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We used a large-scale data-driven approach to investigate the role of word form in accessing semantics. By using distributional semantic methods and taking advantage of an ERP lexical decision mega-study, we investigated the exact time dynamic of semantic ac-cess from printed words as driven by orthography-semantics consistency (OSC) and phonology-semantics consistency (PSC). Generalized Additive Models revealed very early and late OSC-by-PSC interactions, visible at 100 and 400 msec, respectively. This pattern suggests that, during visual word recognition: a) meaning is accessed by means of two distinct and interactive paths -the orthography-to-meaning and the orthography-to -phonology-to-meaning path-, which mutually contribute to recognition since early stages; b) the system may exploit a dual mechanism for semantic access, with early and late effects associated to a fast-coarse and a slow-fine grained semantic analysis, respec-tively. The results also highlight the high sensitivity of the visual word recognition system to arbitrary form-meaning relations.(c) 2022 Elsevier Ltd. All rights reserved.

Background: Cognitive screening tests (CSTs) are crucial to neuropsychological diagnostics, and thus need to be featured by robust psychometric and diagnostic properties. However, CSTs happen not to meet desirable statistical standards, negatively affecting their level of recommendations and applicability. This study aimed at (a) providing an up-to-date compendium of available CSTs in Italy, (b) report their psychometric and diagnostic properties, and (c) address related limitations. Methods: This review was implemented by consulting Preferred Reporting Items for Systematic Reviews and Meta-Analyses and pre-registered on the International Prospective Register of Systematic Reviews. Standardization and usability studies focusing on norms, validity, reliability, or sensitivity/specificity (and derived metrics) in adults were considered for eligibility. Quality assessment was performed by means of an ad hoc checklist collecting information on sampling, psychometrics/diagnostics, norming, and feasibility. Results: Sixty studies were included out of an initial N = 683. Identified CSTs (N = 40) were classified into general, domain-, and disease-specific (N = 17, 7, and 16, respectively), the latter being less statistically robust than remaining categories. Validity and reliability evidence was provided for 29 and 26 CSTs, respectively, sensitivity/specificity for 20 and norms for 33. Prevalence- and post-test-based diagnostic metrics were seldomly represented; factorial structures, ceiling/floor effects, and acceptability rarely investigated; content, face, and ecological validity never assessed. Discussion: Although available Italian CSTs overall met basic psychometric/diagnostic requirements, their statistical profile often proved to be poor on several properties that are desirable for clinical applications, with a few exceptions among general and domain-specific ones.

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique able to induce plasticity phenomena. Although tDCS application has been spreading over a variety of neuroscience domains, the mechanisms by which the stimulation acts are largely unknown. We investigated tDCS effects on cortical gamma synchrony, which is a crucial player in cortical function. We performed a randomized, sham-controlled, double-blind study on healthy subjects, combining tDCS and magnetoencephalography. By driving brain activity via 40 Hz auditory stimulation during magnetoencephalography, we experimentally tuned cortical gamma synchrony and measured it before and after bilateral tDCS of the primary sensory-motor hand regions (anode left, cathode right). We demonstrated that the stimulation induces a remarkable decrease of gamma synchrony (13 out of 15 subjects), as measured by gamma phase at 40 Hz. tDCS has strong remote effects, as the cortical region mostly affected was located far away from the stimulation site and covered a large area of the right centro-temporal cortex. No significant differences between stimulations were found for baseline gamma synchrony, as well as early transient auditory responses. This suggests a specific tDCS effect on externally driven gamma synchronization. This study sheds new light on the effect of tDCS on cortical function showing that the net effect of the stimulation on cortical gamma synchronization is an inhibition.

Humans can communicate information on numerosity by means of number words (e.g. one hundred, a couple), but also through Number morphology (e.g. through the singular vs. the plural forms of a noun). Agreement violations involving Number morphology (e.g. *one apples) are well known to elicit specific ERP components such as the Left Anterior Negativity (LAN); yet, the relationship between a morphological Number value (e.g. singular vs. plural) and its referential numerosity has been scantly considered in the literature. Moreover, even if agreement violations have been proved very useful, they do not typically characterise the everyday language usage, thus narrowing the scope of the results. In this study we investigated Number morphology from a different perspective, by focusing on the ERP correlates of congruence and incongruence between a depicted numerosity and noun phrases. To this aim we designed a picture–phrase matching paradigm in Italian. In each trial, a picture depicting one or four objects was followed by a grammatical phrase made up of a quantifier and a content noun inflected either in the singular or in the plural. When analysing ERP time-locked to the content noun, plural phrases after pictures presenting one object elicited a larger negativity, similar to a LAN effect. No significant congruence effect was found in the case of the phrases whose morphological Number value conveyed a numerosity of one. Considering the LAN as an index of morpho-syntactic incongruence, these results suggest that 1) LAN-like effects can be triggered independently from the grammaticality of the utterances and irrespective the P600 component; 2) the reference to a numerosity can be partially encoded in an incremental way when processing Number morphology; and, most importantly, 3) the processing of the morphological Number value of plural is different from that of singular as the former shows a narrower interpretability than the latter.