Categorization skills enable animal species to sort entities based on their similarities, providing significant advantages in terms of learning efficiency. The extent of these skills and the mechanisms involved vary across taxa, making it critical to explore categorization in as many lineages as possible. From an evolutionary standpoint, fish are valuable models for studying categorization processes; however, until recently, this group of vertebrates has been neglected in visual categorization research. To address this gap, we conducted three experiments to investigate, for the first time, the visual categorical learning skills of the redtail splitfin (Xenotoca eiseni) and the zebrafish (Danio rerio), two teleost species studied in other contexts of animal cognition. Using a two-alternative forced-choice task, we first trained the fish to discriminate between several pairs of stimuli. Then, we tested their ability to generalize to pairs of new stimuli of the same categories. The stimulus categories varied across the experiments (Experiments 1 and 2: alphanumeric characters; Experiment 3: fish silhouettes) and were consistent with those used in past studies involving different taxa. Both fish species met the learning criterion in the training phase across all three experiments, but their ability to generalize to novel stimuli differed based on stimulus features. Moreover, both species presented interindividual differences in their ability to generalize what they learnt. Our results validate the use of X. eiseni and D. rerio as models for research on categorical learning. They also encourage further investigation into how experimental methods and stimuli could affect learning-based generalization abilities in these species.

The lexical decision paradigm relies on a binary response configuration (word vs. nonword) and a single dichotomous decisional outcome (correct vs. error). The present research used single-trial electromyographic recordings of the responses and metacognitive confidence ratings to gain insight into a) intermediate decisional states and b) potential misalignments between objective and subjective outcomes of the lexical decision process. The results revealed that confidence was high for correct responses, signaling a relatively clear-cut categorization even for more ambiguous stimuli such as low-frequency words and wordlike pseudowords. The dominant factors in shaping metacognitive judgments were stimulus properties and premotor processing time, whereas the contribution of the fluency of the motor responses emerged only under specific conditions. Errors revealed a more complex pattern, with limited conscious detection in the case of ambiguous stimuli. Whereas errors for words were seemingly driven by unresolved decision processes, those for nonwords were mostly determined by lexical competition. Importantly, although these latter errors partially bypassed response control mechanisms, they were more accessible to awareness, pointing to a partial dissociation between error correction and detection. By focusing on the decisional layer of lexical decision, these findings begin to shed light on the specific dynamics that characterize decision-making tasks grounded in memory-based evidence and lexical knowledge.

Does L2 production involve adaptive control? Previous research drawing on a parallel between Stroop effects in L1 and cognate effects in L2 produced no support for this idea when inducing adaptive control implicitly (i.e., involuntarily). Reasoning that adaptive control might be hard to implement implicitly in L2 production, here, we induced adaptive control explicitly by presenting informative cues revealing whether the upcoming stimulus would be congruent/incongruent (in L1 Stroop) or cognate/noncognate (in L2 picture naming). Adaptive control was successfully induced in L1 Stroop, with informative cues, relative to uninformative ones, having a facilitatory effect. Such was not the case for L2 picture naming, in which informative cues had an inhibitory effect. While there might be several reasons for this reverse cueing effect, this finding represents another dissociation between L2 production and conflict tasks, which likely has implications for theories assuming a close connection between domain-general and bilingualism-specific control.

Abstract The experience of making sense of novel words is ubiquitous in human communication. Still, novel words have traditionally been considered as meaningless by cognitive research. Here we combined behavioral, univariate and multivariate fMRI techniques, and computational modelling to explore whether and how novel words activate the neurocognitive hallmarks of semantic processing triggered by existing words, and whether this process is influenced by the presence of familiar functional linguistic elements, i.e., morphemes. We observed that semantic activation for novel words is comparable to that of existing words, provided that novel words contain a concatenation of identifiable morphemes. In addition, representational similarity analysis highlighted that existing words and novel words containing morphemes (but not novel words not containing morphemes) can activate fine-grained semantic representations. These results suggest that the difference in the neurocognitive underpinnings of semantic processing for existing and novel words might be quantitative rather than qualitative and based on how reliably linguistic form points to meaning.

