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[PMID]:28404581
[Au] Autor:Sullivan EL; Rivera HM; True CA; Franco JG; Baquero K; Dean TA; Valleau JC; Takahashi DL; Frazee T; Hanna G; Kirigiti MA; Bauman LA; Grove KL; Kievit P
[Ad] Endereço:Division of Neuroscience, Oregon National Primate Research Center, Beaverton, Oregon.
[Ti] Título:Maternal and postnatal high-fat diet consumption programs energy balance and hypothalamic melanocortin signaling in nonhuman primate offspring.
[So] Source:Am J Physiol Regul Integr Comp Physiol;313(2):R169-R179, 2017 Aug 01.
[Is] ISSN:1522-1490
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Maternal high-fat-diet (HFD) consumption during pregnancy decreased fetal body weight and impacted development of hypothalamic melanocortin neural circuitry in nonhuman primate offspring. We investigated whether these impairments during gestation persisted in juvenile offspring and examined the interaction between maternal and early postnatal HFD consumption. Adult dams consumed either a control diet (CTR; 15% calories from fat) or a high-saturated-fat diet (HFD; 37% calories from fat) during pregnancy. Offspring were weaned onto a CTR or HFD at ~8 mo of age. Offspring from HFD-fed dams displayed early catch-up growth and elevated body weight at 6 and 13 mo of age. Maternal and postnatal HFD exposure reduced the amount of agouti-related peptide fibers in the paraventricular nucleus of the hypothalamus. Postnatal HFD consumption also decreased the amount of agouti-related peptide fibers in the arcuate nucleus of the hypothalamus. Postnatal HFD was associated with decreased food intake and increased activity. These results support and extend our previous findings of maternal diet effects on fetal development and reveal, for the first time in a nonhuman primate model, that maternal HFD-induced disturbances in offspring body weight regulation extended past gestation into the juvenile period. Maternal HFD consumption increases the risk for offspring developing obesity, with the developmental timing of HFD exposure differentially impacting the melanocortin system and energy balance regulation. The present findings provide translational insight into human clinical populations, suggesting that profound health consequences may await individuals later in life following intrauterine and postnatal HFD exposure.
[Mh] Termos MeSH primário: Dieta Hiperlipídica/efeitos adversos
Ingestão de Alimentos
Hipotálamo/fisiopatologia
Melanocortinas/metabolismo
Obesidade/fisiopatologia
Efeitos Tardios da Exposição Pré-Natal/fisiopatologia
[Mh] Termos MeSH secundário: Animais
Metabolismo Energético
Comportamento Alimentar
Feminino
Desenvolvimento Fetal
Humanos
Macaca
Masculino
Obesidade/etiologia
Gravidez
Prenhez
Transdução de Sinal
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Melanocortins)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170830
[Lr] Data última revisão:
170830
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170413
[St] Status:MEDLINE
[do] DOI:10.1152/ajpregu.00309.2016


  2 / 16034 MEDLINE  
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[PMID]:28190642
[Au] Autor:Ortiz-Rios M; Azevedo FA; Kusmierek P; Balla DZ; Munk MH; Keliris GA; Logothetis NK; Rauschecker JP
[Ad] Endereço:Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Spemannstraße 36, 72072 Tübingen, Germany; Graduate School of Neural & Behavioural Sciences, International Max Planck Research School (IMPRS), University of Tübingen, Österbergstraße 3, 72074 Tübingen,
[Ti] Título:Widespread and Opponent fMRI Signals Represent Sound Location in Macaque Auditory Cortex.
[So] Source:Neuron;93(4):971-983.e4, 2017 Feb 22.
[Is] ISSN:1097-4199
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In primates, posterior auditory cortical areas are thought to be part of a dorsal auditory pathway that processes spatial information. But how posterior (and other) auditory areas represent acoustic space remains a matter of debate. Here we provide new evidence based on functional magnetic resonance imaging (fMRI) of the macaque indicating that space is predominantly represented by a distributed hemifield code rather than by a local spatial topography. Hemifield tuning in cortical and subcortical regions emerges from an opponent hemispheric pattern of activation and deactivation that depends on the availability of interaural delay cues. Importantly, these opponent signals allow responses in posterior regions to segregate space similarly to a hemifield code representation. Taken together, our results reconcile seemingly contradictory views by showing that the representation of space follows closely a hemifield code and suggest that enhanced posterior-dorsal spatial specificity in primates might emerge from this form of coding.
