Bilingual language production: The neurocognition of language representation and control

“In previous papers (e.g., Abutalebi & Green, 2007, 2008), we reviewed work showing that both cortical and subcortical structures are involved in language control and language switching (see Luk, Green, Abutalebi, & Grady, 2012, for a recent metaanalysis).”

“One model for such a network presented by Abutalebi and Green (2007) describes evidence for a series of connections between prefrontal cortex, anterior cingulate cortex, inferior parietal region, and basal ganglia, all of which are implicated in language production for bilinguals.”

“These studies point to the way two languages are represented and accessed in bilingual minds and inform psycholinguistic theories more broadly (for review see Abutalebi & Green, 2007).”

“There is compelling evidence to suggest that the ACC or components thereof (e.g., Wang, Xue, Chen, Xue, & Donga, 2007; see Abutalebi & Green, 2007, 2008, for reviews) are involved in language-switching tasks, and it has been assumed that this particular structure might also be involved in task…”

“Moreover, as proficiency in the L2 increases, the relative difference in activation between L1 and L2 decreases, again consistent with the idea that there is a decrease in effort (Abutalebi & Green, 2007).”

“…lexical selection that potentially imposes increased processing demands for reducing the activity of candidates in the non-target language (e.g., Abutalebi and Green, 2007; Green, 1998; Kroll, Bobb, Misra and Guo, 2008; Kroll et al., 2006): the less proficient in L2, the more asymmetric the…”

“Finally, in a review of the literature, Abutalebi and Green (2007) argue convincingly for shared neural representations for the two languages of bilinguals, and more importantly in the present context, for the recruitment of general cognitive control mechanisms for the selection, inhibition and production of one langu…”

“At least four of these areas are included in the standard set of regions considered to be part of the executive control system (Abutalebi & Green, 2007).”

“The present results also converge with an emerging body of evidence from both behavioral and neuroimaging studies implicating inhibitory mechanisms in proficient bilingual language processing (e.g., Abutalebi & Green, 2007; Kroll et al., 2008).”

“Earlier studies suggested that AoA is a more important variable (Kim et al., 1997; Mechelli et al., 2004; Weber-Fox & Neville, 1996), whereas later studies point to the distinct role of proficiency (Abutalebi, 2008; Abutalebi et al, 2014; Abutalebi & Green, 2007).”

“Such an interpretation would be supported by the view that neural mechanisms underlying cognitive control demands in bilingual communities with high levels of code switching are different from bilingual communities with practice in avoiding language switching or mixing.(22) The effect of attention could also explain t…”

“Once sufficient proficiency is gained in L2, this extra activity in surrounding areas will disappear (Abutalebi & Green, 2007).”

“Abutalebi and Green (2007) also reviewed fMRI evidence on bilingual language production and claimed that there is a single network mediating the representation of a person’s L1 and L2 and that cortical and subcortical structures generally associated with executive function such as LPFC (left prefrontal cortex) and ACC…”

“Understanding how the brain orchestrates the control of language has been a major focus of neuroimaging research on bilingualism and was central to our original neurocognitive language control model (Abutalebi & Green, 2007).”

“Likewise, as reviewed by Abutalebi and Green (2007), bilinguals with increasing L2 proficiency rely less on these structures underlying a switch from controlled to automatic L2 processing.”

“…in shaping models of bilingual language production and has often been interpreted as the signature of inhibitory control of the nontarget language (Abutalebi & Green, 2007; Costa & Santesteban, 2004; Costa, Santesteban, & Ivanova, 2006; Hernandez & Kohnert, 1999; Jackson, Swainson, Cunnington, &…”

“That bilinguals’ brains are different from monolinguals’ has been documented and discussed in multiple papers (see, e.g., Abutalebi, 2008; Abutalebi & Green, 2007, 2008; Barrett, Ashley, Strait & Kraus, 2013; Chang, 2014; Li, Legault & Litcofsky, 2014).”

“Neural imaging studies also suggest a relationship between task and language-switching (Abutalebi & Green, 2007; Garbin et al., 2010) demonstrating similarities between neural substrates used for both.”

