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1.
Behav Brain Sci ; 46: e266, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37766633

RESUMO

Language-of-thought hypothesis (LoTH) is having a profound impact on cognition studies. However, much remains unknown about its basic primitives and generative operations. Infant studies are fundamental, but methodologically very challenging. By distilling potential primitives from work in natural-language semantics, an approach beyond the corset of standard formal logic may be undertaken. Still, the road ahead is challenging and long.


Assuntos
Idioma , Lógica , Humanos , Cognição , Semântica , Ciência Cognitiva
2.
Dev Sci ; 18(2): 183-93, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25040752

RESUMO

Recent research shows that preverbal infants can reason about single-case probabilities without relying on observed frequencies, adapting their predictions to relevant dynamic parameters of the situation (Téglás, Vul, Girotto, Gonzalez, Tenenbaum & Bonatti, ; Téglás, Girotto, Gonzalez & Bonatti, ). Here we show that intuitions of probabilities may derive from the ability to represent a limited number of possibilities. After watching a scene containing moving objects of two ensembles, 12-month-olds looked longer at an unlikely than at a likely single-case outcome when the objects were within the parallel individuation range. However, they did not do so when the scene contained the same ratio between ensembles but a larger number of objects. At the same time, they could form rational expectations about single-case outcomes in scenes containing the same large number of objects when they could exploit subtle physical parameters induced by the objects' movements and their spatial configuration. Our findings demonstrate that at early stages of development the mental representations involved in probability estimations of future individual situations are powerful and sophisticated, but at the same time they depend on infants' overall cognitive architecture, being constrained by the numerical representations spontaneously induced by the situations.


Assuntos
Desenvolvimento Infantil/fisiologia , Percepção de Profundidade/fisiologia , Intuição/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Probabilidade , Análise de Variância , Feminino , Humanos , Lactente , Masculino , Percepção de Movimento , Estimulação Luminosa , Tempo de Reação/fisiologia
3.
J Child Lang ; 42(4): 873-902, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25300736

RESUMO

To achieve language proficiency, infants must find the building blocks of speech and master the rules governing their legal combinations. However, these problems are linked: words are also built according to rules. Here, we explored early morphosyntactic sensitivity by testing when and how infants could find either words or within-word structure in artificial speech snippets embodying properties of morphological constructions. We show that 12-month-olds use statistical relationships between syllables to extract words from continuous streams, but find word-internal regularities only if the streams are segmented. Seven-month-olds fail both tasks. Thus, 12-month-olds infants possess the resources to analyze the internal composition of words if the speech contains segmentation information. However, 7-month-old infants may not possess them, although they can track several statistical relations. This developmental difference suggests that morphosyntactic sensitivity may require computational resources extending beyond the detection of simple statistics.


Assuntos
Lactente , Desenvolvimento da Linguagem , Linguística , Humanos , Aprendizagem , Percepção da Fala
4.
Cogn Psychol ; 67(3): 130-50, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24041871

RESUMO

In order to acquire language, infants must extract its building blocks-words-and master the rules governing their legal combinations from speech. These two problems are not independent, however: words also have internal structure. Thus, infants must extract two kinds of information from the same speech input. They must find the actual words of their language. Furthermore, they must identify its possible words, that is, the sequences of sounds that, being morphologically well formed, could be words. Here, we show that infants' sensitivity to possible words appears to be more primitive and fundamental than their ability to find actual words. We expose 12- and 18-month-old infants to an artificial language containing a conflict between statistically coherent and structurally coherent items. We show that 18-month-olds can extract possible words when the familiarization stream contains marks of segmentation, but cannot do so when the stream is continuous. Yet, they can find actual words from a continuous stream by computing statistical relationships among syllables. By contrast, 12-month-olds can find possible words when familiarized with a segmented stream, but seem unable to extract statistically coherent items from a continuous stream that contains minimal conflicts between statistical and structural information. These results suggest that sensitivity to word structure is in place earlier than the ability to analyze distributional information. The ability to compute nontrivial statistical relationships becomes fully effective relatively late in development, when infants have already acquired a considerable amount of linguistic knowledge. Thus, mechanisms for structure extraction that do not rely on extensive sampling of the input are likely to have a much larger role in language acquisition than general-purpose statistical abilities.