[Mh] Termos MeSH primário: Córtex Auditivo/fisiologia
Vias Auditivas/fisiologia
Percepção Auditiva/fisiologia
Localização de Som/fisiologia
[Mh] Termos MeSH secundário: Estimulação Acústica/métodos
Animais
Mapeamento Encefálico
Lateralidade Funcional/fisiologia
Macaca
Imagem por Ressonância Magnética/métodos
Som
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170822
[Lr] Data última revisão:
170822
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170213
[St] Status:MEDLINE


  3 / 16034 MEDLINE  
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[PMID]:28159911
[Au] Autor:Confais J; Kim G; Tomatsu S; Takei T; Seki K
[Ad] Endereço:Department of Neurophysiology, National Institute of Neuroscience, Tokyo 187-8502, Japan.
[Ti] Título:Nerve-Specific Input Modulation to Spinal Neurons during a Motor Task in the Monkey.
[So] Source:J Neurosci;37(10):2612-2626, 2017 Mar 08.
[Is] ISSN:1529-2401
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:If not properly regulated, the large amount of reafferent sensory signals generated by our own movement could destabilize the CNS. We investigated how input from peripheral nerves to spinal cord is modulated during behavior. We chronically stimulated the deep radial nerve (DR; proprioceptive, wrist extensors), the median nerve (M; mixed, wrist flexors and palmar skin) and the superficial radial nerve (SR; cutaneous, hand dorsum) while four monkeys performed a delayed wrist flexion-extension task. Spinal neurons putatively receiving direct sensory input were defined based on their evoked response latency following nerve stimulation. We compared the influence of behavior on the evoked response (responsiveness to a specific peripheral input) and firing rate of 128 neuron-nerve pairs based on their source nerve. Firing rate increased during movement regardless of source nerve, whereas evoked response modulation was strikingly nerve-dependent. In SR ( = 47) and M ( = 27) neurons (cutaneous or mixed input), the evoked response was suppressed during wrist flexion and extension. In contrast, in DR neurons ( = 54, pure proprioceptive input), the evoked response was facilitated exclusively during movements corresponding to the contraction of DR spindle-bearing muscles (i.e., wrist extension). Furthermore, modulations of firing rate and evoked response were uncorrelated in SR and M neurons, whereas they tended to be positively comodulated in DR neurons. Our results suggest that proprioceptive and cutaneous inputs to the spinal cord are modulated differently during voluntary movements, suggesting a refined gating mechanism of sensory signals according to behavior. Voluntary movements produce copious sensory signals, which may overwhelm the CNS if not properly regulated. This regulation is called "gating" and occurs at several levels of the CNS. To evaluate the specificity of sensory gating, we investigated how different sources of somatosensory inputs to the spinal cord were modulated while monkeys performed wrist movements. We recorded activity from spinal neurons that putatively received direct connections from peripheral nerves while stimulating their source nerves, and measured the evoked responses. Whereas cutaneous inputs were suppressed regardless of the type of movement, muscular inputs were specifically facilitated during relevant movements. We conclude that, even at the spinal level, sensory gating is a refined and input-specific process.
[Mh] Termos MeSH primário: Retroalimentação Sensorial/fisiologia
Neurônios Motores/fisiologia
Movimento/fisiologia
Nervos Periféricos/fisiologia
Medula Espinal/fisiologia
Análise e Desempenho de Tarefas
[Mh] Termos MeSH secundário: Animais
Macaca
Masculino
Músculo Esquelético/inervação
Músculo Esquelético/fisiologia
Plasticidade Neuronal/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170821
[Lr] Data última revisão:
170821
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170204
[St] Status:MEDLINE
[do] DOI:10.1523/JNEUROSCI.2561-16.2017


  4 / 16034 MEDLINE  
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[PMID]:28742816
[Au] Autor:Hosoya H; Hyvärinen A
[Ad] Endereço:Cognitive Mechanisms Laboratories, ATR International, Kyoto, Japan.
[Ti] Título:A mixture of sparse coding models explaining properties of face neurons related to holistic and parts-based processing.
[So] Source:PLoS Comput Biol;13(7):e1005667, 2017 Jul.
