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The macaque model has been widely used to investigate the brain mechanisms of specific cognitive functions and psychiatric disorders. However, a detailed functional architecture map of the macaque cortex in vivo is still lacking. Here, we aimed to construct a new macaque cortex atlas based on its anatomical connectivity profiles using in vivo diffusion MRI. First, we defined the macaque cortical seed areas using the NeuroMaps atlas. Then, we applied the anatomical connectivity patterns-based parcellation approach to parcellate the macaque cortex into 80 subareas in each hemisphere, which were approximately symmetric between the two hemispheres. In each hemisphere, we identified 14 subareas in the frontal cortex, 9 subareas in the somatosensory cortex, 13 subareas in the parietal cortex, 16 subareas in the temporal cortex, 16 subareas in the occipital cortex, and 12 subareas in the limbic system. Finally, the graph-based network analyses of the anatomical network based on newly constructed macaque cortex atlas identified seven hub areas including bilateral ventral premotor cortex, bilateral superior parietal lobule, right medial precentral gyrus, and right precuneus. This newly constructed macaque cortex atlas may facilitate studies of the structure and functions of the macaque brain in the future.

Embryonic stem cells (ESCs) have enormous potential as novel cell-based therapies, but their effectiveness depends on stem cell differentiation and specific signaling regulators, which remain poorly understood. In this study, a kisspeptin peptide (KP-10) was used at different dosages to determine whether rhesus macaque-derived tau GFP-Lyon ES cells underwent kisspeptin-specific neuronal differentiation. It was found that KP-10 exhibited an anti-proliferative effect on the cells and led to morphological changes and cellular differentiation consistent with neuronal stem cell (NSC) development. The cells differentiated into Gonadotrophin Releasing Hormone (GnRH) neuronal-like cell types in response to the KP-10 treatment. There has been a previously observed connection between kisspeptin signaling, GnRH neurons and their dysfunction found in congenital disorders like idiopathic hypogonadotropic hypogonadism (IHH). Although therapeutics are a still a far-off goal, the formation and development of GnRH-positive neuronal-like cells following the application of KP-10 to Lyon NSC cells opens the door for future NSC-based therapies to treat specific reproductive disorders.

To address the problems caused by low ability of quality analysis and decision-making in the process of complex product assembly, in this paper, we proposed a digital twin-based approach for quality control and optimization of complex product assembly, by providing a digital twin system to realize the timely and precisely interactive mapping between the physical world and digital world. Specifically, a quality control and optimization mechanism is presented, which provides the theoretical support to the realization of the digital twin-based approach. A data-driven quality control model is introduced to solve the optimization problem by considering the panoramic assembly quality data. A digital twin system for complex product assembly is elaborated by providing detailed deployment and implementation procedures, which includes (1) building of the digital entity of an assembly line, (2) real-time online sensing in multi-source heterogeneous environment, (3) real-time simulation of equipment and assembly process, (4) realization of the intelligent production scheduling under uncertainty conditions, and (5) dynamical adjustment of the assembly process. Finally, the paper presents the validation results considering the practical applications of the proposed approach in real industrial fields.

Over the past 40 years, research has addressed the impact of the aging process on various aspects of visual function. Most studies have focused on age-related visual impairment in low-level local features of visual objects, such as orientation, contrast sensitivity and spatial frequency. However, whether there are lifespan changes in global visual perception is still unclear. To suitably frame this question, we defined global visual patterns by a topological approach, and local visual patterns were manipulated with different levels of geometrical invariants in descending order of structural stability from projective, affine, and then Euclidean features. Using the Configural Superiority Effect, we investigated the influence of aging on local and global visual perception through a comparison of young and old adults in Experiment 1; moreover, we provided continuous-aging data from 21 to 78 years of age to investigate age-related changes in visual perception in Experiment 2. We found a large perceptual decline across increasing age groups in local geometrical perception: for example, Euclidean (orientation), affine (parallelism), and projective (collinearity) discrimination. Moreover, the study provides a counterintuitive finding that global topological perception resists the aging process and remains constant throughout adult lifespan. These findings highlight the possibility that for humans, global topology may be a stable and fundamental component by which visual systems represent and characterize objects. ispartof: JOURNAL OF VISION vol:19 issue:1 ispartof: location:United States status: published

We present a model of information that integrates two competing perspectives of information by emulating the Chinese philosophy of yin-yang. The model embraces the two key dimensions of information that exist harmoniously: information as (1) objective and veridical representations in the world (information as object) and (2) socially constructed interpretations that are a result of contextual influences (information as subject). We argue that these two facets of information cocreate information as a unified system and complement one another through two processes, which we denote as forming and informing. While the information literature has historically treated these objective and subjective identities of information as incompatible, we argue that they are mutually relevant and that our understanding of one actually enhances our understanding of the other.

Chronic stress is an important cause for depression. However, not everyone who is exposed to chronic stress will develop depression. Our previous studies demonstrated that early adversity can cause lasting changes in adolescent rhesus monkeys, but depressive symptoms have not been observed. Compared to adults, it is still unknown that whether adolescent rhesus monkeys experiencing early adversity are more likely to develop depressive symptoms. In this study, we investigated the long term relationship between early adversity, chronic stress and adolescent depression for the first time. Eight male rhesus monkeys were reared in maternal separation (MS) or mother-reared (MR) conditions. All of them went through unpredictable chronic stress for two months at their age four. The stressors included space restriction, intimidation, long illumination and fasting. Behavioral and physiological data were collected during the experiment. The results showed that, compared with the MR group, the locomotor activity of MS group was significantly decreased after one month of chronic stress while huddling up and stereotypical behaviors were significantly increased. Moreover, this trend continued and even worsened at the second month. Significantly higher hair cortisol levels and lower body weight were observed in MS group after two months of stress. These results indicate that early adversity is one of the environmental factors which can increase the susceptibility of depression when experiencing chronic stress in the later life. This will further clarify the important roles of early environmental factors in the development of adolescent depression and children rearing conditions should receive more attention.