Assuntos
Linguagem Infantil , Vocabulário , Estimulação Acústica , Fatores Etários , Desenvolvimento Infantil , Feminino , Humanos , Lactente , Masculino , Fala
5.
J Chem Theory Comput ; 19(12): 3616-3633, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37278989

RESUMO

We present quantum mechanics (QM)/frequency dependent fluctuating charge (QM/ωFQ) and fluctuating dipoles (QM/ωFQFµ) multiscale approaches to model surface-enhanced Raman scattering spectra of molecular systems adsorbed on plasmonic nanostructures. The methods are based on a QM/classical partitioning of the system, where the plasmonic substrate is treated by means of the atomistic electromagnetic models ωFQ and ωFQFµ, which are able to describe in a unique fashion and at the same level of accuracy the plasmonic properties of noble metal nanostructures and graphene-based materials. Such methods are based on classical physics, i.e. Drude conduction theory, classical electrodynamics, and atomistic polarizability to account for interband transitions, by also including an ad-hoc phenomenological correction to describe quantum tunneling. QM/ωFQ and QM/ωFQFµ are thus applied to selected test cases, for which computed results are compared with available experiments, showing the robustness and reliability of both approaches.

6.
Curr Biol ; 33(18): 4014-4020.e5, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37659416

RESUMO

The origins of the human capacity for logically structured thought are still a mystery. Studies on young humans, which can be particularly informative, present conflicting results. Infants seem able to generate competing hypotheses1,2,3 and monitor the certainty or probability of one-shot outcomes,4,5,6,7,8 suggesting the existence of an articulated language of thought.9 However, sometimes toddlers10 and even children younger than 411,12,13,14 fail tasks seemingly requiring the same representational abilities. One fundamental test for the presence of logical abilities is the concept of disjunction as a way into the conception of alternative possibilities, and of disjunctive elimination as a way to prune them. Here, we document their widespread presence in 19-month-old infants. In a word-referent association task, both bilingual and monolingual infants display a pattern of oculomotor inspection previously found to be a hallmark of disjunctive reasoning in adults and children,15,16 showing that the onset of logical reasoning is not crucially dependent on language experience. The pattern appears when targets are novel, but also when both objects and words are known, though likely not yet sedimented into a mature lexicon. Disjunctive reasoning also surfaces in a non-linguistic location search task, not prompted by violated expectations, showing that infants reason by elimination spontaneously. Together, these results help answer long-standing empirical and philosophical puzzles about the role of logic in early knowledge development, suggesting that by increasing confidence in some options while eliminating alternatives, logic provides scaffolding for the organization of knowledge about the world, language, and language-world relations.


Assuntos
Cognição , Idioma , Adulto , Humanos , Lactente , Resolução de Problemas , Lógica , Conhecimento
7.
Sci Rep ; 13(1): 2341, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36759690

RESUMO

We often express our thoughts through words, but thinking goes well beyond language. Here we focus on an elementary but basic thinking process, disjunction elimination, elicited by elementary visual scenes deprived of linguistic content, describing its neural and oculomotor correlates. We track two main components of a nonverbal deductive process: the construction of a logical representation (A or B), and its simplification by deduction (not A, therefore B). We identify the network active in the two phases and show that in the latter, but not in the former, it overlaps with areas known to respond to verbal logical reasoning. Oculomotor markers consistently differentiate logical processing induced by the construction of a representation, its simplification by deductive inference, and its maintenance when inferences cannot be drawn. Our results reveal how integrative logical processes incorporate novel experience in the flow of thoughts induced by visual scenes.


Assuntos
Encéfalo , Resolução de Problemas , Idioma , Lógica , Mapeamento Encefálico
8.
ACS Photonics ; 10(2): 394-400, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36820323

RESUMO

Terahertz spectroscopy is a perfect tool to investigate the electronic intraband conductivity of graphene, but a phenomenological model (Drude-Smith) is often needed to describe disorder. By studying the THz response of isotropically strained polycrystalline graphene and using a fully atomistic computational approach to fit the results, we demonstrate here the connection between the Drude-Smith parameters and the microscopic behavior. Importantly, we clearly show that the strain-induced changes in the conductivity originate mainly from the increased separation between the single-crystal grains, leading to enchanced localization of the plasmon excitations. Only at the lowest strain values explored, a behavior consistent with the deformation of the individual grains can instead be observed.

