How stereotype threat affects the brain dynamics of creative thinking in female students.

When people are placed in a situation where they are at risk of substantiating a negative stereotype about their social group (a scenario termed stereotype threat), the extra pressure to avoid this outcome can undermine their performance. Substantial and consistent gender disparities in STEM fields leave women vulnerable to stereotype threat, including the stereotype that women are not as good at generating creative and innovative ideas as men. We tested whether female students' creative thinking is affected by a stereotype threat by measuring power in the alpha frequency band (8-12Hz oscillations) that has been associated with better creative thinking outcomes. Counter to expectations that a stereotype threat would reduce alpha power associated with creative thinking, analyses showed increased alpha power following the introduction of the stereotype threat. This outcome suggests that women may have attempted to increase their internal attention during the task in order to disprove the stereotype. Behaviorally, this effort did not lead to changes in creative performance, suggesting that the stereotype threat decoupled alpha power from creative thinking outcomes. These results support a growing school of thought in the neuroscience of creativity literature that the alpha power often seen in conjunction with creative behavior is not necessarily related to the creativity processes themselves, but rather might be part of a larger network modulating the distribution of attentional resources more broadly.

Non-linguistic cognitive measures as predictors of functionally defined developmental language disorder in monolingual and bilingual children.

BACKGROUND & AIMS: Given that standardized language measures alone are inadequate for identifying functionally defined developmental language disorder (fDLD), this study investigated whether non-linguistic cognitive abilities (procedural learning, motor functions, executive attention, processing speed) can increase the prediction accuracy of fDLD in children in linguistically diverse settings. METHODS & PROCEDURES: We examined non-linguistic cognitive abilities in mono- and bilingual school-aged children (ages 8-12) with and without fDLD. Typically developing (TD) children (14 monolinguals, 12 bilinguals) and children with fDLD (28 monolinguals, 12 bilinguals) completed tasks measuring motor functions, procedural learning, executive attention and processing speed. Children were assigned as fDLD based on parental or professional concerns regarding children's daily language functioning. If no concerns were present, children were assigned as TD. Standardized English scores, non-verbal IQ scores and years of maternal education were also obtained. Likelihood ratios were used to examine how well each measure separated the fDLD versus TD groups. A binary logistic regression was used to test whether combined measures enhanced the prediction of identifying fDLD status. OUTCOMES & RESULTS: A combination of linguistic and non-linguistic measures provided the best distinction between fDLD and TD for both mono- and bilingual groups. For monolingual children, the combined measures include English language scores, functional motor abilities and processing speed, whereas for bilinguals, the combined measures include English language scores and procedural learning. CONCLUSIONS & IMPLICATIONS: A combination of non-linguistic and linguistic measures significantly improved the distinction between fDLD and TD for both mono- and bilingual groups. This study supports the possibility of using non-linguistic cognitive measures to identify fDLD in linguistically diverse settings. WHAT THIS PAPER ADDS: What is already known on the subject Given that standardized English language measures may fail to identify functional language disorder, we examined whether supplementing English language measures with non-linguistic cognitive tasks could resolve the problem. Our study is based on the hypothesis that non-linguistic cognitive abilities contribute to language processing and learning. This is further supported by previous findings that children with language disorder exhibit non-linguistic cognitive deficits. What this paper adds to existing knowledge The results indicated that a combination of linguistic and non-linguistic cognitive abilities increased the prediction of functional language disorder in both mono- and bilingual children. What are the potential or actual clinical implications of this work? This study supports the possibility of using non-linguistic cognitive measures to identify the risk of language disorder in linguistically diverse settings.

Are our brains more prescriptive than our mouths? Experience with dialectal variation in syntax differentially impacts ERPs and behavior.

We investigated online auditory comprehension of dialectal variation in English syntax with event-related potential (ERP) analysis of electroencephalographic data. The syntactic variant under investigation was the double modal, comprising two consecutive auxiliary verbs (e.g., might could). This construction appears across subregional dialects of Southern United States English and expresses indirectness or uncertainty. We compared processing of sentences with attested double modals and single modals in two groups of young adult participants: listeners who were either familiar (Southern) or unfamiliar (Unmarked) with double modal constructions. Both Southern and Unmarked listeners engaged rapid error detection (early anterior negativity) and sentence-level reanalysis (P600) in response to attested double modals, relative to single modals. Offline acceptability and intelligibility judgments reflected dialect familiarity, contrary to the ERP data. We interpret these findings in relation to usage-based and socially weighted theories of language processing, which together capture the effects of frequency and standard language ideology.

