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1.
Cogn Neuropsychol ; 40(3-4): 167-185, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38006205

RESUMO

Feature generation tasks and feature databases are important for understanding how knowledge is organized in semantic memory, as they reflect not only the kinds of information that individuals hold about objects but also how objects are conceptually represented. Traditionally, semantic norms focus on a variety of object categories and, as a result, have a small number of concepts per semantic category. Here, our main goal is to create a more fine-grained feature database exclusively for one category of objects-manipulable objects. This database contributes to the understanding of within-category, content-specific processing. To achieve this, we asked 130 participants to freely generate features for 80 manipulable objects and another group of 32 participants to generate action features for the same objects. We then compared our databases with other published semantic norms and found high similarity between them. In our databases, we calculated the similarity between objects in terms of visual, functional, encyclopaedic, and action feature types using Spearman correlation, Baker's gamma index, and cophenetic correlation. We discovered that objects were grouped in a distinctive and meaningful way according to feature type. Finally, we tested the validity of our databases by asking three groups of participants to perform a feature verification experiment while manipulating production frequency. Our results demonstrate that participants can recognize and associate the features of our databases with specific manipulable objects. Participants were faster to verify high-frequency features than low-frequency features. Overall, our data provide important insights into how we process manipulable objects and can be used to further inform cognitive and neural theories of object processing and identification.


Assuntos
Memória , Semântica , Humanos
2.
Commun Biol ; 6(1): 940, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37709924

RESUMO

Understanding how we recognize objects requires unravelling the variables that govern the way we think about objects and the neural organization of object representations. A tenable hypothesis is that the organization of object knowledge follows key object-related dimensions. Here, we explored, behaviorally and neurally, the multidimensionality of object processing. We focused on within-domain object information as a proxy for the decisions we typically engage in our daily lives - e.g., identifying a hammer in the context of other tools. We extracted object-related dimensions from subjective human judgments on a set of manipulable objects. We show that the extracted dimensions are cognitively interpretable and relevant - i.e., participants are able to consistently label them, and these dimensions can guide object categorization; and are important for the neural organization of knowledge - i.e., they predict neural signals elicited by manipulable objects. This shows that multidimensionality is a hallmark of the organization of manipulable object knowledge.


Assuntos
Percepção Espacial , Humanos
3.
Geroscience ; 45(4): 2267-2287, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36749471

RESUMO

Episodic memory decline is a major signature of both normal and pathological aging. Many neural regions have been implicated in the processes subserving both episodic memory and typical aging decline. Here, we demonstrate that the cerebellum is causally involved episodic memory under aging. We show that a 12-day neurostimulation program delivered to the right cerebellum led to improvements in episodic memory performance under healthy aging that long outlast the stimulation period - healthy elderly individuals show episodic memory improvement both immediately after the intervention program and in a 4-month follow-up. These results demonstrate the causal relevance of the cerebellum in processes associated with long-term episodic memory, potentially highlighting its role in regulating and maintaining cognitive processing. Moreover, they point to the importance of non-pharmacological interventions that prevent or diminish cognitive decline in healthy aging.


Assuntos
Disfunção Cognitiva , Memória Episódica , Humanos , Idoso , Envelhecimento/fisiologia , Cognição , Cerebelo
4.
Appl Neuropsychol Adult ; 30(2): 169-175, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-33984245

RESUMO

The Toulouse-Piéron Cancelation Test (TP) is a classic psychometric tool for the assessment of selective/sustained attention, processing speed and visuo-perceptual abilities. It is commonly used in neurological disorders such as epilepsy, multiple sclerosis or Alzheimer's disease. It encompasses two main indexes: Work-Efficiency (WE) and Dispersion-Index (DI). The aim of this study is to provide normative scores for the TP in a sample of Portuguese healthy adults. The TP was administered to a convenience sample of 357 cognitively-dwelling subjects aged between [45 and 86] years old, following a standard assessment protocol. The normative scores were adjusted for age and education. Education was the main predictor of TP-WE (R2 = .310), whereas the influence of age on this score was lower (R2 = .191). These two variables explained 50.1% of the variance of the results. Regarding TP-DI, education was also the main predictor of the results (R2 = .039), whereas age was responsible for R2 = .011 and together, they explained 5% of the variance of TP-DI. TP performances are strongly influenced by age and education. This is the first study focused on the establishment of normative data after the age of 45 in the Portuguese population, allowing a reliable assessment in both clinical and research contexts.


