ.
PubMed: 38915536
DOI: 10.1101/2024.06.11.598480 -
Journal of Neuroengineering and... Jun 2024Repeated transcranial magnetic stimulation (rTMS) could induce alterations in cortical excitability and promote neuroplasticity. To precisely quantify these effects,... (Meta-Analysis)
Meta-Analysis Review
Impact of repetitive transcranial magnetic stimulation on cortical activity: a systematic review and meta-analysis utilizing functional near-infrared spectroscopy evaluation.
BACKGROUND
Repeated transcranial magnetic stimulation (rTMS) could induce alterations in cortical excitability and promote neuroplasticity. To precisely quantify these effects, functional near-infrared spectroscopy (fNIRS), an optical neuroimaging modality adept at detecting changes in cortical hemodynamic responses, has been employed concurrently alongside rTMS to measure and tailor the impact of diverse rTMS protocols on the brain cortex.
OBJECTIVE
This systematic review and meta-analysis aimed to elucidate the effects of rTMS on cortical hemodynamic responses over the primary motor cortex (M1) as detected by fNIRS.
METHODS
Original articles that utilized rTMS to stimulate the M1 cortex in combination with fNIRS for the assessment of cortical activity were systematically searched across the PubMed, Embase, and Scopus databases. The search encompassed records from the inception of these databases up until April, 2024. The assessment for risk of bias was also conducted. A meta-analysis was also conducted in studies with extractable raw data.
RESULTS
Among 312 studies, 14 articles were eligible for qualitative review. 7 studies were eligible for meta-analysis. A variety of rTMS protocols was employed on M1 cortex. In inhibitory rTMS, multiple studies observed a reduction in the concentration of oxygenated hemoglobin [HbO] at the ipsilateral M1, contrasted by an elevation at the contralateral M1. Meta-analysis also corroborated this consistent trend. Nevertheless, certain investigations unveiled diminished [HbO] in bilateral M1. Several studies also depicted intricate inhibitory or excitatory interplay among distinct cortical regions.
CONCLUSION
Diverse rTMS protocols led to varied patterns of cortical activity detected by fNIRS. Meta-analysis revealed a trend of increasing [HbO] in the contralateral cortices and decreasing [HbO] in the ipsilateral cortices following low frequency inhibitory rTMS. However, due to the heterogeneity between studies, further research is necessary to comprehensively understand rTMS-induced alterations in brain activity.
Topics: Transcranial Magnetic Stimulation; Spectroscopy, Near-Infrared; Humans; Motor Cortex
PubMed: 38915003
DOI: 10.1186/s12984-024-01407-9 -
Journal of Neuroscience Methods Jun 2024
PubMed: 38914375
DOI: 10.1016/j.jneumeth.2024.110208 -
NeuroImage Jun 2024Due to a high degree of symptom overlap in the early stages, with movement disorders predominating, Parkinson's disease (PD) and multiple system atrophy (MSA) may...
Due to a high degree of symptom overlap in the early stages, with movement disorders predominating, Parkinson's disease (PD) and multiple system atrophy (MSA) may exhibit a similar decline in motor areas, yet they differ in their spread throughout the brain, ultimately resulting in two distinct diseases. Drawing upon neuroimaging analyses and altered motor cortex excitability, potential diffusion mechanisms were delved into, and comparisons of correlations across distinct disease groups were conducted in a bid to uncover significant pathological disparities. We recruited thirty-five PD, thirty-seven MSA, and twenty-eight matched controls to conduct clinical assessments, electromyographic recording, and magnetic resonance imaging scanning during the "on medication" state. Patients with neurodegeneration displayed a widespread decrease in electrophysiology in bilateral M1. Brain function in early PD was still in the self-compensatory phase and there was no significant change. MSA patients demonstrated an increase in intra-hemispheric function coupled with a decrease in diffusivity, indicating a reduction in the spread of neural signals. The level of resting motor threshold in healthy aged showed broad correlations with both clinical manifestations and brain circuits related to left M1, which was absent in disease states. Besides, ICF exhibited distinct correlations with functional connections between right M1 and left middle temporal gyrus in all groups. The present study identified subtle differences in the functioning of PD and MSA related to bilateral M1. By combining clinical information, cortical excitability, and neuroimaging intuitively, we attempt to bring light on the potential mechanisms that may underlie the development of neurodegenerative disease.