Neural signatures of inhibitory control in intra-sentential code-switching: Evidence from fMRI.

In this study we examined the neural control mechanisms that are at play when habitual code-switchers read code-switches embedded in a sentence context. The goal was also to understand if and to what extent the putative control network that is engaged during the comprehension of code-switched sentences is modulated by the linguistic regularity of those switches. Towards that goal, we tested two different types of code switches (switches at the noun-phrase boundary and switches at the verb-phrase boundary) that despite being both represented in naturalistic corpora of code switching, show different distributional properties. Results show that areas involved in general cognitive control (e.g., pre-SMA, anterior cingulate cortex) are recruited when processing code-switched sentences, relative to non-code-switched sentences. Additionally, significant activation in the cerebellum when processing sentences containing code-switches at the noun-phrase boundary suggests that habitual code-switchers might engage a wider control network to adapt inhibitory control processes according to task demands. Results are discussed in the context of the current literature on neural models of bilingual language control.

Interactive Alignment and Lexical Triggering of Code-Switching in Bilingual Dialogue.

When bilingual speakers use two languages in the same utterance, this is called code-switching. Previous research indicates that bilinguals' likelihood to code-switch is enhanced when the utterance to be produced (1) contains a word with a similar form across languages (lexical triggering) and (2) is preceded by a code-switched utterance, for example from a dialogue partner (interactive alignment/priming of code-switching). Both factors have mostly been tested on corpus data and have not yet been studied in combination. In two experiments, we therefore investigated the combined effects of interactive alignment and lexical triggering on code-switching. In Experiment 1, Dutch-English bilinguals described pictures to each other in a dialogue game where a confederate's code-switching was manipulated. The participants were free to use either Dutch, English, or a combination of Dutch and English in describing the pictures, so they could voluntarily code-switch or not. The pictures contained a cognate [e.g., roos (rose)], a false friend [e.g., rok (skirt, false friend with rock)], or a control word [e.g., jas (coat)]. Participants code-switched more often when the confederate had just code-switched (indicating interactive alignment). They also code-switched more often when cognates were involved, but only when the confederate had just code-switched. This indicates that lexical triggering is driven by interactive alignment. False friends did not enhance the likelihood of code-switching. Experiment 2 used a similar dialogue game with participants from the same population but focused specifically on how to account for interactive alignment of code-switching. Rather than aligning on their dialogue partner's pragmatic act of code-switching, bilinguals aligned on the language activation from the utterance produced by their dialogue partner. All in all, the results show how co-activation of languages at multiple levels of processing together influence bilinguals' tendency to code-switch. The findings call for a perspective on bilingual language production in which cross-speaker and cross-language processes are combined.

Faces with foreign accents: An event-related potential study of accented sentence comprehension.

Mounting Event-Related Potential (ERP) research testing the neurocognitive processes of foreign- and native-accented speech comprehension shows that listeners process foreign-accented speech in qualitatively and quantitatively different ways from native-accented speech. Previous ERP research has presented listeners with foreign- and native-accented sentences only, devoid of any cues to the speaker's identity. Additional cues about the foreign-accented speaker identity, such as faces, may be useful in aiding listeners' processing, potentially reducing differences between neurocognitive processes associated with foreign-accented and native-accented speech comprehension. This study tested whether providing listeners with extra-linguistic face cues to the speakers' identity affects the ERP correlates of grammatical and semantic processing of foreign-accented and native-accented sentences. Specifically, we presented listeners with face cues to speaker identity followed by native- and foreign-accented sentences that were identical to Grey and Van Hell (2017), who did not provide face cues. To elucidate the effects of face cues, we compared the present study's Face Cue data with the Grey and Van Hell (2017) No Face Cue data. For grammar processing, the results showed a biphasic Nref-P600 for native-accented speech and a P600 for foreign-accented speech in the Face Cue group. In the No Face Cue group, results for grammar processing showed an Nref for native-accented speech and no significant ERP effects for foreign-accented speech. This result indicates that face cues were effective in aiding processing of foreign-accented sentences. For semantic processing, there were robust N400 effects for native-accented speech and delayed N400s for foreign-accented speech in the Face Cue and No Face Cue groups. This pattern indicates that the extra-linguistic face cue to foreign-accented speaker identity did not affect semantic processing. Overall, the results provide neurocognitive evidence that the integration of speaker and face information aids listeners during the processing of foreign-accented speech, particularly for grammatical processing.

Engineering creativity: Prior experience modulates electrophysiological responses to novel metaphors.

