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1.
Cells ; 13(14)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39056811

RESUMO

BACKGROUND: Tourette syndrome is a neurodevelopmental movement disorder involving basal ganglia dysfunction. PDE10A inhibitors modulate signaling in the striatal basal ganglia nuclei and are thus of interest as potential therapeutics in treating Tourette syndrome and other movement disorders. METHODS: The preclinical pharmacology and toxicology, human safety and tolerability, and human PET striatal enzyme occupancy data for the PDE10A inhibitor EM-221 are presented. RESULTS: EM-221 inhibited PDE10A with an in vitro IC50 of 9 pM and was >100,000 selective vs. other PDEs and other CNS receptors and enzymes. In rats, at doses of 0.05-0.50 mg/kg, EM-221 reduced hyperlocomotion and the disruption of prepulse inhibition induced by MK-801, attenuated conditioned avoidance, and facilitated novel object recognition, consistent with PDE10A's inhibition. EM-221 displayed no genotoxicity and was well tolerated up to 300 mg/kg in rats and 100 mg/kg in dogs. In single- and multiple-day ascending dose studies in healthy human volunteers, EM-221 was well tolerated up to 10 mg, with a maximum tolerated dose of 15 mg. PET imaging indicated that a PDE10A enzyme occupancy of up to 92.8% was achieved with a ~24 h half-life. CONCLUSIONS: The preclinical and clinical data presented here support the study of EM-221 in phase 2 trials of Tourette syndrome and other movement disorders.


Assuntos
Diester Fosfórico Hidrolases , Síndrome de Tourette , Adulto , Animais , Cães , Feminino , Humanos , Masculino , Ratos , Transtornos dos Movimentos/tratamento farmacológico , Inibidores de Fosfodiesterase/farmacologia , Inibidores de Fosfodiesterase/uso terapêutico , Diester Fosfórico Hidrolases/metabolismo , Tomografia por Emissão de Pósitrons , Ratos Sprague-Dawley , Síndrome de Tourette/tratamento farmacológico , Haplorrinos
2.
Bull Hist Med ; 98(1): 26-60, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881469

RESUMO

Following the medical breakthroughs of Pasteur and Koch after 1880, the use of simians became pivotal to laboratory research to develop vaccines and cultivate microbes through the technique of serial passage. These innovations fueled research on multiple diseases and unleashed a demand for simians, which died easily in captivity. European and American colonial expansion facilitated a burgeoning market for laboratory animals that intensified hunting for live animals. This demand created novel opportunities for disease transfers and viral recombinations as simians of different species were confined in precarious settings. As laboratories moved into the colonies for research into a variety of diseases, notably syphilis, sleeping sickness, and malaria, the simian market was intensified. While researchers expected that colonial laboratories offered more natural environments than their metropolitan affiliates, amassing apes, people, microbes, and insects at close quarters instead created unnatural conditions that may have facilitated the spread of undetectable diseases.


Assuntos
Colonialismo , Animais , História do Século XX , História do Século XIX , Colonialismo/história , Laboratórios/história , Animais de Laboratório , Humanos , Estados Unidos , Haplorrinos , Experimentação Animal/história
3.
Viruses ; 16(6)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38932264

RESUMO

Understanding the underlying mechanisms of HIV pathogenesis is critical for designing successful HIV vaccines and cure strategies. However, achieving this goal is complicated by the virus's direct interactions with immune cells, the induction of persistent reservoirs in the immune system cells, and multiple strategies developed by the virus for immune evasion. Meanwhile, HIV and SIV infections induce a pandysfunction of the immune cell populations, making it difficult to untangle the various concurrent mechanisms of HIV pathogenesis. Over the years, one of the most successful approaches for dissecting the immune correlates of protection in HIV/SIV infection has been the in vivo depletion of various immune cell populations and assessment of the impact of these depletions on the outcome of infection in non-human primate models. Here, we present a detailed analysis of the strategies and results of manipulating SIV pathogenesis through in vivo depletions of key immune cells populations. Although each of these methods has its limitations, they have all contributed to our understanding of key pathogenic pathways in HIV/SIV infection.