“…networks that support language (e.g., Hernández & Li 2007, Wattendorf et al. 2014), recent studies suggest that language proficiency, rather than the age of acquisition, may be the more important factor in shaping crosslanguage interactions (e.g., Abutalebi & Green 2007, Steinhauer et al. 2009).”

“The usual explanation for the bilingual effect on executive control is that bilinguals need to manage attention to two available systems and therefore recruit the executive control network for this purpose (e.g., Abutalebi & Green, 2007).”

“(Abutalebi and Green 2007; Abutalebi et al. 2000; Marien et al. 2005) because of loss of control over the bilinguals language systems.”

“Prior research indicates that a subcortical structure, the caudate, is responsive to a change in language (e.g., Abutalebi & Green, 2007; Luk, Green, Abutalebi, & Grady, 2012).”

“This literature indicates that there is significant overlap between the left PFC and ACC regions used during perceptual switching and language switching (Abutalebi and Green, 2007; Guo et al., 2011).”

“The lexico-semantic domain has been well studied by means of neuroimaging techniques, and the detailed findings can be found in comprehensive recent overviews (Indefrey 2006; Abutalebi & Green 2007).”

“The contribution of this network has been related to RHM’s conjecture of lexical activation/inhibition, although Abutalebi and Green (2007) noted that the massive involvement of control processes does not fit well with the clear separation made in RHM between the lexicons of L1 and L2 (see also…”

“Although there has been extensive discussion about how different components of cognitive control might be affected by bilingualism (e.g., Abutalebi & Green, 2007; Colzato et al., 2008; Festman, in press; Garbin et al., 2010; Luo, Luk, & Bialystok, 2010), there has been less attention to the issue…”

“In a recent literature review, Abutalebi and Green (2007) underline the crucial role of the left inferior frontal gyrus (IFG), the anterior cingulate cortex (ACC), the left striatum and the left inferior parietal lobe in bilingual language control (involving switching and inhibitory functions).”

“, 2008), the left medial frontal gyrus (Abutalebi and Green, 2007; Wang et al., 2007), and the supplementary motor area (Rodriguez-Fornells et al.”

“The main focus for both these issues is on behavioral results (for nonbehavioral language switching reviews, see Abutalebi & Green, 2007, 2008; Luk, Green, Abutalebi, & Grady, 2012) and how these relate to models of language control.”

“The usual interpretation of the bilingual advantage in executive control traces these effects to one of the three components, namely, enhanced inhibitory control (Abutalebi & Green, 2007); however, little evidence is available to evaluate this claim.”

“…restricted in the first place (for a discussion of this issue see Finkbeiner, Gollan, & Caramazza, 2006b; La Heij, 2005), recent neuroimaging studies provide compelling results for inhibition that may converge with an IC model (e.g., Abutalebi & Green, 2007, 2008; Wang, Kuhl, Chen, & Dong, 2009).”

“The evidence for a bilingual advantage in tasks requiring resolution of conflict, or inhibition of non-relevant information, is consistent with the notion that bilinguals recruit the executive control system in order to manage the simultaneous activation of their two languages (Green, 1998; Abutalebi and Green, 2007;…”

“The neurocognitive and psychological foundation of the model is the emerging functional picture of the multilingual brain, where all linguistic knowledge is interconnected and the different languages of an individual are not functionally separated (Abutalebi & Green, 2007; Paradis, 2004).”

“When there are differences in brain activity in using the two languages, it is likely that they arise from the requirement to engage control mechanisms that regulate the use of the more dominant language and enable the engagement of the weaker language (e.g., Abutalebi & Green, 2007).”

“, the thalamus and the caudate nucleus bilaterally) and the anterior cingulum, all pivotal brain structures for language control in bilingual subjects (19, 39).”

“Given that the neurocognitive mechanisms that underlie bilinguals’ language switching and task switching are partially shared (e.g., Abutalebi & Green, 2007; Weissberger, Gollan, Bondi, Clark, & Wierenga, 2015), the question arises as to whether bilinguals’ qualitatively different…”

“. control such as the pre-Supplementary Motor Area/Anterior Cingulate Cortex (pre-SMA/ACC), prefrontal cortex and the left caudate (Abutalebi and Green, 2007).”