[Is] ISSN:1553-7358
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Experimental studies have revealed evidence of both parts-based and holistic representations of objects and faces in the primate visual system. However, it is still a mystery how such seemingly contradictory types of processing can coexist within a single system. Here, we propose a novel theory called mixture of sparse coding models, inspired by the formation of category-specific subregions in the inferotemporal (IT) cortex. We developed a hierarchical network that constructed a mixture of two sparse coding submodels on top of a simple Gabor analysis. The submodels were each trained with face or non-face object images, which resulted in separate representations of facial parts and object parts. Importantly, evoked neural activities were modeled by Bayesian inference, which had a top-down explaining-away effect that enabled recognition of an individual part to depend strongly on the category of the whole input. We show that this explaining-away effect was indeed crucial for the units in the face submodel to exhibit significant selectivity to face images over object images in a similar way to actual face-selective neurons in the macaque IT cortex. Furthermore, the model explained, qualitatively and quantitatively, several tuning properties to facial features found in the middle patch of face processing in IT as documented by Freiwald, Tsao, and Livingstone (2009). These included, in particular, tuning to only a small number of facial features that were often related to geometrically large parts like face outline and hair, preference and anti-preference of extreme facial features (e.g., very large/small inter-eye distance), and reduction of the gain of feature tuning for partial face stimuli compared to whole face stimuli. Thus, we hypothesize that the coding principle of facial features in the middle patch of face processing in the macaque IT cortex may be closely related to mixture of sparse coding models.
[Mh] Termos MeSH primário: Aprendizagem/fisiologia
Modelos Neurológicos
Neurônios/fisiologia
Reconhecimento Visual de Modelos/fisiologia
[Mh] Termos MeSH secundário: Algoritmos
Animais
Teorema de Bayes
Biologia Computacional
Face/fisiologia
Macaca
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170725
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pcbi.1005667


  5 / 16034 MEDLINE  
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[PMID]:28416597
[Au] Autor:Ponce CR; Lomber SG; Livingstone MS
[Ad] Endereço:Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, and crponce@gmail.com.
[Ti] Título:Posterior Inferotemporal Cortex Cells Use Multiple Input Pathways for Shape Encoding.
[So] Source:J Neurosci;37(19):5019-5034, 2017 May 10.
[Is] ISSN:1529-2401
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In the macaque monkey brain, posterior inferior temporal (PIT) cortex cells contribute to visual object recognition. They receive concurrent inputs from visual areas V4, V3, and V2. We asked how these different anatomical pathways shape PIT response properties by deactivating them while monitoring PIT activity in two male macaques. We found that cooling of V4 or V2|3 did not lead to consistent changes in population excitatory drive; however, population pattern analyses showed that V4-based pathways were more important than V2|3-based pathways. We did not find any image features that predicted decoding accuracy differences between both interventions. Using the HMAX hierarchical model of visual recognition, we found that different groups of simulated "PIT" units with different input histories (lacking "V2|3" or "V4" input) allowed for comparable levels of object-decoding performance and that removing a large fraction of "PIT" activity resulted in similar drops in performance as in the cooling experiments. We conclude that distinct input pathways to PIT relay similar types of shape information, with V1-dependent V4 cells providing more quantitatively useful information for overall encoding than cells in V2 projecting directly to PIT. Convolutional neural networks are the best models of the visual system, but most emphasize input transformations across a serial hierarchy akin to the primary "ventral stream" (V1 → V2 → V4 → IT). However, the ventral stream also comprises parallel "bypass" pathways: V1 also connects to V4, and V2 to IT. To explore the advantages of mixing long and short pathways in the macaque brain, we used cortical cooling to silence inputs to posterior IT and compared the findings with an HMAX model with parallel pathways.
[Mh] Termos MeSH primário: Percepção de Forma/fisiologia
Rede Nervosa/fisiologia
Reconhecimento Visual de Modelos/fisiologia
Lobo Temporal/fisiologia
Córtex Visual/fisiologia
Vias Visuais/fisiologia
[Mh] Termos MeSH secundário: Animais
Macaca
Masculino
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170418
[St] Status:MEDLINE
[do] DOI:10.1523/JNEUROSCI.2674-16.2017


  6 / 16034 MEDLINE  
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[PMID]:28242799
[Au] Autor:Ohmae S; Kunimatsu J; Tanaka M
[Ad] Endereço:Department of Physiology, Hokkaido University School of Medicine, Sapporo 060-8638, Japan, shogo.ohmae@bcm.edu masaki@med.hokudai.ac.jp.