9.
Neuroimage ; 59(2): 1752-64, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-21888981

RESUMO

Deduction is the ability to draw necessary conclusions from previous knowledge. Here we propose a novel approach to understanding the neural basis of deduction, which exploits fine-grained inter-participant variability in such tasks. Participants solved deductive problems and were grouped by the behavioral strategies employed, i.e., whether they were sensitive to the logical form of syllogistic premises, whether the problems were solved correctly, and whether heuristic strategies were employed. Differential profiles of neural activity can predict membership of the first two of these groups. The predictive power of activity profiles is distributed non-uniformly across the brain areas activated by deduction. Activation in left ventro-lateral frontal (BA47) and lateral occipital (BA19) cortices predicts whether logically valid solutions are sought. Activation of left inferior lateral frontal (BA44/45) and superior medial frontal (BA6/8) cortices predicts sensitivity to the logical structure of problems. No specific pattern of activation was associated with the use of a non-logical heuristic strategy. Not only do these findings corroborate the hypothesis that left BA47, BA44/45 and BA6/8 are critical for making syllogistic deductions, but they also imply that they have different functional roles as components of a dedicated network. We propose that BA44/45 and BA6/8 are involved in the extraction and representation of the formal structure of a problem, while BA47 is involved in the selection and application of relevant inferential rules. Finally, our findings suggest that deductive reasoning can be best described as a cascade of cognitive processes requiring the concerted operation of several, functionally distinct, brain areas.


Assuntos
Córtex Cerebral/fisiologia , Tomada de Decisões/fisiologia , Função Executiva/fisiologia , Rede Nervosa/fisiologia , Resolução de Problemas/fisiologia , Pensamento/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Análise e Desempenho de Tarefas
10.
Nanoscale Adv ; 4(10): 2294-2302, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35706845

RESUMO

We propose a route for the rational design of engineered graphene-based nanostructures, which feature enormously enhanced electric fields in their proximity. Geometrical arrangements are inspired by nanopatterns allowing single molecule detection on noble metal substrates, and are conceived to take into account experimental feasibility and ease in fabrication processes. The attention is especially focused on enhancement effects occurring close to edge defects and grain boundaries, which are usually present in graphene samples. There, very localized hot-spots are created, with enhancement factors comparable to noble metal substrates, thus potentially paving the way for single molecule detection from graphene-based substrates.

11.
ACS Photonics ; 9(9): 3025-3034, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36164484

RESUMO

Optical properties of metal nanostructures are the basis of several scientific and technological applications. When the nanostructure characteristic size is of the order of few nm or less, it is generally accepted that only a description that explicitly describes electrons by quantum mechanics can reproduce faithfully its optical response. For example, the plasmon resonance shift upon shrinking the nanostructure size (red-shift for simple metals, blue-shift for d-metals such as gold and silver) is universally accepted to originate from the quantum nature of the system. Here we show instead that an atomistic approach based on classical physics, ωFQFµ (frequency dependent fluctuating charges and fluctuating dipoles), is able to reproduce all the typical "quantum" size effects, such as the sign and the magnitude of the plasmon shift, the progressive loss of the plasmon resonance for gold, the atomistically detailed features in the induced electron density, and the non local effects in the nanoparticle response. To support our findings, we compare the ωFQFµ results for Ag and Au with literature time-dependent DFT simulations, showing the capability of fully classical physics to reproduce these TDDFT results. Only electron tunneling between nanostructures emerges as a genuine quantum mechanical effect, that we had to include in the model by an ad hoc term.

