1,720,969 research outputs found
Tes and its Effects on Cognitive FUnctions: Feasibility and Limitations for a Broader Clinical Application
Full text linkTrascranial electrical stimulation (tES) is a neuromodulation technique which applies a mild current to modulate a wide variety of cognitive functions. It was shown that depending on the protocol applied, tES is effective in enhancing or interfering with cortical excitation, even if further research is needed in order to better understand its effects. In our studies, we focused on the online or offline effects of various tES protocols and on disparate tasks, in order to evaluate potential future application on clinical population. To date, few studies investigated offline, transfer effects of tES, both after single or multiple sessions administration. Similarly, evidence assessing tES offline and long-term effects on cortical excitability is still lacking.
This doctoral thesis contributed to shed light on different aspects concerning tES. Firstly, we demonstrated that cathodal tDCS applied over right inferior frontal gyrus (rIFG) is effective in modulating selectively incongruent trials in a dots comparison task. Moreover, the effect was specific for offline measures, but not online, suggesting possible short-term after-effects of this protocol. Secondly, we showed that bilateral tRNS is more effective than anodal tDCS in inducing after-stimulation changes in attention both on behavioral performance and cortical excitation. Our studies confirmed that the two protocols are differentially effective, consistently with literature showing that different neural mechanisms underlie tDCS and tRNS neural after-effects. Finally, we demonstrated that despite the absence of online effects, coupling bilateral tRNS with cognitive training is effective to induce long-term changes, as assessed by behavioral measures and cortical plasticity investigations. Interestingly, the effects were still present a month after the end of the training. Taken together, our studies contributed to better understand the after-effects of tES and suggests that bilateral tRNS is best suited for clinical applications, even if further research is needed
Trait-related neural basis of attentional bias to emotions: a tDCS study
Full text linkNegative emotional stimuli can strongly bias attention, particularly in individuals with high levels of dispositional negative affect (NA). The current study investigated whether the prefrontal cortex (PFC), a brain region involved in the top-down regulation of emotional processing, plays a different role in controlling attention to emotions, depending on the individual NA. Sham and anodal transcranial direct current stimulation (tDCS) was delivered over the right or left PFC while assessing attentional bias (AB) to emotions (happy, angry, sad faces) in individuals with higher and lower trait NA. When tDCS was inactive (sham), individuals with higher trait NA showed AB toward angry and away from sad faces, while individuals with lower trait NA presented with no AB. Right anodal-tDCS abolished the AB toward angry faces and induced an AB toward sad faces in individuals with higher trait NA, while no effect was found in individuals with lower trait NA. Left anodal-tDCS abolished any AB in individuals with higher trait NA and induced an AB away from happy faces in individuals with lower trait NA. These findings confirm a critical role of trait NA in AB to emotions and demonstrate a different involvement of PFC in emotional processing based on dispositional affect
Neuromodulation and attentional abilities: different trasfer outcomes of tDCS and tRNS.
Full text linkEffetti modulatori della tDCS sulla corteccia prefrontale dorsolaterale destra (rDLPFC) nel Retrieval-induced forgetting
No full textAttentional bias to emotions after prolonged endurance exercise is modulated by age
No full textPhysical exercise has an impact in biasing attention to positive or negative emotional stimuli. While attentional shift to emotions varies with age, evidence is lacking on the effect of prolonged endurance exercise on age-related attentional bias to emotions. This study aims at filling this knowledge gap, by applying a dot-probe task to measure attentional bias to emotions before and after a half-marathon in healthy participants of different ages (age range 21-65 years). State anxiety, positive and negative affect were also assessed. Younger adults showed attentional bias towards anger and away from sadness after the race, supporting the hypothesis of the congruency between the high-arousing task and the associated emotion (anger) in the modulation of attention. Conversely, older adults showed a bias away from anger, likely representing an attempt to maintain an optimal emotional level after the competition. This study sheds new light on how age impacts on emotional mechanisms involved in prolonged endurance exercise and suggests that regulatory processes in response to stress may be involved differently, depending on age
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
Chapter 11 - The motor system and motor disorders
No full textThe beneficial effects of placebos and the harmful effects of nocebos on motor functions concern not only sports performance but also pathological conditions and, in particular, movement disorders. In the pathological context, most studies have been conducted on Parkinson disease, where placebo and nocebo can influence motor and nonmotor symptoms, modulate the activity of subcortical and cortical brain regions, and, in the case of placebos, induce the dopaminergic release in the basal ganglia. In contrast, knowledge about placebo and nocebo effects in other movement disorders is still limited and derives mainly from randomized control studies in which the term "placebo response" is more appropriate than "placebo effect." As will be illustrated in this chapter, the study of placebo and nocebo effects in the motor domain has addressed different motor functions involving more focused body districts or the entire body and has allowed discovering the involvement of a set of cortical and subcortical brain structures belonging to the motor control network
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
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