1,720,966 research outputs found
Transcranial direct current stimulation of the medial prefrontal cortex dampens mind-wandering in men
Full text linkMind-wandering, the mind's capacity to stray from external events and generate task-unrelated thought, has been associated with activity in the brain default network. To date, little is understood about the contribution of individual nodes of this network to mind-wandering. Here, we investigated the role of medial prefrontal cortex (mPFC) in mind-wandering, by perturbing this region with transcranial direct current stimulation (tDCS). Young healthy participants performed a choice reaction time task both before and after receiving cathodal tDCS over mPFC, and had their thoughts periodically sampled. We found that tDCS over mPFC - but not occipital or sham tDCS - decreased the propensity to mind-wander. The tDCS-induced reduction in mind-wandering occurred in men, but not in women, and was accompanied by a change in the content of task-unrelated though, which became more related to other people (as opposed to the self) following tDCS. These findings indicate that mPFC is crucial for mind-wandering, possibly by helping construction of self-relevant scenarios capable to divert attention inward, away from perceptual reality. Gender-related differences in tDCS-induced changes suggest that mPFC controls mind-wandering differently in men and women, which may depend on differences in the structural and functional organization of distributed brain networks governing mind-wandering, including mPFC
Relazione tra Inibizione Comportamentale valutata da madri e insegnanti e competenze metafonologiche.
No full textA test for the evaluation of form perception ability: Form Coherence Test
No full textThe aim of this study is the assessment of the applicability of the Form Coherence Test in a population of infants and adolescents. The Form Coherence Test is a computerized test for the evaluation of form perception ability. The subject is asked to discriminate a shape-stimulus among eight possible forms. The form perception is obtained by spatial coherent luminance dots visualized on a black background. Stimuli are presented in five levels of coherence which determines the difficulty of the task: starting from the 100% of coherence level, the number 1 of the coherently aligned dots exponentially decreases while the number of non-coherent dots (noise) increases. A sample of two hundred and fifty children (range 5-12 years) took part in the study. Accuracy is measured as the number of correct answers for each coherence level and for each stimulus. The Generalized Estimating Equation Model shows that the form perception accuracy decreased significantly in the subsequent coherence levels, starting from the 100% to 45%. The number of correct answers raised significantly with age. Age also affects the identification of the eight forms characterized by different difficulty. The results showed that Form Coherence Test is an instrument appropriate for the considered ages and allowed to evaluate the subject’s performance at different coherence level taking into account the age
How are preschool children perceived? Relations among behavioural inhibition, temperament and cognitive performances
No full textThe present work aims at verifying the existence of such relations, focusing attention on the Behavioural Inhibition (BI) temperamental trait, recognised in literature as a risk factor for the development of social phobia in adolescence (Biederman et al., 2001; Rotge et al., 2011). The sample consists of 100 3 to 5 year old children and the teachers and parents. Direct measurements on the child were used to assess cognitive abilities (IQ and linguistic abilities) and the perceptions of teachers and parents, regarding child temperament and Behavioural Inhibition, were assessed and compared. The instruments used were the Behavioural Inhibition Questionnaire (Bishop et al., 2003), the Italian Questionnaires of Temperament (Axia, 2002), the Raven’s Coloured Progressive Matrices (Raven et al., 1998), two subscales from the Metaphonological Competences (Marotta et al., 2008), and the Non-Word Repetition (Vicari, 2008). The results suggest the parents and teachers have a significantly different perception of children, regarding certain temperamental dimensions. The teachers perceive the children as having a higher level of Behavioural Inhibition and Attention, compared to the perception of parents, while the former describe the children as having higher levels of Inhibition towards Novelty, Negative Emotionality and Motor Activity. Regarding cognitive abilities, children with a higher IQ are perceived as less inhibited towards noveltyby mothers and teachers. In summary, the difference in perception between parents and teachers could be hypothesised to be tied to the different observational context and to the different role, which might indicate a more complete perception of child temperament in teachers. Further research is needed to better study these aspects
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