Assuntos
Infecções por HIV , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Vírus da Imunodeficiência Símia/imunologia , Vírus da Imunodeficiência Símia/patogenicidade , Animais , Infecções por HIV/imunologia , Infecções por HIV/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Humanos , HIV/imunologia , HIV/patogenicidade , Modelos Animais de Doenças , Haplorrinos , Depleção Linfocítica
5.
Drug Metab Dispos ; 52(8): 765-774, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38811156

RESUMO

Physiologically based pharmacokinetic (PBPK) modeling was used to predict the human pharmacokinetics and drug-drug interaction (DDI) of GDC-2394. PBPK models were developed using in vitro and in vivo data to reflect the oral and intravenous PK profiles of mouse, rat, dog, and monkey. The learnings from preclinical PBPK models were applied to a human PBPK model for prospective human PK predictions. The prospective human PK predictions were within 3-fold of the clinical data from the first-in-human study, which was used to optimize and validate the PBPK model and subsequently used for DDI prediction. Based on the majority of PBPK modeling scenarios using the in vitro CYP3A induction data (mRNA and activity), GDC-2394 was predicted to have no-to-weak induction potential at 900 mg twice daily (BID). Calibration of the induction mRNA and activity data allowed for the convergence of DDI predictions to a narrower range. The plasma concentrations of the 4ß-hydroxycholesterol (4ß-HC) were measured in the multiple ascending dose study to assess the hepatic CYP3A induction risk. There was no change in plasma 4ß-HC concentrations after 7 days of GDC-2394 at 900 mg BID. A dedicated DDI study found that GDC-2394 has no induction effect on midazolam in humans, which was reflected by the totality of predicted DDI scenarios. This work demonstrates the prospective utilization of PBPK for human PK and DDI prediction in early drug development of GDC-2394. PBPK modeling accompanied with CYP3A biomarkers can serve as a strategy to support clinical pharmacology development plans. SIGNIFICANCE STATEMENT: This work presents the application of physiologically based pharmacokinetic modeling for prospective human pharmacokinetic (PK) and drug-drug interaction (DDI) prediction in early drug development. The strategy taken in this report represents a framework to incorporate various approaches including calibration of in vitro induction data and consideration of CYP3A biomarkers to inform on the overall CYP3A-related DDI risk of GDC-2394.


Assuntos
Citocromo P-450 CYP3A , Interações Medicamentosas , Modelos Biológicos , Humanos , Interações Medicamentosas/fisiologia , Citocromo P-450 CYP3A/metabolismo , Animais , Cães , Ratos , Masculino , Camundongos , Biomarcadores/sangue , Biomarcadores/metabolismo , Hidroxicolesteróis/farmacocinética , Hidroxicolesteróis/sangue , Adulto , Feminino , Indutores do Citocromo P-450 CYP3A/farmacocinética , Adulto Jovem , Midazolam/farmacocinética , Midazolam/administração & dosagem , Haplorrinos , Pessoa de Meia-Idade , Estudos Prospectivos
6.
Xenobiotica ; 54(8): 511-520, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38647387