Drug addicts experience strong craving episodes in response to drug-associated cues. Attenuating these responses using pharmacological or behavioral approaches could aid recovery from addiction. Cue-induced drug seeking can be modeled using the conditioned place preference procedure (CPP). Our previous work showed that conditioned place preference (CPP) can be induced by administration of increasing doses of morphine in rhesus monkeys. Here, we investigated whether expression of morphine-induced CPP can be attenuated by inhibiting activity of insular cortex or by repeated unreinforced exposures to the CPP test. The insula has been demonstrated to be involved in addiction to several drugs of abuse. To test its role in morphine CPP, bilateral cannulae were implanted into the insula in seven adult monkeys. The CPP was established using a biased apparatus by intramuscular injections of morphine at increasing doses (1.5, 3.0 and 4.5mg/kg) for each monkey. After the monkeys established morphine CPP, their insulae were reversibly inactivated by bilateral microinjection with 5% lidocaine (40μl) prior to the post-conditioning test (expression) of CPP using a within-subject design. The microinjections of lidocaine failed to affect CPP expression when compared to saline injections. We subsequently investigated morphine-associated memory during six episodes of CPP tests performed in these monkeys over the following 75.0±0.2months. While the preference score showed a declining trend with repeated testing, morphine-induced CPP was maintained even on the last test performed at 75months post-conditioning. This observation indicated strong resistance of morphine-induced memories to extinction in rhesus monkeys. Although these data do not confirm involvement of insula in morphine-induced CPP, our observation that drug-associated memories can be maintained over six drug-free years following initial experience with morphine has important implications for treatment of drug addiction using extinction therapy.

Phencyclidine (PCP) could induce schizophrenia (Sz) like behavior in both humans and animals, therefore, has been widely utilized to establish Sz animal models. It induced cognitive deficits, the core symptom of Sz, mainly through influencing frontal dopaminergic function. Nonhuman primate (NHP) studies demonstrated impaired object retrieval detour (ORD) and spatial delayed response (SDR) task performance by acute or chronic PCP treatment. However, NHP investigations, continually monitoring SDR performance before, during and after PCP treatment, are lacking. Present study investigated the long-term influence of chronic PCP treatment on SDR performance and the possible increase of SDR deficit severity and duration by the incremental dosing procedure in rhesus monkeys. SDR task was performed repeatedly up to eight weeks after constant dosing procedure (i.m., 0.3 mg/kg, day 12-25), during which drug effects on locomotor activity and blood cortisol concentration were assessed. Incremental dosing procedure (starting dose 0.3 mg/kg, day 6-19) began five months later. Constant dosing procedure induced differential level of hyperactivity across testing days, without significant influence on blood cortisol concentration. It reduced SDR performance, until occurrence of the first and worst impairment on day 15 and 23 respectively. The impaired performance recovered to pretreatment level over one week after drug cessation. In contrast, incremental dosing procedure impaired SDR performance on the first treatment day, which recovered within treatment period. Results suggested increase of SDR deficit severity by repeated PCP administrations, whereas the incremental dosing procedure did not increase SDR deficit severity and duration.

This work is intended to increase the classification accuracy of single EEG epoch, reduce the number of repeated stimuli, and improve the information transfer rate (ITR) of P300 Speller. Target EEG epochs and nontarget EEG ones are both mapped to a space by Wavelet. In this space, Fisher Criterion is used to measure the difference between target and nontarget ones. Only a few Daubechies wavelet bases corresponding to big differences are selected to construct a matrix, by which EEG epochs are transformed to feature vectors. To ensure the online experiments, the computation tasks are distributed to several computers that are managed and integrated by Storm so that they could be parallelly carried out. The proposed feature extraction was compared with the typical methods by testing its performance of classifying single EEG epoch and detecting characters. Our method achieved higher accuracies of classification and detection. The ITRs also reflected the superiority of our method. The parallel computing scheme of our method was deployed on a small scale Storm cluster containing three desktop computers. The average feedback time for one round of EEG epochs was 1.57 ms. The proposed method can improve the performance of P300 Speller BCI. Its parallel computing scheme is able to support fast feedback required by online experiments. The number of repeated stimuli can be significantly reduced by our method. The parallel computing scheme not only supports our wavelet feature extraction but also provides a framework for other algorithms developed for P300 Speller.

Introduction “Where to begin” is a fundamental question of vision. A “Global‐first” topological approach proposed that the first step in object representation was to extract topological properties, especially whether the object had a hole or not. Numerous psychophysical studies found that the hole (closure) could be rapidly recognized by visual system as a primitive property. However, neuroimaging studies showed that the temporal lobe (IT), which lied at a late stage of ventral pathway, was involved as a dedicated region. It appeared paradoxical that IT served as a key region for processing the early component of visual information. Did there exist a distinct fast route to transit hole information to IT? We hypothesized that a fast noncortical pathway might participate in processing holes. Methods To address this issue, a backward masking paradigm combined with functional magnetic resonance imaging (fMRI) was applied to measure neural responses to hole and no‐hole stimuli in anatomically defined cortical and subcortical regions of interest (ROIs) under different visual awareness levels by modulating masking delays. Results For no‐hole stimuli, the neural activation of cortical sites was greatly attenuated when the no‐hole perception was impaired by strong masking, whereas an enhanced neural response to hole stimuli in non‐cortical sites was obtained when the stimulus was rendered more invisible. Conclusions The results suggested that whereas the cortical route was required to drive a perceptual response for no‐hole stimuli, a subcortical route might be involved in coding the hole feature, resulting in a rapid hole perception in primitive vision.

Glial-restricted precursor (GRP) cells, the earliest glial progenitors for both astrocytes and oligodendrocytes, have been derived from embryos and embryonic stem cells (ESC) in rodents. However, knowledge regarding the equivalent cell type in primates is limited due to restrictions imposed by ethics and resources. Here we report successful derivation and characterization of primate GRP cells from rhesus monkey ESC. The purified monkey GRP cells were A2B5-positive and FGF2-dependent for survival and proliferation. The differentiation assays indicated that they were tri-potential in vitro and bi-potential in vivo. These newly purified GRP cells will help to facilitate understanding of the molecular mechanism of glial development in primates as well as provide a source of therapeutic donor cells for use in neuroregenerative medicine.

