The neural correlates of grammatical gender decisions in Spanish

A standardized approach to measuring gender transparency in languages

Languages can express grammatical gender through different ortho-phonological regularities present in nouns (e.g., the cues "-o" and "-a" for the masculine and the feminine respectively in Italian, Portuguese, or Spanish). The term "gender transparency" was coined to describe these regularities (Bates et al., 1995). In gendered languages, we can hence distinguish between transparent nouns, i.e., those displaying form regularities; opaque nouns, i.e., those with ambiguous endings; and irregular nouns, i.e., those that display the typical form regularities but are associated with the opposite gender. Following a descriptive analysis of such regularities, languages have been recently classified according to their degree of gender transparency, which seems relevant in regard to gender acquisition and processing. Yet, there are certain inconsistencies in determining which languages are overall transparent and which are opaque. In particular, it is not clear whether some other complex regularities such as derivational suffixes are also "transparent" cues for gender, what really constitutes an "opaque" noun, or which role orthography and morphology have in transparency. Given the existing inconsistencies in classifying languages as transparent or opaque, this work introduces a proposal to assess gender transparency systematically. Our methodology adapts the standardized factors proposed by Audring (2019) to analyse the relative complexity of gender systems. Such factors are adapted to gender transparency on the basis of the literature on gender acquisition and processing. To support the feasibility of such a proposal, the concepts have been instantiated in a quantitative model to obtain for the first time an objective measure of gender transparency using European Portuguese and Dutch as instances of target languages. Our results coincide with the theoretically expected outcome: European Portuguese obtains a high value of gender transparency while Dutch obtains a moderately low one. Future adaptations of this model to the gender systems of other languages could allow the continuum of gender transparency to sustain robust predictions in studies on gender processing and acquisition.

The role of word form in gender processing during lexical access: A theoretical review and novel proposal in language comprehension

In contrast to language production, there are few comprehension models of the representation and use of grammatical gender in long-term memory. To bridge this gap, we conducted a systematic review of empirical studies on the role of gender-form regularities in the recognition of nouns in isolation and within sentences. The results of a final sample of 40 studies suggest that there are two routes for the retrieval of gender during real-time comprehension: a form-based route and a lexical-based route. Our review indicates that the use of these routes depends on the degree of gender transparency of the language and the degree of overtness of the experimental paradigm. To accommodate these findings, we incorporate a dual-route mechanism within a general model of lexical access in comprehension, the AUSTRAL (Activation Using Structurally Tiered Representations and Lemmas) model, and identify directions for future research.

Grammatical Gender in Spoken Word Recognition in School-Age Spanish-English Bilingual Children

This study investigated grammatical gender processing in school-age Spanish-English bilingual children using a visual world paradigm with a 4-picture display where the target noun was heard with a gendered article that was either in a context where all distractor images were the same gender as the target noun (same gender; uninformative) or in a context where all distractor images were the opposite gender than the target noun (different gender; informative). We investigated 32 bilingual children (ages 5;6-8;6) who were exposed to Spanish since infancy and began learning English by school entry. Along with the eye-tracking experiment, all children participated in a standardized language assessment and told narratives in English and Spanish, and parents reported on their child's current Spanish language use. The differential proportion fixations to target (target - averaged distractor fixations) were analyzed in two time regions with linear mixed-effects models (LME). Results show that prior to the target word being spoken, these bilingual children did not use the gendered articles to actively anticipate upcoming nouns. In the subsequent time region (during the noun), it was shown that there are differences in the way they use feminine and masculine articles, with a lack of use of the masculine article and a potential facilitatory use of the feminine article for children who currently use more Spanish than English. This asymmetry in the use of gendered articles in processing is modulated by current Spanish language use and trends with results found for bilingual and second-language learning adults.

