针对采用控制器局域网络(CAN:Controller Area Network)总线的自动操舵系统和采用串口通讯的航海导航设备之间通讯的不匹配问题,设计了一种基于Cortex-M3嵌入式平台的通信转换模块,实现了串口与CAN总线数据的双向转换功能。同时对传统CA...针对采用控制器局域网络(CAN:Controller Area Network)总线的自动操舵系统和采用串口通讯的航海导航设备之间通讯的不匹配问题,设计了一种基于Cortex-M3嵌入式平台的通信转换模块,实现了串口与CAN总线数据的双向转换功能。同时对传统CAN收发器CTM1050存在的信号稳定性不足、波特率精准度低等问题,提出并实现了一种硬件电路的替代方案,提高了数据通讯的时效性和稳定性。基于CAN2.0B扩展帧,设计了自动操舵系统内部CAN总线协议。该协议可根据报文信息优先级分配标识帧,保证了总线数据的有序传输。实验结果表明,该通讯模块功能使用正常且通讯效果良好,具有一定通用性,可在多种需要转换的设备系统上推广使用。展开更多
BACKGROUND ： Functional magnetic resonance imaging （fMRI） studies have disclosed the changes of the motor function in the motor cortex of ipsilateral and contralateral hemispheres of tumor, which have special signi...BACKGROUND ： Functional magnetic resonance imaging （fMRI） studies have disclosed the changes of the motor function in the motor cortex of ipsilateral and contralateral hemispheres of tumor, which have special significance for making the surgical planning and most greatly minimizing the postoperative functional damages. OBJECTIVE： To analyze the association between the manifestation characteristics of hand functional area and motor dysfunction using fMRI in patients with space-occupying lesions of tumor in motor cortex. DESIGN ： A case-controlled observation SETTING： Department of Radiology, Second Affiliated Hospital, Shantou University Medical College .PARTICIPANTS： Twenty-three patients （13 males and 10 females） with space-occupying lesions of central sulcus area, aged 21-53 years with a mean age of （47±1） years were selected from the Second Affiliated Hospital of Shantou University Medical College. All the patients were diagnosed by MR scanning as space-occupying lesions of motor area, and pathologically confirmed that the lesions involved central sulcus and central Iobule; Lesions occurred in left and right hemispheres in 13 and 10 cases respectively. The tumor types were astrocytoma （n =8）, metastatic tumours （n =7）, meningiomas （n =5） and oligodendroglioma （n =3）. The muscle strength was normal in 11 cases （grade 5） and obviously decreased in 12 cases （grade 2-3 in 3 cases and grade 4 in 9 cases）; muscle strengths of both upper and lower limbs were decreased in 7 cases, and only that of upper limbs was decreased in 5 cases. Informed consents were obtained from all the subjects. Meanwhile, 9 healthy physical examinees （5 males and 4 females） of 20-56 years old with an average of （34±1） years were taken as controls. All the patients and healthy subjects were right-handed. METHODS： All the enrolled subjects were examined with MR scanning and functional imaging. Twenty cases whose clinical symptoms were mild in the patient group and 9 healthy volunteers adopted simple active finger-tapping movements, and for the 3 cases whose clinical symptoms were severe in the patient group, the simple passive finger-tapping movements were used. The manifestations in the activated brain areas were analyzed in the patients with brain tumor of different muscle strength and the controls. The motor deficit and activation of contralateral primary motor cortex （M1） in simple finger-tapping movements were observed in the patient group. MAIN OUTCOME MEASURES： （1） Brain areas activated by finger-tapping movements in each group： （2） Activated volumes in hemisphere by finger-tapping movements between groups. RESULTS： The contralateral M1 area could not be activated in 1 case in the patient group,, all the other 22 patients and 9 healthy subjects were involved in the analysis of results. （1） In the control group, unilateral finger tapping movement activated the contralateral primary motor cortex （M1）, bilateral SMA and bilateral PMC. The activation volume was the largest in contralateral primary motor cortex （M1）, smaller in the SMA, and the smallest in PMC. The finger tapping movement in healthy subjects could activate contralateral primary motor cortex （M1）, bilateral SMA and bilateral PMC, which had no obvious differences from the manifestations of brain functional area activated by active finger tapping. There was no significant difference in the volume of activated functional areas between right and left hands. In the patient group, the central sulcos around the tumor in the activated M1 area displaced towards dorsal or ventral side, also extended. The distance of displacement in the functional area was determined as compared with the contralateral central sulcus, and the results suggested the M1 displacement, including that there were 10 cases with the M1 displacement larger than 10 mm in the patients with motor deficit, which were obviously more than in those without motor deficit （n =1, P 〈 0.01）, and the activated volume in contralateral M1 area was obvious smaller in the patients with motor deficit than in