12.
Minerva Surg ; 77(3): 257-262, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34338455

RESUMO

BACKGROUND: Pudendal nerve block (PNB) is commonly used in pudendal neuralgia (PN) and, as anesthesiological technique, in obstetrical and urological procedures. The purpose of this retrospective study was to compare the efficacy of PNB with other anesthesiolocal techniques in proctological surgery. METHODS: A total of 362 patients were seen from a 22-month-time interval. Surgical indication was placed after a conservative therapy. Seventy-eight patients underwent surgery: 42 with spinal anesthesia with PNB and 36 with PNB alone according to their anatomical characteristics. All the patients underwent PNB in lithotomy position and with a perirectal approach. The success rate of PNB was evaluated in postoperative pain control with the VAS score, after the first and the second evacuation. The follow-up also included a third check on the seventh day after surgery. RESULTS: In postoperative period, the mean VAS score found after the first evacuation in patients undergoing PNB was 2.66, after the second evacuation was 1.55, while the VAS score on the seventh day was 0.38. The mean VAS score in the group who underwent spinal anesthesia and PNB were respectively 3.71 and 1.80 after the first and second evacuation. The VAS score calculated on the seventh day was 0.50. There were no statistically significant differences in the VAS score between the 2 groups (P>0.05). CONCLUSIONS: PNB may be a valid alternative to spinal anesthesia in proctological patients. PNB has proven to be both safe and effective technique.


Assuntos
Bloqueio Nervoso , Nervo Pudendo , Neuralgia do Pudendo , Humanos , Bloqueio Nervoso/métodos , Dor Pós-Operatória/prevenção & controle , Nervo Pudendo/cirurgia , Neuralgia do Pudendo/cirurgia , Estudos Retrospectivos
13.
Psychol Sci ; 22(5): 674-81, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21474840

RESUMO

To mentally extrapolate the trajectory of a moving object that disappears from sight, different sources of information can be exploited: memory of its last visible position, its inferred movement through time, and general understanding of the causal structure of the scene. It is often assumed that these cues are integrated into unified analog mental representations. In our experiment, participants predicted the position of an object that disappeared behind an occluder and estimated the degree to which the movement was caused by another object. They made considerable errors in predicting imagined displacements. Moreover, their predictions were misaligned with their judgments of causality. They predicted the positions of the invisible moving objects better in events that they judged less causally correct than in events that they judged more causally correct. These results suggest that physical and cognitive parameters of imagined dynamic events do not merge into unitary mental models simulating actual states of the world.


Assuntos
Imaginação/fisiologia , Julgamento/fisiologia , Percepção de Movimento/fisiologia , Adulto , Análise de Variância , Sinais (Psicologia) , Humanos , Memória/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem
14.
J Surg Case Rep ; 2021(10): rjab451, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34733470

RESUMO

Malrotation of the gut is a rare occurrence, commonly diagnosed during childhood, but occasionally diagnosed in adults. In children, intestinal obstruction is the most common manifestation, whereas in adult patients, the diagnosis is more challenging since the symptoms are less specific with several episodes of abdominal pain and vomit. In a particular epidemic period, like the one we are going through, these generic symptoms may mislead to a wrong diagnosis. We present the case of a young man in which occlusion due to intestinal malrotation has been misinterpreted as gastroenteric symptoms of severe acute respiratory syndrome coronavirus 2 infection, and we also overview the correct Ladd's technique, commonly performed by pediatrical surgeon, but unusual operation for adult general surgeons.

15.
Proc Natl Acad Sci U S A ; 104(48): 19156-9, 2007 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-18025482

RESUMO

Rational agents should integrate probabilities in their predictions about uncertain future events. However, whether humans can do this, and if so, how this ability originates, are controversial issues. Here, we show that 12-month-olds have rational expectations about the future based on estimations of event possibilities, without the need of sampling past experiences. We also show that such natural expectations influence preschoolers' reaction times, while frequencies modify motor responses, but not overt judgments, only after 4 years of age. Our results suggest that at the onset of human decision processes the mind contains an intuition of elementary probability that cannot be reduced to the encountered frequency of events or elementary heuristics.


Assuntos
Tomada de Decisões/fisiologia , Previsões , Intuição/fisiologia , Julgamento/fisiologia , Probabilidade , Resolução de Problemas/fisiologia , Psicologia da Criança , Fatores Etários , Pré-Escolar , Cognição , Feminino , Fixação Ocular , Humanos , Lactente , Masculino , Desempenho Psicomotor , Tempo de Reação , Método Simples-Cego
16.
J Phys Chem Lett ; 11(18): 7595-7602, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32805117

RESUMO

We demonstrate that the plasmonic properties of realistic graphene and graphene-based materials can effectively and accurately be modeled by a novel, fully atomistic, yet classical, approach, named ωFQ. Such a model is able to reproduce all plasmonic features of these materials and their dependence on shape, dimension, and fundamental physical parameters (Fermi energy, relaxation time, and two-dimensional electron density). Remarkably, ωFQ is able to accurately reproduce experimental data for realistic structures of hundreds of nanometers (∼370k atoms), which cannot be afforded by any ab initio method. Also, the atomistic nature of ωFQ permits the investigation of complex shapes, which can hardly be dealt with by exploiting widespread continuum approaches.