[Ti] Título:Cerebellar Roles in Self-Timing for Sub- and Supra-Second Intervals.
[So] Source:J Neurosci;37(13):3511-3522, 2017 Mar 29.
[Is] ISSN:1529-2401
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Previous studies suggest that the cerebellum and basal ganglia are involved in sub-second and supra-second timing, respectively. To test this hypothesis at the cellular level, we examined the activity of single neurons in the cerebellar dentate nucleus in monkeys performing the oculomotor version of the self-timing task. Animals were trained to report the passage of time of 400, 600, 1200, or 2400 ms following a visual cue by making self-initiated memory-guided saccades. We found a sizeable preparatory neuronal activity before self-timed saccades across delay intervals, while the time course of activity correlated with the trial-by-trial variation of saccade latency in different ways depending on the length of the delay intervals. For the shorter delay intervals, the ramping up of neuronal firing rate started just after the visual cue and the rate of rise of neuronal activity correlated with saccade timing. In contrast, for the longest delay (2400 ms), the preparatory activity started late during the delay period, and its onset time correlated with self-timed saccade latency. Because electrical microstimulation applied to the recording sites during saccade preparation advanced self-timed but not reactive saccades, regardless of their directions, the signals in the cerebellum may have a causal role in self-timing. We suggest that the cerebellum may regulate timing in both sub-second and supra-second ranges, although its relative contribution might be greater for sub-second than for supra-second time intervals. How we decide the timing of self-initiated movement is a fundamental question. According to the prevailing hypothesis, the cerebellum plays a role in monitoring sub-second timing, whereas the basal ganglia are important for supra-second timing. To verify this, we explored neuronal signals in the monkey cerebellum while animals reported the passage of time in the range 400-2400 ms by making eye movements. Contrary to our expectations, we found that neurons in the cerebellar dentate nucleus exhibited a similar preparatory activity for both sub-second and supra-second intervals, and that electrical simulation advanced self-timed saccades in both conditions. We suggest that the cerebellum plays a causal role in the fine adjustment of self-timing in a larger time range than previously thought.
[Mh] Termos MeSH primário: Cerebelo/fisiologia
Sinais (Psicologia)
Fixação Ocular/fisiologia
Tempo de Reação/fisiologia
Movimentos Sacádicos/fisiologia
Percepção do Tempo/fisiologia
[Mh] Termos MeSH secundário: Animais
Feminino
Macaca
Análise e Desempenho de Tarefas
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170228
[St] Status:MEDLINE
[do] DOI:10.1523/JNEUROSCI.2221-16.2017


  7 / 16034 MEDLINE  
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[PMID]:28219983
[Au] Autor:Chaisanguanthum KS; Shen HH; Sabes PN
[Ad] Endereço:Department of Physiology.
[Ti] Título:Neural Representation and Causal Models in Motor Cortex.
[So] Source:J Neurosci;37(12):3413-3424, 2017 Mar 22.
[Is] ISSN:1529-2401
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Dorsal premotor (PMd) and primary motor (M1) cortices play a central role in mapping sensation to movement. Many studies of these areas have focused on correlation-based tuning curves relating neural activity to task or movement parameters, but the link between tuning and movement generation is unclear. We recorded motor preparatory activity from populations of neurons in PMd/M1 as macaque monkeys performed a visually guided reaching task and show that tuning curves for sensory inputs (reach target direction) and motor outputs (initial movement direction) are not typically aligned. We then used a simple, causal model to determine the expected relationship between sensory and motor tuning. The model shows that movement variability is minimized when output neurons (those that directly drive movement) have target and movement tuning that are linearly related across targets and cells. In contrast, for neurons that only affect movement via projections to output neurons, the relationship between target and movement tuning is determined by the pattern of projections to output neurons and may even be uncorrelated, as was observed for the PMd/M1 population as a whole. We therefore determined the relationship between target and movement tuning for subpopulations of cells defined by the temporal duration of their spike waveforms, which may distinguish cell types. We found a strong correlation between target and movement tuning for only a subpopulation of neurons with intermediate spike durations (trough-to-peak ∼350 µs after high-pass filtering), suggesting that these cells have the most direct role in driving motor output. This study focuses on how macaque premotor and primary motor cortices transform sensory inputs into motor outputs. We develop empirical and theoretical links between causal models of this transformation and more traditional, correlation-based "tuning curve" analyses. Contrary to common assumptions, we show that sensory and motor tuning curves for premovement preparatory activity do not generally align. Using a simple causal model, we show that tuning-curve alignment is only expected for output neurons that drive movement. Finally, we identify a physiologically defined subpopulation of neurons with strong tuning-curve alignment, suggesting that it contains a high concentration of output cells. This study demonstrates how analysis of movement variability, combined with simple causal models, can uncover the circuit structure of sensorimotor transformations.
