324 research outputs found
Neural representations underlying mental imagery as unveiled by representation similarity analysis
It is commonly acknowledged that visual imagery and perception rely on the same content-dependent brain areas in the high-level visual cortex (HVC). However, the way in which our brain processes and organizes previous acquired knowledge to allow the generation of mental images is still a matter of debate. Here, we performed a representation similarity analysis of three previous fMRI experiments conducted in our laboratory to characterize the neural representation underlying imagery and perception of objects, buildings and faces and to disclose possible dissimilarities in the neural structure of such representations. To this aim, we built representational dissimilarity matrices (RDMs) by computing multivariate distances between the activity patterns associated with each pair of stimuli in the content-dependent areas of the HVC and HC. We found that spatial information is widely coded in the HVC during perception (i.e. RSC, PPA and OPA) and imagery (OPA and PPA). Also, visual information seems to be coded in both preferred and non-preferred regions of the HVC, supporting a distributed view of encoding. Overall, the present results shed light upon the spatial coding of imagined and perceived exemplars in the HVC
One's own country and familiar places in the mind's eye:different topological representations for navigational and non-navigational contents
Visual mental imagery is a process that draws on different cognitive abilities and is affected by the contents of mental images. Several studies have demonstrated that different brain areas subtend the mental imagery of navigational and non-navigational contents. Here, we set out to determine whether there are distinct representations for navigational and geographical images. Specifically, we used a Spatial Compatibility Task (SCT) to assess the mental representation of a familiar navigational space (the campus), a familiar geographical space (the map of Italy) and familiar objects (the clock). Twenty-one participants judged whether the vertical or the horizontal arrangement of items was correct. We found that distinct representational strategies were preferred to solve different categories on the SCT, namely, the horizontal perspective for the campus and the vertical perspective for the clock and the map of Italy. Furthermore, we found significant effects due to individual differences in the vividness of mental images and in preferences for verbal versus visual strategies, which selectively affect the contents of mental images. Our results suggest that imagining a familiar navigational space is somewhat different from imagining a familiar geographical space
The effects of financialisation and financial development on investment: Evidence from firm-level data in Europe
In this paper we estimate the effects of financialization on physical investment in selected western European countries using panel data based on the balance-sheets of publicly listed non-financial companies (NFCs) supplied by Worldscope for the period 1995-2015. We find robust evidence of an adverse effect of both financial payments
(interests and dividends) and financial incomes on investment in fixed assets by the NFCs. This finding is robust for both the pool of all Western European firms and single country estimations. The negative impacts of financial incomes are non-linear with respect to the companies’ size: financial incomes crowd-out investment in large companies, and have a positive effect on the investment of only small, relatively more credit-constrained companies. Moreover, we find that a higher degree of financial development is associated with a stronger negative effect of financial incomes on companies’ investment. This finding challenges the common wisdom on ‘finance-growth nexus’. Our findings support the ‘financialization thesis’ that the increasing orientation of the non-financial sector towards financial activities is ultimately leading to lower physical investment, hence to stagnant or fragile growth, as well as long term stagnation in productivity
Desempenho de uma população brasileira no teste de alfabetização funcional para adultos na área de saúde
OBJECTIVE: To analyze the scoring obtained by an instrument, which evaluates the ability to read and understand items in the health care setting, according to education and age. METHODS: The short version of the Test of Functional Health Literacy in Adults was administered to 312 healthy participants of different ages and years of schooling. The study was conducted between 2006 and 2007, in the city of São Paulo, Southeastern Brazil. The test includes actual materials such as pill bottles and appointment slips and measures reading comprehension, assessing the ability to read and correctly pronounce a list of words and understand both prose passages and numerical information. Pearson partial correlations and a multiple regression model were used to verify the association between its scores and education and age. RESULTS: The mean age of the sample was 47.3 years(sd=16.8) and the mean education was 9.7 years(sd=5; range: 1 - 17). A total of 32.4% of the sample showed literacy/numeracy deficits, scoring in the inadequate and marginal functional health literacy ranges. Among the elderly (65 years or older) this rate increased to 51.6%. There was a positive correlation between schooling and scores (r=0.74; pOBJETIVO: