Intracortical neural interfaces directly connect brain neurons with external devices to achieve high temporal resolution and spatially precise sampling of neural activity.When applied to freely moving animals,this tec...Intracortical neural interfaces directly connect brain neurons with external devices to achieve high temporal resolution and spatially precise sampling of neural activity.When applied to freely moving animals,this technology provides in-depth insight into the underlying neural mechanisms for their movement and cognition in real-world scenarios.However,the application of implanted devices in freely moving animals is limited by restrictions on their behavioral freedom and physiologic impact.In this paper,four technological directions for ideal implantable neural interface devices are analyzed:higher spatial density,improved biocompatibility,enhanced multimodal detection of electrical/neurotransmitter signals,and more effective neural modulation.Finally,we discuss how these technological developments have been applied to freely moving animals to provide better insight into neuroscience and clinical medicine.展开更多
BACKGROUND In most elderly patients with intertrochanteric fractures,satisfactory fracture reduction can be achieved by closed reduction using a traction table.However,intertrochanteric fractures cannot achieve satisf...BACKGROUND In most elderly patients with intertrochanteric fractures,satisfactory fracture reduction can be achieved by closed reduction using a traction table.However,intertrochanteric fractures cannot achieve satisfactory reduction in a few patients,which is called irreducible intertrochanteric fractures.Especially for type 31A3 irreducible intertrochanteric fractures,limited open reduction of the broken end with different intraoperative reduction methods is required to achieve satisfactory reduction and fixation.AIM To discuss clinical efficacy of intracortical screw insertion plus limited open reduction in type 31A3 irreducible intertrochanteric fractures in the elderly.METHODS A retrospective analysis was performed on 23 elderly patients with type 31A3 irreducible intertrochanteric fractures(12 males and 11 females,aged 65-89-yearsold)who received treatment at the orthopedics department.After type 31A3 irreducible intertrochanteric fractures were confirmed by intraoperative C-arm,all of these cases received intracortical screw insertion plus limited open reduction in the broken end with intramedullary screw internal fixation.The basic information of surgery,reduction effects,and functional recovery scores of the hip joint were assessed.RESULTS All patients were followed up for 13.8 mo on average.The operation time was 53.8±13.6 min(40-95 min).The intraoperative blood loss was 218.5±28.6 mL(170-320 mL).The average number of intraoperative X-rays was 22.8±4.6(18-33).The average time to fracture union was 4.8±0.7 mo.The reduction effect was assessed using Kim’s fracture reduction evaluation.Twenty cases achieved grade I fracture reduction and three cases grade II fracture reduction.All of them achieved excellent or good fracture reduction.Upon the last follow-up,the functional recovery scores score was 83.6±9.8,which was not significantly different from the functional recovery scores score(84.8±10.7)before the fracture(t=0.397,P=0.694).CONCLUSION With careful preoperative preparation,intracortical screw insertion plus limited open reduction contributed to high-quality fracture reduction and fixation.Good clinical outcomes were achieved without increasing operation time and intraoperative blood loss.展开更多
To understand the complex dynamics of neural activity in the brain across various temporal and spatial scales,it is crucial to record intracortical multimodal neural activity by combining electrophysiological recordin...To understand the complex dynamics of neural activity in the brain across various temporal and spatial scales,it is crucial to record intracortical multimodal neural activity by combining electrophysiological recording and calcium imaging techniques.This poses significant constraints on the geometrical,mechanical,and optical properties of the electrodes.Here,transparent flexible graphene–ITO-based neural microelectrodes with small feature sizes are developed and validated for simultaneous electrophysiology recording and calcium imaging in the hippocampus of freely moving mice.A micro-etching technique and an oxygen plasma pre-treating method are introduced to facilitate large-area graphene transfer and establish stable low-impedance contacts between graphene and metals,leading to the batch production of high-quality microelectrodes with interconnect widths of 10μm and recording sites diameters of 20μm.These electrodes exhibit appropriate impedance and sufficient transparency in the field of view,enabling simultaneous recording of intracortical local field potentials and even action potentials along with calcium imaging in freely moving mice.Both types of electrophysiological signals are found to correlate with calcium activity.This proof-of-concept work demonstrates that transparent flexible graphene–ITO-based neural microelectrodes are promising tools for multimodal neuroscience research.展开更多
Extracellular matrix(ECM)-based implantable neural electrodes(NEs)were achieved using a microfabrication strategy on naturalsubstrate-based organic materials.The ECM-based design minimized the introduction of non-natu...Extracellular matrix(ECM)-based implantable neural electrodes(NEs)were achieved using a microfabrication strategy on naturalsubstrate-based organic materials.The ECM-based design minimized the introduction of non-natural products into the brain.Further,it rendered the implants sufficiently rigid for penetration into the target brain region and allowed them subsequently to soften to match the elastic modulus of brain tissue upon exposure to physiological conditions,thereby reducing inflammatory strain fields in the tissue.Preliminary studies suggested that ECM-NEs produce a reduced inflammatory response compared with inorganic rigid and flexible approaches.In vivo intracortical recordings from the rat motor cortex illustrate one mode of use for these ECM-NEs.展开更多
