Semantic Stroop interference is modulated by the availability of executive resources: Insights from delta-plot analyses and cognitive load manipulation.

We investigated whether, during visual word recognition, semantic processing is modulated by attentional control mechanisms directed at matching semantic information with task-relevant goals. In previous research, we analyzed the semantic Stroop interference as a function of response latency (delta-plot analyses) and found that this phenomenon mainly occurs in the slowest responses. Here, we investigated whether this pattern is due to reduced ability to proactively maintain the task goal in these slowest trials. In two pairs of experiments, participants completed two semantic Stroop tasks: a classic semantic Stroop task (Experiment 1A and 2A) and a semantic Stroop task combined with an n-back task (Experiment 1B and 2B). The two pairs of experiments only differed in the trial pace, which was slightly faster in Experiments 2A and 2B than in Experiments 1A and 1B. By taxing the executive control system, the n-back task was expected to hinder proactive control. Delta-plot analyses of the semantic Stroop task replicated the enhanced effect in the slowest responses, but only under sufficient time pressure. Combining the semantic Stroop task with the n-back task produced a change in the distributional profile of semantic Stroop interference, which we ascribe to a general difficulty in the use of proactive control. Our findings suggest that semantic Stroop interference is, to some extent, dependent on the available executive resources, while also being sensitive to subtle variations in task conditions.

Fast habituation to semantic interference generated by taboo connotation in reading aloud.

The recognition of taboo words - i.e. socially inappropriate words - has been repeatedly associated to semantic interference phenomena, with detrimental effects on the performance in the ongoing task. In the present study, we investigated taboo interference in the context of reading aloud, a task configuration which prompts the overt violation of conventional sociolinguistic norms by requiring the explicit utterance of taboo items. We assessed whether this form of semantic interference is handled by habituative or cognitive control processes. In addition to the reading aloud task, participants performed a vocal Stroop task featuring different conditions to dissociate semantic, task, and response conflict. Taboo words were read slower than non-taboo words, but this effect was subject to a quick habituation, with a decreasing interference over the course of trials, which allowed participants to selectively attend to goal-relevant information. In the Stroop task, only semantic conflict was significantly reduced by habituation. These findings suggest that semantic properties can be quickly and flexibly weighed on the basis of contextual appropriateness, thus characterising semantic processing as a flexible and goal-directed component of reading aloud.

Taboo language across the globe: A multi-lab study.

The use of taboo words represents one of the most common and arguably universal linguistic behaviors, fulfilling a wide range of psychological and social functions. However, in the scientific literature, taboo language is poorly characterized, and how it is realized in different languages and populations remains largely unexplored. Here we provide a database of taboo words, collected from different linguistic communities (Study 1, N = 1046), along with their speaker-centered semantic characterization (Study 2, N = 455 for each of six rating dimensions), covering 13 languages and 17 countries from all five permanently inhabited continents. Our results show that, in all languages, taboo words are mainly characterized by extremely low valence and high arousal, and very low written frequency. However, a significant amount of cross-country variability in words' tabooness and offensiveness proves the importance of community-specific sociocultural knowledge in the study of taboo language.

Form to meaning mapping and the impact of explicit morpheme combination in novel word processing.

In the present study, we leveraged computational methods to explore the extent to which, relative to direct access to semantics from orthographic cues, the additional appreciation of morphological cues is advantageous while inducing the meaning of affixed pseudo-words. We re-analyzed data from a study on a lexical decision task for affixed pseudo-words. We considered a parsimonious model only including semantic variables (namely, semantic neighborhood density, entropy, magnitude, stem proximity) derived through a word-form-to-meaning approach (ngram-based). We then explored the extent to which the addition of equivalent semantic variables derived by combining semantic information from morphemes (combination-based) improved the fit of the statistical model explaining human data. Results suggest that semantic information can be extracted from arbitrary clusters of letters, yet a computational model of semantic access also including a combination-based strategy based on explicit morphological information better captures the cognitive mechanisms underlying human performance. This is particularly evident when participants recognize affixed pseudo-words as meaningful stimuli.

Formant-invariant voice and pitch representations are pre-attentively formed from constantly varying speech and non-speech stimuli.