The neural substrate of noun morphological inflection: A rapid event-related fMRI study in Italian

The present research investigated the neural correlates of nominal inflection and aimed at disclosing their possible link with the frequency distribution of noun inflectional features: grammatical gender, inflectional suffixes and inflectional classes. The properties of the Italian nominal system were exploited since it allows to explore exhaustively fine-grained phenomena in the inflectional processing. An event-related functional magnetic resonance imaging (fMRI) experiment was carried out where Italian masculine and feminine nouns were visually presented to 50 healthy participants in an overt inflectional task: the generation of the plural from the singular and vice versa. The grammatical gender and the citation form suffix of nouns were manipulated in a factorial design. Functional data showed that inflectional operations for nouns activate an extensive cortical network involving the left inferior and right superior frontal gyri, the left and right middle temporal gyri, the posterior cingulate cortex and the cerebellum. Activations were variably modulated by the distributional features of gender-dependent properties of nouns. Particularly, cortical activity increased during inflectional operations for small and/or scarcely consistent inflectional classes. These findings demonstrate the relevance of specific morphological (inflectional suffixes) and distributional features (size and consistency) shared by groups of words (inflectional classes) in a language, particularly when implementing cognitive operations required for language processing.

The Processing of Grammatical Gender Agreement in Brazilian Portuguese: ERP Evidence in Favor of a Single Route

The present study used event-related potentials to investigate whether the processing of grammatical gender agreement involving gender regular and irregular forms recruit the same or distinct neurocognitive mechanisms and whether different grammatical gender agreement conditions elicit the same or diverse ERP signals. Native speakers of Brazilian Portuguese read sentences containing congruent and incongruent grammatical gender agreement between a determiner and a regular or an irregular form (condition 1) and between a regular or an irregular form and an adjective (condition 2). However, in condition 2, trials with incongruent regular forms elicited more positive ongoing waveforms than trial with incongruent irregular forms. We found a biphasic LAN/P600 effect for gender agreement violation involving regular and irregular forms in both conditions. Our findings suggest that gender agreement between determiner and nouns recruits the same neurocognitive mechanisms regardless of the nouns' form and that, depending on the grammatical class of the words involved in gender agreement, differences in ERP signals can emerge.

Incidental Learning of Gender Agreement in L2

Incidental learning of grammar has been an area of interest for many decades; nevertheless, existing research has primarily focused on artificial or semi-artificial languages. The present study examines the incidental acquisition of the grammar of a natural language by exposing adult speakers of an ungendered L1 (English) to the gender agreement patterns in Russian (a language that was novel to the learners). Both receptive and productive knowledge and the mediating role of working memory (WM) in learning were measured. Speakers of the ungendered language were able to successfully acquire receptive but not productive grammatical knowledge in a new language under incidental exposure. WM was engaged in production but not in a grammaticality judgment task in the incidental learning condition, indicating cognitive effort during knowledge retrieval.

Neural Correlates of Morphological Processing: Evidence from Chinese

Morphological decomposition is an important part of complex word processing. In Chinese, this requires a comprehensive consideration of phonological, orthographic and morphemic information. The left inferior frontal gyrus (L-IFG) has been implicated in this process in alphabetic languages. However, it is unclear whether the neural mechanisms underlying morphological processing in alphabetic languages would be the same in Chinese, a logographic language. To investigate the neural basis of morphological processing in Chinese compound words, an fMRI experiment was conducted using an explicit auditory morphological judgment task. Results showed the L-IFG to be a core area in Chinese morphological processing, consistent with research in alphabetic languages. Additionally, a broad network consisting of the L-MTG, the bilateral STG and the L-FG that taps phonological, orthographic, and semantic information was found to be involved. These results provide evidence that the L-IFG plays an important role in morphological processing even in languages that are typologically different.

