Do large brains of long-living mammals prefer non-newly generated,immature neurons？

Brain plasticity is heterogeneous in mammals：Brain regeneration and repair are the dream of every neurobiologist as well as every common citizen in the world who knows that most neurological diseases,dementia and other age-related problems affecting the central nervous system（CNS）do represent a heavy health and social burden.Efficacious re-generative processes are not＂ a natural property of the mammalian CNS, rather, due to evolutionary constraints they seem substantially reduced （if compared to those occurring in non-mammalian vertebrates） and hardly inducible by therapeutic approaches （reviewed in Martino et al., 2011）.

Brainstem abscesses caused by Listeria monocytogenes:A case report

BACKGROUNDIntracranial Listeria infections are common in newborns and immunocompromisedindividuals, but brainstem abscesses are rare.CASE SUMMARYWe report a rare case of brainstem abscesses caused by Listeria monocytogenes in apreviously healthy adult patient. The patient’s magnetic resonance imagingexamination showed multiple brain abscesses, and his second cerebrospinal fluidculture test indicated the presence of Listeria monocytogenes. Despite earlyempirical therapy, the patient’s condition progressively deteriorated. Because thepatient's abscesses were located in the brainstem and multiple lobes, surgery wasnot possible. The patient died 40 d after admission.CONCLUSIONThis case highlights the importance of rational clinical use of drugs to avoidpotentially serious infectious complications.

Weak cation exchange 2 protein chip for detecting differentially expressed brainstem proteins in a rat model of closed traumatic brain injury

BACKGROUND： Studies have reported the combined use of two-dimensional gel electrophoresis and mass spectrometry to detect differentially expressed proteins in the rat brainstem following brain injury. However, the detected differential proteins often exhibit low sensitivity and high relative molecular weight. Although protein chip technology is thought to compensate for these inadequacies, no related studies or results have been reported. OBJECTIVE： To propose the application of weak cation exchange protein chips in combination with mass spectrometry for determining protein expression profiles and characteristics in the brainstem following closed brain injury. DESIGN, TIME AND SETTING： Randomized, controlled, animal experiments utilizing proteomics were performed from June 2007 to December 2008 in the Proteomics Laboratory, Medical College of Chinese People＇s Armed Police Force. MATERIALS： Weak cation exchange 2 protein chip, Ciphergen Proteinchip System （PBS-IIC）. METHODS： A total of 72 rats were randomly assigned to two groups： sham-surgery （n = 12） and injury （n = 60）. A closed traumatic brain injury model caused by falling object was replicated in the injury group, which was then subdivided into five subgroups according to different time points after injury： 4, 8, 12, 24, and 48 hours, with 12 rats in each subgroup. In the sham-surgery group, only the skin was removed and the stainless steel pad was fixed to the skull. MAIN OUTCOME MEASURES： The brain injury rats were sacrificed at 4, 8, 12, 24, and 48 hours after injury, respectively, and the control rats were sacrificed at 24 hours. Pathological changes in the brainstem were determined using hematoxylin-eosin staining, and differential protein expression in the brainstem was detected using a weak cation exchange 2 protein chip and protein chip reader. RESULTS： In the sham-surgery group, cells appeared normal. However, in the brain injury group, some brainstem neurons exhibited pyknosis, with reduced numbers of Nissl bodies in the cytoplasm swollen cell bodies and nuclei, irregular staining in the cytoplasm, and decreased numbers of neurons. Results from weak cation exchange 2 protein chip detection demonstrated that, compared with the sham-surgery group, the expression profiles of 2 proteins were altered in the brainstem of the injury group. At 12, 24, and 48 hours after injury, expression was increased （P 〈 0.01 ）. The mass charge ratio （M/Z） of 7 862 differentially expressed proteins was greater in the sham-surgery group compared with 12 and 24 hours after injury （P 〈 0.05）. CONCLUSION： The combined method of weak cation exchange 2 protein chip and mass spectrometry detected differential protein expression in the brainstem following closed brain injury in the rats, which suggested that closed brain injury induced altered protein expression profiles in the brainstem.

Quantitative Study on the Asymmetries of the Cortical Speech Zones in Chinese Brains

100 chinese brains were measured to examine the morphological asymmetry of the cortical speech areas with a videoplan computer.The temporal planum was significantly larger on the left than that on the right side(P<0.01).The ratio of R/L was 52.3%.The shapes of the frontal operculum were divided into 6 types.

