In this study, we analyzed diffusion tensor imaging （DTI） results of brain white matter in rhesus macaques （Macaca mulatta） with four different parameter settings and found that the sequence A （b=1000 s/mm^2, spatial resolution=1.25 mm ×1.25 mm× 1.25 mm, numbers of direction=33, NSA=3） and B （b=800 s/mm^2, spatial resolution= 1.25 mm× 1.25 mm× 1.25 mm, numbers of direction=33, NSA=3） could accurately track coarse fibers. The fractional anisotropy （FA） derived from sequence C （b=1000s/mm^2, spatial resolution=0.55 mm×0.55 mm×2.5 mm, direction number=33, NSA=3） was too fuzzy to be used in tracking white matter fibers. By comparison, the high resolution and the FA with high contrast of gray matter and white matter derived from sequence D （b=800 s/mm^2, spatial resolution=1.0 mm×1.0 mm ×1.0 mm, numbers of direction=33, NSA=3） qualified in its application in tracking both thick and thin fibers, making it an optimal DTI setting for rhesus macaques.
Impaired cognitive function,along with positive and negative symptoms,is a core clinical feature of schizophrenia.Earlier studies suggest that impaired cognitive functioning should be assessed from the perspective of brain networks.The recently developed brainnetome approach to evaluating brain networks-an approach that was initially developed by Chinese scientists-provides a new methodology for studying this issue.In this paper we first introduce the concept of brainnetome.We then review recent progress in developing a brainnetome of impaired cognitive function in people with schizophrenia.The models of the relevant brain networks considered were created using data obtained from functional and anatomical brain imaging technologies at different levels of analysis:networks centered on regions of interest,networks related to specific cognitive functions,whole brain networks,and the attributes of brain networks.Finally,we discuss the current challenges and potential new directions for research about brainnetome.
In animal societies, some stressful events can lead to higher levels of physiological stress. Such stressors, like social rank, also predict an increased vulnerability to an array of diseases. However, the physiological relationship between social rank and stress varies between different species, as well as within groups of a single species. For example, dominant individuals are more socially stressed at times, while at other times it is the subordinate ones who experience this stress. Together, these variations make it difficult to assess disease vulnerability as connected to social interactions. In order to learn more about how physiological rank relationships vary between groups of a single species, cortisol measurements from hair samples were used to evaluate the effects of dominance rank on long-term stress levels in despotic and less stringent female rhesus macaque hierarchal groups. In despotic groups, cortisol levels were found not to be correlated with social rank, but a negative correlation was found between social rank and cortisol levels in less stringent hierarchies. Low ranking monkeys in less stringent groups secreted elevated levels of cortisol compared to higher ranking animals. These data suggest that variations in the strictness of the dominance hierarchy are determining factors in rank related stress physiology. The further consideration of nonhuman primate social system diversity and the linear degree of their hierarchies may allow for the development of valid rank-related stress models that will help increase our understanding and guide the development of new therapeutics for diseases related to human socioeconomic status.
To proceed from sensation to movement, integration and transformation of information from different senses and reference frames are required. Several brain areas are involved in this transformation process, but previous neuroanatomical and neurophysiological studies have implicated the caudal area 7b as one particular component of this transformation system. In this study, we present the first quantitative report on the spatial coding properties of caudal area 7b. The results showed that neurons in this area had intermediate component characteristics in the transformation system; the area contained bimodal neurons, and neurons in this area encode spatial information using a hybrid reference frame. These results provide evidence that caudal area 7b may belong to the reference frame transformation system, thus contributing to our general understanding of the transformation system.