Assuntos
Doença de Alzheimer , Adulto , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Testes Neuropsicológicos , Portugal , Psicometria , Escolaridade , Valores de Referência
5.
Cortex ; 157: 142-154, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36283136

RESUMO

Neural processing within a local brain region that responds to more than one object category (e.g., hands and tools) nonetheless have different functional connectivity patterns with other distal brain areas, which suggests that local processing can affect and/or be affected by processing in distal areas, in a category-specific way. Here we wanted to test whether administering either a hand- or tool-related training task in tandem with transcranial direct current stimulation (tDCS) to a region that responds both to hands and tools (posterior middle temporal gyrus; pMTG), modulated local and distal neural processing more for the trained than the untrained category in a subsequent fMRI task. After each combined tDCS/training session, participants viewed images of tools, hands, and animals, in an fMRI scanner. Using multivoxel pattern analysis, we found that tDCS stimulation to pMTG indeed improved the classification accuracy between tools vs. animals, but only when combined with a tool and not a hand training task. Surprisingly, tDCS stimulation to pMTG also improved classification accuracy between hands vs. animals when combined with a tool but not a hand training task. Our findings suggest that overlapping but functionally-specific networks may be engaged separately by using a category-specific training task together with tDCS - a strategy that can be applied more broadly to other cognitive domains using tDCS. By hypothesis, these effects on local processing are a direct result of within-domain connectivity constraints from domain-specific networks that are at play in the processing and organization of object representations.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Estimulação Transcraniana por Corrente Contínua/métodos , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Imageamento por Ressonância Magnética/métodos , Mãos , Encéfalo/diagnóstico por imagem
6.
Neurol Sci ; 43(6): 3717-3728, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35028780

RESUMO

In Portugal, there is no gold standard test to assess acute stroke patients in the hospital context. However, cognitive deficits are common after a stroke episode and are followed by a negative impact on a patient's quality of life and rehabilitation. Here, we first aimed to adapt the Oxford Cognitive Screening to European Portuguese speakers (OCS-Pt), develop normative data cut-offs, and report the psychometric properties of the OCS-Pt. The second aim was to test the incidence of impairments in acute stroke patients. We tested 137 healthy participants aged between 25 and 92 years old, and we report normative cut-offs based on the 5th and 95th percentile, and on the patterns for age and education level. Our results are similar to other European OCS versions, and results using convergent and divergent validity show satisfactory values ranged between moderate to high. Additionally, 146 acute stroke patients, in the first week after the stroke episode, performed the OCS-Pt. Results show that this is an inclusive test and allows to discriminate between impaired and preserved functions. In conclusion, OCS-Pt is a promising cognitive screening tool to assess acute stroke survivors to be used in stroke care in Portugal.


Assuntos
Qualidade de Vida , Acidente Vascular Cerebral , Adulto , Idoso , Idoso de 80 Anos ou mais , Cognição , Humanos , Pessoa de Meia-Idade , Portugal/epidemiologia , Psicometria , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/psicologia
7.
Exp Brain Res ; 240(1): 221-235, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34694466

RESUMO

Transcranial direct current stimulation (tDCS) has been studied to enhance extinction-based treatments for anxiety disorders. However, the field shows conflicting results about its anxiolytic effect and only a few studies have observed the extinction of consolidated memories. We looked to study the effect of offline 1 mA tDCS over the right dorsolateral pre-frontal cortex across the fear pathways, in consolidated fear response during delayed extinction. Participants (N = 34 women) underwent in a two-day fear conditioning procedure. On day 1, participants were assigned to the control group (N = 18) or the tDCS group (N = 16) and went through a fear acquisition procedure. On day 2, the tDCS group received 20 min tDCS before extinction and while inside the MRI scanner. The control group completed the extinction procedure only. The tDCS session (for the tDCS group) and the fMRI scan (for both groups) were completed just on the second day. Univariate fMRI analysis showed stimulation-dependent activity during late extinction with the tDCS group showing decreased neural activity during the processing of threat cues (CS +) and increased activity during the processing of safety cues (CS -), in prefrontal, postcentral and paracentral regions, during late extinction. ROI to whole-brain psychophysiological interaction (PPI) analysis showed the tDCS effect on the connectivity between the left dorsolateral prefrontal cortex three cortical-amygdalo-hippocampal-cerebellar pathway clusters during the processing of the CS + in late extinction (TFCE corrected; p < 0.05). Increased neuronal activity during the processing of safety cues and stronger coupling during the processing of threat cues might be the mechanisms by which tDCS contributes to stimuli discrimination.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Cerebelo , Extinção Psicológica , Medo , Feminino , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal
8.
Cortex ; 141: 449-464, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34147827