How age of acquisition influences brain architecture in bilinguals

In the present study, we explored how Age of Acquisition (AoA) of L2 affected brain structures in bilingual individuals. Thirty-six native English speakers who were bilingual were scanned with high resolution MRI. After MRI signal intensity inhomogeneity correction, we applied both voxel-based morphometry (VBM) and surface-based morphometry (SBM) approaches to the data. VBM analysis was performed using FSL's standard VBM processing pipeline. For the SBM analysis, we utilized a semi-automated sulci delineation procedure, registered the brains to an atlas, and extracted measures of twenty four pre-selected regions of interest. We addressed three questions: (1) Which areas are more susceptible to differences in AoA? (2) How do AoA, proficiency and current level of exposure work together in predicting structural differences in the brain? And (3) What is the direction of the effect of AoA on regional volumetric and surface measures? Both VBM and SBM results suggested that earlier second language exposure was associated with larger volumes in the right parietal cortex. Consistently, SBM showed that the cortical area of the right superior parietal lobule increased as AoA decreased. In contrast, in the right pars orbitalis of the inferior frontal gyrus, AoA, proficiency, and current level of exposure are equally important in accounting for the structural differences. We interpret our results in terms of current theory and research on the effects of L2 learning on brain structures and functions.

The role of the insula in speech and language processing

Lesion and neuroimaging studies indicate that the insula mediates motor aspects of speech production, specifically, articulatory control. Although it has direct connections to Broca's area, the canonical speech production region, the insula is also broadly connected with other speech and language centres, and may play a role in coordinating higher-order cognitive aspects of speech and language production. The extent of the insula's involvement in speech and language processing was assessed using the Activation Likelihood Estimation (ALE) method. Meta-analyses of 42 fMRI studies with healthy adults were performed, comparing insula activation during performance of language (expressive and receptive) and speech (production and perception) tasks. Both tasks activated bilateral anterior insulae. However, speech perception tasks preferentially activated the left dorsal mid-insula, whereas expressive language tasks activated left ventral mid-insula. Results suggest distinct regions of the mid-insula play different roles in speech and language processing.

Sublexical and lexico-syntactic factors in gender access in Spanish

The influence of sublexical and lexico-syntactic factors during the grammatical gender assignment process in Spanish was studied in two experiments using the gender decision task. In Experiment 1, the regularity of the ending of gender-marked nouns (masculine nouns ended in -o and feminine nouns ended in -a) and of nouns with gender-correlated but unmarked word-endings (e.g., -ad) was manipulated. The results showed that regularity affected reaction times and error rates only in the case of gender-marked nouns, suggesting that the mere statistical distribution of a word-ending across genders is not responsible for the regularity effect. In Experiment 2, gender-marked nouns and gender-unmarked nouns were preceded by a masked prime which could be a definite article (which provides information about the gender of the noun) or a possessive pronoun (which does not contain gender information). The presentation of the definite article led to shorter reaction times and less errors only when the word-ending was different from -o or -a. Taken together, these results indicate that gender assignment in Spanish is carried out through different processes depending on the noun ending: gender decisions for gender-marked nouns are based on the gender-to-ending distribution. Meanwhile, gender decisions for unmarked nouns seem to require the retrieval of the corresponding definite grammatical article, regardless of the statistical distribution of the noun ending across genders.

Fronto-parietal dorsal and ventral pathways in the context of different linguistic manipulations

This study investigates structural connectivity between left fronto-parietal brain regions that were identified in a previous fMRI study which used different linguistic manipulation tasks. Diffusion-weighted images were acquired from 20 volunteers. Structural connectivity between brain regions from the fMRI study was computed using probabilistic fiber tracking. For suprasegmental manipulation, left inferior parietal lobule (IPL) and left inferior frontal gyrus (IFG), pars opercularis, were connected by a dorsal pathway via the arcuate fascicle and superior longitudinal fascicle III. For segmental manipulation, left IPL and IFG, pars triangularis, were connected by a ventral pathway via the middle longitudinal fascicle and the extreme capsule. We conclude that the dorsal pathway provides a route for mapping from phonological memory in IPL to the inferior frontal articulatory network while the ventral pathway could facilitate the modulation of phonological units based on lexical-semantic aspects, mediate the complexity of auditory objects and the unification of actor-event schemata.