Analizar los escores de instrumento que evalúa habilidad de lectura y comprensión de materiales del área de salud según escolaridad y edad. MÉTODOS: Fueron evaluados 312 participantes saludables de diferentes edades por medio de la versión reducida del instrumento Test of Functional Health Literacy in Adults. El estudio fue realizado entre 2006 y 2007 en la ciudad de Sao Paulo (Sureste de Brasil). El instrumento incluye materiales como frascos de medicamentos y cartones de para marcar consultas, evaluando la comprensión de lectura y de conceptos numéricos. Las pruebas de correlación parcial y de Pearson y un modelo de regresión múltiple fueron usados para verificar la asociación entre los escores en el instrumento, escolaridad y edad. RESULTADOS: Los promedios de edad y de escolaridad de la muestra fueron respectivamente 47,3 (dp=16,8) y 9,7 (dp=5; de uno a 17 años de estudio). El total de 32,4% de la muestra mostraron déficit de alfabetización funcional/uso de conceptos numéricos en el área de salud, con desempeño inadecuado o limÃtrofe en el instrumento. Entre ancianos (65 años o más) esta tasa afectó 51,6%. Se encontró correlación positiva entre años de estudio y escores en el instrumento (r=0,740; p< 0,01) y correlación negativa entre edad y escores en el instrumento (r=-0,259; p< 0,01).La correlación entre escores en el instrumento y edad no fue significativa cuando los efectos de la escolaridad fueron controlados (r=-0,031, p=0,584). Una asociación significativa (B=3,877, Beta=0,733; p< 0,001) fue encontrada entre años de estudio y escores en el instrumento. La edad no fue una variable predictiva en el modelo (B=-0,035, Beta=-0,22; p=0,584). CONCLUSIONES: El instrumento es adecuado para evaluar la alfabetización funcional en salud en la población brasilera. El elevado número de individuos clasificados como analfabetos funcionales indica la importancia de adopción de medidas especiales para ayudar estos individuos a comprender correctamente las orientaciones para cuidados de salud.OBJETIVO: Analisar os escores de instrumento que avalia habilidade de leitura e compreensão de materiais da área da saúde segundo escolaridade e idade. MÉTODOS: Foram avaliados 312 participantes saudáveis de diferentes idades por meio da versão reduzida do instrumento Test of Functional Health Literacy in Adults. O estudo foi realizado entre 2006 e 2007 na cidade de São Paulo (SP). O instrumento envolve materiais como frascos de medicamentos e cartões de agendamento de consultas, avaliando a compreensão de leitura e de conceitos numéricos. Os testes de correlação parcial e de Pearson e um modelo de regressão múltipla foram usados para verificar a associação entre os escores no instrumento, escolaridade e idade. RESULTADOS: As médias de idade e de escolaridade da amostra foram respectivamente 47,3 (dp=16,8 ) e 9,7 (dp=5; de um a 17 anos de estudo). O total de 32,4% da amostra mostraram déficits de alfabetização funcional/ uso de conceitos numéricos na área de saúde, com desempenho inadequado ou limÃtrofe no instrumento. Entre idosos (65 anos ou mais) esta taxa atingiu 51,6%. Encontrou-se correlação positiva entre anos de estudo e escores no instrumento (r=0,740;
Know Thyself: Behavioral Evidence for a Structural Representation of the Human Body
Background: Representing one's own body is often viewed as a basic form of self-awareness. However, little is known about structural representations of the body in the brain.Methods and Findings: We developed an inter-manual version of the classical "in-between'' finger gnosis task: participants judged whether the number of untouched fingers between two touched fingers was the same on both hands, or different. We thereby dissociated structural knowledge about fingers, specifying their order and relative position within a hand, from tactile sensory codes. Judgments following stimulation on homologous fingers were consistently more accurate than trials with no or partial homology. Further experiments showed that structural representations are more enduring than purely sensory codes, are used even when number of fingers is irrelevant to the task, and moreover involve an allocentric representation of finger order, independent of hand posture.Conclusions: Our results suggest the existence of an allocentric representation of body structure at higher stages of the somatosensory processing pathway, in addition to primary sensory representation
Does spatial locative comprehension predict landmark-based navigation?
In the present study we investigated the role of spatial locative comprehension in learning and retrieving pathways when landmarks were available and when they were absent in a sample of typically developing 6- to 11-year-old children. Our results show that the more proficient children are in understanding spatial locatives the more they are able to learn pathways, retrieve them after a delay and represent them on a map when landmarks are present in the environment. These findings suggest that spatial language is crucial when individuals rely on sequences of landmarks to drive their navigation towards a given goal but that it is not involved when navigational representations based on the geometrical shape of the environment or the coding of body movements are sufficient for memorizing and recalling short pathways
Inside the Virtuous Cycle between Productivity, Profitability, Investment and Corporate Growth: An Anatomy of China Industrialization
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