17.
Front Chem ; 8: 340, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32457870

RESUMO

The fully atomistic model, ωFQ, based on textbook concepts (Drude theory, electrostatics, quantum tunneling) and recently developed by some of the present authors in Nanoscale, 11, 6004-6015 is applied to the calculation of the optical properties of complex Na, Ag, and Au nanostructures. In ωFQ, each atom of the nanostructures is endowed with an electric charge that can vary according to the external electric field. The electric conductivity between nearest atoms is modeled by adopting the Drude model, which is reformulated in terms of electric charges. Quantum tunneling effects are considered by letting the dielectric response of the system arise from atom-atom conductivity. ωFQ is challenged to reproduce the optical response of metal nanoparticles of different sizes and shapes, and its performance is compared with continuum Boundary Element Method (BEM) calculations.

18.
J Surg Case Rep ; 2020(9): rjaa344, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33005322

RESUMO

Mucinous lesions of appendix are a rare clinical entity and may be neoplastic or non-neoplastic. The diagnosis is usual incidental during computed tomography scan or colonoscopy performed for general abdominal symptoms or occasional finding during operation for acute appendicitis. For this reason, initial treatment should be tailored to the situation, aiming at complete resection of the appendix with disease-free margins: this can be achieved by simple appendectomy or more extensive resection. The pathological examination of the specimen is the key to offer the patient a correct and complete treatment, and, if a neoplastic pathology is found, the case should be discussed in multidisciplinary group. We describe three cases with different clinical presentation leading to different surgical treatment: one elective case, in which the diagnosis was suspected preoperatively; and two urgent cases, one mimicking an intussusception and another one presenting as an acute appendicitis.

19.
Neuropsychologia ; 47(4): 1107-16, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19166867

RESUMO

Elementary deduction is the ability of unreflectively drawing conclusions from explicit or implicit premises, on the basis of their logical forms. This ability is involved in many aspects of human cognition and interactions. To date, limited evidence exists on its cortical bases. We propose a model of elementary deduction in which logical inferences, memory, and meta-logical control are separable subcomponents. We explore deficits in patients with left, medial and right frontal lesions, by both studying patients' deductive abilities and providing measures of their meta-logical sensitivity for proof difficulty. We show that lesions to left lateral and medial frontal cortex impair abilities at solving elementary deductive problems, but not so lesions to right frontal cortex. Furthermore, we show that memory deficits differentially affect patients according to the locus of the lesion. Left lateral patients with working memory deficits had defective deductive abilities, but not so left lateral patients with spared working memory. In contrast, in medial patients both deductive and meta-deductive abilities were affected regardless of the presence of memory deficits. Overall, the results are compatible with a componential view of elementary deduction, and call for the elaboration of more fine-grained models of deductive abilities.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiopatologia , Compreensão/fisiologia , Memória/fisiologia , Resolução de Problemas/fisiologia , Adulto , Análise de Variância , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Córtex Cerebral/patologia , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia Computadorizada por Raios X/métodos , Comportamento Verbal/fisiologia
20.
Science ; 359(6381): 1263-1266, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29590076

RESUMO

Infants are able to entertain hypotheses about complex events and to modify them rationally when faced with inconsistent evidence. These capacities suggest that infants can use elementary logical representations to frame and prune hypotheses. By presenting scenes containing ambiguities about the identity of an object, here we show that 12- and 19-month-old infants look longer at outcomes that are inconsistent with a logical inference necessary to resolve such ambiguities. At the moment of a potential deduction, infants' pupils dilated, and their eyes moved toward the ambiguous object when inferences could be computed, in contrast to transparent scenes not requiring inferences to identify the object. These oculomotor markers resembled those of adults inspecting similar scenes, suggesting that intuitive and stable logical structures involved in the interpretation of dynamic scenes may be part of the fabric of the human mind.


Assuntos
Desenvolvimento Infantil , Formação de Conceito/fisiologia , Resolução de Problemas/fisiologia , Movimentos Oculares , Humanos , Lactente
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