Clustering the lexicon in the brain: a meta-analysis of the neurofunctional evidence on noun and verb processing

Although it is widely accepted that nouns and verbs are functionally independent linguistic entities, it is less clear whether their processing recruits different brain areas. This issue is particularly relevant for those theories of lexical semantics (and, more in general, of cognition) that suggest the embodiment of abstract concepts, i.e., based strongly on perceptual and motoric representations. This paper presents a formal meta-analysis of the neuroimaging evidence on noun and verb processing in order to address this dichotomy more effectively at the anatomical level. We used a hierarchical clustering algorithm that grouped fMRI/PET activation peaks solely on the basis of spatial proximity. Cluster specificity for grammatical class was then tested on the basis of the noun-verb distribution of the activation peaks included in each cluster. Thirty-two clusters were identified: three were associated with nouns across different tasks (in the right inferior temporal gyrus, the left angular gyrus, and the left inferior parietal gyrus); one with verbs across different tasks (in the posterior part of the right middle temporal gyrus); and three showed verb specificity in some tasks and noun specificity in others (in the left and right inferior frontal gyrus and the left insula). These results do not support the popular tenets that verb processing is predominantly based in the left frontal cortex and noun processing relies specifically on temporal regions; nor do they support the idea that verb lexical-semantic representations are heavily based on embodied motoric information. Our findings suggest instead that the cerebral circuits deputed to noun and verb processing lie in close spatial proximity in a wide network including frontal, parietal, and temporal regions. The data also indicate a predominant-but not exclusive-left lateralization of the network.

Double dissociation between syntactic gender and picture naming processing: a brain stimulation mapping study

Neural foundations of syntactic gender processing remain poorly understood. We used electrostimulation mapping in nine right-handed awake patients during surgery for a glioma within the left hemisphere, to study whether the cortico-subcortical structures involved in naming versus syntactic gender processing are common or distinct. In French, the article determines the grammatical gender. Thus, the patient was asked to perform a picture naming task and to give the appropriate article for each picture, with and without stimulation. Cortical stimulation elicited reproducible syntactic gender disturbances in six patients, in the inferior frontal gyrus (three cases), and in the posterior middle temporal gyrus (three cases). Interestingly, no naming disorders were generated during stimulation of the syntactic sites, while cortical areas inducing naming disturbances never elicited grammatical gender errors when stimulated. Moreover, at the subcortical level, stimulation of the white matter lateral to the caudate nucleus induced gender errors in three patients, with no naming disorders. Using cortico-subcortical electrical mapping in awake patients, we demonstrate for the first time (1) a double dissociation between syntactic gender and naming processing, supporting independent network model rather than serial theory, (2) the involvement of the left inferior frontal gyrus, especially the pars triangularis, and the posterior left middle temporal gyrus in grammatical gender processing, (3) the existence of white matter pathways, likely a sub-part of the left superior longitudinal fasciculus, underlying a large-scale distributed cortico-subcortical circuit which might selectively sub-serve syntactic gender processing, even if interconnected with parallel sub-networks involved in naming (semantic and phonological) processing.

Imaging implicit morphological processing: evidence from Hebrew

Is morphology a discrete and independent element of lexical structure or does it simply reflect a fine-tuning of the system to the statistical correlation that exists among orthographic and semantic properties of words? Hebrew provides a unique opportunity to examine morphological processing in the brain because of its rich morphological system. In an fMRI masked priming experiment, we investigated the neural networks involved in implicit morphological processing in Hebrew. In the lMFG and lIFG, activation was found to be significantly reduced when the primes were morphologically related to the targets. This effect was not influenced by the semantic transparency of the morphological prime, and was not found in the semantic or orthographic condition. Additional morphologically related decrease in activation was found in the lIPL, where activation was significantly modulated by semantic transparency. Our findings regarding implicit morphological processing suggest that morphology is an automatic and distinct aspect of visually processing words. These results also coincide with the behavioral data previously obtained demonstrating the central role of morphological processing in reading Hebrew.