RESUMO

Deciding how to manipulate an object to fulfill a goal requires accessing different types of object-related information. How these different types of information are integrated and represented in the brain is still an open question. Here, we focus on examining two types of object-related information-tool-gesture knowledge (i.e., how to manipulate an object), and tool-gesture production (i.e., the actual manipulation of an object). We show a double dissociation between tool-gesture knowledge and tool-gesture production: Patient FP presents problems in pantomiming tool use in the context of a spared ability to perform judgments about an object's manipulation, whereas Patient LS can pantomime tool use, but is impaired at performing manipulation judgments. Moreover, we compared the location of the lesions in FP and LS with those sustained by two classic ideomotor apraxic patients (IMA), using a cortical thickness approach. Patient FP presented lesions in common with our classic IMA that included the left inferior parietal lobule (IPL), and specifically the supramarginal gyrus, the left parietal operculum, the left premotor cortex and the left inferior frontal gyrus, whereas Patient LS and our classic IMA patients presented common lesions in regions of the superior parietal lobule (SPL), motor areas (as primary somatosensory cortex, premotor cortex and primary motor cortex), and frontal areas. Our results show that tool-gesture production and tool-gesture knowledge can be behaviorally and neurally doubly dissociated and put strong constraints on extant theories of action and object recognition and use.


Assuntos
Apraxias , Gestos , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Lobo Parietal
9.
Cortex ; 139: 152-165, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33873036

RESUMO

When we see a manipulable object (henceforth tool) or a hand performing a grasping movement, our brain is automatically tuned to how that tool can be grasped (i.e., its affordance) or what kind of grasp that hand is performing (e.g., a power or precision grasp). However, it remains unclear where visual information related to tools or hands are transformed into abstract grasp representations. We therefore investigated where different levels of abstractness in grasp information are processed: grasp information that is invariant to the kind of stimuli that elicits it (tool-hand invariance); and grasp information that is hand-specific but viewpoint-invariant (viewpoint invariance). We focused on brain areas activated when viewing both tools and hands, i.e., the posterior parietal cortices (PPC), ventral premotor cortices (PMv), and lateral occipitotemporal cortex/posterior middle temporal cortex (LOTC/pMTG). To test for invariant grasp representations, we presented participants with tool images and grasp videos (from first or third person perspective; 1pp or 3pp) inside an MRI scanner, and cross-decoded power versus precision grasps across (i) grasp perspectives (viewpoint invariance), (ii) tool images and grasp 1pp videos (tool-hand 1pp invariance), and (iii) tool images and grasp 3pp videos (tool-hand 3pp invariance). Tool-hand 1pp, but not tool-hand 3pp, invariant grasp information was found in left PPC, whereas viewpoint-invariant information was found bilaterally in PPC, left PMv, and left LOTC/pMTG. These findings suggest different levels of abstractness-where visual information is transformed into stimuli-invariant grasp representations/tool affordances in left PPC, and viewpoint invariant but hand-specific grasp representations in the hand network.


Assuntos
Mapeamento Encefálico , Mãos , Força da Mão , Humanos , Imageamento por Ressonância Magnética , Lobo Parietal , Desempenho Psicomotor
10.
E-Cienc. inf ; 10(2)dic. 2020.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1384731