those without motor deficit （P 〈 0.01）. （2） The M1 activation and changes were observed in contralateral hemisphere in the patient group, and the activated volume was obviously larger than that in the control group （P 〈 0.01）. The activated volumes of M1 and PMC in ipsilateral hemisphere were obviously larger than those in the control group （P 〈 0.05）, but that of SMA had no obvious difference between the two groups （P 〉 0.05）. CONCLUSION： fMRI can be used to observe the activation of the brain motor functional areas of patient with space-occupying lesions in motor area, and evaluate the state of their motor function. The larger the distance of displacement of M1 compressed by tumor, the more obviously the muscle strength decreases in the patients.展开更多
Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice ...Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and hippocampus.Determining how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress psychopathology.In this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of depression.We focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine circuit.We determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic system.Therefore,BDNF might be a biological indicator regulating stress-related processes in various brain regions.展开更多
BACKGROUND： Functional MRI （fMRI） demonstrates the localization of hand representation in the motor cortex, thereby providing feasible noninvasive mapping of functional activities in the human brain. OBJECTIVE： To...BACKGROUND： Functional MRI （fMRI） demonstrates the localization of hand representation in the motor cortex, thereby providing feasible noninvasive mapping of functional activities in the human brain. OBJECTIVE： To observe cortical activation within different cortical motor regions during repetitive hand movements in healthy subjects through the use of fMRI. DESIGN： An observational study, with each subject acting as his own control. SETTING： Department of Radiology, the First Affiliated Hospital of Nanchang University. PARTICIPANTS： Seven healthy volunteers, 4 males and 3 females, aged 19 to 38 years, participated in the study. All subjects were right-handed, with no neurological or psychological disorders. Informed written consent was obtained from all subjects, and the study was approved by the Institutional Review Board of the First Affiliated Hospital of Nanchang University. METHODS： The study was performed at the Department of Radiology between June-August 2005. A 1.5 Tesla Siemens MRI scanner （Symphony, Germany） was used to acquire T1-weighted structural images, which were oriented parallel to the line running through the anterior and the posterior commissures. Subjects were instructed on a task and were allowed to practice briefly prior to the imaging procedure. The motor activation task consisted of the right hand performing a clenching movement. The T1-W images were acquired from six alternating epochs of rest and activation from all seven healthy subjects. Data were collected with echoplanar imaging of brain oxygen level dependent （BOLD） sequence. Each series comprised six cycles of task performance （30 seconds）, alternating with rest （30 seconds） periods, and 3-second time intervals. The differences between active and baseline fMRI imaging were calculated using the student t-test. Differential maps were overlaid on the high resolution TI-W structural image for neuroanatomical correlation of activation areas. MAIN OUTCOME MEASURES： The omega-shaped hand knobs were recognized on T1-W structural images. Active signal changes in the primary （M1） and secondary motor （M2） areas, as well as the relationship between the hand knobs and M1 area activation, were analyzed. Region of interest was selected for signal change quantitative graphic analysis. RESULTS： All 7 enrolled volunteers were included in the final analysis. In the present study, hand knob structures were recognized on T1-weighted images in all subjects and were omega-shaped in the axial plane. Significant functional activations were observed in the contralateral primary motor area of all subjects. Activation signals were distributed mainly in the central sulcus around the hand knob. The contralateral primary sensory （S1） cortex was activated in most cases, and ipsilateral M1 was activated in 3 subjects. Contralateral or bilateral supplementary motor area （SMA） was also activated in 6 cases. Premotor area, or super parietal lobe, was activated in two subjects. Three-dimensional reconstruction demonstrated that the active signal of M1 was primarily located at the middle-lateral surface of the contralateral precentral gyrus in Brodman＇s area 4, and the signal of SMA activation was located in the mesial surface of the premotor area. CONCLUSION： The knob structure of the precentral gyrus is the representative motor area for hand movement. The cerebral cortical motor network was extensively activated during voluntary hand movements in normal subjects. In alert, conscious human subjects, the activated fMRI signal safely and non-invasively localized and lateralized the motor cortical activity associated with simple voluntary repetitive hand movements. Whether higher cognitive functions, such as perception and speech, can be similarly mapped using the fMRI technique and the BOLD method remains to be determined in future well-designed human studies.展开更多