RESUMO

Background: Monomethyl auristatin E (MMAE) has been used as a payload for several Food and Drug Administration (FDA) approved antibody-drug conjugates (ADCs). It is known that MMAE is released from the ADC following binding, internalisation and proteolytic degradation in target tissues. A striking discrepancy in systemic MMAE levels has been observed across species with 50-fold higher MMAE levels in human than that in rodents when normalised by ADC dose with unknown mechanism.Hypothesis and purpose: Multiple factors could affect systemic MMAE levels such as production and elimination of unconjugated MMAE following ADC dosing. In this study, we have explored whether MMAE displays differential red blood cell (RBC) partitioning across species that may contribute to the different MMAE levels seen between human and animals.Experiments: To determine MMAE RBC partitioning, tritium labelled MMAE ([3H]-MMAE) was incubated in whole blood from mice, rats, monkeys and humans in vitro, then RBC partitioning was determined and compared across species. To test whether MMAE released from the ADC would show any difference in RBC partitioning, pinatuzumab vedotin or polatuzumab vedotin was administered to mice, rats, and monkeys. MMAE levels were measured in both blood and plasma, and the ratios of MMAE levels were calculated as blood-to-plasma ratio (in vivo RBC partitioning).Results: Our in vitro data showed that unconjugated MMAE has a species-dependent RBC partitioning with strong RBC partitioning in mouse, rat, followed by monkey blood, whereas minimal RBC partitioning was seen in human blood. Incubation of 2 nM of MMAE in mouse blood resulted in a blood-to-plasma ratio of 11.8 ± 0.291, followed by rat, monkey, and human at 2.36 ± 0.0825, 1.57 ± 0.0250, and 0.976 ± 0.0620, respectively. MMAE RBC partitioning is also concentration-dependent, with an inverse relationship between RBC partitioning and MMAE concentration (higher RBC partitioning at lower concentration). In vivo dosing of pinatuzumab vedotin in mouse displayed systemic MMAE at about a 5-fold higher blood concentration compared to plasma concentration once MMAE reached a pseudo-equilibrium, while systemic MMAE from blood and plasma concentration showed a 1.65-fold difference in rat.Implication and conclusion: These data demonstrated that MMAE has a distinct RBC partitioning across different species, which may contribute to, at least in part, to the differential in the systemic MMAE levels observed in vivo between preclinical and clinical studies. These findings highlight the importance of fully characterising the ADME properties of both the ADC and its payload, to enable better translation from animals to human for ADC development.


Assuntos
Eritrócitos , Imunoconjugados , Oligopeptídeos , Animais , Humanos , Imunoconjugados/farmacocinética , Oligopeptídeos/farmacocinética , Ratos , Eritrócitos/metabolismo , Camundongos , Especificidade da Espécie , Masculino , Macaca fascicularis , Haplorrinos
7.
J Hum Evol ; 190: 103494, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38564844

RESUMO

The body proportions of extant animals help inform inferences about the behaviors of their extinct relatives, but relationships between body proportions, behavior, and phylogeny in extant primates remain unclear. Advances in behavioral data, molecular phylogenies, and multivariate analytical tools make it an opportune time to perform comprehensive comparative analyses of primate traditional limb length proportions (e.g., intermembral, humerofemoral, brachial, and crural indices), body size-adjusted long bone proportions, and principal components. In this study we used a mix of newly-collected and published data to investigate whether and how the limb length proportions of a diverse sample of primates, including monkeys, apes, and modern humans, are influenced by behavior and phylogeny. We reconfirm that the intermembral index, followed by the first principal component of traditional limb length proportions, is the single most effective variable distinguishing hominoids and other anthropoids. Combined limb length proportions and positional behaviors are strongly correlated in extant anthropoid groups, but phylogeny is a better predictor of limb length proportion variation than of behavior. We confirm convergences between members of the Atelidae and extant apes (especially Pan), members of the Hylobatidae and Pongo, and a potential divergence of Presbytis limb proportions from some other cercopithecoids, which correlate with adaptations for forelimb-dominated behaviors in some colobines. Collectively, these results substantiate hypotheses indicating that extinct hominins and other hominoid taxa can be distinguished by analyzing combinations of their limb length proportions at different taxonomic levels. From these results, we hypothesize that fossil skeletons characterized by notably disparate limb length proportions are unlikely to have exhibited similar behavioral patterns.