The prefrontal cortex is implicated in cognitive functioning and schizophrenia. Prefrontal dysfunction is closely associated with the symptoms of schizophrenia. In addition to the features typical of schizophrenia, patients also present with aspects of cognitive disorders. Based on these relationships, a monkey model mimicking the cognitive symptoms of schizophrenia has been made using treatment with the non-specific competitive N-methyl-D-aspartate receptor antagonist, phencyclidine. The symptoms are ameliorated by atypical antipsychotic drugs such as clozapine. The beneficial effects of clozapine on behavioral impairment might be a specific indicator of schizophrenia-related cognitive impairment.

Early brain development is a complex and rapid process, the disturbance of which may cause the onset of brain disorders. Based on longitudinal imaging data acquired from 6 to 16 months postnatal, we describe a systematic trajectory of monkey brain development during late infancy, and demonstrate the influence of phencyclidine (PCP) on this trajectory. Although the general developmental trajectory of the monkey brain was close to that of the human brain, the development in monkeys was faster and regionally specific. Gray matter volume began to decrease during late infancy in monkeys, much earlier than in humans in whom it occurs in adolescence. Additionally, the decrease of gray matter volume in higher-order association regions (the frontal, parietal and temporal lobes) occurred later than in regions for primary functions (the occipital lobe and cerebellum). White matter volume displayed an increasing trend in most brain regions, but not in the occipital lobe, which had a stable volume. In addition, based on diffusion tensor imaging, we found an increase in fractional anisotropy and a decrease in diffusivity, which may be associated with myelination and axonal changes in white matter tracts. Meanwhile, we tested the influence of 14-day PCP treatment on the developmental trajectories. Such treatment tended to accelerated brain maturation during late infancy, although not statistically significant. These findings provide comparative information for the understanding of primate brain maturation and neurodevelopmental disorders.

Brain imaging studies have identified two cortical areas, the parahippocampal place area (PPA) and the retrosplenial complex (RSC), that respond preferentially to the viewing of scenes. Contrary to the PPA, little is known about the functional maturation and cognitive control of the RSC. Here we used functional magnetic resonance imaging and tasks that required attention to scene (or face) images and suppression of face (or scene) images, respectively, to investigate task-dependent modulation of activity in the RSC and whole-brain functional connectivity (FC) of this area in 7-11-year-old children and young adults. We compared responsiveness of the RSC with that of the PPA. The RSC was selectively activated by scene images in both groups, albeit less than the PPA. Children modulated activity between the tasks similarly in the RSC and PPA, and to the same extent as adults in PPA, whereas adults modulated activity in the RSC less than in PPA. In children, the whole brain FC of the RSC was stronger in the Sf than Fs task between the left RSC and right fusiform gyrus. The between groups comparison suggested stronger FC in children than adults in the Sf task between the right RSC and the left inferior parietal lobule and intraparietal sulcus. Together the results suggest that the function of the RSC and the related networks undergo dynamic changes over the development from 7-11-year-old children to adulthood.

There is a close neuroanatomical connection between odor and emotional processing. Olfactory dysfunction is found in various neurodegenerative and neuropsychiatric disorders. Here, mice take the cyclic nucleotide gated channel 2 mutant gene (Cnga2), which is critical for olfactory sensory neurons to generate odor induced action potentials were used. The Cnga2 mice were congenitally anosmic. Adult mice were tested in a series behavioral paradigm such as open field, light/dark box, forced swim test and Y-maze. Our study found that Cnga2 mice showed increased anxiety- and depressive-like behaviors than their wide type siblings. However, Cnga2 mice showed no difference from the wide types when tested in the two-trial recognition Y-maze. The results indicate that innate olfactory deficiency might modulate emotional behaviors in mice.

Background Transcranial direct current stimulation (tDCS) is an effective approach to modulate brain region functions. We assessed if a single tDCS session over the bilateral frontal-parietal-temporal (FPT) areas would reduce cue induced craving in heroin addicts. Methods Twenty non-treated, long-term heroin-addicted subjects were randomly assigned to receive either real tDCS (1.5 mA, cathodal over bilateral FPT for 20 min) or control tDCS stimulation (turning off the stimulation after 30 s). The participants received heroin cue exposure (containing both injection and inhalation procedures) before and after stimulation and rated their craving after each block of cue presentation. Results Stimulation of the bilateral FPT with real tDCS for 20 min reduced craving scores significantly (68 ± 8.4 pre-stimulation vs. 43 ± 7.6 post-stimulation, p = 0.003), while the control stimulation group showed no significant changes. No side effects of tDCS were reported. Conclusions One session of tDCS over bilateral FPT area significantly reduced subjective craving score induced by heroin cues in heroin addicted subjects.

The dorsolateral prefrontal cortex (DLPFC) is considered to play a crucial role in many high-level functions, such as cognitive control and emotional regulation. Many studies have reported that the DLPFC can be activated during the processing of emotional information in tasks requiring working memory. However, it is still not clear whether modulating the activity of the DLPFC influences emotional perception in a detection task. In the present study, using transcranial direct-current stimulation (tDCS), we investigated (1) whether modulating the right DLPFC influences emotional face processing in a detection task, and (2) whether the DLPFC plays equal roles in processing positive and negative emotional faces. The results showed that anodal tDCS over the right DLPFC specifically facilitated the perception of positive faces, but did not influence the processing of negative faces. In addition, anodal tDCS over the right primary visual cortex enhanced performance in the detection task regardless of emotional valence. Our findings suggest, for the first time, that modulating the right DLPFC influences emotional face perception, especially faces showing positive emotion.

