Perceptual facilitation of word recognition through motor activation during sentence comprehension

Published online 29 July 2018Despite the growing literature on anticipatory language processing, the brain dynamics of this high-level predictive process are still unclear. In the present MEG study, we analyzed pre- and post-stimulus oscillatory activity time-locked to the reading of a target word. We experimentally contrasted the processing of the same target word following two highly constraining sentence contexts, in which the constraint was driven either by the semantic content or by the lexical association between words. Previous research suggests the presence of sensory facilitation for expected words in the latter condition but not in the former. We observed a dissociation between beta (∼20 Hz) and gamma (>50 Hz) band activity in pre- and post-stimulus time intervals respectively. Both the beta and gamma effects were evident in occipital brain regions, and only the pre-stimulus beta effect additionally involved left pre-articulatory motor regions. Lexically constrained (vs. semantically constrained) words elicited reduced beta power around 400 msec before the target word in motor regions and a functionally related gamma enhancement in occipital regions around 200 msec post-target. The present findings highlight the role of the motor network in word-form prediction and support proposals claiming that low-level perceptual representations can be pre-activated during language prediction.This work was partially supported by the Spanish Ministry of Economy and Competitiveness (MINECO), the Agencia Estatal de Investigación (AEI) and the (Fondo Europeo de Desarrollo Regional FEDER) (grant PSI2015-65694-P, “Severo Ochoa” programme SEV-2015-490 for Centres of Excellence in R&D), and by the Basque government (grant PI_2016_1_0014). Further support derived from the AThEME project funded by the European Commission 7th Framework Programme, the ERC- 2011-ADG-295362 from the European Research Council

Colour and stellar population gradients in galaxies

We discuss the colour, age and metallicity gradients in a wide sample of local SDSS early- and late-type galaxies. From the fitting of stellar population models we find that metallicity is the main driver of colour gradients and the age in the central regions is a dominant parameter which rules the scatter in both metallicity and age gradients. We find a consistency with independent observations and a set of simulations. From the comparison with simulations and theoretical considerations we are able to depict a general picture of a formation scenario.Comment: 4 pages, 4 figures. Proceedings of 54th Congresso Nazionale della SAIt, Napoli 4-7 May 201

Theta oscillations mediate preactivation of highly expected word initial phonemes

Published: 22 June 2018Prediction has been proposed to be a fundamental neurocognitive mechanism. However, its role in language comprehension is currently under debate. In this magnetoencephalography study we aimed to find evidence of word-form phonological pre-activation and to characterize the oscillatory mechanisms supporting this. Participants were presented firstly with a picture of an object, and then, after a delay (fixed or variable), they heard the corresponding word. Target words could contain a phoneme substitution, and participants’ task was to detect mispronunciations. Word-initial phonemes were either fricatives or plosives, generating two experimental conditions (expect-fricative and expect-plosive). In the pre-word interval, significant differences (α = 0.05) emerged between conditions both for fixed and variable delays. Source reconstruction of this effect showed a brain-wide network involving several frequency bands, including bilateral superior temporal areas commonly associated with phonological processing, in a theta range. These results show that phonological representations supported by the theta band may be active before word onset, even under temporal uncertainty. However, in the evoked response just prior to the word, differences between conditions were apparent under variable- but not fixed-delays. This suggests that additional top-down mechanisms sensitive to phonological form may be recruited when there is uncertainty in the signal.This work was partially supported by the Spanish Ministry of Economy and Competitiveness (MINECO), the Agencia Estatal de Investigación (AEI), the Fondo Europeo de Desarrollo Regional FEDER) (grant PSI2016– 77175-P to Mathieu Bourguignon, grant PSI2015–65694-P to Nicola Molinaro, Severo Ochoa programme SEV-2015–490 for Centres of Excellence in R&D), and by the Basque government (grant PI_2016_1_0014 to Nicola Molinaro). Further support derived from the AThEME project funded by the European Commission 7th Framework Programme, the ERC- 2011-ADG-295362 from the European Research Council. Finally, Mathieu Bourguignon was supported by the program Attract of Innoviris (grant 2015-BB2B-10) and by the Marie Skłodowska-Curie Action of the European Commission (grant 743562)

Full, hybrid and platform complementarity: Exploring the industry 4.0 technology-performance link

Literature has increasingly recognized that manufacturing companies should implement a synergic bundle of solutions to fully exploit the potential of Industry 4.0 (I4.0), rather than opting for a scattered technological adoption. Enabling I4.0 technologies, such as cloud computing, artificial intelligence, and additive manufacturing, can be implemented through various combinations to achieve different impacts on a company's performance. But what are the possible ways of combining I4.0 technologies into bundles, and do these ways actually help to achieve a performance that outperforms the adoption of single technologies? This study aims to identify the potential patterns of the technological complementary of I4.0 by considering enabled applications and performance outcomes. We interviewed 13 Italian experts in the I4.0 field, and then combined the obtained information with secondary data collected from more than 150 I4.0 use cases, as well as from websites, reports and press releases. By adopting a systems theory lens, the results of the analysis have allowed us to identify the specific performance effects of both scattered and joint technological adoptions in different application areas. Interestingly, specific examples of I4.0 complementarities emerged, namely full, hybrid and platform complementarity. This study contributes to the growing research on I4.0 outcomes by extending the concept of technological complementary within the I4.0 context. Results show that bundles of technologies have a broader effect on performance than when the same technologies are adopted in isolation, but also that single technologies can impact specific applications and the overall performance of a firm via a systematic I4.0 transformation path