Assuntos
Hominidae , Hylobatidae , Humanos , Animais , Filogenia , Haplorrinos , Fósseis , Primatas , Extremidade Superior , Evolução Biológica
8.
Front Neural Circuits ; 18: 1389110, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601266

RESUMO

The error-related negativity and an N2-component recorded over medial frontal cortex index core functions of cognitive control. While they are known to originate from agranular frontal areas, the underlying microcircuit mechanisms remain elusive. Most insights about microcircuit function have been derived from variations of the so-called canonical microcircuit model. These microcircuit architectures are based extensively on studies from granular sensory cortical areas in monkeys, cats, and rodents. However, evidence has shown striking cytoarchitectonic differences across species and differences in the functional relationships across cortical layers in agranular compared to granular sensory areas. In this minireview, we outline a tentative microcircuit model underlying cognitive control in the agranular frontal cortex of primates. The model incorporates the main GABAergic interneuron subclasses with specific laminar arrangements and target regions on pyramidal cells. We emphasize the role of layer 5 pyramidal cells in error and conflict detection. We offer several specific questions necessary for creating a specific intrinsic microcircuit model of the agranular frontal cortex.


Assuntos
Lobo Frontal , Macaca , Animais , Lobo Frontal/fisiologia , Células Piramidais , Interneurônios , Haplorrinos , Primatas , Cognição , Córtex Cerebral
10.
Microb Pathog ; 190: 106628, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38508422

RESUMO

Rotavirus infections in suckling and weaning piglets cause severe dehydration and death, resulting in significant economic losses in the pig breeding industry. With the continuous emergence of porcine rotavirus (PoRV) variants and poor vaccine cross-protection among various genotypes, there is an urgent need to develop alternative strategies such as seeking effective antiviral products from nature, microbial metabolites and virus-host protein interaction. Sialidases play a crucial role in various physiopathological processes and offer a promising target for developing antivirus drugs. However, the effect of bacterial-derived sialidases on the infection of PoRVs remains largely unknown. Herein, we investigated the impact of bacterial-derived sialidases (sialidase Cp and Vc) on PoRV strain OSU(Group A) infection, using differentiated epithelial monkey kidney cells (MA104) as a model. Our results indicated that the pretreatment of MA104 with exogenous sialidases effectively suppressed PoRV OSU in a concentration-dependent manner. Notably, even at a concentration of 0.01 µU/mL, sialidases significantly inhibited the virus (MOI = 0.01). Meanwhile, we found that sialidase Vc pretreatment sharply reduced the binding rate of PoRV OSU. Last, we demonstrated that PoRV OSU might recognize α-2,3-linked sialic acid as the primary attachment factor in MA104. Our findings provide new insights into the underlying mechanism of PoRV OSU infections, shedding lights on the development of alternative antivirus approaches based on bacteria-virus interaction.


Assuntos
Neuraminidase , Infecções por Rotavirus , Rotavirus , Replicação Viral , Animais , Neuraminidase/metabolismo , Neuraminidase/genética , Rotavirus/efeitos dos fármacos , Rotavirus/fisiologia , Suínos , Replicação Viral/efeitos dos fármacos , Linhagem Celular , Células Epiteliais/virologia , Células Epiteliais/microbiologia , Ligação Viral/efeitos dos fármacos , Ácido N-Acetilneuramínico/metabolismo , Ácido N-Acetilneuramínico/farmacologia , Antivirais/farmacologia , Haplorrinos , Doenças dos Suínos/virologia , Doenças dos Suínos/microbiologia
11.
J Med Primatol ; 53(2): e12697, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38539278

RESUMO

Balantioides coli (=Balantidium coli), a large ciliated protozoan, is reported in multiple free-ranging and captive primate species, often in association with a clinical presentation that requires medical intervention. This report describes the clinical effectiveness of paromomycin sulfate against B.coli in zoo-kept mandrill monkeys (Mandrillus sphinx, at orally doses of 8-31 mg/kg, once daily (SID) for 7 days) and gorillas (Gorilla gorilla gorilla, at orally doses of 1.4-3.1 mg/kg, SID for 5 days).