“…in this relationship: The present study cannot differentiate between the effects of language switching (Rodriguez-Fornells et al., 2002), controlled semantic retrieval (Miyashita, 2004; Segalowitz and Hulstijn, 2005) or language conflict management (see Abutalebi and Green, 2007 for a review).”

“For example, Abutalebi and Green (2007) extended the ICmodel to incorporate neurocognitive evidence about bilingual language production.”

“Other posited predictors of L2 learning success include individual differences in cognitive control (Abutalebi and Green 2007), including working memory (Linck et al. 2014; Miyake and Friedman 1998) and conflict monitoring (Abutalebi et al. 2012).”

“Learning and using another language increases interference and places additional demands on the mechanisms that control interference (Green 1986, 1998; Grosjean 1992, 2001; Rodriguez-Fornells et al. 2002, 2005; Abutalebi and Green 2007).”

“The bilingual advantage in executive functions is thought to stem from the fact that managing two languages requires executive resources in the form of selection of the relevant language and inhibition of the language not in use at that moment (Green, 1998; Meuter and Allport, 1999; Rodriguez-Fornells et al., 2006; Ab…”

“However, when bilinguals use one of their languages, the other language remains active and fully accessible, affecting all other representations to which it is connected (Abutalebi & Green, 2007; Boutonnet, Athanasopoulos, & Thierry, 2012; Wu & Thierry, 2010).”

“The cognitive process underlying this ability is often referred to as bilingual language control (bLC; e.g., Green, 1998; Costa and Santesteban, 2004; Crinion et al., 2006; Abutalebi and Green, 2007; Christoffels et al., 2007).”

“control, or does the bilinguals’ improvement of L2-related cognitive control skills further enhance the efficiency of L2 lexical access? Building on Petrides’s (1998) two-level hypothesis on active-controlled (strategic) retrieval and automatic retrieval, Abutalebi and Green (2007) propose that lexical retrieval in lo…”

“The same control mechanisms may be employed to manage the activations of lexical items in different languages and to regulate the activations of different words in one language (Abutalebi and Green, 2007; Rodriguez-Fornells et al., 2006).”

“Work by Abutalebi and colleagues (Abutalebi, Brambati, et al., 2007; Abutalebi & Green, 2007; Abutalebi et al., 2008), however, suggests that brain activity differences during language switching involves control which may reflect inhibition .”

“(Abutalebi and Green, 2007).”

“, use of language A, then of language B) (for a review, see [19,20]).”

“We consider three: (1) age of acquisition of the L2, (2) language proficiency, and (3) nature of the language use in bilingual speakers.”

“…conflict in bilinguals, such as the anterior cingulate cortex (ACC), are the same areas that engage executive function for response selection, task-switching, and inhibition of distractors (Abutalebi & Green, 2007; Rodriguez-Fornells et al., 2005; van Heuven, Schriefers, Dijkstra & Hagoort, 2008).”

“Nevertheless, it should also be specified that subcortical structures do not have per se a role in language representation but rather contribute to language processing with auxiliary functions such as control and attentive functions (Abutalebi & Green, 2007).”

“More recent theoretical work (Abutalebi & Green, 2007; Green & Abutalebi, 2013) supports the relevance of left parietal regions in the maintenance and implementation of task representations during bilingual language production.”

“…in selectiveattention allocation required by switch/non-switch conditions, whether such activation specifically indicates a role for inhibitory control in language selective production remains an open question, and stronger evidence for these claims (e.g., Abutalebi and Green 2007) is needed.”

“E-mail address: brian.gold@uky.edu (B.T. Gold). that have been suggested as a basis for bilingual advantages in executive control (Abutalebi & Green, 2007; Bialystok & Craik, 2010; Green, 1998).”

“Similarly, the medial PFC has been suggested to monitor the language context for bilingual or multilingual speakers (Abutalebi et al., 2013) and to withhold the language not in use (see Abutalebi & Green, 2007).”

“Language control refers to a set of cognitive abilities, which allows bilinguals to utter a word in the intended language, avoiding interference from the nontarget language (Abutalebi and Green 2007, 2008; Green and Abutalebi 2013).”

