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Neuroimaging and single cell recordings have demonstrated the presence of STS body category-selective regions (body patches) containing neurons responding to presentation of static bodies and body parts. To date, it remains unclear if these body patches and additional STS regions respond during observation of different categories of dynamic actions and to what extent categorization learning influences representations of observed actions in the STS. In the present study, we trained monkeys to discriminate videos depicting three different actions categories (grasping, touching and reaching) with a forced-choice action categorization task. Before and after categorization training, we performed fMRI recordings while monkeys passively observed the same action videos. At the behavioral level, after categorization training, monkeys generalized to untrained action exemplars, in particular for grasping actions. Before training, uni- and/or multivariate fMRI analyses suggest a broad representation of dynamic action categories in particular in posterior and middle STS. Univariate analysis further suggested action category specific training effects in middle and anterior body patches, face patch ML and posterior STS region MT and FST. Overall, our fMRI experiments suggest a widespread representation of observed dynamic bodily actions in the STS that can be modulated by visual learning, supporting its proposed role in action recognition.
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Mapeo Encefálico , Macaca , Animales , Reconocimiento en Psicología/fisiología , Imagen por Resonancia Magnética/métodos , Estimulación Luminosa/métodos , Aprendizaje EspacialRESUMEN
Confinement effects in highly porous nanostructures can effectively adjust the selectivity and kinetics of electrochemical reactions, which can boost the methanol oxidation reaction (MOR). In this work, carbonized ZIF-8-confined hollow PtCo nanospheres (PtCo@carbonized ZIF-8) were fabricated using a facile strategy. A monodisperse confined region was successfully prepared, and the dispersion of the PtCo nanoparticles (NPs) could be precisely regulated, allowing for the effective tuning of the confined region. Thus, the precise regulation of the catalytic reaction was achieved. Importantly, hollow PtCo NPs were prepared using a method based on the Kirkendall effect, and their forming mechanism was systematically investigated. Because of the confinement effects of carbonized zeolitic imidazolate framework-8 (ZIF-8), the crystal and electronic structures of the PtCo NPs were able to be effectively tuned. Our electrochemical results show that PtCo@carbonized ZIF-8 composites manifest a higher mass activity (1.4 A mgPt-1) and better stability compared to commercial Pt/C.
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Human speech production requires the ability to couple motor actions with their auditory consequences. Nonhuman primates might not have speech because they lack this ability. To address this question, we trained macaques to perform an auditory-motor task producing sound sequences via hand presses on a newly designed device ("monkey piano"). Catch trials were interspersed to ascertain the monkeys were listening to the sounds they produced. Functional MRI was then used to map brain activity while the animals listened attentively to the sound sequences they had learned to produce and to two control sequences, which were either completely unfamiliar or familiar through passive exposure only. All sounds activated auditory midbrain and cortex, but listening to the sequences that were learned by self-production additionally activated the putamen and the hand and arm regions of motor cortex. These results indicate that, in principle, monkeys are capable of forming internal models linking sound perception and production in motor regions of the brain, so this ability is not special to speech in humans. However, the coupling of sounds and actions in nonhuman primates (and the availability of an internal model supporting it) seems not to extend to the upper vocal tract, that is, the supralaryngeal articulators, which are key for the production of speech sounds in humans. The origin of speech may have required the evolution of a "command apparatus" similar to the control of the hand, which was crucial for the evolution of tool use.
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Percepción Auditiva/fisiología , Aprendizaje , Macaca mulatta/fisiología , Corteza Motora/fisiología , Sonido , Animales , Mapeo Encefálico , Potenciales Evocados Auditivos , Femenino , Imagen por Resonancia Magnética , MasculinoRESUMEN
Triclosan (TCS) is omnipresent in the environment and has drawn increasing attention due to its potential adverse effects on human health. Direct photolysis of TCS readily occurs, especially in the surface layers of waters that receive abundant ultraviolet radiation during the daytime. However, biological concerns and the identification of toxic products during TCS photolysis have been explored limitedly. Therefore, in the present work, the structural characterization of the photolysis products by UVC and UVA were performed based on the mass spectra and fragmental ions. The results displayed that TCS was more readily eliminated by UVC than UVA, and the product species were completely different when TCS was degraded by UVC and UVA, respectively. Two products, m/z 235 and m/z 252, were produced via reductive dechlorination and nucleophilic substitution with UVC, while three dioxin-like isomer products were generated by dechlorination, cyclization and hydroxylation. Furthermore, the results of biological concerns suggested that the elimination of TCS did not represent the disappearance of biological risks. Specifically, more hazardous and photolysis products were formed during TCS photolysis with ultraviolets. For instance, the dioxin-like isomer products were highly microtoxic and genotoxic, and mildly antiestrogenic. The positive findings highlighted the biological concerns of TCS photolysis by ultraviolet radiation in the aquatic environment.