Protective effect of ultrashortwave versus radix salviae miltiorrhizae on brains of rats with cerebral ischemia-reperfusion injury

BACKGROUND： HOW to control the effect of oxygen-derived free radicals on development of cerebral injury and cerebral edema is a key factor for treating cerebral ischemia-reperfusion injury. OBJECTIVE： To observe and compare the protective effects, synergistic action and mechanisms of ultrashortwave （USW） and radix salviae miltiorrhizae （RSM） on the focal cerebral ischemia-reperfusion injuries in rats. DESIGN： Randomized controlled animal study SEI-FING： Department of Rehabilitation Medicine, First Hospital affiliated to China Medical University MATERIALS： A total of 160 healthy Wistar rats of both genders and aged 18-20 weeks weighing 250-300 g of clean grade were selected in this study. 5 mL/ampoule RSM injection fluid was produced by the First Pharmaceutical Corporation of Shanghai （batch number： 011019, 0.01 mug）. The USW therapeutic device was produced by Shanghai Electronic Device Factory with the frequency of 40.68 MHz and the maximal export power of 40 W. The first channel of power after modulation was 11 W. METHODS： The experiment was carried out in the Rehabilitation Medicine Department of the First Hospital affiliated to China Medical University from May 2002 to January 2003. Focal ischemia-reperfusion model was established in rats by reversible right middle cerebral artery occlusion with filament. Right cerebral ischemia was for 2 hours and then with 24 hours reperfusion. The scores of neurological deficits were evaluated by 0 to 4 scales. After surgery, 64 successful rats models were divided into four groups according to digital table： control group, USW group, RSM group and RSM ＋ USW group with 16 cases in each group. Rats in control group were intraperitoneally injected with the same volume of saline （0.1 mL/g）; rats in USW group were given small dosage of USW on head for 10 minutes at 6 hours after reperfusion; rats in RSM group were intraperitoneally injected with 0.01 mL/g RSM solution at 30 minutes before reperfusion; rats in RSM ＋ USW group were intraperitoneally injected with 0.01 mL/g RSM parenteral solution at 30 minutes before reperfusion and given small dosage of USW on head for 10 minutes once at 6 hours after reperfusion; sixteen rats in sham operation group did not receive any treatment. All 80 rats were taken brains at 24 hours after reperfusion to measure wet and dry weights to calculate water content： Cerebral water content （%） = （1-dry/wet weight） × 100%. Superoxide dismutase （SOD） activity was measured by hydroxylamine method and malondialdehyde （MDA） content was measured by TBA photometric method. MAIN OUTCOME MEASURES ： Cerebral water content, SOD activity and MDA content RESULTS： All 160 rats except 80 failing in modeling were involved in the final analysis. （① The cerebral water content of left hemisphere made no significant difference （P 〉 0.05）. The cerebral water content of right hemisphere in the control group and the three treatment groups was obviously higher than that of the sham operation group [（81.26±0.77）%, （79.74±0.68）%, （79.76±0.81）%, （79.61±0.79）%, （77.43±0.61）%, P 〈 0.05]. The cerebral water content of right hemisphere in the three treatment groups was obviously lower than that of the control group （P〈 0.05）. There was no significant difference among the three treatment groups （P 〉 0.05）. ② Compared with the control group, SOD activity （right） of the control group decreased obviously （P 〈 0.05）, while MDA content increased obviously （P 〈 0.05）. SOD activity in the three therapeutic groups increased obviously, while MDA content decreased obviously （P 〈 0.05）; there was no significant difference among the three treatment groups （P 〉 0.05）. CONCLUSION： ① USW and RSM therapy have neuroprotective effects against focal cerebral ischemia-reperfusion injuries by means of decreasing cerebral water content and MDA and increasing the activity of SOD. ② Synergistic action was not observed between these two therapeutic methods.