Along with the flourishing of brain-computer interface technology,the brain-to-brain information transmission between different organisms has received high attention in recent years.However,specific information transm...Along with the flourishing of brain-computer interface technology,the brain-to-brain information transmission between different organisms has received high attention in recent years.However,specific information transmission mode and implementation technology need to be further studied.In this paper,we constructed a brain-to-brain information transmission system between pigeons based on the neural information decoding and electrical stimulation encoding technologies.Our system consists of three parts:(1)the“perception pigeon”learns to distinguish different visual stimuli with two discrepant frequencies,(2)the computer decodes the stimuli based on the neural signals recorded from the“perception pigeon”through a frequency identification algorithm(neural information decoding)and encodes them into different kinds of electrical pulses,(3)the“action pigeon”receives the Intracortical Microstimulation(ICMS)and executes corresponding key-pecking actions through discriminative learning(electrical stimulation encoding).The experimental results show that our brain-to-brain system achieves information transmission from perception to action between two pigeons with the average accuracy of about 72%.Our study verifies the feasibility of information transmission between inter-brain based on neural information decoding and ICMS encoding,providing important technical methods and experimental program references for the development of brain-to-brain communication technology.展开更多
To explore whether experiencing inflammatory pain has an impact upon intracortical synaptic organization, the planar multi-electrode array （MEA） technique and 2-dimensional current source density （2D-CSD） imaging ...To explore whether experiencing inflammatory pain has an impact upon intracortical synaptic organization, the planar multi-electrode array （MEA） technique and 2-dimensional current source density （2D-CSD） imaging were used in slice preparations of the anterior cingulate cortex （ACC） from rats. Synaptic activity across different layers of the ACC was evoked by deep layer stimulation through one electrode. The layer-localization of both local field potentials （LFPs） and the spread of current sink calculated by 2D-CSD analysis was characterized pharmacologically. Moreover, the induction of long-term potentiation （LTP） and changes in LTP magnitude were also evaluated. We found that under naive conditions, the current sink was initially generated in layer Ⅵ, then spread to layer Ⅴ and finally confined to layers Ⅱ-Ⅲ. This spatial pattern of current sink movement typically reflected changes in depolarized sites from deep layers （Ⅴ-Ⅵ） to superficial layers （Ⅱ-Ⅲ） where intra- and extra- cortical inputs terminate. In the ACC slices from rats in an inflamed state （for 2 h） caused by intraplantar bee-venom injection, the spatial profile of intra-ACC synaptic organization was significantly changed,showing an enlarged current sink distribution and a leftward shift of the stimulus-response curves relative to the naive and saline controls. The change was more distinct in the superficial layers （Ⅱ-Ⅲ） than in the deep site. In terms of temporal properties, the rate of LTP induction was significantly increased in layers Ⅱ-Ⅲ by inflammatory pain. However, the magnitude of LTP was not significantly enhanced by this treatment. Taken together, these results show that inflammatory pain results in distinct spatial and temporal plasticity of synaptic organization in the ACC, which may lead to altered synaptic transmission and modulation.展开更多
The effects of exercise on decision-making performance have been studied using a wide variety of cognitive tasks and exercise interventions. Although the current literature supports a beneficial influence of acute exe...The effects of exercise on decision-making performance have been studied using a wide variety of cognitive tasks and exercise interventions. Although the current literature supports a beneficial influence of acute exercise on cognitive performance, the mechanisms underlying this phenomenon have not yet been elucidated. We review studies that used single-pulse transcranial magnetic stimulation （TMS） to probe the excitability of motor structures during whole-body exercise and present a framework to account for the facilitating effects of acute exercise on motor processes. Recent results suggest that, even in the absence of fatigue, the increase in corticospinal excitability classically reported during submaximal and exhausting exercises may be accompanied by a reduction in intracortical inhibition. We propose that reduced intracortical inhibition elicits an adaptive central mechanism that counteracts the progressive reduction in muscle responsiveness caused by peripheral fatigue. Such a reduction would render the motor cortex more sensitive to upstream influences, thus causing increased corticospinal excitability. Furthermore, reduction of intracortical inhibition may account for the more efficient descending drive and for the improvement of reaction time performance during exercise. The adaptive modulation in intracortical inhibition could be implemented through a general increase in reticular activation that would further account for enhanced sensory sensitivity.展开更多