Novel metaphorical language use exemplifies human creativity through production and comprehension of meaningful linguistic expressions that may have never been heard before. Available electrophysiological research demonstrates, however, that novel metaphor comprehension is cognitively costly, as it requires integrating information from distantly related concepts. Herein, we investigate if such cognitive cost may be reduced as a factor of prior domain knowledge. To this end, we asked engineering and nonengineering students to read for comprehension literal, novel metaphorical, and anomalous sentences related to engineering or general knowledge, while undergoing EEG recording. Upon reading each sentence, participants were asked to judge whether or not the sentence was original in meaning (novelty judgment) and whether or not it made sense (sensicality judgment). When collapsed across groups, our findings demonstrate a gradual N400 modulation with N400 being maximal in response to anomalous, followed by metaphorical, and literal sentences. Between-group comparisons revealed a mirror effect on the N400 to novel metaphorical sentences, with attenuated N400 in engineers and enhanced N400 in non-engineers. Critically, planned comparisons demonstrated reduced N400 amplitudes to engineering novel metaphors in engineers relative to non-engineers, pointing to an effect of prior knowledge on metaphor processing. This reduction, however, was observed in the absence of a sentence type × knowledge × group interaction. Altogether, our study provides novel evidence suggesting that prior domain knowledge may have a direct impact on creative language comprehension.

Bilingualism and Processing Speed in Typically Developing Children and Children With Developmental Language Disorder.

Purpose The aim of the current study was to investigate whether dual language experience modulates processing speed in typically developing (TD) children and in children with developmental language disorder (DLD). We also examined whether processing speed predicted vocabulary and sentence-level abilities in receptive and expressive modalities. Method We examined processing speed in monolingual and bilingual school-age children (ages 8-12 years) with and without DLD. TD children (35 monolinguals, 24 bilinguals) and children with DLD (17 monolinguals, 10 bilinguals) completed a visual choice reaction time task. The Clinical Evaluation of Language Fundamentals, the Peabody Picture Vocabulary Test, and the Expressive Vocabulary Test were used as language measures. Results The children with DLD exhibited slower response times relative to TD children. Response time was not modified by bilingual experience, neither in children with typical development nor children with DLD. Also, we found that faster processing speed was related to higher language abilities, but this relationship was not significant when socioeconomic status was controlled for. The magnitude of the association did not differ between the monolingual and bilingual groups across the language measures. Conclusions Slower processing speed is related to lower language abilities in children. Processing speed is minimally influenced by dual language experience, at least within this age range. Supplemental Material https://doi.org/10.23641/asha.12210311.

Bilingualism and Attention in Typically Developing Children and Children With Developmental Language Disorder.

Purpose The aim of the current study was to investigate whether dual language experience modulates the efficiency of the 3 attentional networks (alerting, orienting, and executive control) in typically developing (TD) children and in children with developmental language disorder (DLD). Method We examined the attentional networks in monolingual and bilingual school-aged children (ages 8-12 years) with and without DLD. TD children (35 monolinguals, 23 bilinguals) and children with DLD (17 monolinguals, 9 bilinguals) completed the Attention Network Test (Fan et al., 2002; Fan, McCandliss, Fossella, Flombaum, & Posner, 2005). Results Children with DLD exhibited poorer executive control than TD children, but executive control was not modified by bilingual experience. The bilingual group with DLD and both TD groups exhibited an orienting effect, but the monolingual group with DLD did not. No group differences were found for alerting. Conclusions Children with DLD have weak executive control skills. These skills are minimally influenced by dual language experience, at least in this age range. A potential bilingual advantage in orienting may be present in the DLD group.

Bi-Directional Evidence Linking Sentence Production and Comprehension: A Cross-Modality Structural Priming Study.

Natural language involves both speaking and listening. Recent models claim that production and comprehension share aspects of processing and are linked within individuals (Pickering and Garrod, 2004, 2013; MacDonald, 2013; Dell and Chang, 2014). Evidence for this claim has come from studies of cross-modality structural priming, mainly examining processing in the direction of comprehension to production. The current study replicated these comprehension to production findings and developed a novel cross-modal structural priming paradigm from production to comprehension using a temporally sensitive online measure of comprehension, Event-Related Potentials. For Comprehension-to-Production priming, participants first listened to active or passive sentences and then described target pictures using either structure. In Production-to-Comprehension priming, participants first described a picture using either structure and then listened to target passive sentences while EEG was recorded. Comprehension-to-Production priming showed the expected passive sentence priming for syntactic choice, but not response time (RT) or average syllable duration. In Production-to-Comprehension priming, primed, versus unprimed, passive sentences elicited a reduced N400. These effects support the notion that production and comprehension share aspects of processing and are linked within the individual. Moreover, this paradigm can be used for the exploration priming at different linguistic levels as well as the influence of extra-linguistic factors on natural language use.