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Dioxinas , Triclosán , Contaminantes Químicos del Agua , Humanos , Triclosán/metabolismo , Rayos Ultravioleta , Fotólisis , Espectrometría de Masas , Contaminantes Químicos del Agua/análisisRESUMEN
While brain research over the past decades has shed light on the neural correlates of social cognition and behavior in human and non-human primates, most of this research has been performed in virtual settings requiring subjects to observe pictures or recorded videos instead of observing or interacting with another real-live individual. Here we present a two-monkey fMRI setup, allowing examining whole brain responses in macaque monkeys while they observe or interact face-to-face with another real-live conspecific. We tested this setup by comparing overall brain responses during observation of conspecific hand actions in a virtual (observation of recorded videos of actions) or live context (observation of a real-live conspecific performing actions). This dyadic monkey fMRI setup allows examining brain-wide responses in macaque monkeys during different aspects of social behavior, including observation of real-live actions and sensations, social facilitation, joint-attention and social interactions.
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Imagen por Resonancia Magnética , Cognición Social , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Humanos , Macaca mulatta , Conducta SocialRESUMEN
In primates, faces and bodies activate distinct regions in the inferior temporal (IT) cortex and are typically studied separately. Yet, primates interact with whole agents and not with random concatenations of faces and bodies. Despite its social importance, it is still poorly understood how faces and bodies interact in IT. Here, we addressed this gap by measuring fMRI activations to whole agents and to unnatural face-body configurations in which the head was mislocated with respect to the body, and examined how these relate to the sum of the activations to their corresponding faces and bodies. First, we mapped patches in the IT of awake macaques that were activated more by images of whole monkeys compared to objects and found that these mostly overlapped with body and face patches. In a second fMRI experiment, we obtained no evidence for superadditive responses in these "monkey patches", with the activation to the monkeys being less or equal to the summed face-body activations. However, monkey patches in the anterior IT were activated more by natural compared to unnatural configurations. The stronger activations to natural configurations could not be explained by the summed face-body activations. These univariate results were supported by regression analyses in which we modeled the activations to both configurations as a weighted linear combination of the activations to the faces and bodies, showing higher regression coefficients for the natural compared to the unnatural configurations. Deeper layers of trained convolutional neural networks also contained units that responded more to natural compared to unnatural monkey configurations. Unlike the monkey fMRI patches, these units showed substantial superadditive responses to the natural configurations. Our monkey fMRI data suggest configuration-sensitive face-body interactions in anterior IT, adding to the evidence for an integrated face-body processing in the primate ventral visual stream, and open the way for mechanistic studies using single unit recordings in these patches.
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Mapeo Encefálico , Reconocimiento Visual de Modelos , Animales , Mapeo Encefálico/métodos , Reconocimiento Visual de Modelos/fisiología , Estimulación Luminosa/métodos , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiología , Imagen por Resonancia Magnética/métodos , MacacaRESUMEN
While mirror neurons have been found in several monkey brain regions, their existence in the human brain is still largely inferred from indirect non-invasive measurements like functional MRI. It has been proposed that, beyond showing overlapping brain responses during action observation and execution tasks, candidate mirror neuron regions should demonstrate cross-modal action specificity, in line with a defining physiological characteristic of these neurons in the monkey brain. Although cross-modal fMRI adaptation has been put forward as a suited method to test this key feature of cross-modal action specificity in the human brain, so far, the overall usefulness of this technique to demonstrate mirror neuron activity remains unclear. To date, it has never been tested to what extent monkey brain regions known to house mirror neurons, would yield uni- and/or cross-modal fMRI adaptation effects. We therefore performed an fMRI adaptation experiment while male rhesus macaques either performed or observed two different goal-directed hand actions. Executing grasp/lift or touch/press actions in the dark, as well as observing videos of these monkey hand actions, yielded robust responses throughout the brain, including overlapping fMRI responses in parietal and premotor mirror neuron regions. Uni-modal adaptation effects were mostly restricted to the visual modality and the early visual cortices. Both frequentist and Bayesian statistical analyses however suggested no evidence for cross-modal fMRI adaptation effects in monkey parietal and premotor mirror neuron regions. Overall, these findings suggest monkey mirror neuron activity does not readily translate into cross-modal repetition suppression effects that can be detected by fMRI.