[Mh] Termos MeSH primário: Retroalimentação Sensorial/fisiologia
Modelos Neurológicos
Córtex Motor/fisiologia
Rede Nervosa/fisiologia
Desempenho Psicomotor/fisiologia
Percepção Visual/fisiologia
[Mh] Termos MeSH secundário: Animais
Simulação por Computador
Macaca
Masculino
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170221
[St] Status:MEDLINE
[do] DOI:10.1523/JNEUROSCI.1000-16.2017


  8 / 16034 MEDLINE  
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[PMID]:28112006
[Au] Autor:Lu Y; Tang G; Lin H; Lin X; Jiang L; Yang GY; Wang Y
[Ad] Endereço:a Neuroscience and Neuroengineering Research Center, Med-X Research Institute and School of Biomedical Engineering , Shanghai Jiao Tong University , Shanghai , China.
[Ti] Título:A biosafety evaluation of synchrotron radiation X-ray to skin and bone marrow: single dose irradiation study of rats and macaques.
[So] Source:Int J Radiat Biol;93(6):637-645, 2017 Jun.
[Is] ISSN:1362-3095
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Very limited experimental data is available regarding the safe dosages related to synchrotron radiation (SR) procedures. We used young rats and macaques to address bone marrow and skin tolerance to various doses of synchrotron radiation. METHODS: Rats were subjected to 0, 0.5, 2.5, 5, 25 or 100 Gy local SR X-ray irradiation at left hind limb. Rat blood samples were analyzed at 2-90 days after irradiation. The SR X-ray irradiated skin and tibia were sectioned for morphological examination. For non-human primate study, three male macaques were subjected to 0.5 or 2.5 Gy SR X-ray on crus. Skin responses of macaques were observed. RESULTS: All rats that received SR X-ray irradiation doses greater than 2.5 Gy experienced hair loss and bone-growth inhibition, which were accompanied by decreased number of follicles, thickened epidermal layer, and decreased density of bone marrow cells (p < 0.05). Macaque skin could tolerate 0.5 Gy SR X-ray but showed significant hair loss when the dose was raised above 2.5 Gy. CONCLUSION: The safety threshold doses of SR X-ray for rat skin, bone marrow and macaque skin are between 0.5 and 2.5 Gy. Our study provided essential information regarding the biosafety of SR X-ray irradiation.
[Mh] Termos MeSH primário: Doenças da Medula Óssea/etiologia
Doenças da Medula Óssea/patologia
Medula Óssea/efeitos de radiação
Radiodermatite/etiologia
Radiodermatite/patologia
Pele/efeitos de radiação
Síncrotrons
[Mh] Termos MeSH secundário: Animais
Medula Óssea/patologia
Relação Dose-Resposta à Radiação
Macaca
Masculino
Dose Máxima Tolerável
Dosagem de Radiação
Proteção Radiológica/métodos
Ratos
Ratos Sprague-Dawley
Pele/patologia
Raios X/efeitos adversos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM; S
[Da] Data de entrada para processamento:170123
[St] Status:MEDLINE
[do] DOI:10.1080/09553002.2017.1286049


  9 / 16034 MEDLINE  
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[PMID]:28193685
[Au] Autor:Schomers MR; Garagnani M; Pulvermüller F
[Ad] Endereço:Brain Language Laboratory, Freie Universität Berlin, 14195 Berlin, Germany, malte2011@cantab.net.
[Ti] Título:Neurocomputational Consequences of Evolutionary Connectivity Changes in Perisylvian Language Cortex.
[So] Source:J Neurosci;37(11):3045-3055, 2017 Mar 15.