PubMed: 38914210
DOI: 10.1016/j.neuroimage.2024.120701 -
The International Journal of... Jun 2024Transcranial direct current stimulation (tDCS) has been used with increasing frequency as a therapeutic tool to alleviate clinical symptoms of obsessive... (Review)
Review
Transcranial direct current stimulation (tDCS) has been used with increasing frequency as a therapeutic tool to alleviate clinical symptoms of obsessive compulsive-disorder (OCD). However, little is known about the effects of tDCS on neurocognitive functioning among OCD patients. The aim of this review was to provide a comprehensive overview of the literature examining the effects of tDCS on specific neurocognitive functions in OCD. A literature search following PRISMA guidelines was conducted on the following databases: PubMed, PsycINFO, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), the Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Web of Science. The search yielded 4 results: one randomized, sham-controlled study (20 patients), one randomized, controlled, partial crossover trial (12 patients), one open-label study (5 patients), and one randomized, double-blind, sham-controlled, parallel-group trial (37 patients). A total of 51 patients received active tDCS with some diversity in electrode montages targeting the dorsolateral prefrontal cortex, the pre-supplementary motor area, or the orbitofrontal cortex. tDCS was associated with improved decision-making in study 1, enhanced attentional monitoring and response inhibition in study 2, improved executive and inhibitory control in study 3, and reduced attentional bias and improved response inhibition and working memory in study 4. Limitations of this review include its small sample, the absence of a sham group in half of the studies, and the heterogeneity in tDCS parameters. These preliminary results highlight the need for future testing in randomized, sham-controlled trials to examine whether and how tDCS induces relevant cognitive benefits in OCD.
PubMed: 38913323
DOI: 10.1080/00207454.2024.2371303 -
Molecular Pain Jun 2024Pain and anxiety are two common and undertreated non-motor symptoms in Parkinson's disease (PD), which affect the life quality of PD patients, and the underlying...
Pain and anxiety are two common and undertreated non-motor symptoms in Parkinson's disease (PD), which affect the life quality of PD patients, and the underlying mechanisms remain unclear. As an important subtype of adenylyl cyclases (ACs), adenylyl cyclase subtype 1 (AC1) is critical for the induction of cortical long-term potentiation (LTP) and injury induced synaptic potentiation in the cortical areas including anterior cingulate cortex (ACC) and insular cortex (IC). Genetic deletion of AC1 or pharmacological inhibition of AC1 improved chronic pain and anxiety in different animal models. In this study, we proved the motor deficit, pain, and anxiety symptoms of PD in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice model. As a lead candidate AC1 inhibitor, oral administration (1 dose and 7 doses) of NB001 (20 and 40 mg/kg) showed significant analgesic effect in MPTP-treated mice, and the anxiety behavior was also reduced (40 mg/kg). By using genetic knockout mice, we found that AC1 knockout mice showed reduced pain and anxiety symptoms after MPTP administration, but not AC8 knockout mice. In summary, genetic deletion of AC1 or pharmacological inhibition of AC1 improved pain and anxiety symptoms in PD model mice, but didn't affect motor function. These results suggest that NB001 is a potential drug for the treatment of pain and anxiety symptoms in PD patients by inhibiting AC1 target.
PubMed: 38912637
DOI: 10.1177/17448069241266683 -
Cyborg and Bionic Systems (Washington,... 2024Complementary to brain-computer interface (BCI) based on motor imagery (MI) task, sensory imagery (SI) task provides a way for BCI construction using brain activity from...
Complementary to brain-computer interface (BCI) based on motor imagery (MI) task, sensory imagery (SI) task provides a way for BCI construction using brain activity from somatosensory cortex. The underlying neurophysiological correlation between SI and MI was unclear and difficult to measure through behavior recording. In this study, we investigated the underlying neurodynamic of motor/tactile imagery and tactile sensation tasks through a high-density electroencephalogram (EEG) recording, and EEG source imaging was used to systematically explore the cortical activation differences and correlations between the tasks. In the experiment, participants were instructed to perform the left and right hand tasks in MI paradigm, sensory stimulation (SS) paradigm and SI paradigm. The statistical results demonstrated that the imagined MI and SI tasks differed from each other within ipsilateral sensorimotor scouts, frontal and right temporal areas in α bands, whereas real SS and imagined SI showed a similar activation pattern. The similarity between SS and SI may provide a way to train the BCI system, while the difference between MI and SI may provide a way to integrate the discriminative information between them to enhance BCI performance. The combination of the tasks and its underlying neurodynamic would provide a new approach for BCI designation for a wider application. BCI studies concentrate on the hybrid decoding method combining MI or SI with SS, but the underlining neurophysiological correlates between them were unclear. MI and SI differed from each other within the ipsilateral sensorimotor cortex in alpha bands. This is a first study to investigate the neurophysiological relationship between MI and SI through an EEG source imaging approach from high-density EEG recording.