Assuntos
Balantidium , Mandrillus , Animais , Paromomicina/farmacologia , Paromomicina/uso terapêutico , Gorilla gorilla , Haplorrinos , Animais de Zoológico
12.
Sci Rep ; 14(1): 6287, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491154

RESUMO

The absence of a natural animal model is one of the main challenges in Alzheimer's disease research. Despite the challenges of using nonhuman primates in studies, these animals can bridge mouse models and humans, as nonhuman primates are phylogenetically closer to humans and can spontaneously develop AD-type pathology. The capuchin monkey, a New World primate, has recently attracted attention due to its skill in creating and using instruments. We analyzed one capuchin brain using structural 7 T MRI and performed a neuropathological evaluation of three animals. Alzheimer-type pathology was found in the two of the capuchins. Widespread ß-amyloid pathology was observed, mainly in focal deposits with variable morphology and a high density of mature plaques. Notably, plaque-associated dystrophic neurites associated with disruption of axonal transport and early cytoskeletal alteration were frequently found. Unlike in other species of New World monkeys, cerebral arterial angiopathy was not the predominant form of ß-amyloid pathology. Additionally, abnormal aggregates of hyperphosphorylated tau, resembling neurofibrillary pathology, were observed in the temporal and frontal cortex. Astrocyte hypertrophy surrounding plaques was found, suggesting a neuroinflammatory response. These findings indicate that aged capuchin monkeys can spontaneously develop Alzheimer-type pathology, indicating that they may be an advantageous animal model for research in Alzheimer's disease.


Assuntos
Doença de Alzheimer , Cebinae , Humanos , Animais , Camundongos , Idoso , Doença de Alzheimer/patologia , Cebus , Haplorrinos , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Placa Amiloide/patologia , Proteínas tau/metabolismo
13.
Neurosci Res ; 201: 46-49, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460842

RESUMO

For animals, including humans, to have self-awareness, the ability to reflect on one's own perceptions and cognitions, which is known as metacognition, and an understanding of consistency of the self from the past to the present and into the future based on metacognition is essential. Through the mediation of self-consciousness, animals are thought to be able to proactively act to change their environment rather than passively responding to changes in their environment. However, it has not been known whether animals have self-awareness, and, if so, how it is implemented neurobiologically. In this review article, I introduce our studies examining the neural basis of metacognitive abilities for past, present, and future actions in macaque monkeys and humans, and explore the evolutionary origins of self-awareness.


Assuntos
Macaca , Metacognição , Animais , Humanos , Haplorrinos , Estudos Retrospectivos , Estudos Prospectivos
14.
Sci Rep ; 14(1): 6450, 2024 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548764

RESUMO

Arithmetic operations are complex mental processes rooted in the abstract concept of numerosity. Despite the significance, the neural architecture responsible for these operations has remained largely uncharted. In this study, we explored the presence of specific neuronal activity in the dorsal premotor cortex of the monkey dedicated to numerical addition and subtraction. Our findings reveal that many of these neural activities undergo a transformation, shifting their coding from arithmetic to motor representations. These motor representations include information about which hand to use and the number of steps involved in the action. We consistently observed that cells related to the right-hand encoded addition, while those linked to the left-hand encoded subtraction, suggesting that arithmetic operations and motor commands are intertwining with each other. Furthermore, we used a multivariate decoding technique to predict the monkey's behaviour based on the activity of these arithmetic-related cells. The classifier trained to discern arithmetic operations, including addition and subtraction, not only predicted the arithmetic decisions but also the subsequent motor actions of the right and left-hand. These findings imply a cognitive extension of the motor cortex's function, where inherent neural systems are repurposed to facilitate arithmetic operations.


Assuntos
Córtex Motor , Animais , Córtex Motor/fisiologia , Haplorrinos , Processos Mentais/fisiologia , Formação de Conceito , Neurônios , Mapeamento Encefálico
15.
Zool Res ; 45(2): 292-298, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38485499

RESUMO

Mutations in mitochondrial DNA (mtDNA) are maternally inherited and have the potential to cause severe disorders. Mitochondrial replacement therapies, including spindle, polar body, and pronuclear transfers, are promising strategies for preventing the hereditary transmission of mtDNA diseases. While pronuclear transfer has been used to generate mitochondrial replacement mouse models and human embryos, its application in non-human primates has not been previously reported. In this study, we successfully generated four healthy cynomolgus monkeys ( Macaca fascicularis) via female pronuclear transfer. These individuals all survived for more than two years and exhibited minimal mtDNA carryover (3.8%-6.7%), as well as relatively stable mtDNA heteroplasmy dynamics during development. The successful establishment of this non-human primate model highlights the considerable potential of pronuclear transfer in reducing the risk of inherited mtDNA diseases and provides a valuable preclinical research model for advancing mitochondrial replacement therapies in humans.