The authors regret that due to an oversight,the online version of Fig.5 is missing the sign,here is the correct Fig.5 and its caption.Fig.5:(A)Short interval intracortical inhibition(SICI)and(B)Long interval intracort...The authors regret that due to an oversight,the online version of Fig.5 is missing the sign,here is the correct Fig.5 and its caption.Fig.5:(A)Short interval intracortical inhibition(SICI)and(B)Long interval intracortical inhibition(LICI)in active and sham groups(Median,interquartile range,MEP peak to peak amplitude conditioned/test)of hemiplegic CP patients at baseline(pre)and after intervention.展开更多
Neural damage has been a great challenge to the medical field for a very long time.The emergence of brain–computer interfaces(BCIs)offered a new possibility to enhance the activity of daily living and provide a new f...Neural damage has been a great challenge to the medical field for a very long time.The emergence of brain–computer interfaces(BCIs)offered a new possibility to enhance the activity of daily living and provide a new formation of entertainment for those with disabilities.Intracortical BCIs,which require the implantation of microelectrodes,can receive neuronal signals with a high spatial and temporal resolution from the individual’s cortex.When BCI decoded cortical signals and mapped them to external devices,it displayed the ability not only to replace part of the human motor function but also to help individuals restore certain neurological functions.In this review,we focus on human intracortical BCI research using microelectrode arrays and summarize the main directions and the latest results in this field.In general,we found that intracortical BCI research based on motor neuroprosthetics and functional electrical stimulation have already achieved some simple functional replacement and treatment of motor function.Pioneering work in the posterior parietal cortex has given us a glimpse of the potential that intracortical BCIs have to control external devices and receive various sensory information.展开更多
基金sponsored by the National Natural Science Foundation of China(62121003,T2293730,T2293731,61960206012,62333020,and 62171434)the National Key Research and Development Program of China(2022YFC2402501 and 2022YFB3205602)the Major Program of Scientific and Technical Innovation 2030(2021ZD02016030)。
文摘Intracortical neural interfaces directly connect brain neurons with external devices to achieve high temporal resolution and spatially precise sampling of neural activity.When applied to freely moving animals,this technology provides in-depth insight into the underlying neural mechanisms for their movement and cognition in real-world scenarios.However,the application of implanted devices in freely moving animals is limited by restrictions on their behavioral freedom and physiologic impact.In this paper,four technological directions for ideal implantable neural interface devices are analyzed:higher spatial density,improved biocompatibility,enhanced multimodal detection of electrical/neurotransmitter signals,and more effective neural modulation.Finally,we discuss how these technological developments have been applied to freely moving animals to provide better insight into neuroscience and clinical medicine.
基金by the National Natural Science Foundation of China,No.81902206.
文摘BACKGROUND In most elderly patients with intertrochanteric fractures,satisfactory fracture reduction can be achieved by closed reduction using a traction table.However,intertrochanteric fractures cannot achieve satisfactory reduction in a few patients,which is called irreducible intertrochanteric fractures.Especially for type 31A3 irreducible intertrochanteric fractures,limited open reduction of the broken end with different intraoperative reduction methods is required to achieve satisfactory reduction and fixation.AIM To discuss clinical efficacy of intracortical screw insertion plus limited open reduction in type 31A3 irreducible intertrochanteric fractures in the elderly.METHODS A retrospective analysis was performed on 23 elderly patients with type 31A3 irreducible intertrochanteric fractures(12 males and 11 females,aged 65-89-yearsold)who received treatment at the orthopedics department.After type 31A3 irreducible intertrochanteric fractures were confirmed by intraoperative C-arm,all of these cases received intracortical screw insertion plus limited open reduction in the broken end with intramedullary screw internal fixation.The basic information of surgery,reduction effects,and functional recovery scores of the hip joint were assessed.RESULTS All patients were followed up for 13.8 mo on average.The operation time was 53.8±13.6 min(40-95 min).The intraoperative blood loss was 218.5±28.6 mL(170-320 mL).The average number of intraoperative X-rays was 22.8±4.6(18-33).The average time to fracture union was 4.8±0.7 mo.The reduction effect was assessed using Kim’s fracture reduction evaluation.Twenty cases achieved grade I fracture reduction and three cases grade II fracture reduction.All of them achieved excellent or good fracture reduction.Upon the last follow-up,the functional recovery scores score was 83.6±9.8,which was not significantly different from the functional recovery scores score(84.8±10.7)before the fracture(t=0.397,P=0.694).CONCLUSION With careful preoperative preparation,intracortical screw insertion plus limited open reduction contributed to high-quality fracture reduction and fixation.Good clinical outcomes were achieved without increasing operation time and intraoperative blood loss.