Appearance of a neural bypass between injured cingulum and brainstem cholinergic nuclei of a patient with traumatic brain injury on follow-up diffusion tensor tractography images

The human brain is known to contain a maximum of eight cholinergic nuclei： the basal forebrain region： the medial septal nucleus （Ch 1）, the vertical nucleus of the diagonal band （Ch 2）, the horizontal limb of the diago- nal band （Ch 3）, and the nucleus basalis of Meynert （Ch 4）; the brainstem： the pedunculopontine nucleus （Ch 5）, the laterodorsal tegmental nucleus （Ch 6）, and the para- bigeminal nucleus （Ch 8）; and the thalamus： the medial habenular nucleus （Ch 7） （Nieuwenhuys et al., 2008; Naidich and Duvernoy, 2009）. The cingulum is the neu- ral tract extending from the orbitofrontal cortex to the medial temporal lobe （Mufson and Pandya, 1984）. The cingulum plays an important role in memory because it is a passage of the medial cholinergic pathway, which pro- vides cholinergic innervations to the cerebral cortex after originating from Ch 1 and Ch 2 as well as Ch 4 （mainly） （Selden et al., 1998; Nieuwenhuys et al., 2008; Hong and lang, 2010）.

Developing the Potential of Children's Brains

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Analysis of somatic mutations in 131 human brains reveals aging-associated hypermutability

We analyzed 131 human brains (44 neurotypical, 19 with Tourette syndrome, 9 with schizophrenia, and 59 with autism) for somatic mutations after whole genome sequencing to a depth of more than 200×. Typically, brains had 20 to 60 detectable single-nucleotide mutations, but ~6% of brains harbored hundreds of somatic mutations. Hypermutability was associated with age and damaging mutations in genes implicated in cancers and, in some brains, reflected in vivo clonal expansions. Somatic duplications, likely arising during development, were found in ~5% of normal and diseased brains, reflecting background mutagenesis.

Tongguan Liqiao acupuncture therapy improves dysphagia after brainstem stroke

Tongguan Liqiao acupuncture therapy has been shown to effectively treat dysphagia after stroke-based pseudobulbar paralysis. We presumed that this therapy would be effective for dysphagia after bulbar paralysis in patients with brainstem infarction. Sixty-four patients with dysphagia following brainstem infarction were recruited and divided into a medulla oblongata infarction group（n = 22）, a midbrain and pons infarction group（n = 16）, and a multiple cerebral infarction group（n = 26） according to their magnetic resonance imaging results. All patients received Tongguan Liqiao acupuncture for 28 days. The main acupoints were Neiguan（PC6）, Renzhong（DU26）, Sanyinjiao（SP6）, Fengchi（GB20）, Wangu（GB12）, and Yifeng（SJ17）. Furthermore, the posterior pharyngeal wall was pricked. Before and after treatment, patient swallowing functions were evaluated with the Kubota Water Test, Fujishima Ichiro Rating Scale, and the Standard Swallowing Assessment. The Barthel Index was also used to evaluate their quality of life. Results showed that after 28 days of treatment, scores on the Kubota Water Test and Standard Swallowing Assessment had decreased, but scores on the Fujishima Ichiro Rating Scale and Barthel Index had increased in each group. The total efficacy rate was 92.2% after treatment, and was most obvious in patients with medulla oblongata infarction（95.9%）. These findings suggest that Tongguan Liqiao acupuncture therapy can repair the connection of upper motor neurons to the medulla oblongata motor nucleus, promote the recovery of brainstem infarction, and improve patient＇s swallowing ability and quality of life.

Functional electrical stimulation-facilitated proliferation and regeneration of neural precursor cells in the brains of rats with cerebral infarction

Previous studies have shown that proliferation of endogenous neural precursor cells cannot alone compensate for the damage to neurons and axons. From the perspective of neural plastici- ty, we observed the effects of functional electrical stimulation treatment on endogenous neural precursor cell proliferation and expression of basic fibroblast growth factor and epidermal growth factor in the rat brain on the infarct side. Functional electrical stimulation was performed in rat models of acute middle cerebral artery occlusion. Simultaneously, we set up a placebo stimulation group and a sham-operated group. Immunohistochemical staining showed that, at 7 and 14 days, compared with the placebo group, the numbers of nestin （a neural precursor cell marker）-positive cells in the subgranular zone and subventricular zone were increased in the functional electrical stimulation treatment group. Western blot assays and reverse-transcription PCR showed that total protein levels and gene expression of epidermal growth factor and basic fibroblast growth factor were also upregulated on the infarct side. Prehensile traction test results showed that, at 14 days, prehension function of rats in the functional electrical stimulation group was significantly better than in the placebo group. These results suggest that functional electrical stimulation can promote endogenous neural precursor cell proliferation in the brains of acute cerebral infarction rats, enhance expression of basic fibroblast growth factor and epidermal growth factor, and improve the motor function of rats.