In humans, cues associated with the rewarding effect of drugs of abuse induce drug craving and activate drug-associated memories after prolonged abstinence. In animal studies with the self-administration (SA) paradigm, responses to drug-associated cues increase within time after extinction, a phenomenon described as incubation of craving. Conditioned place preference (CPP) is widely used to measure the rewarding effect of drugs and the reward memory thereof. However, little is known whether responses to drug associated cues progressively increase after abstinence from the drugs in the CPP paradigm. To test whether the drug-associated cues could increase specific responses over the abstinence period in the CPP paradigm, we employed the high dose morphine-induced CPP paradigms in rats and tree shrews in the present study. We examined the CPP scores and the entrances to side chambers of the CPP apparatus to check whether they would progressively increase in the CPP paradigms. Twenty-one male adult Sprague-Dawley rats and eight adult male tree shrews were used to establish morphine-induced CPP and another ten rats treated with saline were controls for the rat experiments. After morphine conditioning, rats and tree shrews showed significant higher CPP scores at the first or second post tests than at baseline but then the CPP scores in the abstinence period decreased gradually. During the abstinence period, animals with morphine-conditioning experiences entered progressively more times to both side compartments, whereas the number of entrances to side chambers of the saline group in rats had no such significant differences. These findings suggest that progressively increased entrances to the side chambers in the extended abstinence period reflect the incubation of craving in high dose morphine-induced CPP paradigms. Also, our data imply that reward memory and drug craving can be distinguished in the CPP paradigm.

Prepulse inhibition (PPI) refers to a decreased response to a startling stimulus when another weaker stimulus precedes it. Most PPI studies have focused on the physiological startle reflex and fewer have reported the PPI of cortical responses. We recorded local field potentials (LFPs) in four monkeys and investigated whether the PPI of auditory cortical responses (alpha, beta, and gamma oscillations and evoked potentials) can be demonstrated in the caudolateral belt of the superior temporal gyrus (STGcb). We also investigated whether the presence of a conspecific, which draws attention away from the auditory stimuli, affects the PPI of auditory cortical responses. The PPI paradigm consisted of Pulse-only and Prepulse + Pulse trials that were presented randomly while the monkey was alone (ALONE) and while another monkey was present in the same room (ACCOMP). The LFPs to the Pulse were significantly suppressed by the Prepulse thus, demonstrating PPI of cortical responses in the STGcb. The PPI-related inhibition of the N1 amplitude of the evoked responses and cortical oscillations to the Pulse were not affected by the presence of a conspecific. In contrast, gamma oscillations and the amplitude of the N1 response to Pulse-only were suppressed in the ACCOMP condition compared to the ALONE condition. These findings demonstrate PPI in the monkey STGcb and suggest that the PPI of auditory cortical responses in the monkey STGcb is a pre-attentive inhibitory process that is independent of attentional modulation.

Gene-editing technologies have made it feasible to create nonhuman primate models for human genetic disorders. Here, we report detailed genotypes and phenotypes of TALEN-edited MECP2 mutant cynomolgus monkeys serving as a model for a neurodevelopmental disorder, Rett syndrome (RTT), which is caused by loss-of-function mutations in the human MECP2 gene. Male mutant monkeys were embryonic lethal, reiterating that RTT is a disease of females. Through a battery of behavioral analyses, including primate-unique eye-tracking tests, in combination with brain imaging via MRI, we found a series of physiological, behavioral, and structural abnormalities resembling clinical manifestations of RTT. Moreover, blood transcriptome profiling revealed that mutant monkeys resembled RTT patients in immune gene dysregulation. Taken together, the stark similarity in phenotype and/or endophenotype between monkeys and patients suggested that gene-edited RTT founder monkeys would be of value for disease mechanistic studies as well as development of potential therapeutic interventions for RTT.

Honeybee is a widely used insect model for learning and memory research. Recently, it has become a potentially good subject for evaluating the effects of addictive drugs on the nervous systems. Our previous study has found that acute morphine injection affected associative memory and locomotor activity in honeybees. In the current study, the effect of chronic morphine treatment and its cessation in honeybees were assessed. The results demonstrated that 1) chronic morphine (0.01, 0.1 and 1 mg/ml) treatment for 7 days severely diminished associative memory in honeybees; 2) 1 mg/ml morphine consumption for 5, 7 and 10 but not 3 days impaired the olfactory memory; 3) Bees withdrawn from morphine for 1 day but not 3 days showed amnesia in the PER conditioning. We also found that bees displayed hyperactivity and tolerance in response to chronic morphine administration. In addition, morphine dose-dependently altered the sucrose responsiveness of bees. The data indicated that chronic morphine has sensory-motor effects and may impair learning and/or memory in honeybees, which were comparative to that in vertebrates.

A recently established link between formaldehyde, a methanol metabolite, and Alzheimer's disease (AD) pathology has provided a new impetus to investigate the chronic effects of methanol exposure. This paper expands this investigation to the non-human primate, rhesus macaque, through the chronic feeding of young male monkeys with 3% methanol ad libitum. Variable Spatial Delay Response Tasks of the monkeys found that the methanol feeding led to persistent memory decline in the monkeys that lasted 6 months beyond the feeding regimen. This change coincided with increases in tau protein phosphorylation at residues T181 and S396 in cerebrospinal fluid during feeding as well as with increases in tau phosphorylated aggregates and amyloid plaques in four brain regions postmortem: the frontal lobe, parietal lobe, temporal lobe, and the hippocampus. Tau phosphorylation in cerebrospinal fluid was found to be dependent on methanol feeding status, but phosphorylation changes in the brain were found to be persistent 6 months after the methanol feeding stopped. This suggested the methanol feeding caused long-lasting and persistent pathological changes that were related to AD development in the monkey. Most notably, the presence of amyloid plaque formations in the monkeys highlighted a marked difference in animal systems used in AD investigations, suggesting that the innate defenses in mice against methanol toxicity may have limited previous investigations into AD pathology. Nonetheless, these findings support a growing body of evidence that links methanol and its metabolite formaldehyde to AD pathology.