Nitric oxide is an important neuromodulator in the brain and is involved in the development of visual system. But it is not clear how nitric oxide and nitric oxide synthase （NOS） are involved in the developing visua...Nitric oxide is an important neuromodulator in the brain and is involved in the development of visual system. But it is not clear how nitric oxide and nitric oxide synthase （NOS） are involved in the developing visual cortex of rodents. Thus we examined the expression of NOS activity in the postnatal developing visual cortex of the golden hamster by using histochemical technique for NADPH-diaphorase （NADPH-d）. A heavily stained NADPH-d band was observed in the neuropil of the visual cortex. This NADPH-d band initially appeared in the cortical plate from the day of birth （P0） to postnatal day 4 （P4）. From P7 to P21, this band was confined to area 17 and migrated to the deeper layers Ill IV and V VI before it eventually disappeared at P28. Such developmental trends of the band correlated well with the process of formation and establishment of the geniculo-cortical projection patterns. Thus, the areal specific development of the band suggests that NOS is closely related to the cortical differentiation and synaptic formation of the primary visual cortex. On the other hand, monocular eye enucleation on P1 could not alter the appearance of this NADPH-d positive band, indicating a non-activity dependant role of NOS. In addition, differences in the laminar distributions and developmental sequence between the heavily and lightly stained NADPH-d positive neurons during development suggest that they play different roles in the development.展开更多
The effects of electrical stimulation of second somatosensory area(S Ⅱ)andelectroacupuncture(EA)at Huantiao(GB 30)and Yanglinquan(GB 34)points on nociceptive re-sponses of neurons in the nucleus centrum medianum(CM)i...The effects of electrical stimulation of second somatosensory area(S Ⅱ)andelectroacupuncture(EA)at Huantiao(GB 30)and Yanglinquan(GB 34)points on nociceptive re-sponses of neurons in the nucleus centrum medianum(CM)in the thalamus were respectively ob-served after topical application of bicuculline(Bic)at the motor cortex(MCtx),and the results werecompared with those obtained in the saline control group.It was found that following application ofBic either electrical stimulation of SII(n=11)or EA(n=11)yielded obvious inhibition on nocicep-tive responses of CM neurons(P【0.05),which was similar to the inhibitory effects obtained in thesaline control groups(n=11,n=10).After GABA application at MCtx electrical stimulation of SIIfailed to show inhibition on nociceptive responses in 3 CM neurons.It is indicated that GABA in MC-tx is involved in SII originating corticofugal regulation of nucleus CM in acupuncture analgesia.展开更多
Recent morphological studies in schizophrenia suggest atrophic changes in the neuropil of the prefrontal cortex. Most recently, we showed a schizophrenia-associated decrease in MAP2 in schizophrenia, which we believed...Recent morphological studies in schizophrenia suggest atrophic changes in the neuropil of the prefrontal cortex. Most recently, we showed a schizophrenia-associated decrease in MAP2 in schizophrenia, which we believed is not due to neuroleptic exposure. MAP2 is a very important protein in the assembly of micro-tubule in neurons;therefore, it plays a major role in neuronal processes like dendrites, spines and synapses. Additionally, recent studies from our lab showed decreases in dendrites in area 32 and area 9. In this study we examined the dendrites and spines in area 9 and 17 to determine if neuroleptic drugs play a role. Huntington’s patients take neuroleptics similar to schizophrenics;therefore, by comparing the two groups to controls we can determine if neuroleptics play a role in the deficits reported in schizophrenia. Our results showed a significant decrease in both basal dendrites and spines for both layers III and V in area 9 in schizophrenia compared to controls. The Huntington’s brains, on the other hand, showed no significant difference compared to controls. In area 17, there was also no significant difference when comparing the three groups. The data suggest that neuroleptic drugs may not be responsible for the changes observed in schizophrenia.展开更多