The present study investigated whether listeners can form abstract voice representations while ignoring constantly changing phonological information and if they can use the resulting information to facilitate voice change detection. Further, the study aimed at understanding whether the use of abstraction is restricted to the speech domain or can be deployed also in non-speech contexts. We ran an electroencephalogram (EEG) experiment including one passive and one active oddball task, each featuring a speech and a rotated speech condition. In the speech condition, participants heard constantly changing vowels uttered by a male speaker (standard stimuli) which were infrequently replaced by vowels uttered by a female speaker with higher pitch (deviant stimuli). In the rotated speech condition, participants heard rotated vowels, in which the natural formant structure of speech was disrupted. In the passive task, the mismatch negativity was elicited after the presentation of the deviant voice in both conditions, indicating that listeners could successfully group together different stimuli into a formant-invariant voice representation. In the active task, participants showed shorter reaction times (RTs), higher accuracy and a larger P3b in the speech condition with respect to the rotated speech condition. Results showed that whereas at a pre-attentive level the cognitive system can track pitch regularities while presumably ignoring constantly changing formant information both in speech and in rotated speech, at an attentive level the use of such information is facilitated for speech. This facilitation was also testified by a stronger synchronisation in the theta band (4-7 Hz), potentially pointing towards differences in encoding/retrieval processes.

Synaptic plasticity mechanisms behind TMS efficacy: insights from its application to animal models.

Neural plasticity is defined as a reshape of communication paths among neurons, expressed through changes in the number and weights of synaptic contacts. During this process, which occurs massively during early brain development but continues also in adulthood, specific brain functions are modified by activity-dependent processes, triggered by external as well as internal stimuli. Since transcranial magnetic stimulation (TMS) produces a non-invasive form of brain cells activation, many different TMS protocols have been developed to treat neurological and psychiatric conditions and proved to be beneficial. Although neural plasticity induction by TMS has been widely assessed on human subjects, we still lack compelling evidence about the actual biological and molecular mechanisms. To support a better comprehension of the involved phenomena, the main focus of this review is to summarize what has been found through the application of TMS to animal models. The hope is that such integrated view will shed light on why and how TMS so effectively works on human subjects, thus supporting a more efficient development of new protocols in the future.

Different types of semantic interference, same lapses of attention: Evidence from Stroop tasks.

This research investigated the possibility that semantic control mechanisms are recruited only when the interfering semantic information does not overlap with task-relevant semantic dimensions. To reach this goal, we investigated two semantic types of Stroop interference-the semantic and the taboo Stroop effects-and used delta-plots to investigate the role of attentional and semantic control in these two interference phenomena. The semantic Stroop effect, where interference stems from the task-relevant color-related information, was absent in faster responses, whereas it steeply increased in the slowest ones. Contrary to our predictions, the same pattern was detected even for the taboo Stroop interference, with no trace of selective suppression of the interfering semantic connotation, despite its dissociation from any task-relevant semantic dimension. Further, there was a significant correlation between the increase of the two effects in the slowest responses, pointing towards a common underlying processing dynamic. We identified such common background with lapses of executive attention in maintaining task goals and schema, which in turn make the participants performance more prone to interference phenomena. Finally, the absence of any interference effects in the fastest responses suggests that an effective filtering of the distracting word stimuli can be implemented in the context of Stroop paradigms.

Tune in to the right frequency: Theta changes when distancing from emotions elicited by unpleasant images and words.

Emotion regulation allows humans to successfully modulate their reactions to life events. Whether regulation strategies may alter brain oscillatory activity and how they are influenced by format and emotional dimensions is still under debate. We investigated oscillatory brain dynamics during the implementation of the strategy of Distancing and during the regulation of the emotions elicited by neutral and unpleasant pictures and, for the first time, words. When implementing the strategy, an early increase in theta band in posterior regions was observed (Effect of Strategy). We interpret this effect as a marker of emotion regulation, and we suggest an integrative framework of the role of theta on regulatory processes. When regulating the emotional impact elicited by stimuli, a decrease in the theta and beta bands in posterior regions for pictures, but not for words, was observed (Effect of Regulation). Behaviorally, the Effect of Regulation was evident for both pictures and words and more pronounced for Valence than for Arousal. These results contribute to better understand the neural and behavioral features of Distancing (both Effect of Strategy and of Regulation), and open up the possibility to clarify which strategy works better to modulate specific stimulus types and emotional dimensions.