Many brain regions are involved in smoking addiction (e.g. insula, ventral tegmental area, prefrontal cortex and hippocampus), and the manipulation of the activity of these brain regions can show a modification of smoking behavior. Low current transcranial direct current stimulation (tDCS) is a noninvasive way to manipulate cortical excitability, and thus brain function and associated behaviors. In this study, we examined the effects of inhibiting the frontal-parietal-temporal association area (FPT) on attention bias to smoking-related cues and smoking behavior in tobacco users. This inhibition is induced by cathodal tDCS stimulation. We tested three stimulation conditions: 1) bilateral cathodal over both sides of FPT; 2) cathodal over right FPT; and 3) sham-tDCS. Visual attention bias to smoking-related cues was evaluated using an eye tracking system. The measurement for smoking behavior was the number of daily cigarettes consumed before and after tDCS treatment. We found that, after bilateral cathodal stimulation of the FPT area, while the attention to smoking-related cues showed a decreased trend, the effects were not significantly different from sham stimulation. The daily cigarette consumption was reduced to a significant level. These effects were not seen under single cathodal tDCS or sham-tDCS. Our results show that low current tDCS of FPT area attenuates smoking cue-related attention and smoking behavior. This non-invasive brain stimulation technique, targeted at FPT areas, might be a promising method for treating smoking behavior.

Cognitive functions are often studied using event-related potentials (ERPs) that are usually estimated by an averaging algorithm. Clearly, estimation of single-trial ERPs can provide researchers with many more details of cognitive activity than the averaging algorithm. A novel method to estimate single-trial ERPs is proposed in this paper. This method includes two key ideas. First, singular value decomposition was used to construct a matrix, which mapped single-trial electroencephalographic recordings (EEG) into a low-dimensional vector that contained little information from the spontaneous EEG. Second, we used the theory of compressed sensing to build a procedure to restore single-trial ERPs from this low-dimensional vector. ERPs are sparse or approximately sparse in the frequency domain. This fact allowed us to use the theory of compressed sensing. We verified this method in simulated and real data. Our method and dVCA (differentially variable component analysis), another method of single-trial ERPs estimation, were both used to estimate single-trial ERPs from the same simulated data. Results demonstrated that our method significantly outperforms dVCA under various conditions of signal-to-noise ratio. Moreover, the single-trial ERPs estimated from the real data by our method are statistically consistent with the theories of cognitive science.

Recently, resting-state functional magnetic resonance imaging has been used to parcellate the brain into functionally distinct regions based on the information available in functional connectivity maps. However, brain voxels are not independent units and adjacent voxels are always highly correlated, so functional connectivity maps contain redundant information, which not only impairs the computational efficiency during clustering, but also reduces the accuracy of clustering results. The aim of this study was to propose feature-reduction approaches to reduce the redundancy and to develop semi-simulated data with defined ground truth to evaluate these approaches. We proposed a feature-reduction approach based on the Affinity Propagation Algorithm (APA) and compared it with the classic featurereduction approach based on Principal Component Analysis (PCA). We tested the two approaches to the parcellation of both semi-simulated and real seed regions using the K-means algorithm and designed two experiments to evaluate their noiseresistance. We found that all functional connectivity maps (with/without feature reduction) provided correct information for the parcellation of the semisimulated seed region and the computational efficiency was greatly improved by both featurereduction approaches. Meanwhile, the APA-based feature-reduction approach outperformed the PCAbased approach in noise-resistance. The results suggested that functional connectivity maps can provide correct information for cortical parcellation, and feature-reduction does not significantly change the information. Considering the improvement in computational efficiency and the noise-resistance, feature-reduction of functional connectivity maps before cortical parcellation is both feasible and necessary.

Developmental studies have demonstrated that cognitive processes such as attention, suppression of interference and memory develop throughout childhood and adolescence. However, little is currently known about the development of top-down control mechanisms and their influence on cognitive performance. In the present study, we used functional magnetic resonance imaging to investigate modulation of activity in the ventral visual cortex in healthy 7–11-year-old children and young adults. The participants performed tasks that required attention to either face (Fs task) or scene (Sf task) images while trying to ignore distracting scene or face images, respectively. A face-selective area in the fusiform gyrus (fusiform face area, FFA) and an area responding preferentially to scene images in the parahippocampal gyrus (parahippocampal place area, PPA) were defined using functional localizers. Children responded slower and less accurately in the tasks than adults. In children, the right FFA was less selective to face images and regulation of activity between the Fs and Sf tasks was weaker compared to adults. In the PPA, selectivity to scenes and regulation of activity, there according to the task demands were comparable between children and adults. During the tasks, children activated prefrontal cortical areas including the middle (MFG) and superior (SFG) frontal gyrus more than adults. Functional connectivity between the right FFA and left MFG was stronger in adults than children in the Fs task. Children, on the other hand, had stronger functional connectivity than adults in the Sf task between the right FFA and right PPA and between right MFG and medial SFG. There were no group differences in the functional connectivity between the PPA and the prefrontal cortex (PFC). Together the results suggest that, in 7–11-year-old children, the FFA is still immature, whereas the selectivity to scenes and regulation of activity in the PPA is comparable to adults. The results also indicated functional immaturity of the PFC in children compared to adults and weaker connectivity between the PFC and the rFFA, explaining the weaker regulation of activity in the rFFA between the Fs and Sf tasks.

Adolescence is a critical developmental stage during which substantial remodeling occurs in brain areas involved in emotional and learning processes. Although a robust literature on the biological effects of extremely low frequency magnetic fields (ELF-MFs) has been documented, data on the effects of ELF-MF exposure during this period on cognitive functions remain scarce. In this study, early adolescent male mice were exposed from postnatal day (P) 23-35 to a 50 Hz MF at 2 mT for 60 min/day. On P36-45, the potential effects of the MF exposure on spatial memory performance were examined using the Y-maze and Morris water maze tasks. The results showed that the MF exposure did not affect Y-maze performance but improved spatial learning acquisition and memory retention in the water maze task under the present experimental conditions.

The clinical use of morphine to reduce pain is limited because of its drug tolerance, dependence and addiction. In the present study, the tree shrews (Tupaia belangeri chinensis) developed morphine tolerance and chronic morphine dependence by morphine injections with increasing doses (5, 10, 15, 20 mg/kg body weight for 7 days). Meanwhile, the naloxone (1.25 mg/kg body weight)-induced conditioned place aversion (CPA) and the withdrawal symptom were also found. The tree shrew model of chronic morphine dependence can be used to investigate the withdrawal symptoms and to select potential withdrawal symptoms reducing drugs in the future.