AIM: To explore the existence of potential correlations of cortical thickness between different functional brain areas.METHODS: Our material consisted of 38 formalinfixated human cerebral hemispheres from twenty males...AIM: To explore the existence of potential correlations of cortical thickness between different functional brain areas.METHODS: Our material consisted of 38 formalinfixated human cerebral hemispheres from twenty males and three females, cadaver donors for students' education. We selected the following cortical areas at each hemisphere to examine: supramarginal gyrus(S), angular gyrus(A), area of colors recognition(F), area of names recognition(N), area of auditory attention(H), area of place memory(M), cortex of the superior wall of the calcarine sulcus(V1) and cortex of the inferior wall of the calcarine sulcus(V2). We measured the thickness of each cortical area and statistically analyzed our data.RESULTS: We found a significant difference of the mean value of the V1(P < 0.05) between right and left hemispheres, as well as very significant correlations(P < 0.001) between the following cortical areas: N and F, A and F, S and F, A and S, A and N, S and N. We also found significant correlations(P < 0.01) between the following areas: S and M, S and H, N and H, as well asbetween the following areas(P < 0.05): V1 and V2, M and F, M and N, A and H. CONCLUSION: Our results suggest that there could be a potentially stronger impact for objects placed in the left inferior quarter of the visual field. Our study revealed several thickness-based correlations among different functional cortical areas. Most of them seem to have a more or less rational explanation.展开更多
Totally three articles focusing on “the expression of Nogo-A, Nogo receptor and NADPH-diaphorase in the developing rat visual cortex and the effects of levodopa methyl ester on nerve growth factor expression in visua...Totally three articles focusing on “the expression of Nogo-A, Nogo receptor and NADPH-diaphorase in the developing rat visual cortex and the effects of levodopa methyl ester on nerve growth factor expression in visual cortex area 17 in strabismic amblyopia” are published in three issues. We hope that our readers find these papers useful to their research.展开更多
To understand the connectivity of cerebral cor-tex, especially the spatial and temporal pattern of movement, functional magnetic resonance imaging (fMRI) during subjects performing finger key presses was used to extra...To understand the connectivity of cerebral cor-tex, especially the spatial and temporal pattern of movement, functional magnetic resonance imaging (fMRI) during subjects performing finger key presses was used to extract functional networks and then investigated their character-istics. Motor cortex networks were constructed with activation areas obtained with statistical analysis as vertexes and correlation coefficients of fMRI time series as linking strength. The equivalent non-motor cortex networks were constructed with certain distance rules. The graphic and dynamical measures of motor cor-tex networks and non-motor cortex networks were calculated, which shows the motor cortex networks are more compact, having higher sta-tistical independence and integration than the non-motor cortex networks. It indicates the motor cortex networks are more appropriate for information diffusion.展开更多
文摘针对采用控制器局域网络(CAN:Controller Area Network)总线的自动操舵系统和采用串口通讯的航海导航设备之间通讯的不匹配问题,设计了一种基于Cortex-M3嵌入式平台的通信转换模块,实现了串口与CAN总线数据的双向转换功能。同时对传统CAN收发器CTM1050存在的信号稳定性不足、波特率精准度低等问题,提出并实现了一种硬件电路的替代方案,提高了数据通讯的时效性和稳定性。基于CAN2.0B扩展帧,设计了自动操舵系统内部CAN总线协议。该协议可根据报文信息优先级分配标识帧,保证了总线数据的有序传输。实验结果表明,该通讯模块功能使用正常且通讯效果良好,具有一定通用性,可在多种需要转换的设备系统上推广使用。
基金a grant from theMedical Scientific ResearchFoundation of GuangdongProvince, No. A2003526