Neural correlates of word learning in children.

Memory representations of words are thought to undergo changes with consolidation: Episodic memories of novel words are transformed into lexical representations that interact with other words in the mental dictionary. Behavioral studies have shown that this lexical integration process is enhanced when there is more time for consolidation. Neuroimaging studies have further revealed that novel word representations are initially represented in a hippocampally-centered system, whereas left posterior middle temporal cortex activation increases with lexicalization. In this study, we measured behavioral and brain responses to newly-learned words in children. Two groups of Dutch children, aged between 8-10 and 14-16 years, were trained on 30 novel Japanese words depicting novel concepts. Children were tested on word-forms, word-meanings, and the novel words' influence on existing word processing immediately after training, and again after a week. In line with the adult findings, hippocampal involvement decreased with time. Lexical integration, however, was not observed immediately or after a week, neither behaviorally nor neurally. It appears that time alone is not always sufficient for lexical integration to occur. We suggest that other factors (e.g., the novelty of the concepts and familiarity with the language the words are derived from) might also influence the integration process.

The interaction of notional number and morphophonology in subject-verb agreement: A role for working memory.

Research shows that cross-linguistically, subject-verb agreement with complex noun phrases (e.g., The label on the bottles) is influenced by notional number and the presence of homophony in case, gender, or number morphology. Less well-understood is whether notional number and morphophonology interact during speech production, and whether the relative impact of these two factors is influenced by working memory capacity. Using an auditory sentence completion task, we investigated the impact of notional number and morphophonology on agreement with complex subject noun phrases in Dutch. Results revealed main effects of notional number and morphophonology. Critically, there was also an interaction between morphophonology and notional number because participants showed greater notional effects when the determiners were homophonous and morphophonologically ambiguous. Furthermore, participants with higher working memory scores made fewer agreement errors when the subject noun phrase contained homophonous determiners, and this effect was greater when the subject noun phrase was notionally singular. These findings support the hypothesis that cue-based retrieval plays a role in agreement production, and suggests that the ability to correctly assign subject-verb agreement-especially in the presence of homophonous determiners-is modulated by working memory capacity.

Cognitive control and language ability contribute to online reading comprehension: Implications for older adult bilinguals.

Aims: Previous research has indicated that young adults form predictions for the meaning of upcoming words when contexts are highly constrained. This can lead to processing benefits when expectations are met, but also costs, as indicated by a late, frontally distributed and positive event-related potential (ERP), when an unexpected word is encountered. This effect has been associated with the conflict that arises for prediction errors, as well as attempts to suppress a previously formed prediction. However, individual differences have been found for young adult bilingual and older adult monolingual readers, whereby only those who exhibited better language regulation and executive function skill showed this pattern. The goal of the current study was to investigate how these executive functions influence comprehension skill and behavior for elderly bilinguals. Approach: We asked whether older adult monolinguals and bilinguals were capable of generating predictions online, and whether cognitive control and language regulation ability were related to the magnitude of prediction costs. Data and Analysis: Participants (N = 27) read sentences while their electroencephalogram was recorded, and completed a battery of language and cognitive performance tasks. Findings: While older adult monolinguals showed some sensitivity to prediction error, older adult bilinguals produced greater prediction costs, an effect that was significantly correlated with both age and control ability. Originality: This study is the first to show ERP evidence that bilinguals are capable of forming predictions during comprehension in older adulthood. Significance: These results have important implications for the ways in which bilingualism may influence comprehension across the lifespan. While healthy aging has been proposed to lead to declines in executive function these declines may be mitigated for bilinguals, who have a wealth of experience in negotiating language-related conflict.

Cognitive control ability mediates prediction costs in monolinguals and bilinguals.