Structural and functional alterations in the brains of patients with anisometropic and strabismic amblyopia:a systematic review of magnetic resonance imaging studies

Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention.Previous clinical and neuroimaging studies have suggested that the neural mechanisms underlying strabismic amblyopia and anisometropic amblyopia may be different.Therefore,we performed a systematic review of magnetic resonance imaging studies investigating brain alterations in patients with these two subtypes of amblyopia;this study is registered with PROSPERO(registration ID:CRD42022349191).We searched three online databases(PubMed,EMBASE,and Web of Science) from inception to April 1,2022;39 studies with 633 patients(324patients with anisometropic amblyo pia and 309 patients with strabismic amblyopia) and 580 healthy controls met the inclusion criteria(e.g.,case-control designed,pee r-reviewed articles) and were included in this review.These studies highlighted that both strabismic amblyopia and anisometropic amblyopia patients showed reduced activation and distorted topological cortical activated maps in the striate and extrastriate co rtices during tas k-based functional magnetic resonance imaging with spatial-frequency stimulus and retinotopic representations,respectively;these may have arisen from abnormal visual experiences.Compensations for amblyopia that are reflected in enhanced spontaneous brain function have been reported in the early visual cortices in the resting state,as well as reduced functional connectivity in the dorsal pathway and structural connections in the ventral pathway in both anisometro pic amblyopia and strabismic amblyopia patients.The shared dysfunction of anisometro pic amblyopia and strabismic amblyopia patients,relative to controls,is also chara cterized by reduced spontaneous brain activity in the oculomotor co rtex,mainly involving the frontal and parietal eye fields and the cerebellu m;this may underlie the neural mechanisms of fixation instability and anomalous saccades in amblyopia.With regards to specific alterations of the two forms of amblyo pia,anisometropic amblyo pia patients suffer more microstructural impairments in the precortical pathway than strabismic amblyopia patients,as reflected by diffusion tensor imaging,and more significant dysfunction and structural loss in the ventral pathway.Strabismic amblyopia patients experience more attenuation of activation in the extrastriate co rtex than in the striate cortex when compared to anisometropic amblyopia patients.Finally,brain structural magnetic resonance imaging alterations tend to be lateralized in the adult anisometropic amblyopia patients,and the patterns of brain alterations are more limited in amblyopic adults than in childre n.In conclusion,magnetic resonance imaging studies provide important insights into the brain alterations underlying the pathophysiology of amblyopia and demonstrate common and specific alte rations in anisometropic amblyo pia and strabismic amblyopia patients;these alterations may improve our understanding of the neural mechanisms underlying amblyopia.

Excitatory amino acid changes in the brains of rhesus monkeys following selective cerebral deep hypothermia and blood flow occlusion

Selective cerebral deep hypothermia and blood flow occlusion can enhance brain tolerance to ischemia and hypoxia and reduce cardiopulmonary complications in monkeys. Excitotoxicity induced by the release of a large amount of excitatory amino acids after cerebral ischemia is the major mechanism underlying ischemic brain injury and nerve cell death. In the present study, we used selective cerebral deep hypothermia and blood flow occlusion to block the bilateral common carotid arteries and/or bilateral vertebral arteries in rhesus monkey, followed by reperfusion using Ringer＇s solution at 4~C. Microdialysis and transmission electron microscope results showed that selective cerebral deep hypothermia and blood flow occlusion inhibited the release of glutamic acid into the extracellular fluid in the brain frontal lobe and relieved pathological injury in terms of the ultrastructure of brain tissues after severe cerebral ischemia. These findings indicate that cerebral deep hypothermia and blood flow occlusion can inhibit cytotoxic effects and attenuate ischemic/ hypoxic brain injury through decreasing the release of excitatory amino acids, such as glutamic acid.