[Is] ISSN:1529-2401
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The human brain sets itself apart from that of its primate relatives by specific neuroanatomical features, especially the strong linkage of left perisylvian language areas (frontal and temporal cortex) by way of the arcuate fasciculus (AF). AF connectivity has been shown to correlate with verbal working memory-a specifically human trait providing the foundation for language abilities-but a mechanistic explanation of any related causal link between anatomical structure and cognitive function is still missing. Here, we provide a possible explanation and link, by using neurocomputational simulations in neuroanatomically structured models of the perisylvian language cortex. We compare networks mimicking key features of cortical connectivity in monkeys and humans, specifically the presence of relatively stronger higher-order "jumping links" between nonadjacent perisylvian cortical areas in the latter, and demonstrate that the emergence of working memory for syllables and word forms is a functional consequence of this structural evolutionary change. We also show that a mere increase of learning time is not sufficient, but that this specific structural feature, which entails higher connectivity degree of relevant areas and shorter sensorimotor path length, is crucial. These results offer a better understanding of specifically human anatomical features underlying the language faculty and their evolutionary selection advantage. Why do humans have superior language abilities compared to primates? Recently, a uniquely human neuroanatomical feature has been demonstrated in the strength of the arcuate fasciculus (AF), a fiber pathway interlinking the left-hemispheric language areas. Although AF anatomy has been related to linguistic skills, an explanation of how this fiber bundle may support language abilities is still missing. We use neuroanatomically structured computational models to investigate the consequences of evolutionary changes in language area connectivity and demonstrate that the human-specific higher connectivity degree and comparatively shorter sensorimotor path length implicated by the AF entail emergence of verbal working memory, a prerequisite for language learning. These results offer a better understanding of specifically human anatomical features for language and their evolutionary selection advantage.
[Mh] Termos MeSH primário: Evolução Biológica
Córtex Cerebral/fisiologia
Linguagem
Modelos Genéticos
Modelos Neurológicos
Plasticidade Neuronal/genética
[Mh] Termos MeSH secundário: Animais
Aqueduto do Mesencéfalo/fisiologia
Simulação por Computador
Conectoma/métodos
Haplorrinos
Humanos
Macaca
Pan troglodytes
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170214
[St] Status:MEDLINE
[do] DOI:10.1523/JNEUROSCI.2693-16.2017


  10 / 16034 MEDLINE  
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[PMID]:28315649
[Au] Autor:Rapp-Santos KJ; Altamura LA; Norris SL; Lugo-Roman LA; Rico PJ; Hofer CC
[Ad] Endereço:Veterinary Medicine Division,The United States Army Research Institute of Infectious Diseases, Fort Detrick, Maryland;, Email: kamala.j.rappsantos.mil@mail.mil.
[Ti] Título:Comparison of Saliva Collection Methods for the Determination of Salivary Cortisol Levels in Rhesus Macaques ( ), Cynomolgus Macaques ( ), and African Green Monkeys ( ).
[So] Source:J Am Assoc Lab Anim Sci;56(2):181-189, 2017 Mar 01.
[Is] ISSN:1559-6109
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The ability to quickly and accurately determine cortisol as a biomarker for stress is a valuable tool in assessing the wellbeing of NHP. In this study, 2 methods of collecting saliva (a commercial collection device and passive drool) and the resulting free salivary cortisol levels were compared with total serum cortisol concentration in rhesus macaques (Macaca mulatta), cynomolgus macaques (Macaca fascicularis) and African green monkeys (Chlorocebus aethiops) at 2 collection time points. Serum and salivary cortisol levels were determined using a competitive quantitative ELISA. In addition, both saliva collection methods were evaluated for volume collected and ease of use. Compared with passive drool, the experimental collection device was more reliable in collecting sufficient volumes of saliva, and the resulting salivary cortisol values demonstrated stronger correlation with serum cortisol concentration in all species and collection days except cynomolgus macaques on day 1. This saliva collection device allows quick and reliable sample collection for the determination of salivary cortisol levels. In addition, the results might provide a useful tool for evaluating hypothalamic-pituitary-adrenal axis activity or the physiologic stress reaction in NHP as well as a biomarker of psychologic stress states in a variety of situations.
[Mh] Termos MeSH primário: Cercopithecus aethiops/fisiologia
Hidrocortisona/química
Macaca/fisiologia
Saliva/química
Manejo de Espécimes/veterinária
[Mh] Termos MeSH secundário: Animais
Ciência dos Animais de Laboratório
Masculino
Manejo de Espécimes/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
WI4X0X7BPJ (Hydrocortisone)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170816
[Lr] Data última revisão:
170816
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170319
[St] Status:MEDLINE



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