© 2016 The Author(s). The temporal organization of activity/rest or sleep/wake rhythms for mammals is regulated by the interaction of light/dark cycle and circadian clocks. The neural and molecular mechanisms that confine the active phase to either day or night period for the diurnal and the nocturnal mammals are unclear. Here we report that prokineticin 2, previously shown as a circadian clock output molecule, is expressed in the intrinsically photosensitive retinal ganglion cells, and the expression of prokineticin 2 in the intrinsically photosensitive retinal ganglion cells is oscillatory in a clock-dependent manner. We further show that the prokineticin 2 signaling is required for the activity and arousal suppression by light in the mouse. Between the nocturnal mouse and the diurnal monkey, a signaling receptor for prokineticin 2 is differentially expressed in the retinorecipient suprachiasmatic nucleus and the superior colliculus, brain projection targets of the intrinsically photosensitive retinal ganglion cells. Blockade with a selective antagonist reveals the respectively inhibitory and stimulatory effect of prokineticin 2 signaling on the arousal levels for the nocturnal mouse and the diurnal monkey. Thus, the mammalian diurnality or nocturnality is likely determined by the differential signaling of prokineticin 2 from the intrinsically photosensitive retinal ganglion cells onto their retinorecipient brain targets.

This paper develops a new distributed power control scheme for a power splitting-based interference channel (IFC) with simultaneous wireless information and power transfer (SWIPT). The considered IFC consists of multiple source-destination pairs. Each destination splits its received signal into two parts for information decoding and energy harvesting (EH), respectively. Each pair adjusts its transmit power and power splitting ratio to meet both the signal-to-interference-plus-noise ratio (SINR) and EH constraints at its corresponding destination. To characterize rational behaviors of source-destination pairs, we formulate a non-cooperative game for the considered system, where each pair is modeled as a strategic player who aims to minimize its own transmit power under both SINR and EH constraints at the destination. We derive a sufficient and necessary condition for the existence and uniqueness of the Nash equilibrium (NE) of the formulated game. The best response strategy of each player is derived and then the NE can be achieved iteratively. Numerical results show that the proposed game-theoretic approach can achieve a near-optimal performance under various SINR and EH constraints., Accepted to appear in IEEE Transactions on Vehicular Technology

The prefrontal cortex (PFC) is responsible for executive functions, including planning, goal setting, problem solving, inhibitory control, monitoring, and action adjusting. Executive functions also include selective attention and the flexibility or switching of attention; therefore, attention is an executive function in which the PFC participates. Working memory (WM), which is the temporary maintenance and processing of particular information, is usually considered to be a basic neural mechanism underlying the executive functions. This review systematically discusses the relationship between the prefrontal WM and attention and emphasizes two forms of prefrontal attention. The first form occurs in the dlPFC, which encodes the location of objects with respect to the position of the head, thereby providing a frame of reference from which the focus of attention can be centered. The second occurs in the inferior convexity of the prefrontal cortex (IFC), which encodes the different attributes (shape, texture, color) of objects to enable the ability to focus on one or to switch attention between sensory attributes of objects.

Animals attain information about their environment through different sense organs. For example, the dominant external resource about the environment for rodents is obtained through olfaction. Many environmental conditions (stress or enriched environment) are known to affect an animal's susceptibility to drug addiction. However, it is not known how external information is integrated and paired with drug stimuli to develop into addictive behavior. Here, we investigated the effects of olfactory epithelium lesions induced with ZnSO4 effusion (ZnE) on morphine-induced sensitization and conditioned place preference in mice. We found that the lesion of the olfactory epithelium attenuated the repeated morphine (40 mg/kg)-induced behavioral sensitization and morphine-induced conditioned place preference (CPP) behaviors, such as hyper-locomotion during morphine (40 mg/kg) conditioned training. Additionally, the expression of FosB-like proteins, transcription factors associated with behavioral alterations, in the nucleus accumbens of the brain was attenuated in morphine administered mice treated by ZnE. Taken together, these results indicated that lesion of the olfactory epithelium lead to a decrease in morphine sensitization and CPP behavior in mice as well as modulate specific molecular markers of neuroadaption to drugs of abuse. These findings also suggest that olfaction plays an important role in the development of addictive behaviors that can be modulated by external actions. (C) 2012 Elsevier B.V. All rights reserved.

The dorsal-lateral prefrontal cortex (dlPFC) has been proposed to be the site of spatial working memory (WM), and this concept has had a profound influence on functional studies of the prefrontal cortex (PFC). The concept of spatial WM has been understood to mean that the location of an object is memorized for a short period of time. However, this concept of space is a simplification. To process the spatial information, different spatial frames can be used. In this review, the authors present data from their own laboratory to argue that the dlPFC is related to the egocentric spatial information processing (ESIP) in WM. The goal of this review is to introduce and discuss the egocentric spatial reference frame (ESRF) located in the dlPFC. The ESIP in the PFC might be involved in self-recognition.

Degradation of visual function is a common phenomenon during aging and likely mediated by change in the impaired central visual pathway. Treatment with GABA or its agonist could recover the ability of visual neurons in the primary visual cortex of senescent macaques. However, little is known about how GABAergic system change is related to the aged degradation of visual function in nonhuman primate. With the use of quantitative PCR method, we measured the expression change of 24 GABA related genes in the primary visual cortex (Brodmann's 17) of different age groups. In this study, both of mRNA and protein of glutamic acid decarboxylase (GAD65) were measured by real-time RT-PCR and Western blot, respectively. Results revealed that the level of GAD65 message was not significantly altered, but the proteins were significantly decreased in the aged monkey. As GAD65 plays an important role in GABA synthesis, the down-regulation of GAD65 protein was likely the key factor leading to the observed GABA reduction in the primary visual cortex of the aged macaques. In addition, 7 of 14 GABA receptor genes were up-regulated and one GABA receptor gene was significantly reduced during aging process even after Banjamini correction for multiple comparisons (P0.05). These results suggested that the dysregulation of GAD65 protein might contribute to some age-related neural visual dysfunctions and most of GABA receptor genes induce a clear indication of compensatory effect for the reduced GABA release in the healthy aged monkey cortex.