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Adaptación Fisiológica/fisiología , Encéfalo/fisiología , Imagen por Resonancia Magnética/métodos , Estimulación Luminosa/métodos , Desempeño Psicomotor/fisiología , Percepción Visual/fisiología , Animales , Encéfalo/diagnóstico por imagen , Macaca mulatta , Masculino , Neuronas Espejo/fisiologíaRESUMEN
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.
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Envejecimiento/fisiología , Visión Ocular/fisiología , Percepción Visual/fisiología , Adulto , Anciano , Análisis de Varianza , Sensibilidad de Contraste/fisiología , Discriminación en Psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Orientación Espacial/fisiología , Reconocimiento Visual de Modelos/fisiología , Estimulación Luminosa/métodos , Adulto JovenRESUMEN
The dynamic characteristics of the cavity mirror support structure strongly influence the quality of the output beam. However, the contradiction between excellent dynamic performance and light weight make the design process challenging. To cope with the problems encountered in the original design of a chemical oxygen iodine laser system, this paper presents a two-dimensional adjustable support structure based on spherical constraints with large specific stiffness in the initial design phase. Subsequently, a two-level optimization strategy containing a macro design and a detailed design is adopted to optimize the initial structure. At the macro design stage, a two-step topology optimization procedure is introduced, in which the scale of the optimization model is dramatically reduced using the independent continuous mapping algorithm to improve the calculation speed in the first step, and the gray elements are eliminated using the bi-directional evolutionary structural optimization method to clearly obtain the optimal topology in the second step. This method is verified to overcome the defect of low efficiency, while still eliminating gray elements. At the detailed design stage, an adaptive surrogate model and the multi-objective design optimization method are employed to seek the best compromise between the lower weight and higher dynamic performance. The results from the application to the example of the cavity mirror support structure show that the mass is reduced by 41.8%, and the dynamic performance requirement is fulfilled.
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A standardized preparation process is proposed in this study for achieving optimal strength and vegetative properties in vegetated concrete, using Yunnan red soil as a growth substrate for plants. The porosity of vegetated concrete is a crucial factor influencing plant growth, while compressive strength is a significant mechanical property. To assess the strength and porosity of vegetated concrete, different design porosities (22%, 24%, 26%, 28%) and cement-to-aggregate ratios (4, 5, 6, 7) were utilized in the preparation of vegetated concrete samples. The shell-making and static-pressure-molding methods were optimized for specimen preparation. Analyzing the stress-strain full curve characteristics of vegetation-type concrete under different influencing factors, an in-depth investigation into its failure mechanism was conducted. It was determined that the design porosity and cement content significantly impact the concrete's performance, particularly in terms of 30-day compressive strength and effective porosity. Furthermore, an increase in the fly ash ratio led to an increase in porosity and a decrease in compressive strength, providing a certain guidance for optimizing concrete performance. Comparative analysis through vegetation experiments revealed that black rye grass exhibited favorable growth adaptability compared to other grass species.
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BACKGROUND: Endometriosis is a benign gynaecological disease with malignant characteristics that severely affects women's quality of life. Long noncoding RNA maternally expressed gene 3 (LncRNA MEG3) is a tumour suppressor that is downregulated in various cancer cells and tissues, and regulates multiple biological processes. Emerging studies have revealed that the interactions between MEG3 and proteins are involved in disease progression. Galectin-1 affects cell motility, signal transduction and vascularization, and is overexpressed in endometriosis. Our study is the first to explore the role of MEG3-210 transcript in endometriosis and to reveal the regulatory mechanism mediated by the interaction between MEG3-210 and Galectin-1. MATERIALS AND METHODS: Endometrial tissues and sera from patients with endometriosis and controls were collected. qRT-PCR was performed to detect the expression of MEG3-210 in the endometrium and endometrial stromal cells (ESCs). The CCK-8 assay, the Transwell assay, flow cytometry and animal models were conducted to evaluate the functions of MEG3-210 in vitro and in vivo. Bioinformatic analysis, Western blot assays, RNA-pull down assays and RNA immunoprecipitation were used to explore the potential mechanism of MEG3-210 in endometriosis. RESULTS: Our results showed that MEG3-210 expression was lower in the eutopic endometrium of women with endometriosis. MEG3-210 downregulation promoted ESCs migration, invasion, anti-apoptosis in vitro and growth of endometriotic lesions in vivo. Furthermore, MEG3-210 downregulation could activate p38 mitogen-activated protein kinase (p38 MAPK) and inhibit cAMP-dependent protein kinase A/sarcoplasmic reticulum Ca2+ ATPase 2 (PKA/SERCA2) signalling, which was mediated by Galectin-1. The protein levels of Galectin-1 in patients with endometriosis were elevated, and Galectin-1 siRNA could reduce the size of lesions. CONCLUSION: MEG3-210 regulates ESCs through p38 MAPK and PKA/SERCA signalling via interaction with Galectin-1. The novel regulatory mechanism may provide new insights into drug therapy and the diagnosis of endometriosis.