Social interactions are shaped by the way individuals communicate. Listeners form impressions based on how someone sounds, and the message conveyed can be interpreted differently depending on who the speaker is. We investigated on-line sentence processing focusing on the role of the speaker's gay- vs. heterosexual-sounding voice in the construction of meaning. Event-related brain potentials were recorded while participants listened to two gay- and two heterosexual-sounding male speakers uttering stereotypical sentences. We manipulated whether the sentences referred to professions stereotypically congruent or incongruent with the speakers' perceived sexual orientation. Results showed that the interplay between the speaker's voice and message content influenced sentence processing early after an incongruent stereotype was presented. The interaction was maximal at frontal sites, with a larger negativity for stereotypically-congruent than for stereotypically-incongruent professions when uttered by gay-sounding speakers. These results suggest that the perception of the speaker as gay- or straight-sounding is quickly used by listeners to build the message meaning. The inconsistency between vocal and linguistic information modulates a frontal negativity, potentially indicating control processes during sentence comprehension put in place to deal with the inconsistency.

Theories of adaptive (and cognitive) control assume that selecting target information in the context of highly salient distractors depends on limited-capacity resources. Building on this assumption, theories of language-control associations propose that the opportunities afforded by bilingualism to engage such effortful selection, such as when speaking in a nondominant language, might improve domain-general adaptive control. The assumption that domain-general or language-specific selection is resource-demanding, however, has surprisingly little empirical support. Here, we tested that assumption by having unbalanced Italian-English bilinguals perform both an L1 Stroop task and an L2 picture-naming task simultaneously with an n-back task. Both tasks showed costs due to the load produced by the n-back task and distractor interference, with slower responses to incongruent (the word GREEN in the color red) and congruent stimuli (RED in red) than neutral ones (XXX in red) in the L1 Stroop task and to noncognate than cognate pictures (pictures with different/similar L1 and L2 names) in the L2 picture-naming task. However, neither task showed larger distractor interference with greater load, with Bayesian analyses favoring the absence of such interactions. These results suggest that domain-general and language-specific selection may occur reactively, i.e., only when the need arises, with no strong reliance on limited-capacity resources. Further, they invite a rethinking of both adaptive-control theories assuming resource-demanding selection and theories of language-control associations assuming that regularly engaging such selection would be conducive to domain-general benefits.

Recognition is a core component of cognition, yet how we categorize a stimulus as unknown remains an open issue. In this study, we tested whether, during recognition, motor-response execution is affected by the presence vs absence of positive evidence for the to-be-recognized stimulus. Participants performed a visual lexical decision task with five categories of stimuli, varying along a word-likeness gradient: High-frequency words, low-frequency words, letter-substitution pseudowords (derived from real words by changing one letter), pseudowords (non-existing words not resembling any words), and illegal strings of letters. The effect of stimulus category was separately examined in the premotor and motor component of the response. Premotor times (and RTs) varied systematically with word-likeness: The more extreme categories of high-frequency words and illegal letter strings yielded the fastest responses, whereas the more ambiguous categories produced slower responses. In contrast, motor time, which indexed motor-response execution, was insensitive to word-likeness, but faster for stimuli providing positive evidence about their lexical status (i.e., words and illegal letter strings), compared to those that did not (i.e., pseudowords and letter-substitution pseudowords). These results point to a differentiation in the decisional dynamics modulating premotor and motor time, with motor-response execution being selectively sensitive to the presence vs absence of positive evidence, rather than to the more general dimension of word-likeness. More broadly, the findings highlight a differentiation in the processes underlying memory-based recognition depending on the presence vs absence of positive evidence, particularly with respect to the implementation of the corresponding action.