The impact of emotional content on pseudoword recognition.

The present study investigates the influence of emotional information on language processing. To this aim, we measured behavioral responses and event-related brain potentials (ERPs) during four Italian lexical decision experiments in which we used emotionally intense and neutral pseudowords-i.e., pseudowords derived from changing one letter in a word (e.g., cammelto, derived from cammello 'camel' vs. copezzolo, from capezzolo 'nipple')-as stimuli. In Experiment 1 and 2, half of the pseudowords were emotionally intense and half were neutral, and were mixed with neutral words. In Experiment 3, the list composition was manipulated, with » of the pseudowords being derived from emotionally intense words and ¾ derived from neutral words. Experiment 4 was identical to Experiment 1, but ERPs were recorded. Emotionally intense pseudowords were categorized more slowly than neutral pseudowords, with the difference emerging both in the mean and at the leading edge of the response times distribution. Moreover, emotionally intense pseudowords elicited smaller N170 and N400 than neutral pseudowords. These results speak in favor of a fast and multi-level infiltration of the emotional information into the linguistic process of word recognition.

On the Boundaries between Decision and Action: Effector-selective Lateralization of Beta-frequency Power Is Modulated by the Lexical Frequency of Printed Words.

Current computational and neuroscientific models of decision-making posit a discrete, serial processing distinction between upstream decisional stages and downstream processes of motor-response implementation. We investigated this framework in the context of two-alternative forced-choice tasks on linguistic stimuli, words and pseudowords. In two experiments, we assessed the impact of lexical frequency and action semantics on two effector-selective EEG indexes of motor-response activation: the lateralized readiness potential and the lateralization of beta-frequency power. This allowed us to track potentially continuous streams of processing progressively mapping the evaluation of linguistic stimuli onto corresponding response channels. Whereas action semantics showed no influence on EEG indexes of motor-response activation, lexical frequency affected the lateralization of response-locked beta-frequency power. We argue that these observations point toward a continuity between linguistic processing of word input stimuli and implementation of corresponding choice in terms of motor behavior. This interpretation challenges the commonly held assumption of a discrete processing distinction between decisional and motor-response processes in the context of decisions based on symbolic stimuli.

Bilingualism as a gradient measure modulates functional connectivity of language and control networks.

There is currently no agreement on which factor modulates most effectively and enduringly brain plasticity in bilingual individuals. Grouping heterogeneous linguistic profiles under a dichotomous condition (bilingualism versus monolingualism) may obscure critical aspects of language experience underlying neural changes, thus leading to variable and often conflicting findings. In the present study, we overcome these limitations by analyzing the individual and joint contribution of L2 AoA, proficiency and usage - all measured as continuous variables - on the resting-state functional connectivity of the brain networks mediating the specific demands of bilingual language processing: the language network and the executive control network. Our results indicate that bilingual experience - defined as a continuous and multifaceted phenomenon - impacts brain plasticity by modulating the functional connectivity both within and between language and control networks. Each experience-related factor considered played a role in changing the connectivity of these regions. Moreover, the effect of AoA was modulated by proficiency and usage. These findings shed new light on the importance of modeling bilingualism as a gradient measure rather than an all-or-none phenomenon.

ACC Sulcal Patterns and Their Modulation on Cognitive Control Efficiency Across Lifespan: A Neuroanatomical Study on Bilinguals and Monolinguals.

The anterior cingulate cortex (ACC) is a key structure implicated in the regulation of cognitive control (CC). Previous studies suggest that variability in the ACC sulcal pattern-a neurodevelopmental marker unaffected by maturation or plasticity after birth-is associated with intersubject differences in CC performance. Here, we investigated whether bilingual experience modulates the effects of ACC sulcal variability on CC performance across the lifespan. Using structural MRI, we first established the distribution of the ACC sulcal patterns in a large sample of healthy individuals (N = 270) differing on gender and ethnicity. Second, a participants' subsample (N = 157) was selected to test whether CC performance was differentially affected by ACC sulcation in bilinguals and monolinguals across age. A prevalent leftward asymmetry unaffected by gender or ethnicity was reported. Sulcal variability in the ACC predicted CC performance differently in bilinguals and monolinguals, with a reversed pattern of structure-function relationship: asymmetrical versus symmetrical ACC sulcal patterns were associated with a performance advantage in monolinguals and a performance detriment to bilinguals and vice versa. Altogether, these findings provide novel insights on the dynamic interplay between early neurodevelopment, environmental background and cognitive efficiency across age.