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Endometriosis/genética , Endometrio/fisiología , Galectina 1/metabolismo , Enfermedades Peritoneales/genética , ARN Largo no Codificante/fisiología , Células del Estroma/fisiología , Adulto , Apoptosis/genética , Adhesión Celular/genética , Movimiento Celular/genética , Células Cultivadas , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Endometriosis/metabolismo , Endometriosis/patología , Endometrio/citología , Endometrio/patología , Femenino , Humanos , Enfermedades Peritoneales/metabolismo , Enfermedades Peritoneales/patología , Unión Proteica , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Transducción de Señal/genética , Células del Estroma/patología , Migración Transcelular de la Célula/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
The purpose of this study was to integrate the existing expression profile data on endometriosis (EM)-related tissues in order to identify the differentially expressed genes. In this study, three series of raw expression data were downloaded from GEO database. Differentially expressed genes (DEGs) in three tissue types were screened. GO, KEGG pathway enrichment analysis, core differential genes (CDGs) protein-protein interaction (PPI) network and weighted gene co-expression network analysis (WGCNA) were performed, finally, the dysregulation of Hippo pathway in ectopic endometrium (EC) was detected by Western blotting. A total of 1,811 DEGs between eutopic (EU) and normal endometrium (NE), 5,947 DEGs between EC and EU, and 3,192 DEGs between EC and NE datasets were identified. After screening, 394 CDGs were obtained, and 5 hub genes identified in the PPI network. CDGs enrichment and WGCNA network analysis revealed cell proliferation, differentiation, migration and other biological processes, Hippo and Wnt signaling pathways, and a variety of tumor-related pathways. Western blotting results showed that YAP/TAZ was upregulated, and MOB1, pMOB1, SAV1, LATS1 and LATS2 were downregulated in EC. Moreover, CDGs, especially the hub genes, are potential biomarkers and therapeutic targets. Finally, the Hippo pathway might play a key role in the development of endometriosis.
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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.
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Vías Nerviosas , Estimulación Luminosa/métodos , Lóbulo Temporal , Percepción Visual/fisiología , Adulto , Mapeo Encefálico/métodos , Femenino , Voluntarios Sanos , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiologíaRESUMEN
Endometriosis is a common gynecological condition with unclear pathogenesis. Although a dysregulated lncRNA expression profile has been speculated, very few studies have addressed this hypothesis. We determined the differential lncRNA and mRNA expression patterns between endometriosis and control tissues, and between eutopic and normal endometrium in the proliferative phase, using RNA sequencing. The potential targets of lncRNA were predicted on the basis of cis and trans action, and lncRNAs were functionally annotated in relation to their co-expressed mRNAs. Dysregulated lncRNAs and mRNAs were screened relative to the biological features of endometriosis, and the five filtered lncRNAs were validated using qRT-PCR. A total of 9924 novel lncRNA transcripts were identified, and 86 lncRNAs and 1228 mRNAs were differentially expressed between the endometriosis and control groups. GO and KEGG pathway analysis showed that the differentially expressed lncRNAs were enriched in the biological processes and signaling pathways involved in endometriosis. A coding-noncoding gene (CNC) co-expression network was constructed using the dysregulated lncRNAs and their co-expressed mRNAs to simulate the complex intergenic interactions. This study is the first to use sequencing technology to elucidate the differentially lncRNA expression profiles of eutopic and normal endometrium in the proliferative phase of endometriosis. The dysregulated lncRNAs can potentially be novel diagnostic biomarkers and therapeutic targets of endometriosis.