Maternal separation (MS), which can lead to hypothalamic pituitary adrenal axis dysfunction and behavioral abnormalities in rhesus monkeys, is frequently used to model early adversity. Whether this deleterious effect on monkeys is reversible by later experience is unknown. In this study, we assessed the basal hair cortisol in rhesus monkeys after 1.5 and 3 y of normal social life following an early separation. These results showed that peer-reared monkeys had significantly lower basal hair cortisol levels than the mother-reared monkeys at both years examined. The plasma cortisol was assessed in the monkeys after 1.5 y of normal social life, and the results indicated that the peak in the peer-reared cortisol response to acute stressors was substantially delayed. In addition, after 3 y of normal social life, abnormal behavioral patterns were identified in the peer-reared monkeys. They showed decreases in locomotion and initiated sitting together, as well as increases in stereotypical behaviors compared with the mother-reared monkeys. These results demonstrate that the deleterious effects of MS on rhesus monkeys cannot be compensated by a later normal social life, suggesting that the effects of MS are long-lasting and that the maternal-separated rhesus monkeys are a good animal model to study early adversity and to investigate the development of psychiatric disorders induced by exposure to early adversity.

The surround suppression of the receptive field is important for basic visual information processing, such as orientation specificity. To date, the effects of aging on the strength of surround suppression are not clear. To address this issue, we carried out extracellular single-unit studies of the receptive field properties of cells in the primary visual cortex (area V1) in young and old rhesus (Macaca mulatta) monkeys. When presented with the oriented central stimulus, we found that cells in old animals showed reduced orientation and direction selectivity compared with those in young animals. When presented with the oriented central stimulus together with the optimal surround stimulus, more selective cells {orientation bias (OB) ≥ 0.1; a bias of 0.1 is significant at the P < 0.005 level} in animals of both ages showed reduced orientation selectivity compared with the experiment that presented only the oriented central stimulus. When presented with the optimal central stimulus together with the oriented surround stimulus, cells in old animals showed reduced orientation and direction selectivity compared with young animals. Moreover, broadly tuned cells (OB

Previous studies have confirmed that both honeybee and Drosophila are capable of learning and memory. This study aimed to investigate whether the house fly ( Aldrichina grahami ), with strong instincts to adapt their living environment, have the learning ability to associate odor stimulus to avoid electric shock in free flying state using a device developed by the authors. The result showed the learning ability of A. grahami at the electric shock voltages of 5 V, 25 V and 45 V AC. When 60 V was used, the flies were frequently injured. Our results indicate that A. grahami is a good model to study the neural mechanism of learning and memory. The paradigm in this study has some advantages that can be used in future studies of free insects.

We examined the role of the orbitofrontal cortex (OFC) on exploration of the novel environment using the open-field and Y-maze behavioral paradigms to assess the novelty-seeking behavior of the male Sprague-Dawley rats after receiving bilateral electrolytic lesions of the OFC or sham lesions. In the open-field task, the rats with OFC lesions exhibited reduced average ambulation distance and average rearing number when compared with the animals with sham lesions. Moreover, rats with OFC lesions showed less duration of visits and number of entries in the novel arm in the Y-maze task than the control animals. The current findings suggest that the OFC plays an important role on the novelty-seeking behavior in rats.

Saccades may play an important role in mental disorders research and diagnosis. Not only can saccade be used to help researchers to acquire the early and specific neuropathological changes, but also be a criterion of new drug development and drug efficacy tests. Abnormalities of saccadic eye movement appear in Parkinson's disease, Alzheimer's disease and major depressive disorder patients, but difficulties for its applications arise from unclear processes of neuropathological development and individual differences in patients. Establishing nonhuman primates' model of mental disorders and monitoring saccadic parameters during the model construction will help us to overcome such difficulties.

Bats (Chiroptera) are the second-most abundant mammalian order in the world, occupying a diverse range of habitats and exhibiting many different life history traits. In order to contribute to this highly underrepresented group we describe the sleep architecture of two species of frugivorous bat, the greater short-nosed fruit bat (Cynopterus sphinx) and the lesser dawn fruit bat (Eonycteris spelaea). Electroencephalogram (EEG) and electromyogram (EMG) data were recorded from multiple individuals (>or=5) by telemetry over a 72-h period in a laboratory setting with light/dark cycles equivalent to those found in the wild. Our results show that over a 24-h period both species spent more time asleep than awake (mean 15 h), less than previous reported for Chiroptera (20 h). C. sphinx spent significantly more of its non-rapid eye movement sleep (NREM) and rapid eye movement sleep (REM) quotas during the light phase, while E. spelaea divided its sleep-wake architecture equally between both light and dark phases. Comparing the sleep patterns of the two species found that C. sphinx had significantly fewer NREM and REM episodes than E. spelaea but each episode lasted for a significantly longer period of time. Potential hypotheses to explain the differences in the sleep architecture of C. sphinx with E. spelaea, including risk of predation and social interaction are discussed.

Navigated transcranial magnetic stimulation (TMS) combined with diffusion-weighted magnetic resonance imaging (DW-MRI) and tractography allows investigating functional anatomy of the human brain with high precision. Here we demonstrate that working memory (WM) processing of tactile temporal information is facilitated by delivering a single TMS pulse to the middle frontal gyrus (MFG) during memory maintenance. Facilitation was obtained only with a TMS pulse applied to a location of the MFG with anatomical connectivity to the primary somatosensory cortex (S1). TMS improved tactile WM also when distractive tactile stimuli interfered with memory maintenance. Moreover, TMS to the same MFG site attenuated somatosensory evoked responses (SEPs). The results suggest that the TMS-induced memory improvement is explained by increased top-down suppression of interfering sensory processing in S1 via the MFG-S1 link. These results demonstrate an anatomical and functional network that is involved in maintenance of tactile temporal WM.