基金support of the National Key R&D Program of China(2022YFF1202303 and 2023YFF1203702)NSFC-Guangdong Joint Fund(U20A6005)+2 种基金the National Natural Science Foundation of China(62071447)STI2030-Major Projects(2021ZD0200100)the Science and Technology Innovation Committee of Shenzhen Municipality(JCYJ20220818101611024).
文摘To understand the complex dynamics of neural activity in the brain across various temporal and spatial scales,it is crucial to record intracortical multimodal neural activity by combining electrophysiological recording and calcium imaging techniques.This poses significant constraints on the geometrical,mechanical,and optical properties of the electrodes.Here,transparent flexible graphene–ITO-based neural microelectrodes with small feature sizes are developed and validated for simultaneous electrophysiology recording and calcium imaging in the hippocampus of freely moving mice.A micro-etching technique and an oxygen plasma pre-treating method are introduced to facilitate large-area graphene transfer and establish stable low-impedance contacts between graphene and metals,leading to the batch production of high-quality microelectrodes with interconnect widths of 10μm and recording sites diameters of 20μm.These electrodes exhibit appropriate impedance and sufficient transparency in the field of view,enabling simultaneous recording of intracortical local field potentials and even action potentials along with calcium imaging in freely moving mice.Both types of electrophysiological signals are found to correlate with calcium activity.This proof-of-concept work demonstrates that transparent flexible graphene–ITO-based neural microelectrodes are promising tools for multimodal neuroscience research.
基金This work was funded by the Defense Advanced Research Projects Agency(DARPA)MTO under the auspices of Dr.Jack Judy through the Space and Naval Warfare Systems Center,Pacific Grant/Contract No.N66001-11-1-4014.
文摘Extracellular matrix(ECM)-based implantable neural electrodes(NEs)were achieved using a microfabrication strategy on naturalsubstrate-based organic materials.The ECM-based design minimized the introduction of non-natural products into the brain.Further,it rendered the implants sufficiently rigid for penetration into the target brain region and allowed them subsequently to soften to match the elastic modulus of brain tissue upon exposure to physiological conditions,thereby reducing inflammatory strain fields in the tissue.Preliminary studies suggested that ECM-NEs produce a reduced inflammatory response compared with inorganic rigid and flexible approaches.In vivo intracortical recordings from the rat motor cortex illustrate one mode of use for these ECM-NEs.
基金supported by the National Natural Science Foundation of China(62301496)the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(GZC20232447)+1 种基金the Program for Science and Technology of Henan Province of China(242300421411)the Key Scientific and Technological Projects of Henan Province(232102210072,232102210098).
文摘Along with the flourishing of brain-computer interface technology,the brain-to-brain information transmission between different organisms has received high attention in recent years.However,specific information transmission mode and implementation technology need to be further studied.In this paper,we constructed a brain-to-brain information transmission system between pigeons based on the neural information decoding and electrical stimulation encoding technologies.Our system consists of three parts:(1)the“perception pigeon”learns to distinguish different visual stimuli with two discrepant frequencies,(2)the computer decodes the stimuli based on the neural signals recorded from the“perception pigeon”through a frequency identification algorithm(neural information decoding)and encodes them into different kinds of electrical pulses,(3)the“action pigeon”receives the Intracortical Microstimulation(ICMS)and executes corresponding key-pecking actions through discriminative learning(electrical stimulation encoding).The experimental results show that our brain-to-brain system achieves information transmission from perception to action between two pigeons with the average accuracy of about 72%.Our study verifies the feasibility of information transmission between inter-brain based on neural information decoding and ICMS encoding,providing important technical methods and experimental program references for the development of brain-to-brain communication technology.