RESUMO

Resumen: Elegir una carrera universitaria es una decisión compleja que impacta el desarrollo profesional, personal y el futuro de todo individuo. Como apoyo a este proceso, las universidades ayudan a estudiantes que están terminando la secundaria y que se encuentran en una transición hacia la educación superior, mediante la organización de ferias vocacionales; por lo anterior, el presente artículo narra la experiencia de divulgación de las carreras ofrecidas por la Escuela de Bibliotecología y Ciencias de la Información (EBCI) de la Universidad de Costa Rica (UCR) en el marco de la Feria Vocacional 2019, donde se explica cómo se diseñaron e implementaron las estrategias de divulgación a través de la creación de diferentes actividades experienciales sobre labores cotidianas de la persona profesional en Bibliotecología, la generación de material gráfico y audiovisual sobre la carrera y la confección de recursos para apoyar el discurso expuesto. Así mismo, se evalúan las estrategias y los recursos utilizados tanto con el personal colaborador como con la comunidad estudiantil que visitó el evento. Se concluye que las actividades experienciales son recibidas por los participantes con mayor anuencia y que les permite tener una visión más real de la carrera, además, se recomienda utilizar este tipo de recursos para futuras ferias vocacionales.


Abstract: Choosing a university career is a complex decision that impacts the professional, personal and future development of every individual. To support this process, universities offer grants to students who are finishing their secondary studies and who are in a transition to higher education, by organizing vocational fairs. This article narrates the experience of dissemination of the careers offered by the School of Library and Information Sciences of the University of Costa Rica within the framework of the 2019 Vocational Fair. It explains how the dissemination strategies were designed and implemented by creating of different experiential activities on the daily tasks of the professional person in library science, the generation of graphic and audiovisual material on the career and the preparation of resources to support the exposed discourse. Likewise, the strategies and resources used are evaluated both with the collaborating staff and with the student community that visited the event. Finally, it is concluded that the experiential activities are received by the participants with greater consent and that it allows them to have a more real vision of the career, in addition, it is recommended to use this type of resources for future vocational fairs.


Assuntos
Orientação Vocacional , Faculdades de Biblioteconomia/tendências , Costa Rica , Materiais Educativos e de Divulgação , Tecnologia da Informação
11.
Curr Biol ; 30(20): 4071-4077.e4, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-32795446

RESUMO

The spatial coordinate system in which a stimulus representation is embedded is known as its reference frame. Every visual representation has a reference frame [1], and the visual system uses a variety of reference frames to efficiently code visual information [e.g., 1-5]. The representation of faces in early stages of visual processing depends on retino-centered reference frames, but little is known about the reference frames that code the high-level representations used to make judgements about faces. Here, we focus on a rare and striking disorder of face perception-hemi-prosopometamorphopsia (hemi-PMO)-to investigate these reference frames. After a left splenium lesion, Patient A.D. perceives features on the right side of faces as if they had melted. The same features were distorted when faces were presented in either visual field, at different in-depth rotations, and at different picture-plane orientations including upside-down. A.D.'s results indicate faces are aligned to a view- and orientation-independent face template encoded in a face-centered reference frame, that these face-centered representations are present in both the left and right hemisphere, and that the representations of the left and right halves of a face are dissociable.


Assuntos
Dano Encefálico Crônico/patologia , Reconhecimento Facial/fisiologia , Lateralidade Funcional/fisiologia , Distorção da Percepção/fisiologia , Percepção Visual/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Orientação Espacial , Campos Visuais
12.
E-Cienc. inf ; 9(1): 60-83, ene.-jun. 2019. tab, graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1089857

RESUMO

Resumen El artículo expone cómo se desarrolló un proceso de arquitectura de información para el sitio Web del Centro Centroamericano de Población (CCP) de la Universidad de Costa Rica (UCR), como parte de un estudio dentro del campo de la Bibliotecología. Explica, ampliamente, cómo se realizó el análisis del sitio, la identificación de los requerimientos, la estructura y los sistemas de etiquetado y navegación requeridos por el CCP para mejorar su sitio Web. Durante este proceso se diseñaron, también, todas las visualizaciones (wireframes) de las páginas que conforman la versión de escritorio de este sitio, además, se elaboraron visualizaciones para la versión responsive requerida por los dispositivos móviles. Se concluye que la arquitectura de información es un proceso que demanda de planificación y análisis del problema a tratar, al mismo tiempo, es un campo laboral importante para profesionales en Bibliotecología con interés en incorporar la tecnología a su práctica profesional.