This research used the progressive demasking paradigm to investigate whether perceptual word identification is facilitated by semantic information. Experiment 1 revealed faster identification for taboo than neutral words. Experiment 2 revealed faster identification for taboo than emotionally-comparable non-taboo words, whereas the difference with respect to neutral words was possibly mitigated by list-wise factors related to list composition. Moreover, the facilitation for taboo words was impervious to habituation. The taboo connotation advantage seemingly originates from the attentional capture triggered by tabooness, a socio-culturally determined semantic feature that, under appropriate contextual conditions, modulates perceptual word identification. Our results suggest that (a) semantic processing is a pervasive component of any task involving word processing, and (b) when semantic information does not hinder the main task, it may influence even the earliest stages of word perceptual identification.

People's decisions may change when made in a foreign language (FL). Research testing this foreign language effect (FLE) has mostly used scenarios where uncertainty is expunged or reduced to a form of risk, whereas real-life decisions are usually characterized by uncertainty around outcome likelihood. In the current work, we aimed to investigate whether the FLE on decision-making extends to uncertain scenarios. Moreover, as it is still unclear what linguistic and psychological factors contribute to the FLE, we tested the effects of participants' FL background, cognitive style and risk-taking attitude on decision processes under certain and uncertain conditions. Overall, we report null effects of language context (native versus foreign language) and problem condition (certain versus uncertain prospects) on participants' choices. In addition, we found that both FL background and decision makers' traits modulated participants' choices in a FL, without emerging into the 'classic' FLE on decision-making. However, the direction of such effects was complex, and not always compatible with previous FLE theories. In light of these results, our study highlights the need to reconceptualize the FLE and its implications on decision-making.

Traditional measures of response times (RTs) capture the summed duration of multiple latent and overt processes, including motor-response execution. The present research assessed the functional independence of the decisional components unfolding before vs after the onset of the muscular activation in the context of a lexical decision task requiring manual button-press responses. Specifically, the lexicality effect (slower latencies for nonwords compared to words) was separately tracked across premotor and motor components of RTs under different regimes of decision bias. Whereas at the premotor level the lexicality effect was modulated by the proportion of word vs nonword trials in the block, with a reversal of the lexicality phenomenon when nonwords occurred in 75% of the trials, motor times (i.e., a chronometric measure of response duration) consistently displayed longer durations for nonword responses, irrespective of bias manipulation. The results point to a partial functional independence between the decisional components involved at the premotor vs motor level, suggesting that the onset of motor behavior may represent the onset of specific decisional processes, rather than the termination or the continuation of computations unfolding in the premotor interval.

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 = 1,046), 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.

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.

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 = 1,046), 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.

We investigate experimentally whether the perceived offensiveness of slurs survives when they are reported, by comparing Italian slurs and insults in base utterances (Y is an S), direct speech (X said: "Y is an S"), mixed quotation (X said that Y is "an S"), and indirect speech (X said that Y is an S). For all strategies, reporting decreases the perceived offensiveness without removing it. For slurs, but not insults, indirect speech is perceived as more offensive than direct speech. Our hypothesis is that, because slurs constitute hate speech, speakers employ quotation marks to signal their dissociation from slur use.

One of the hottest debates in psychology—whether bilingual-monolingual differences exist in cognitive control—is at a stalemate. Here we propose that the stalemate could be broken by shifting the research focus from whether those differences emerge to why they should. We offer an example of this approach by testing the assumption of current theories of language-control associations that adaptive control is involved in bilingualism, specifically language production. Unbalanced Italian-English bilinguals living in the Milan area completed a Stroop task in their L1 and a picture-naming task in their L2. Both tasks involved a manipulation of the proportion of the type of stimuli that are assumed to require control, i.e., incongruent stimuli in the Stroop task (e.g., the word RED written in blue) and pictures with noncognate names in the picture-naming task (e.g., the picture of a horse, whose Italian name, “cavallo,” has a very different pronunciation). Both confirmatory and exploratory analyses showed a clear dissociation between the two tasks, with the Stroop task producing an interactive pattern indicative of adaptive-control involvement and the picture-naming task failing to produce a similar one. These results suggest that adaptive control may not be involved in bilingual language production and, therefore, may not produce bilingual-monolingual differences in cognitive control. It is hoped that this research will inspire a change in the study of language-control associations, pushing future research efforts towards grounding the assumptions for those associations in empirical evidence.