The evolution of complex brains and behaviors in African cichlid fishes

In this review, I explore the effects of both social organization and the physical environment, specifically habitat complexity, on the brains and behavior of highly visual African cichlid fishes, drawing on examples from primates and birds where appropriate. In closely related fishes from the monophyletic Ectodinii clade of Lake Tanganyika, both forces influence cichlid brains and behavior. Considering social influences first, visual acuity differs with respect to social organization （monogamy versus polygyny）. Both the telencephalon and amygdalar homologue, area Dm, are larger in monogamous species. Monogamous species are found to have more vasotocin-immunoreactive cells in the preoptic area of the brain. Habitat complexity also influences brain and behavior in these fishes. Total brain size, telencephalic and cerebellar size are positively correlated with habitat complexity. Visual acuity and spatial memory are enhanced in cichlids living in more complex environments. However habitat complexity and social forces affect cichlid brains differently. Taken together, our field data and plasticity data suggest that some of the species-specific neural effects of habitat complexity could be the consequence of the corresponding social correlates. Environmental forces, however, exert a broader effect on brain structures than social ones do, suggesting allometric expansion of the brain structures in concert with brain size and/or co-evolntion of these structures [Current Zoology 56 （1）： 144-156, 2010].

Cloud-Assisted Distributed Edge Brains for Multi-Cell Joint Beamforming Optimization for 6G

In 5G networks,optimization of antenna beam weights of base stations has become the key application of AI for network optimization.For 6G,higher frequency bands and much denser cells are expected,and the importance of automatic and accurate beamforming assisted by AI will become more prominent.In existing network,servers are“patched”to network equipment to act as a centralized brain for model training and inference leading to high transmission overhead,large inference latency and potential risks of data security.Decentralized architectures have been proposed to achieve flexible parameter configuration and fast local response,but it is inefficient in collecting and sharing global information among base stations.In this paper,we propose a novel solution based on a collaborative cloud edge architecture for multi-cell joint beamforming optimization.We analyze the performance and costs of the proposed solution with two other architectural solutions by simulation.Compared with the centralized solution,our solution improves prediction accuracy by 24.66%,and reduces storage cost by 83.82%.Compared with the decentralized solution,our solution improves prediction accuracy by 68.26%,and improves coverage performance by 0.4 dB.At last,the future research work is prospected.

The effects of a 20-week exercise program on blood-circulating biomarkers related to brain health in overweight or obese children:The ActiveBrains project

Background:Emerging research supports the idea that exercise positively affects neurodevelopment.However,the mechanisms linking exercise with brain health are largely unknown.We aimed to investigate the effect of exercise on(a)blood biomarkers selected based on previous evidence(brainderived neurotrophic factor,β-hydroxybutyrate(BHB),cathepsin B(CTSB),kynurenine,fibroblast growth factor 21(FGF21),soluble vascular cell adhesion molecule-1(sVCAM-1));and(b)a panel of 92 neurology-related proteins(discovery analysis).We also investigated whether changes in these biomarkers mediate the effects of exercise on brain health(hippocampal structure and function,cognitive performance,and mental health).Methods:We randomized 81 overweight/obese children(10.1±1.1 years,41%girls)into 2 groups:either 20 weeks of aerobic plus resistance exercise or control.Candidate biomarkers were assessed using enzyme-linked immunosorbent assay(ELISA)for kynurenine,FGF21,and CTSB;colorimetry forβ-hydroxybutyrate;and XMap for brain-derived neurotrophic factor and soluble vascular cell adhesion molecule-1.The92 neurology-related proteins were analyzed by an antibody-based proteomic analysis.Results:Our intervention had no significant effect on candidate biomarkers(all p>0.05).In the discovery analysis,a reduction in circulating macrophage scavenger receptor type-I was observed(standardized differences between groups=-0.3,p=0.001).This effect was validated using ELISA methods(standardized difference=-0.3,p=0.01).None of the biomarkers mediated the effects of exercise on brain health.Conclusions:Our study does not support a chronic effect of exercise on candidate biomarkers.We observed that while chronic exercise reduced the levels of macrophage scavenger receptor type-Ⅰ,it did not mediate the effects of exercise on brain health.Future studies should explore the implications of this novel biomarker for overall health.