Hebrew brain vs. English brain: language modulates the way it is processed

Is language processing universal? How do the specific properties of each language influence the way it is processed? In this study, we compare the neural correlates of morphological processing in Hebrew--a Semitic language with a rich and systematic morphology, to those revealed in English--an Indo-European language with a linear morphology. Using fMRI, we show that while in the bilingual brain both languages involve a common neural circuitry in processing morphological structure, this activation is significantly modulated by the different aspects of language. Whereas in Hebrew, morphological processing is independent of semantics, in English, morphological activation is clearly modulated by semantic overlap. These findings suggest that the processes involved in reading words are not universal, and therefore impose important constraints on current models of visual word recognition.

Where syntax meets math: right intraparietal sulcus activation in response to grammatical number agreement violations

Previous research has shown that the processing of words referring to actions activated motor areas. Here, we show activation of the right intraparietal sulcus, an area that has been associated with quantity processing, when participants are asked to read pairs of words with number agreement violations as opposed to phrases with gender agreement violations or with no violation. In addition, we show activation in the left premotor and left inferior frontal areas when either gender or number agreement is violated. We argue that number violation automatically activates processes linked to quantity processing which are not directly related to language mechanisms.

Left cytoarchitectonic area 44 supports selection in the mental lexicon during language production

This functional magnetic resonance imaging (fMRI) study investigated the role of Broca’s region for selecting semantic, syntactic, and phonological information during picture naming. According to psycholinguistic theory, selection is reflected in speech latency differences, e.g. during priming. Here, homogenous (priming) blocks in which German picture names had the same semantic category, syntactic gender, or initial phoneme alternated with heterogeneous (non-priming) blocks. Speech latencies revealed a negative priming effect. Speech latencies were used as regressors for the fMRI data in order to tap selection processes. In Broca’s region (BA 44), among others, fMRI data showed repetition priming, which was positive for semantic and syntactic but negative for phonological selection. The different effects in area 44 are discussed in terms of psycholinguistic theory. Overall, the activation pattern is in line with the hypothesis that area 44 generally supports selection processes during noun production at several levels of the mental lexicon.

Syntactic gender processing in the human brain: a review and a model

Despite the increasing number of neuroimaging studies of syntactic gender processing no model is currently available that includes data from visual and auditory language comprehension and language production. This paper provides a systematic review of the neural correlates of syntactic gender processing. Based on anatomical information from cytoarchitectonic probability maps it is argued that the left BA 44 plays a central role for the active use of gender information, e.g., for explicit decisions as well as for subsequent morphological encoding. The left BA 45 is involved in the strategic generation of morphological cues that facilitate gender processing. Model implications for aphasic patients with lesions including or excluding parts of Broca's speech region are discussed.

Neural Correlates of Morphological Processes in Hebrew

Is morphology a discrete and independent element of lexical structure or does it simply reflect a fine tuning of the system to the statistical correlation that exists among the orthographic and semantic properties of words? Imaging studies in English failed to show unequivocal morphological activation that is distinct from semantic or orthographic activation. Cognitive research in Hebrew has revealed that morphological decomposition is an important component of print processing. In Hebrew, morphological relatedness does not necessarily induce a clear semantic relatedness, thus, Hebrew provides a unique opportunity to investigate the neural substrates of morphological processing. In this functional magnetic resonance imaging study, participants were required to perform judgment tasks of morphological relatedness, semantic relatedness, rhyming, and orthographic similarity. Half of the morphologically related words were semantically related and half were semantically unrelated. This design was chosen to induce explicit morphological processing. We identified two locations involved in morphological processing: the left middle frontal gyrus and the left inferior parietal sulcus. Comparing locations of morphological related activation to the locations of semantic and orthographic related activation, we found that the areas neighbored but only partially overlapped. The similarity in activation between the two morphological conditions eliminates the possibility that morphological activation simply results from the semantic properties of the words. These results demonstrate the important role of morphological processing in reading and suggest that morphological analysis is a distinct process of visual word recognition.