Currently available data show mixed results as to whether the processing of emotional information has the same characteristics in the native (L1) as in the second language (L2) of bilinguals. We conducted a functional magnetic resonance imaging (fMRI) experiment to shed light on the neurocognitive mechanisms underlying bilinguals' emotional processing in L1 and L2 during an emotional interference task (i.e., the Emotional Stroop Task - EST). Our sample comprised proficient Italian-English bilinguals who learned their L2 during childhood mainly in instructional rather than immersive contexts. In spite of no detectable behavioural effects, we found stronger brain activations for L1 versus L2 emotional words in sectors of the posteromedial cortex involved in attention modulation, episodic memory, and affective processing. While fMRI findings are consistent with the hypothesis of a stronger emotional resonance when processing words in a native language, our overall pattern of results points to the different sensitivity of behavioural and hemodynamic responses to emotional information in the two languages of bilingual speakers.

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.

Evidence suggests that decision processes can propagate to motor-response execution. However, the functional characterization of motor decisional components is not yet fully understood. By combining a classic lexical decision experiment with manipulations of speed-accuracy tradeoff (SAT), the present experiment assessed the hypothesis that decisional effects on chronometric measures of motor-response execution are related to online response control. The electromyographic (EMG) signal associated with manual button-press responses was used to dissociate the premotor component (from stimulus onset until the onset of the EMG activity) from the motor component (from EMG onset until the button-press), thus enabling the assessment of decision-related effects in terms of motor-response duration within single-trial reaction times. Other than replicating all the previously reported SAT effects, the experiment revealed hindered control processes when the instructions emphasized speed over accuracy, as indicated by measures of response control such as partial errors, fast errors, and correction likelihood. Nonetheless, the lexicality effect on motor responses, consisting of slower motor times for pseudowords compared to words, was impervious to any SAT modulation. The results suggest that SAT-induced variations in decision and response control policies may not be the prominent determinant of decision-related effects on motor times, highlighting the multiple “cognitive” components that affect peripheral response execution.

This research investigates voice-based categorization of speakers' sexual orientation, the so-called 'auditory gaydar', while considering stimuli length and the type of measures assessing gaydar judgments. In Study 1 (N = 80), heterosexual individuals listened to gay and heterosexual male speakers in short (single word), medium (single sentence), or long (two sentences) recordings. Next, they guess the speakers' sexual orientation on a Kinsey-like and binary choice. Participants were overall inaccurate in recognizing gay speakers when gaydar judgments were provided on a binary choice. Gay speakers were rated as more gay on a Kinsey-like scale than their heterosexual counterparts, but only when short and medium recordings were listened to. Study 2 (N = 149) examined gaydar accuracy for both male and female speakers by using the same procedure. Gaydar judgments were overall inaccurate for gay and lesbian speakers. For male speakers, a difference between the perceived sexual orientation of gay and heterosexual speakers emerged when stimuli were long. For female speakers, such a difference occurred only in the short and medium recording conditions. Study 3 (N = 137) examined gaydar judgments for male and female speakers when stimuli length was manipulated as the number of words progressively presented in a sentence: short (article), medium (article + first word), long (sentence) stimulus. Overall, gaydar judgments were inaccurate. Gay and lesbian (vs. heterosexual) speakers tended to be rated as more gay on the Kinsey-like scale in the medium stimulus condition. These findings suggest that gaydar judgments can be influenced by the type of measure and stimuli.