Item parameters dissociate between expectation formats: a regression analysis of time-frequency decomposed EEG data

During language comprehension, semantic contextual information is used to generate expectations about upcoming items. This has been commonly studied through the N400 event-related potential (ERP), as a measure of facilitated lexical retrieval. However, the associative relationships in multi-word expressions (MWE) may enable the generation of a categorical expectation, leading to lexical retrieval before target word onset. Processing of the target word would thus reflect a target-identification mechanism, possibly indexed by a P3 ERP component. However, given their time overlap (200–500 ms post-stimulus onset), differentiating between N400/P3 ERP responses (averaged over multiple linguistically variable trials) is problematic. In the present study, we analyzed EEG data from a previous experiment, which compared ERP responses to highly expected words that were placed either in a MWE or a regular non-fixed compositional context, and to low predictability controls. We focused on oscillatory dynamics and regression analyses, in order to dissociate between the two contexts by modeling the electrophysiological response as a function of item-level parameters. A significant interaction between word position and condition was found in the regression model for power in a theta range (~7–9 Hz), providing evidence for the presence of qualitative differences between conditions. Power levels within this band were lower for MWE than compositional contexts when the target word appeared later on in the sentence, confirming that in the former lexical retrieval would have taken place before word onset. On the other hand, gamma-power (~50–70 Hz) was also modulated by predictability of the item in all conditions, which is interpreted as an index of a similar “matching” sub-step for both types of contexts, binding an expected representation and the external input

Prony model with time varying poles

This communication proposes a new Prony model with time-varying poles fo r modelisation of nonstationary signals. This new model is based upon a linea r combination of time–varying exponentials. This method leads to an extension of several techniques of stationary spectral estimation to the nonstationary case : amplitude and phase are time–varying. We show and justify a method and th e corresponding algorithm to estimate the complete new parameter vector. The determination of the time–varying parameters requires five steps : estimation of the time–varying AR parameters, estimation of the right poles of the linear time – varying system, modelisation of these poles, computation of the new poles, and least–square estimation of the amplitudes . To validate this model, a simulation signal composed of two chirps is chosen .L'article propose un nouveau modèle de Prony à pôles dépendant du temps pour modéliser des signaux non stationnaires. Ce modèle est basé sur une combinaison linéaire d'exponentielles complexes à coefficients variant avec le temps. Il est une extension des techniques d'estimation spectrale appliquée dans le cas stationnaire : l'amplitude et la phase du signal varient avec le temps. Nous présentons et justifions une méthode avec l'algorithme correspondant pour estimer complètement les paramètres du modèle. Le calcul des paramètres dépendant du temps nécessite cinq étapes : l'estimation des paramètres autorégressifs (AR) variant avec le temps, l'estimation des pôles à droite, la modélisation de ces pôles, le calcul des nouveaux pôles et l'estimation avec une méthode des moindres carrés des facteurs d'amplitudes. Pour valider le modèle, une simulation est effectuée sur un signal à deux composantes de loi en fréquence variant linéairement avec le temps

Exoneration or Observation? Examining a Novel Difference Between Liars and Truth Tellers

Individual cues to deception are subtle and often missed by lay people and law enforcement alike. Linguistic statement analysis remains a potentially useful way of overcoming individual diagnostic limitations (e.g. Criteria based Content Analysis; Steller & Köhnken, 1989; Reality monitoring; Johnson & Raye, 1981; Scientific Content Analysis; Sapir, 1996). Unfortunately many of these procedures are time-consuming, require in-depth training, as well as lack empirical support and/or external validity. The current dissertation develops a novel approach to statement veracity analysis that is simple to learn, easy to administer, theoretically sound, and empirically validated. Two strategies were proposed for detecting differences between liars\u27 and truth-tellers\u27 statements. Liars were hypothesized to strategically write statements with the goal of self-exoneration. Liars\u27 statements were predicted to contain more first person pronouns and fewer third person pronouns. Truth-tellers were hypothesized to be motivated toward being informative and thus produce statements with fewer first person pronouns and more third person pronouns. Three studies were conducted to test this hypothesis. The first study explored the verbal patterns of exoneration and informativeness focused statements. The second study used a traditional theft paradigm to examine these verbal patterns in guilty liars and innocent truth tellers. In the third study to better match the context of a criminal investigation a cheating paradigm was used in which spontaneous lying was induced and written statements were taken. Support for the first person pronoun hypothesis was found. Limited support was found for the third person pronoun hypothesis. Results, implications, and future directions for the current research are discussed