文摘BACKGROUND ： Functional magnetic resonance imaging （fMRI） studies have disclosed the changes of the motor function in the motor cortex of ipsilateral and contralateral hemispheres of tumor, which have special significance for making the surgical planning and most greatly minimizing the postoperative functional damages. OBJECTIVE： To analyze the association between the manifestation characteristics of hand functional area and motor dysfunction using fMRI in patients with space-occupying lesions of tumor in motor cortex. DESIGN ： A case-controlled observation SETTING： Department of Radiology, Second Affiliated Hospital, Shantou University Medical College .PARTICIPANTS： Twenty-three patients （13 males and 10 females） with space-occupying lesions of central sulcus area, aged 21-53 years with a mean age of （47±1） years were selected from the Second Affiliated Hospital of Shantou University Medical College. All the patients were diagnosed by MR scanning as space-occupying lesions of motor area, and pathologically confirmed that the lesions involved central sulcus and central Iobule; Lesions occurred in left and right hemispheres in 13 and 10 cases respectively. The tumor types were astrocytoma （n =8）, metastatic tumours （n =7）, meningiomas （n =5） and oligodendroglioma （n =3）. The muscle strength was normal in 11 cases （grade 5） and obviously decreased in 12 cases （grade 2-3 in 3 cases and grade 4 in 9 cases）; muscle strengths of both upper and lower limbs were decreased in 7 cases, and only that of upper limbs was decreased in 5 cases. Informed consents were obtained from all the subjects. Meanwhile, 9 healthy physical examinees （5 males and 4 females） of 20-56 years old with an average of （34±1） years were taken as controls. All the patients and healthy subjects were right-handed. METHODS： All the enrolled subjects were examined with MR scanning and functional imaging. Twenty cases whose clinical symptoms were mild in the patient group and 9 healthy volunteers adopted simple active finger-tapping movements, and for the 3 cases whose clinical symptoms were severe in the patient group, the simple passive finger-tapping movements were used. The manifestations in the activated brain areas were analyzed in the patients with brain tumor of different muscle strength and the controls. The motor deficit and activation of contralateral primary motor cortex （M1） in simple finger-tapping movements were observed in the patient group. MAIN OUTCOME MEASURES： （1） Brain areas activated by finger-tapping movements in each group： （2） Activated volumes in hemisphere by finger-tapping movements between groups. RESULTS： The contralateral M1 area could not be activated in 1 case in the patient group,, all the other 22 patients and 9 healthy subjects were involved in the analysis of results. （1） In the control group, unilateral finger tapping movement activated the contralateral primary motor cortex （M1）, bilateral SMA and bilateral PMC. The activation volume was the largest in contralateral primary motor cortex （M1）, smaller in the SMA, and the smallest in PMC. The finger tapping movement in healthy subjects could activate contralateral primary motor cortex （M1）, bilateral SMA and bilateral PMC, which had no obvious differences from the manifestations of brain functional area activated by active finger tapping. There was no significant difference in the volume of activated functional areas between right and left hands. In the patient group, the central sulcos around the tumor in the activated M1 area displaced towards dorsal or ventral side, also extended. The distance of displacement in the functional area was determined as compared with the contralateral central sulcus, and the results suggested the M1 displacement, including that there were 10 cases with the M1 displacement larger than 10 mm in the patients with motor deficit, which were obviously more than in those without motor deficit （n =1, P 〈 0.01）, and the activated volume in contralateral M1 area was obvious smaller in the patients with motor deficit than in those without motor deficit （P 〈 0.01）. （2） The M1 activation and changes were observed in contralateral hemisphere in the patient group, and the activated volume was obviously larger than that in the control group （P 〈 0.01）. The activated volumes of M1 and PMC in ipsilateral hemisphere were obviously larger than those in the control group （P 〈 0.05）, but that of SMA had no obvious difference between the two groups （P 〉 0.05）. CONCLUSION： fMRI can be used to observe the activation of the brain motor functional areas of patient with space-occupying lesions in motor area, and evaluate the state of their motor function. The larger the distance of displacement of M1 compressed by tumor, the more obviously the muscle strength decreases in the patients.
基金supported financially by the National Natural Science Foundation of China,No.82071272(to YZ).
文摘Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and hippocampus.Determining how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress psychopathology.In this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of depression.We focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine circuit.We determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic system.Therefore,BDNF might be a biological indicator regulating stress-related processes in various brain regions.