Abstract The development of an information architecture process on the website of the Central American Center for Population from the University of Costa Rica is explained. This investigation is in the field of library and information sciences and explains how the website was analyzed, how the requirements were lifted, how the structure and the labeling and navigation systems were developed in order to improve the website. During this process, all the wireframes for the desktop version of the website were designed, also, wireframes for the responsive version were created. It concludes that information architecture is a process that requires a lot of planning and analysis of the problem, also, it is an important working area for librarians that are interested in getting involved with technology.


Assuntos
Redes de Comunicação de Computadores/organização & administração , Demografia , Gestão da Informação , Internet , Design Centrado no Usuário , Costa Rica , Academias e Institutos , Acesso à Internet , Gerenciamento de Dados
13.
J Alzheimers Dis ; 61(3): 1097-1105, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29254094

RESUMO

BACKGROUND: Several demographic and genetic prognostic factors of conversion from mild cognitive impairment (MCI) to Alzheimer's disease (AD) have been recognized so far. The most frequent polymorphism of butyrylcholinesterase (BuChE), the K-variant, has been proposed as a risk factor for AD, but data regarding its influence on early disease progression is still limited. OBJECTIVE: To investigate the influence of the BuChE-K variant in MCI progression to AD. METHODS: 96 MCI patients were included in the study and were genotyped for BuChE-K variant and Apolipoprotein E (ApoE). Cerebrospinal fluid (CSF) BuChE activity, as well as the levels of AD biomarkers amyloid-ß 42 (Aß42), total and hyperphosphorylated tau (t-tau and p-tau) were also determined. RESULTS: No significant differences were found in either BuChE-K variant or BuChE activity between MCI patients that progressed to AD (MCI-AD) and patients that remained stable during clinical follow-up (MCI-St). As expected, baseline CSF levels of Aß42 were significantly lower and t-Tau, p-Tau, and ApoE ɛ4 allele frequency were significantly higher in MCI-AD patients. An association between the ApoE ɛ4 allele and the BuChE-K variant in MCI-AD, but not in MCI-St patients, was found with patients carrying both alleles presenting the highest incidence of progression and the lowest estimated time of progression to AD. CONCLUSION: Although BuChE-K alone does not seem to play a major role in progression to AD in MCI patients, a synergistic effect with the ApoE ɛ4 allele was found, highlighting the importance of assessing these combined genotypes for evaluating risk progression in MCI patients.


Assuntos
Doença de Alzheimer/genética , Biomarcadores/líquido cefalorraquidiano , Butirilcolinesterase/genética , Disfunção Cognitiva/genética , Progressão da Doença , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Apolipoproteínas E/genética , Butirilcolinesterase/líquido cefalorraquidiano , Disfunção Cognitiva/líquido cefalorraquidiano , Feminino , Predisposição Genética para Doença , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Proteínas tau/líquido cefalorraquidiano
14.
Rev. odonto ciênc ; 21(52): 105-111, abr.-jun. 2006. tab
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-457138

RESUMO

O objetivo do presente estudo foi testar o conhecimento sobre uso racional de flúor adquirido através de grupo de discussão (GD). Um grupo de 47 pais de crianças pré-escolares constituiu a amostra após a assinatura de um termo de consentimento livre e esclarecido. Este estudo foi aprovado por um Comitê de ética em Pesquisa. Para averiguação do nível de conhecimento inicial sobre o tema proposto, os participantes responderam a um questionário com 14 perguntas abertas e fechadas. Seis meses após esta etapa, foi realizado um GD sobre o uso racional de flúor. O GD proposto abordou a metodologia pedagógica problematizadora e contou com a participação ativa dos pais e de três cirurgiões dentistas. Neste momento foram apresentadas afirmações sobre a utilização do flúor pela população, a partir das quais a discussão era deflagrada. Alguns dias após, os pais responderam novamente o questionário inicial. Os dados foram submetidos aos testes estatístico Qui-quadrado e exato de Fisher através do programa SPSS. Houve diferença estatisticamente significante entre praticamente todas as respostas no primeiro e segundo questionários (p < 0,005), sendo que no segundo, houve um maior número de respostas corretas. A técnica educativa avaliada mostrou-se efetiva na incorporação de novos conhecimentos sobre o uso racional de flúor pelos pais, evidenciando a eficácia da metodologia empregada.


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Educação em Odontologia , Fluoretos , Fluorose Dentária , Promoção da Saúde , Inquéritos e Questionários
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