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Endometriosis/metabolismo , Perfilación de la Expresión Génica , Ovario/metabolismo , ARN Largo no Codificante/genética , Adulto , Biomarcadores/metabolismo , Femenino , Regulación de la Expresión Génica , Biblioteca de Genes , Redes Reguladoras de Genes , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , Análisis de Secuencia de ARN , Transducción de SeñalRESUMEN
A common pattern in dominance hierarchies is that some ranks result in higher levels of psychosocial stress than others. Such stress can lead to negative health outcomes, possibly through altered levels of stress hormones. The dominance rank-stress physiology relationship is known to vary between species; sometimes dominants show higher levels of glucocorticoid stress hormones, whereas in other cases subordinates show higher levels. It is less clear how this relationship varies between groups of different ages or cultures. In this study, we used long-term cortisol measurement methods to compare the effect of rank on cortisol levels in adult and adolescent male rhesus macaques. In the adult groups, subordinates had significantly higher cortisol levels. In the adolescents, no significant correlation between cortisol and status was found. Further analysis demonstrated that the adult hierarchy was stricter than that of the adolescents. Adult subordinates received extreme aggression more frequently than dominants, and this class of behavior was positively correlated with cortisol; by contrast, adolescents showed neither trend. Together, these findings provide evidence for a cortisol-rank relationship determined by social factors, namely, despotism of the group, and highlight the importance of group-specific social analysis when comparing or combining results obtained from different groups of animals.
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Hidrocortisona/análisis , Macaca mulatta/metabolismo , Estrés Psicológico/metabolismo , Factores de Edad , Agresión , Animales , Conducta Animal , Masculino , Predominio SocialRESUMEN
Stress from dominance ranks in human societies, or that of other social animals, especially nonhuman primates, can have negative influences on health. Individuals holding different social status may be burdened with various stress levels. The middle class experiences a special stress situation within the dominance hierarchy due to its position between the higher and lower classes. Behaviorally, questions about where middle-class stress comes from and how individuals adapt to middle-class stress remain poorly understood in nonhuman primates. In the present study, social interactions, including aggression, avoidance, grooming and mounting behaviors, between beta males, as well as among group members holding higher or lower social status, were analyzed in captive male-only cynomolgus monkey groups. We found that aggressive tension from the higher hierarchy members was the main origin of stress for middle-class individuals. However, behaviors such as attacking lower hierarchy members immediately after being the recipient of aggression, as well as increased avoidance, grooming and mounting toward both higher and lower hierarchy members helped alleviate middle-class stress and were particular adaptations to middle-class social status.
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Macaca fascicularis/psicología , Estrés Psicológico , Agresión , Animales , Conducta Animal , Femenino , Macaca fascicularis/fisiología , Masculino , Conducta Social , Predominio SocialRESUMEN
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.
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Modelos Animales de Enfermedad , Corteza Prefrontal/fisiopatología , Esquizofrenia/patología , Esquizofrenia/fisiopatología , Animales , Antipsicóticos/uso terapéutico , Trastornos del Conocimiento , Antagonistas de Aminoácidos Excitadores/toxicidad , Haplorrinos , Fenciclidina/toxicidad , Corteza Prefrontal/patología , Desempeño Psicomotor , Esquizofrenia/inducido químicamente , Esquizofrenia/tratamiento farmacológicoRESUMEN
[This corrects the article on p. 171 in vol. 8, PMID: 25610392.].
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Visual recognition is a computational challenge that is thought to occur via efficient coding. An important concept is sparseness, a measure of coding efficiency. The prevailing view is that sparseness supports efficiency by minimizing redundancy and correlations in spiking populations. Yet, we recently reported that "choristers", neurons that behave more similarly (have correlated stimulus preferences and spontaneous coincident spiking), carry more generalizable object information than uncorrelated neurons ("soloists") in macaque inferior temporal (IT) cortex. The rarity of choristers (as low as 6% of IT neurons) indicates that they were likely missed in previous studies. Here, we report that correlation strength is distinct from sparseness (choristers are not simply broadly tuned neurons), that choristers are located in non-granular output layers, and that correlated activity predicts human visual search efficiency. These counterintuitive results suggest that a redundant correlational structure supports efficient processing and behavior.