PubMed: 38912322
DOI: 10.34133/cbsystems.0118 -
Cureus Jun 2024Malformations of cortical development (MCD) are a group of disorders affecting the normal development of the human cortex and are significant causes of delay in...
Malformations of cortical development (MCD) are a group of disorders affecting the normal development of the human cortex and are significant causes of delay in psychomotor development and epilepsy in children. Lissencephaly (smooth brain) forms a major group of brain malformations. Microtubules help in the migration of neuronal cells. Defect in tubulin gene alpha-tubulin (TUBA), beta-tubulin (TUBB), and gamma-tubulin (TUBG) leads to defective neuronal migration. This group of disorders is termed as "tubulinopathies." The important genes implicated in causing lissencephaly are LIS1, XLIS, and TUBA1A gene. Recently, a mutation in the TUBG1 gene is associated with it. Here, we report a one-and-a-half-year-old girl with global developmental delay, microcephaly, infantile-onset epilepsy, epileptic spasms, dysmorphism, and motor signs. There was no significant birth history. Neuroimaging (MRI) showed a broad thick gyri and a decreased number of sulci suggestive of lissencephaly/pachygyria spectrum. There was dilatation of the ventricles, and no grey matter heterotopia was noted. Sleep EEG showed multifocal epileptiform discharges. The child was treated with multiple anti-seizure medicines (ASMs). A genetic test, whole exome sequencing, was done to determine the etiology of MCD. A heterozygous missense variation in exon 6 of the TUBG1 gene was identified and reported as a "variant of unknown significance." Still, because the genotype matched with the clinical phenotype of the patient, it was considered clinically significant. Therefore, a complete diagnosis of TUBG1 mutation-associated cortical malformation (lissencephaly/pachygyria) with microcephaly and early-onset epilepsy was established. TUBG1 mutation is de novo in most cases, but parental testing is recommended. The parents of such patients need to be counseled about the need for prenatal testing and the risk of the disease to siblings. The overall prognosis in such cases is poor because of refractory seizures, physical limitations, and intellectual disability.
PubMed: 38912084
DOI: 10.7759/cureus.62749 -
Frontiers in Human Neuroscience 2024Repetitive somatosensory stimulation (RSS) is a conventional approach to modulate the neural states of both the primary somatosensory cortex (S1) and the primary motor...
INTRODUCTION
Repetitive somatosensory stimulation (RSS) is a conventional approach to modulate the neural states of both the primary somatosensory cortex (S1) and the primary motor cortex (M1). However, the impact of RSS on skill acquisition and retention in sensorimotor adaptation remains debated. This study aimed to investigate whether whole-hand water flow (WF), a unique RSS-induced M1 disinhibition, influences sensorimotor adaptation by examining the hypothesis that whole-hand WF leads to M1 disinhibition; thereby, enhancing motor memory retention.
METHODS
Sixty-eight young healthy participants were randomly allocated to three groups based on the preconditioning received before motor learning: control, whole-hand water immersion (WI), and whole-hand WF. The experimental protocol for all the participants spanned two consecutive days. On the initial day (day 1), baseline transcranial magnetic stimulation (TMS) assessments (T0) were executed before any preconditioning. Subsequently, each group underwent their respective 30 min preconditioning protocol. To ascertain the influence of each preconditioning on the excitability of the M1, subsequent TMS assessments were conducted (T1). Following this, all participants engaged in the motor learning (ML) of a visuomotor tracking task, wherein they were instructed to align a cursor with a target trajectory by modulating the pinch force. Upon completion of the ML session, final TMS assessments (T2) were conducted. All participants were required to perform the same motor learning 24 h later on day 2.
RESULTS
The results revealed that whole-hand WF did not significantly influence skill acquisition during sensorimotor adaptation, although it did reduce intracortical inhibition. This phenomenon is consistent with the idea that S1, rather than M1, is involved in skill acquisition during the early stages of sensorimotor adaptation. Moreover, memory retention 24 h after skill acquisition did not differ significantly across the three groups, challenging our initial hypothesis that whole-hand WF enhances memory retention throughout sensorimotor adaptation. This could be due to the inability of whole-hand WF to alter sensorimotor connectivity and integration, as well as the nature of the plastic response elicited by the preconditioning.
DISCUSSION
In conclusion, these findings suggest that although whole-hand WF attenuates intracortical inhibition, it does not modulate skill acquisition or motor memory retention during sensorimotor adaptation.
PubMed: 38911224
DOI: 10.3389/fnhum.2024.1398164