Assuntos
Doenças Mitocondriais , Doenças dos Roedores , Camundongos , Humanos , Feminino , Animais , Doenças Mitocondriais/genética , Doenças Mitocondriais/prevenção & controle , Doenças Mitocondriais/veterinária , Haplorrinos/genética , Mitocôndrias/genética , DNA Mitocondrial/genética , Primatas/genética
16.
PLoS One ; 19(2): e0287893, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324542

RESUMO

Wildlife trafficking creates favorable scenarios for intra- and inter-specific interactions that can lead to parasite spread and disease emergence. Among the fauna affected by this activity, primates are relevant due to their potential to acquire and share zoonoses - infections caused by parasites that can spread between humans and other animals. Though it is known that most primate parasites can affect multiple hosts and that many are zoonotic, comparative studies across different contexts for animal-human interactions are scarce. We conducted a multi-parasite screening targeting the detection of zoonotic infections in wild-caught monkeys in nine Peruvian cities across three contexts: captivity (zoos and rescue centers, n = 187); pet (households, n = 69); and trade (trafficked or recently confiscated, n = 132). We detected 32 parasite taxa including mycobacteria, simian foamyvirus, bacteria, helminths, and protozoa. Monkeys in the trade context had the highest prevalence of hemoparasites (including Plasmodium malariae/brasilianum, Trypanosoma cruzi, and microfilaria) and enteric helminths and protozoa were less common in pet monkeys. However, parasite communities showed overall low variation between the three contexts. Parasite richness (PR) was best explained by host genus and the city where the animal was sampled. Squirrel (genus Saimiri) and wooly (genus Lagothrix) monkeys had the highest PR, which was ~2.2 times the PR found in tufted capuchins (genus Sapajus) and tamarins (genus Saguinus/Leontocebus) in a multivariable model adjusted for context, sex, and age. Our findings illustrate that the threats of wildlife trafficking to One Health encompass exposure to multiple zoonotic parasites well-known to cause disease in humans, monkeys, and other species. We demonstrate these threats continue beyond the markets where wildlife is initially sold; monkeys trafficked for the pet market remain a reservoir for and contribute to the translocation of zoonotic parasites to households and other captive facilities where contact with humans is frequent. Our results have practical applications for the healthcare of rescued monkeys and call for urgent action against wildlife trafficking and ownership of monkeys as pets.


Assuntos
Helmintos , Parasitos , Plasmodium , Humanos , Animais , Peru/epidemiologia , Prevalência , Zoonoses/epidemiologia , Animais Selvagens/microbiologia , Haplorrinos , Saguinus
17.
Eur J Neurosci ; 59(7): 1657-1680, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38414108

RESUMO

The timescales of the dynamics of a system depend on the combination of the timescales of its components and of its transmission delays between components. Here, we combine experimental stimulation data from 10 studies in macaque monkeys that reveal the timing of excitatory and inhibitory events in the basal ganglia circuit, to estimate its set of transmission delays. In doing so, we reveal possible inconsistencies in the existing data, calling for replications, and we propose two possible sets of transmission delays. We then integrate these delays in a model of the primate basal ganglia that does not rely on direct and indirect pathways' segregation and show that extrastriatal dopaminergic depletion in the external part of the globus pallidus and in the subthalamic nucleus is sufficient to generate ß-band oscillations (in the high part, 20-35 Hz, of the band). More specifically, we show that D2 and D5 dopamine receptors in these nuclei play opposing roles in the emergence of these oscillations, thereby explaining how completely deactivating D5 receptors in the subthalamic nucleus can, paradoxically, cancel oscillations.