Gay Voice: Stable Marker of Sexual Orientation or Flexible Communication Device?

Listeners rely on vocal features when guessing others' sexual orientation. What is less clear is whether speakers modulate their voice to emphasize or to conceal their sexual orientation. We hypothesized that gay individuals adapt their voices to the social context, either emphasizing or disguising their sexual orientation. In Study 1 (n = 20 speakers, n = 383 Italian listeners and n = 373 British listeners), using a simulated conversation paradigm, we found that gay speakers modulated their voices depending on the interlocutor, sounding more gay when speaking to a person with whom they have had an easy (vs. difficult or no) coming out. Although straight speakers were always clearly perceived as heterosexual, their voice perception also varied depending on the interlocutor. Study 2 (n = 14 speakers and n = 309 listeners), comparing the voices of young YouTubers before and after their public coming out, showed a voice modulation as a function of coming out. The voices of gay YouTubers sounded more gay after coming out, whereas those of age-matched straight control male speakers sounded increasingly heterosexual over time. Combining experimental and archival methods, this research suggests that gay speakers modulate their voices flexibly depending on their relation with the interlocutor and as a consequence of their public coming out.

Outgroup faces hamper word recognition.

The present study explores socio-cultural priming in native-language processing. Caucasian Italian native speakers completed a written lexical decision task. Written stimuli were preceded by either a prime "white" face (ingroup condition) or a prime "black" face (outgroup condition). Face priming effects were observed in three experiments using different stimuli. Participants were slower in categorizing words, but not non-words, when preceded by an outgroup face than by an ingroup face. Several psycholinguistic variables were manipulated to localize the levels of processing that are affected by socio-cultural prime. The lack of effect with non-word items excludes the possibility that the face priming effect arises at perceptual or attentive levels of processing. In addition, we observed that while the face priming effect does not interact with lexical dimensions, it does interact with a semantic dimension such as imageability. The results indicate that social categories extracted from faces may modulate lexico-semantic processing. Interestingly, such a modulation would occur in the context of a quick and automatic process like visual word recognition in a person's native language.

The developmental trend of transposed letters effects in masked priming.

In the current study, we investigated the development of transposed letter (TL) priming effects with masked priming. Recent studies have reported different and contrasting results concerning the age at which TL priming effects first appear and whether they tend to decline or increase with age. One of the aims of this study was to investigate the developmental trend of orthographic mechanisms underlying the TL effects in Italian. We tested three groups of children (second, third, and fifth graders) and a group of adults with a sandwich masked priming procedure, presenting lists of target words preceded by TL or replaced letter (RL) primes. TLs and RLs were either at the beginning (second-third letters) or the end (fourth-sixth letters) of primes in order to see whether the TL priming effect varied according to position in the letter string. We found that TL priming effects increased with age in both accuracy and latency. No effect of position was found. The results are discussed in light of a possible difference in the development of orthographic mechanisms depending on the transparency of the language.

Neuroplasticity across the lifespan and aging effects in bilinguals and monolinguals.

Evidence that bilingualism protects against age-related neurocognitive decline is mixed. One relatively consistent finding is that bilingual seniors have greater grey matter volume (GMV) in regions implicated in executive control (EC) and language processing. Here, we compare the neuroplastic effects of bilingual experience on the EC network of young and aging populations directly, and for the first time we evaluate the extent to which such effects may predict executive control performance across age. We used GMV as an index of neural reserve and response time (RT) performance on the Flanker task for measuring EC efficiency. In the presence of age-related widespread GM deterioration, bilinguals had greater GMV than monolinguals in key regions of interest across age. Moreover, whereas EC performance in monolingual seniors was strictly related to GMV, this was not observed for bilingual seniors or younger participants in either group. Interactions between expected effects-of-age and language group on the relationships between GMV and RT suggested that bilingualism affords differential benefits across the lifespan. In younger participants, greater GMV offered no behavioral benefit on EC performance, whilst it did for seniors. It thus appears that age-related cognitive decline following GMV loss in the EC network is delayed in bilinguals.