文摘BACKGROUND： Functional MRI （fMRI） demonstrates the localization of hand representation in the motor cortex, thereby providing feasible noninvasive mapping of functional activities in the human brain. OBJECTIVE： To observe cortical activation within different cortical motor regions during repetitive hand movements in healthy subjects through the use of fMRI. DESIGN： An observational study, with each subject acting as his own control. SETTING： Department of Radiology, the First Affiliated Hospital of Nanchang University. PARTICIPANTS： Seven healthy volunteers, 4 males and 3 females, aged 19 to 38 years, participated in the study. All subjects were right-handed, with no neurological or psychological disorders. Informed written consent was obtained from all subjects, and the study was approved by the Institutional Review Board of the First Affiliated Hospital of Nanchang University. METHODS： The study was performed at the Department of Radiology between June-August 2005. A 1.5 Tesla Siemens MRI scanner （Symphony, Germany） was used to acquire T1-weighted structural images, which were oriented parallel to the line running through the anterior and the posterior commissures. Subjects were instructed on a task and were allowed to practice briefly prior to the imaging procedure. The motor activation task consisted of the right hand performing a clenching movement. The T1-W images were acquired from six alternating epochs of rest and activation from all seven healthy subjects. Data were collected with echoplanar imaging of brain oxygen level dependent （BOLD） sequence. Each series comprised six cycles of task performance （30 seconds）, alternating with rest （30 seconds） periods, and 3-second time intervals. The differences between active and baseline fMRI imaging were calculated using the student t-test. Differential maps were overlaid on the high resolution TI-W structural image for neuroanatomical correlation of activation areas. MAIN OUTCOME MEASURES： The omega-shaped hand knobs were recognized on T1-W structural images. Active signal changes in the primary （M1） and secondary motor （M2） areas, as well as the relationship between the hand knobs and M1 area activation, were analyzed. Region of interest was selected for signal change quantitative graphic analysis. RESULTS： All 7 enrolled volunteers were included in the final analysis. In the present study, hand knob structures were recognized on T1-weighted images in all subjects and were omega-shaped in the axial plane. Significant functional activations were observed in the contralateral primary motor area of all subjects. Activation signals were distributed mainly in the central sulcus around the hand knob. The contralateral primary sensory （S1） cortex was activated in most cases, and ipsilateral M1 was activated in 3 subjects. Contralateral or bilateral supplementary motor area （SMA） was also activated in 6 cases. Premotor area, or super parietal lobe, was activated in two subjects. Three-dimensional reconstruction demonstrated that the active signal of M1 was primarily located at the middle-lateral surface of the contralateral precentral gyrus in Brodman＇s area 4, and the signal of SMA activation was located in the mesial surface of the premotor area. CONCLUSION： The knob structure of the precentral gyrus is the representative motor area for hand movement. The cerebral cortical motor network was extensively activated during voluntary hand movements in normal subjects. In alert, conscious human subjects, the activated fMRI signal safely and non-invasively localized and lateralized the motor cortical activity associated with simple voluntary repetitive hand movements. Whether higher cognitive functions, such as perception and speech, can be similarly mapped using the fMRI technique and the BOLD method remains to be determined in future well-designed human studies.
基金the Fundamental Research Funds for the Central Universities,No.21609101the National Basic Research Program of China (973 Program),No.2011CB707501
文摘Nitric oxide is an important neuromodulator in the brain and is involved in the development of visual system. But it is not clear how nitric oxide and nitric oxide synthase （NOS） are involved in the developing visual cortex of rodents. Thus we examined the expression of NOS activity in the postnatal developing visual cortex of the golden hamster by using histochemical technique for NADPH-diaphorase （NADPH-d）. A heavily stained NADPH-d band was observed in the neuropil of the visual cortex. This NADPH-d band initially appeared in the cortical plate from the day of birth （P0） to postnatal day 4 （P4）. From P7 to P21, this band was confined to area 17 and migrated to the deeper layers Ill IV and V VI before it eventually disappeared at P28. Such developmental trends of the band correlated well with the process of formation and establishment of the geniculo-cortical projection patterns. Thus, the areal specific development of the band suggests that NOS is closely related to the cortical differentiation and synaptic formation of the primary visual cortex. On the other hand, monocular eye enucleation on P1 could not alter the appearance of this NADPH-d positive band, indicating a non-activity dependant role of NOS. In addition, differences in the laminar distributions and developmental sequence between the heavily and lightly stained NADPH-d positive neurons during development suggest that they play different roles in the development.