“The idea is that the executive control mechanism in charge of resolving competition in language related tasks is similar to the control mechanism acting in the domains of perception, attention, or action (Bialystok, 2001; Kan and Thompson-Schill, 2004; Abutalebi and Green, 2007).”

“On the basis of experiments on bilingual speech production, Abutalebi and Green (2007, 2008) propose a model of language control in the multilingual brain whereby a left hemisphere cortico-subcortical loop comprising the anterior cingulate and prefrontal cortices alongside the left caudate nucleus…”

“…question of human cognition: is cognitive representation fixed and static, or is it dynamic and flexible, such that exposure to different languages and cultures alters pre-existing representations (Abutalebi & Green, 2007; Green, 1998; Mechelli, Crinion, Noppeney, et al., 2004; Pavlenko, 1999)?”

“In fact, cognitive control is likely required in bilinguals to switch appropriately between languages, avoiding interference and intrusions from the non-target language (Rodriguez-Fornells et al., 2002a, 2005, 2006; Abutalebi and Green, 2007; Moreno et al., 2008; Ye and Zhou, 2009).”

“001 for all correlations); in addition, the reading self-rating was positively correlated to their QPT score [r(18) = 0.”

“Cognitive control mechanisms are assumed to manage and resolve this competition among distinct language systems [12].”

“…(for review, see Carter et al., 1998, 1999; Botvinick et al., 2001; Braver et al., 2001; Ridderinkhof et al., 2004; Weissman et al., 2005), whereas production would require the intervention of the dlPFC, which is reportedly involved in response selection and inhibition (Abutalebi and Green, 2007).”

“Abutalebi et al. (2007) have shown that the LCN is engaged only when switching into the less dominant language, hence, when more controlled processing is necessary.”

“On the other hand, if the heory and Practice, Bangor University, 37-41 College Road, Bangor, . manner of selection is language-nonspecific, lexical alternatives from both languages are active and compete for selection (e.g., Abutalebi and Green, 2007; Green, 1998; Hermans et al., 1998).”

“This interpretation is consistent with theoretical proposals about language control in normal bilinguals (Abutalebi & Green, 2007) in which the LC and ACC are strongly connected to the prefrontal cortex (McCormick, Ziebell, Nopoulos, Cassell, Andreasen, & Brumm, 2006), and work together with this…”

“Recent data by Abutalebi and Green (2007) suggest that activations vary as a function of proficiency level.”

“…the general view is that a highly overlapping network of regions is recruited by both languages, and that eventual differences depend on the recruitment of additional regions (often prefrontal regions) to compensate for the less automatic control of the second language (Abutalebi & Green, 2007).”

“According to influential inhibitory models (Abutalebi and Green, 2007; Dijkstra and van Heuven, 1998, 2002; Green, 1998; Van Heuven et al., 2008), language selection occurs once lexical candidates are activated in both languages by means of inhibitory mechanisms that reduce the level of activation…”

“…which according to some authors shares (at least partially) functional and neuronal mechanisms with domain-general executive control (EC) processes (e.g. Abutalebi & Green, 2007; Abutalebi et al., 2012; Calabria, Hernández, Branzi, & Costa, 2012; Weissberger, Wierenga, Bondi, & Gollan, 2012).”

“During bilingual language production, these functions may be employed to control which language is in use (Abutalebi and Green, 2007; Green, 1998; Rodriguez-Fornells et al., 2006) or switch from one language to another (Bialystok, 1999, 2001).”

“…and the simultaneous bilinguals in Burgaleta et al., combined with our findings from the less immersed group, suggests that this region may be more relevant to the processing of a less proficient or exercised L2, or utilised during the initial stages of L2 acquisition (Abutalebi and Green 2007).”

“Abutalebi (2008) and Abutalebi and Green (2007) laid out a picture for an inter-connected network in the frontal, temporal, parietal, and striatal regions that work together for monitoring the use of two or more languages and for resolving conflict associated with this process.”

“Although at present few can deny that these two systems interact (for reviews, see Abutalebi & Green, 2007; Hervais-Adelman et al., 2011) we are far from understanding in which way they do so.”