Gay- and Lesbian-Sounding Auditory Cues Elicit Stereotyping and Discrimination.

The growing body of literature on the recognition of sexual orientation from voice ("auditory gaydar") is silent on the cognitive and social consequences of having a gay-/lesbian- versus heterosexual-sounding voice. We investigated this issue in four studies (overall N = 276), conducted in Italian language, in which heterosexual listeners were exposed to single-sentence voice samples of gay/lesbian and heterosexual speakers. In all four studies, listeners were found to make gender-typical inferences about traits and preferences of heterosexual speakers, but gender-atypical inferences about those of gay or lesbian speakers. Behavioral intention measures showed that listeners considered lesbian and gay speakers as less suitable for a leadership position, and male (but not female) listeners took distance from gay speakers. Together, this research demonstrates that having a gay/lesbian rather than heterosexual-sounding voice has tangible consequences for stereotyping and discrimination.

Serial mechanism in transposed letters effects: A developmental study.

The study describes the developmental trend of transposed letters (TL) effects in a lexical decision task. The TL effect refers to the fact that nonwords derived from words by transposing two middle letters (e.g., talbe from table) are responded to more slowly than control nonwords in which two letters are replaced (RL [replaced letters]; e.g., tafde). We measured this effect in three groups of children (second, third, and fifth graders) and a group of adults. Length was manipulated with short letter strings (four or five letters) and long letter strings (seven or eight letters). In long letter strings, position of letter transposition/replacement was also manipulated; half of the stimuli contained the TL/RL toward the beginning of the string and half toward the end of the string. The results showed that the size of the TL effect increased with age and that this developmental pattern was more marked for transpositions involving the final part of the word. The results suggest that with the increase in reading ability, the reading system relies more strongly on a coarse orthographic representation in which letter position is not precisely coded. Furthermore, the effect of position suggests that a serial mechanism is used to scan the letter string. This determines the extent to which nonwords activate the base words, modulating the influence of lexical effects in nonword decisions. The nature of this effect is discussed.

Early markers of lexical stress in visual word recognition.

The goal of the present study was to investigate the time-course of suprasegmental information in visual word recognition. To this aim we measured event-related brain potentials (ERPs) during a simple lexical decision task in Italian. Two factors were manipulated: Stress dominance (the most frequent stress type) and stress neighborhood consistency (the proportion and number of existent words sharing orthographic ending and stress pattern). Participants were presented with target words either bearing dominant (on the penultimate syllable; 'graNIta,' 'seNIle,' slush, senile) or non-dominant stress (on the antepenultimate syllable; 'MISsile,' 'BIbita,' missile, drink), and either having a consistent (graNIta, MISsile) or an inconsistent stress neighborhood (seNIle, BIbita). Our results showed in the initial stages of processing an effect that we interpreted as an early orthographic marker of stress neighborhood in interaction with dominance. Later, from 250 ms after target onset, a marker of the lexical stress difference also emerged. The role of stress assignment in word recognition is discussed.

Analyzing spatial data from mouse tracker methodology: An entropic approach.

Mouse tracker methodology has recently been advocated to explore the motor components of the cognitive dynamics involved in experimental tasks like categorization, decision-making, and language comprehension. This methodology relies on the analysis of computer-mouse trajectories, by evaluating whether they significantly differ in terms of direction, amplitude, and location when a given experimental factor is manipulated. In this kind of study, a descriptive geometric approach is usually adopted in the analysis of raw trajectories, where they are summarized with several measures, such as maximum-deviation and area under the curve. However, using raw trajectories to extract spatial descriptors of the movements is problematic due to the noisy and irregular nature of empirical movement paths. Moreover, other significant components of the movement, such as motor pauses, are disregarded. To overcome these drawbacks, we present a novel approach (EMOT) to analyze computer-mouse trajectories that quantifies movement features in terms of entropy while modeling trajectories as composed by fast movements and motor pauses. A dedicated entropy decomposition analysis is additionally developed for the model parameters estimation. Two real case studies from categorization tasks are finally used to test and evaluate the characteristics of the new approach.