Age of acquisition modulates neural activity for both regular and irregular syntactic functions

Studies have found that neural activity is greater for irregular grammatical items than regular items. Findings with monolingual Spanish speakers have revealed a similar effect when making gender decisions for visually presented nouns. The current study extended previous studies by looking at the role of regularity in modulating differences in groups that differ in the age of acquisition of a language. Early and late learners of Spanish matched on measures of language proficiency were asked to make gender decisions to regular (-o for masculine and -a for feminine) and irregular items (which can end in e, l, n, r, s, t and z). Results revealed increased activity in left BA 44 for irregular compared to regular items in separate comparisons for both early and late learners. In addition, within-group comparisons revealed that neural activity for irregulars extended into left BA 47 for late learners and into left BA 6 for early learners. Direct comparisons between groups revealed increased activity in left BA 44/45 for irregular items indicating the need for more extensive syntactic processing in late learners. The results revealed that processing of irregular grammatical gender leads to increased activity in left BA 44 and adjacent areas in the left IFG regardless of when a language is learned. Furthermore, these findings suggest differential recruitment of brain areas associated with grammatical processing in late learners. The results are discussed with regard to a model which considers L2 learning as emerging from the competitive interplay between two languages.

BA 44 in Broca's area supports syntactic gender decisions in language production

The involvement of Broca's area in syntactic gender processing has been shown for metalinguistic decisions in language comprehension and for natural speech production. These studies, however, are not directly comparable owing to the different methods used. The present functional magnetic resonance imaging study investigated gender processing during language production with metalinguistic decisions instead of natural production. Participants saw pictures of real objects and made gender decisions (GEN) about the picture names. Activation was compared with nonlinguistic decisions about geometrical objects (BASE). Broca's area was activated in the contrast GEN > BASE. Using cytoarchitectonic probability maps, the activation was localized at Brodmann's area 44. The data suggest that Brodmann's area 44 in Broca's area is a shared neural correlate for gender processing in production and comprehension.

A dual-route account for access to grammatical gender: evidence from functional MRI

Research investigating the neural correlates of grammatical gender processing has provided contradictory evidence with respect to activation in the left inferior frontal gyrus (IFG). A possible account for these discrepancies is a dual-route model proposing explicit vs implicit access to the gender information. In this event-related fMRI experiment, we investigated this issue by taking into account different processing strategies reported by the subjects. The participants performed two tasks, a gender judgement of German nouns and a non-lexical baseline task (spacing of consonant letter strings). Depending on the reported strategy (silent production of the definite determiner or direct access to the gender information), different patterns of activation in the left IFG were observed. Direct access to gender information yielded activation in the inferior tip of BA 44, whereas the verbalisation strategy elicited activation in the superior portion of BA 44, BA 45/47, and the fronto-median wall. These results speak in favour of a dual-route account for modelling the access to grammatical gender information during language comprehension.

Grammatical gender in the brain: Evidence from an fMRI study on Italian

The grammatical gender of a word is a lexical-syntactic property determining agreement among different sentence parts. Recent fMRI investigations identified the areas involved in the retrieval of grammatical gender near the left Broca's area providing further evidence to confirm the preeminent syntactic role of this area. However, these studies employed categorical designs based on the controversial methodology of the cognitive subtraction of neural activations related to different tasks. In the present study we identified the neural substrates of grammatical gender assignment using an fMRI parametric study. Participants decided the grammatical gender of visually presented Italian words whose gender-to-ending regularity varied. The results showed activation in left and right fronto-temporal areas suggesting an interplay of both hemispheres in the processing of grammatical gender.