Assuntos
Dopamina , Núcleo Subtalâmico , Animais , Haplorrinos , Gânglios da Base/fisiologia , Núcleo Subtalâmico/fisiologia , Globo Pálido/fisiologia
18.
Cell ; 187(6): 1476-1489.e21, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38401541

RESUMO

Attention filters sensory inputs to enhance task-relevant information. It is guided by an "attentional template" that represents the stimulus features that are currently relevant. To understand how the brain learns and uses templates, we trained monkeys to perform a visual search task that required them to repeatedly learn new attentional templates. Neural recordings found that templates were represented across the prefrontal and parietal cortex in a structured manner, such that perceptually neighboring templates had similar neural representations. When the task changed, a new attentional template was learned by incrementally shifting the template toward rewarded features. Finally, we found that attentional templates transformed stimulus features into a common value representation that allowed the same decision-making mechanisms to deploy attention, regardless of the identity of the template. Altogether, our results provide insight into the neural mechanisms by which the brain learns to control attention and how attention can be flexibly deployed across tasks.


Assuntos
Atenção , Tomada de Decisões , Aprendizagem , Lobo Parietal , Recompensa , Animais , Haplorrinos
19.
Addict Biol ; 29(2): e13380, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38333998

RESUMO

Humans demonstrate significant behavioural advantages with particular perceptual dimensions (such as colour or shape) and when the relevant dimension is repeated in consecutive trials. These dimension-related behavioural modulations are significantly altered in neuropsychological and addiction disorders; however, their underlying mechanisms remain unclear. Here, we studied whether these behavioural modulations exist in other trichromatic primate species and whether repeated exposure to opioids influences them. In a target detection task where the target-defining dimension (colour or shape) changed trial by trial, humans exhibited shorter response time (RT) and smaller event-related electrodermal activity with colour dimension; however, macaque monkeys had shorter RT with shape dimension. Although the dimensional biases were in the opposite directions, both species were faster when the relevant dimension was repeated, compared with conditions when it changed, across consecutive trials. These indicate that both species formed dimensional sets and that resulted in a significant 'switch cost'. Scheduled and repeated exposures to morphine, which is analogous to its clinical and recreational use, significantly augmented the dimensional bias in monkeys and also changed the switch cost depending on the relevant dimension. These cognitive effects occurred when monkeys were in abstinence periods (not under acute morphine effects) but expressing significant morphine-induced conditioned place preference. These findings indicate that significant dimensional biases and set formation are evolutionarily preserved in humans' and monkeys' cognition and that repeated exposure to morphine interacts with their manifestation. Shared neural mechanisms might be involved in the long-lasting effects of morphine and expression of dimensional biases and set formation in anthropoids.


Assuntos
Analgésicos Opioides , Morfina , Humanos , Animais , Morfina/farmacologia , Haplorrinos , Analgésicos Opioides/farmacologia , Condicionamento Clássico , Cognição
20.
J Vis ; 24(2): 7, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38386341

RESUMO

Studies have shown that duration perception depends on several visual processes. However, the stages of visual processes that contribute to duration perception remain unclear. This study examined the effects of categorical differences in face adaptation on perceived duration. In all the experiments, we compared the perceived durations of human, monkey, and cat faces (comparison stimuli) after adapting to a human face. Results revealed that the human comparison stimuli were perceived shorter than the monkey and cat comparison stimuli (categorical face adaptation on duration perception [CFAD]). The difference between the face categories disappeared when the adapting stimulus was rendered unrecognizable by phase scrambling, indicating that adaptation to low-level visual properties cannot fully account for the CFAD effect. Furthermore, CFAD was preserved but attenuated when the adapting stimulus was inverted or a 1,000-ms interval was inserted before the comparison stimuli, which implied that CFAD occurred as long as the adapting stimulus was perceived as a face and not simply based on conceptual category processes. These findings indicate that face adaptation affects perceived duration in a category-specific manner (the CFAD effect) and highlights the involvement of visual categorical processes in duration perception.


Assuntos
Reconhecimento Facial , Humanos , Animais , Haplorrinos
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