TRANSCRANIAL NEAR-INFRARED SPECTROSCOPY OF SMOKING BRAINS

We used a mobile wireless near-infrared sensor for the noninvasive recording of cerebral hemoglobin concentration changes during cigarette smoking.Each measurement included 5 min of rest,5 min of smoking imitation,and 5 min of actual smoking.We observed significant effects of the tobacco smoking on temporal changes in the human brain at time scales ranging from 200 ms to about 1 min.The most reproducible effects were an increase of the heartbeat rate and a decrease in the heartbeat power spectral density during smoking.Significant but highly individual changes due to smoking were observed in temporal patterns of hemodynamic fluctuations in 5–50 s time scales.We have also found statistically significant slow increases in both oxy-and deoxy-hemoglobin concentrations during smoking.

Differential Spontaneous Photon Emissions from Cerebral Hemispheres of Fixed Human Brains: Asymmetric Coupling to Geomagnetic Activity and Potentials for Examining Post-Mortem Intrinsic Photon Information

The emissions of biophotons have been considered a ubiquitous property of living systems and their components. We measured the “spontaneous” photon emissions from fixed whole and sectioned human brains within hyper-dark settings. Significant differences in photon counts were measured from different spatial planes. The flux densities were in the order of 2 × 10-12 W per m2. The right hemispheres but not the left hemispheres displayed more photon emissions whose spectral power density profiles exhibited a conspicuous amplitude peak between 7.9 and 8 Hz. Brains measured in the hyperdark (~10-12 W·m2) after removal from the typical lighting of the laboratory emitted more photons than those that had been maintained in the hyperdark for one week. The significant correlation between the numbers of photons emitted from the left hemisphere (but not the right) and global geomagnetic activity also exhibited energy equivalence between the photon flux densities and the geomagnetic shift within the cerebral volumes. These results indicate that what has been assumed to be fixed unresponsive human brain tissue still emits small numbers of photons that may be residuals from ambient light and can potentially interact with global geomagnetic activity. The medical implications for post-mortem intrinsic photonic information based upon the anisotropic microstructures within the hemispheres of the human cerebrum are discussed.

Morphological and histological changes in the brains of turbot(Scophthalmus maximus)with gonadal development

The brain plays a critical role in controlling reproduction through the hypothalamus-pituitary-gonadal(HPG)axis in vertebrates.Turbot(Scophthalmus maximus)has become an economically important marine fish in Europe and North China.Previous research investigating turbot reproduction has focused on the role of the HPG axis in regulating egg and sperm production.However,the morphology and histology of the organs in the HPG axis have not been studied.In this study,we investigated the morphology and histology of brains in female and male turbot at different stages of gonadal development.The results showed that the brains of both female and male turbot were composed of seven parts that are typical of advanced teleosts:the telencephalon,diencephalon,cerebellum,hypothalamus,pituitary gland,myelencephalon,and olfactory bulbs.The telencephalon was well-developed and contained five distinct lobes,with the contiguous diencephalon at the caudal portion.The torus longitudinales and rostral torus semicircularis of the mesencephalon flattened along the dorsal surface,and the rostral corpus cerebellum was located in the dorsal portion.The actual total brain volume in mature males was significantly greater(p<0.05)than that of females with gonadal development.Notably,the pituitary volume in male turbot significantly increased(p<0.05)from immature to mature stage,but this difference did not occur in females.The data together illustrate a distinct sex difference in the turbot brain during gonadal development,providing insight into their HPG axes.

Characteristics of diffusion-tensor imaging for healthy adult rhesus monkey brains

Diffusion-tensor imaging can be used to observe the microstructure of brain tissue. Fractional ani- sotropy reflects the integrity of white matter fibers. Fractional anisotropy of a young adult brain is low in gray matter, high in white matter, and highest in the splenium of the corpus callosum. Thus, we selected the anterior and posterior limbs of the internal capsule, head of the caudate nucleus, semioval center, thalamus, and corpus callosum （splenium and genu） as regions of interest when using diffusion-tensor imaging to observe fractional anisotropy of major white matter fiber tracts and the deep gray matter of healthy rhesus monkeys aged 4-8 years. Results showed no laterality dif- ferences in fractional anisotropy values. Fractional anisotropy values were low in the head of cau- date nucleus and thalamus in gray matter. Fractional anisotropy values were highest in the sple- nium of corpus callosum in the white matter, followed by genu of the corpus callosum and the pos- terior limb of the internal capsule. Fractional anisotropy values were lowest in the semioval center and posterior limb of internal capsule. These results suggest that fractional anisotropy values in major white matter fibers and the deep gray matter of 4-8-year-old rhesus monkeys are similar to those of healthy young people.