基金This project is supported by National Natural Science Fundation of China
文摘The effects of electrical stimulation of second somatosensory area(S Ⅱ)andelectroacupuncture(EA)at Huantiao(GB 30)and Yanglinquan(GB 34)points on nociceptive re-sponses of neurons in the nucleus centrum medianum(CM)in the thalamus were respectively ob-served after topical application of bicuculline(Bic)at the motor cortex(MCtx),and the results werecompared with those obtained in the saline control group.It was found that following application ofBic either electrical stimulation of SII(n=11)or EA(n=11)yielded obvious inhibition on nocicep-tive responses of CM neurons(P【0.05),which was similar to the inhibitory effects obtained in thesaline control groups(n=11,n=10).After GABA application at MCtx electrical stimulation of SIIfailed to show inhibition on nociceptive responses in 3 CM neurons.It is indicated that GABA in MC-tx is involved in SII originating corticofugal regulation of nucleus CM in acupuncture analgesia.
文摘Recent morphological studies in schizophrenia suggest atrophic changes in the neuropil of the prefrontal cortex. Most recently, we showed a schizophrenia-associated decrease in MAP2 in schizophrenia, which we believed is not due to neuroleptic exposure. MAP2 is a very important protein in the assembly of micro-tubule in neurons;therefore, it plays a major role in neuronal processes like dendrites, spines and synapses. Additionally, recent studies from our lab showed decreases in dendrites in area 32 and area 9. In this study we examined the dendrites and spines in area 9 and 17 to determine if neuroleptic drugs play a role. Huntington’s patients take neuroleptics similar to schizophrenics;therefore, by comparing the two groups to controls we can determine if neuroleptics play a role in the deficits reported in schizophrenia. Our results showed a significant decrease in both basal dendrites and spines for both layers III and V in area 9 in schizophrenia compared to controls. The Huntington’s brains, on the other hand, showed no significant difference compared to controls. In area 17, there was also no significant difference when comparing the three groups. The data suggest that neuroleptic drugs may not be responsible for the changes observed in schizophrenia.
文摘AIM: To explore the existence of potential correlations of cortical thickness between different functional brain areas.METHODS: Our material consisted of 38 formalinfixated human cerebral hemispheres from twenty males and three females, cadaver donors for students' education. We selected the following cortical areas at each hemisphere to examine: supramarginal gyrus(S), angular gyrus(A), area of colors recognition(F), area of names recognition(N), area of auditory attention(H), area of place memory(M), cortex of the superior wall of the calcarine sulcus(V1) and cortex of the inferior wall of the calcarine sulcus(V2). We measured the thickness of each cortical area and statistically analyzed our data.RESULTS: We found a significant difference of the mean value of the V1(P < 0.05) between right and left hemispheres, as well as very significant correlations(P < 0.001) between the following cortical areas: N and F, A and F, S and F, A and S, A and N, S and N. We also found significant correlations(P < 0.01) between the following areas: S and M, S and H, N and H, as well asbetween the following areas(P < 0.05): V1 and V2, M and F, M and N, A and H. CONCLUSION: Our results suggest that there could be a potentially stronger impact for objects placed in the left inferior quarter of the visual field. Our study revealed several thickness-based correlations among different functional cortical areas. Most of them seem to have a more or less rational explanation.
文摘Totally three articles focusing on “the expression of Nogo-A, Nogo receptor and NADPH-diaphorase in the developing rat visual cortex and the effects of levodopa methyl ester on nerve growth factor expression in visual cortex area 17 in strabismic amblyopia” are published in three issues. We hope that our readers find these papers useful to their research.
文摘To understand the connectivity of cerebral cor-tex, especially the spatial and temporal pattern of movement, functional magnetic resonance imaging (fMRI) during subjects performing finger key presses was used to extract functional networks and then investigated their character-istics. Motor cortex networks were constructed with activation areas obtained with statistical analysis as vertexes and correlation coefficients of fMRI time series as linking strength. The equivalent non-motor cortex networks were constructed with certain distance rules. The graphic and dynamical measures of motor cor-tex networks and non-motor cortex networks were calculated, which shows the motor cortex networks are more compact, having higher sta-tistical independence and integration than the non-motor cortex networks. It indicates the motor cortex networks are more appropriate for information diffusion.