Hui-Hui JIANGYing-Zhou HUJian-Hong WANGYuan-Ye MAXin-Tian HU
In animal societies,some stressful events can lead to higher levels of physiological stress.Such stressors,like social rank,also predict an increased vulnerability to an array of diseases.However,the physiological relationship between social rank and stress varies between different species,as well as within groups of a single species.For example,dominant individuals are more socially stressed at times,while at other times it is the subordinate ones who experience this stress.Together,these variations make it difficult to assess disease vulnerability as connected to social interactions.In order to learn more about how physiological rank relationships vary between groups of a single species,cortisol measurements from hair samples were used to evaluate the effects of dominance rank on long-term stress levels in despotic and less stringent female rhesus macaque hierarchal groups.In despotic groups,cortisol levels were found not to be correlated with social rank,but a negative correlation was found between social rank and cortisol levels in less stringent hierarchies.Low ranking monkeys in less stringent groups secreted elevated levels of cortisol compared to higher ranking animals.These data suggest that variations in the strictness of the dominance hierarchy are determining factors in rank related stress physiology.The further consideration of nonhuman primate social system diversity and the linear degree of their hierarchies may allow for the development of valid rank-related stress models that will help increase our understanding and guide the development of new therapeutics for diseases related to human socioeconomic status.
To proceed from sensation to movement,integration and transformation of information from different senses and reference frames are required.Several brain areas are involved in this transformation process,but previous neuroanatomical and neurophysiological studies have implicated the caudal area 7b as one particular component of this transformation system.In this study,we present the first quantitative report on the spatial coding properties of caudal area 7b.The results showed that neurons in this area had intermediate component characteristics in the transformation system;the area contained bimodal neurons,and neurons in this area encode spatial information using a hybrid reference frame.These results provide evidence that caudal area 7b may belong to the reference frame transformation system,thus contributing to our general understanding of the transformation system.
Hui-Hui JIANGYing-Zhou HUJian-Hong WANGYuan-Ye MAXin-Tian HU
吗啡是一种有效的镇痛药,但易使动物产生耐受性和成瘾性。在该实验中,中缅树鼩(Tupai a belangeri chinensis)连续7d,每天接受三次肌肉注射递增剂量(5、10、15、20mg/kg体重)吗啡后对吗啡产生耐受和依赖;吗啡注射完成后,腹腔注射纳洛酮(1.25mg/kg体重)催瘾,可诱导其条件性位置厌恶(conditioned place aversion,CPA)及相应吗啡戒断症状的出现。该结果提示树鼩慢性吗啡依赖模型的建立可用于研究吗啡依赖和耐受的生物学机制,以及减轻戒断症状药物的筛选。
The brain is organized as a hierarchy of complex networks on different temporal and spatial scales. The complex con- nectivities within the brain are presented in the anatomical architecture as well as dynamic activity. There have long been efforts to make a connection map of the brain [1], and this has now been achieved with the establishment of the connectome [2]. The connectome framework is of central significance for understanding how the brain works at a detailed level [3], however, the connectome can only pro- vide a structural description of the brain [2]. It is essential to understand the brain through integrating multi-level net- work features obtained using various functional and ana- tomical brain imaging technologies on different scales,
The serotonin-transporter-linked polymorphic region(5-HTTLPR)is associated with mood disorders.This association is thought to be due to amygdala hyperresponsiveness to negative emotional stimuli as a result of reduced frontal cortical control.In Caucasians,the short form is associated with this effect,but in Han Chinese we recently found that the long form is involved.Serotonin receptors have rich expression in default mode network(DMN)regions and the recent studies have found an association between the short form of the 5-HTTLPR and DMN functional connectivity(FC)in Caucasians.The present study has investigated whether there may also be anethnic difference in this influence of 5-HTTLPR on the DMN.We recruited 233 young Han Chinese subjects and calculated the resting-state default-network FC.Our study found that the L carriers had decreased FC in the bilateral medial prefrontal cortex,right parahippocampal gyrus,left middle temporal gyrus,and increased FC in left precuneus(Pcu)compared to SS.The PCC-Pcu FC in L carriers was significantly negatively correlated with the depression scores.Our findings,therefore,suggest that there is also a difference between Caucasian and Han Chinese subjects in the association between the different forms of the5-HTTLPR and DMN functional connectivity.
Haixia LongBing LiuBing HouChao WangKeith M. KendrickChunshui YuTianzi Jiang