基金supported by grants from the National Basic Research Development ProgramMinistry of Science and Technology of China(2013CB835100+3 种基金2013BAI04B04)the National Natural Science Foundation of China(8107089981171049)a Military Project of China(AWS12J004)
文摘To explore whether experiencing inflammatory pain has an impact upon intracortical synaptic organization, the planar multi-electrode array （MEA） technique and 2-dimensional current source density （2D-CSD） imaging were used in slice preparations of the anterior cingulate cortex （ACC） from rats. Synaptic activity across different layers of the ACC was evoked by deep layer stimulation through one electrode. The layer-localization of both local field potentials （LFPs） and the spread of current sink calculated by 2D-CSD analysis was characterized pharmacologically. Moreover, the induction of long-term potentiation （LTP） and changes in LTP magnitude were also evaluated. We found that under naive conditions, the current sink was initially generated in layer Ⅵ, then spread to layer Ⅴ and finally confined to layers Ⅱ-Ⅲ. This spatial pattern of current sink movement typically reflected changes in depolarized sites from deep layers （Ⅴ-Ⅵ） to superficial layers （Ⅱ-Ⅲ） where intra- and extra- cortical inputs terminate. In the ACC slices from rats in an inflamed state （for 2 h） caused by intraplantar bee-venom injection, the spatial profile of intra-ACC synaptic organization was significantly changed,showing an enlarged current sink distribution and a leftward shift of the stimulus-response curves relative to the naive and saline controls. The change was more distinct in the superficial layers （Ⅱ-Ⅲ） than in the deep site. In terms of temporal properties, the rate of LTP induction was significantly increased in layers Ⅱ-Ⅲ by inflammatory pain. However, the magnitude of LTP was not significantly enhanced by this treatment. Taken together, these results show that inflammatory pain results in distinct spatial and temporal plasticity of synaptic organization in the ACC, which may lead to altered synaptic transmission and modulation.
文摘The effects of exercise on decision-making performance have been studied using a wide variety of cognitive tasks and exercise interventions. Although the current literature supports a beneficial influence of acute exercise on cognitive performance, the mechanisms underlying this phenomenon have not yet been elucidated. We review studies that used single-pulse transcranial magnetic stimulation （TMS） to probe the excitability of motor structures during whole-body exercise and present a framework to account for the facilitating effects of acute exercise on motor processes. Recent results suggest that, even in the absence of fatigue, the increase in corticospinal excitability classically reported during submaximal and exhausting exercises may be accompanied by a reduction in intracortical inhibition. We propose that reduced intracortical inhibition elicits an adaptive central mechanism that counteracts the progressive reduction in muscle responsiveness caused by peripheral fatigue. Such a reduction would render the motor cortex more sensitive to upstream influences, thus causing increased corticospinal excitability. Furthermore, reduction of intracortical inhibition may account for the more efficient descending drive and for the improvement of reaction time performance during exercise. The adaptive modulation in intracortical inhibition could be implemented through a general increase in reticular activation that would further account for enhanced sensory sensitivity.
文摘The authors regret that due to an oversight,the online version of Fig.5 is missing the sign,here is the correct Fig.5 and its caption.Fig.5:(A)Short interval intracortical inhibition(SICI)and(B)Long interval intracortical inhibition(LICI)in active and sham groups(Median,interquartile range,MEP peak to peak amplitude conditioned/test)of hemiplegic CP patients at baseline(pre)and after intervention.
基金supported by National key R&D plan,China(No.2017YFC1308500)the Public Projects of Zhejiang Province,China(No.2019C03033).
文摘Neural damage has been a great challenge to the medical field for a very long time.The emergence of brain–computer interfaces(BCIs)offered a new possibility to enhance the activity of daily living and provide a new formation of entertainment for those with disabilities.Intracortical BCIs,which require the implantation of microelectrodes,can receive neuronal signals with a high spatial and temporal resolution from the individual’s cortex.When BCI decoded cortical signals and mapped them to external devices,it displayed the ability not only to replace part of the human motor function but also to help individuals restore certain neurological functions.In this review,we focus on human intracortical BCI research using microelectrode arrays and summarize the main directions and the latest results in this field.In general,we found that intracortical BCI research based on motor neuroprosthetics and functional electrical stimulation have already achieved some simple functional replacement and treatment of motor function.Pioneering work in the posterior parietal cortex has given us a glimpse of the potential that intracortical BCIs have to control external devices and receive various sensory information.