Acute drug use modifies brain function in critical ways, and prolonged drug use causes pervasive changes in brain function that persist long after withdrawal. Our previous studies proved that acute or four-day morphine injection impaired mice spatial recognition memory in the Y-maze, but the impairment was short and reversible. In the present study, morphine or saline (40 mg/ kg·day, ip) was injected into mice for 21 days. Spatial recognition memory was tested in the Y-maze on the 2nd, 9th and 19th withdrawal day. Our results showed that spatial recognition memory of morphine-injected mice was impaired on each of the three test days. Our study clearly suggests that long-term morphine use leads to more persistent impairments of spatial recognition memory.

Learning and memory play an important role in morphine addiction. Status epilepticus (SE) can impair the spatial and emotional learning and memory. However, little is known about the effects of SE on morphine-induced conditioned place preference (CPP). The present study was designed to investigate the effects of SE on morphine CPP, with food CPP being used as a control. The effects of SE on spatial memory in the Morris water maze (MWM) and Y-maze were investigated. SE was induced in adult mice using intraperitoneal injection of pentylenetetrazole; control mice received saline. The data indicated that SE had no effects on the formation of morphine CPP; however, the formation of food CPP was blocked by SE. Meanwhile, spatial memory assayed in the MWM and Y-maze was impaired by SE. In addition, the data demonstrated that SE did not cause a lasting disturbance of motor activity nor a change in the mice's appetite. These results suggested that although SE had no effects on morphine CPP, there was impaired food CPP and spatial memory in both the MWM and the Y-maze. The mechanisms underlying memory process of morphine CPP may be different from other types of memory.

The prefrontal cortex (PFC) has a central role in working memory (WM). Resistance to distraction is considered a fundamental feature of WM and PFC neuronal activity. However, although unexpected stimuli often disrupt our work, little is known about the underlying neuronal mechanisms involved. In the present study, we investigated whether irregularly presented distracters disrupt WM task performance and underlying neuronal activity. We recorded single neuron activity in the PFC of 2 monkeys performing WM tasks and investigated effects of auditory and visual distracters on WM performance and neuronal activity. Distracters impaired memory task performance and affected PFC neuronal activity. Distraction that was of the same sensory modality as the memorandum was more likely to impair WM performance and interfere with memory-related neuronal activity than information that was of a different sensory modality. The study also shows that neurons not involved in memory processing in less demanding conditions may become engaged in WM processing in more demanding conditions. The study demonstrates that WM performance and underlying neuronal activity are vulnerable to irregular distracters and suggests that the PFC has mechanisms that help to compensate for disruptive effects of external distracters.

Background and objectives Pentobarbital and ketamine are commonly used in animal experiments, including studies on the effects of ageing on the central nervous system. The electroencephalogram is a sensitive measure of brain activity. The present study investigated, under anaesthesia induced by the two drugs, whether cortical electroencephalogram in aged rats differs from that in young rats. Methods Electroencephalogram was recorded for young (2–3 months) and aged (15–17 months) rats before and during pentobarbital (40 mg kg −1 ) or ketamine (100 mg kg −1 ) anaesthesia. The relative power in five frequency bands (delta: 2–4 Hz; theta: 4–8 Hz; alpha: 8–12 Hz; beta: 12–20 Hz; gamma: 20–100 Hz) was analysed, and then compared between the two age groups. Results In both age groups, pentobarbital anaesthesia induced an increase in relative power in alpha and beta bands and a decrease in the theta band, but the degree of these power variations was more marked in aged rats. Ketamine anaesthesia increased relative power in the delta band and decreased that in the theta band; these effects were significantly different between the two age groups, with aged rats showing more markedly decreased power in the theta band. Conclusions (a) Pentobarbital and ketamine modified cortical electrical activity in a different manner as a function of age; (b) the modification of electroencephalogram relative power with anaesthesia was identical in young and aged rats but quantitatively more marked in aged rats. These findings will be useful in designing experiments that assess pathological changes in the central nervous system during ageing.

Human visual function declines with age. Much of this decline is mediated by changes in the central visual pathways. In this study we compared the spatial and temporal sensitivities of striate cortical cells in young and old paralysed macaque monkeys. Extracellular single-unit recordings were employed. Our results show that cortical neurons in old monkeys exhibit lower optimal spatial and temporal frequencies, lower spatial resolution and lower high temporal frequency cut-offs than do cells in young adult monkeys. These changes in old monkeys are accompanied by increased visually evoked responses, increased spontaneous activities and decreased signal-to-noise ratios. The increased excitability of cells in old animals is consistent with an age-related degeneration of intracortical inhibition. The degradation of spatial and temporal function in old striate cortex should contribute to the decline in visual function that accompanies normal aging.

1. In the present study, we investigated the short- and long-term effects of extremely low-frequency (ELF) magnetic fields on spatial recognition memory in mice by using a two-trial recognition Y-maze that is based on the innate tendency of rodents to explore novel environments. 2. Mice were exposed to 25 or 50 Hz electromagnetic fields for either 7 (short term) or 25 days (long term) and then tested in the Y-maze. 3. The results indicated that neither short- nor long-term exposure to magnetic fields affected the locomotor activity of mice in the Y-maze. However, long-term exposure to 50 Hz fields reduced recognition of the novel arm. 4. Our findings suggest that ELF magnetic fields impair spatial recognition memory in the Y-maze depending on the field strength and/or duration of exposure.

Many types of mazes have been used in cognitive brain research and data obtained from those experiments, especially those from rodents' studies, support the idea that the hippocampus is related to spatial learning and memory. But the results from non-human primates researches regarding the role of the hippocampus in spatial learning and memory are controversial and inconsistent with those obtained in rodents. This might be due to the differences of the methods used in non-human primates and rodents. Several kinds of maze models including two-dimensional computerized visual maze models and three-dimensional maze models have been developed for non-human primates, but they all have some defects. Therefore, development of a maze model for non-human primates that is comparable with those used in rodents is necessary to solve the controversy. This paper describes a large-scale, three-dimensional outdoor maze model for non-human primates which can be used to study spatial learning and memory. Monkeys learn to use the maze quickly compared with two-dimensional computerized visual mazes. It has many advantages which could make up the limits of the existing three-dimensional mazes in non-human primates, and can be comparable with radial arm mazes used in rodents. Based on the results, we believe that the new maze model will be valuable in many research areas, especially in studies involving spatial learning and memory in freely moving monkeys.