In this study, we examined the role that cognitive control and language regulation ability play in mediating readers' susceptibility to prediction error costs when reading in the native language (L1) or a second language (L2). Twenty-four English monolinguals (Experiment 1) and 28 Chinese-English bilinguals (Experiment 2) read sentences in English while their EEG was recorded. The sentences varied in the predictability of an upcoming expected word and in whether that prediction was confirmed. Monolinguals showed sensitivity to sentence contexts in which expectations were not met (i.e., when unexpected words were encountered) in the form of a late, frontally-distributed positivity, but for bilinguals this effect was more complex. For both groups, performance on the prediction task was modulated by individual differences on the AX-CPT, a measure of inhibitory control. However, the bilinguals' reading performance in the L2 was affected not only by inhibitory control, but also by their performance on an L1 verbal fluency task that indexed language regulation and production capability, related to their language dominance and immersion context. Bilinguals with better regulation of the L1 generated a larger frontal positivity in response to unexpected words in the L2, an effect that was attenuated by inhibitory control ability. In contrast, bilinguals with lower regulatory ability generated a larger, late negativity, which was also mediated by control. These findings suggest that the ability to regulate the native language when immersed in a second language environment can influence mechanisms underlying the prediction process when reading in the L2. In addition, cognitive control ability, specifically inhibitory control, appears to mediate the difficulty readers incur when predictions are disconfirmed, not only in the native language, but also for proficient bilinguals reading in the L2. We argue that the mechanisms engaged during prediction in the L1 and L2 are fundamentally the same, and that what differs for bilinguals are the additional demands imposed by their language experience and language use.

Bilingualism and Procedural Learning in Typically Developing Children and Children With Language Impairment.

Purpose: The aim of this study was to investigate whether dual language experience affects procedural learning ability in typically developing children and in children with specific language impairment (SLI). Method: We examined procedural learning in monolingual and bilingual school-aged children (ages 8-12 years) with and without SLI. The typically developing children (35 monolinguals, 24 bilinguals) and the children with SLI (17 monolinguals, 10 bilinguals) completed a serial reaction time task. Results: The typically developing monolinguals and bilinguals exhibited equivalent sequential learning effects, but neither group with SLI exhibited learning of sequential patterns on the serial reaction time task. Conclusion: Procedural learning does not appear to be modified by language experience, supporting the notion that it is a child-intrinsic language learning mechanism that is minimally malleable to experience.

Theta-band Oscillations in the Middle Temporal Gyrus Reflect Novel Word Consolidation.

Like many other types of memory formation, novel word learning benefits from an offline consolidation period after the initial encoding phase. A previous EEG study has shown that retrieval of novel words elicited more word-like-induced electrophysiological brain activity in the theta band after consolidation [Bakker, I., Takashima, A., van Hell, J. G., Janzen, G., & McQueen, J. M. Changes in theta and beta oscillations as signatures of novel word consolidation. Journal of Cognitive Neuroscience, 27, 1286-1297, 2015]. This suggests that theta-band oscillations play a role in lexicalization, but it has not been demonstrated that this effect is directly caused by the formation of lexical representations. This study used magnetoencephalography to localize the theta consolidation effect to the left posterior middle temporal gyrus (pMTG), a region known to be involved in lexical storage. Both untrained novel words and words learned immediately before test elicited lower theta power during retrieval than existing words in this region. After a 24-hr consolidation period, the difference between novel and existing words decreased significantly, most strongly in the left pMTG. The magnitude of the decrease after consolidation correlated with an increase in behavioral competition effects between novel words and existing words with similar spelling, reflecting functional integration into the mental lexicon. These results thus provide new evidence that consolidation aids the development of lexical representations mediated by the left pMTG. Theta synchronization may enable lexical access by facilitating the simultaneous activation of distributed semantic, phonological, and orthographic representations that are bound together in the pMTG.

Second language attainment and first language attrition: The case of VOT in immersed Dutch-German late bilinguals.

Speech of late bilinguals has frequently been described in terms of cross-linguistic influence (CLI) from the native language (L1) to the second language (L2), but CLI from the L2 to the L1 has received relatively little attention. This article addresses L2 attainment and L1 attrition in voicing systems through measures of voice onset time (VOT) in two groups of Dutch-German late bilinguals in the Netherlands. One group comprises native speakers of Dutch and the other group comprises native speakers of German, and the two groups further differ in their degree of L2 immersion. The L1-German-L2-Dutch bilinguals (N = 23) are exposed to their L2 at home and outside the home, and the L1-Dutch-L2-German bilinguals (N = 18) are only exposed to their L2 at home. We tested L2 attainment by comparing the bilinguals' L2 to the other bilinguals' L1, and L1 attrition by comparing the bilinguals' L1 to Dutch monolinguals (N = 29) and German monolinguals (N = 27). Our findings indicate that complete L2 immersion may be advantageous in L2 acquisition, but at the same time it may cause L1 phonetic attrition. We discuss how the results match the predictions made by Flege's Speech Learning Model and explore how far bilinguals' success in acquiring L2 VOT and maintaining L1 VOT depends on the immersion context, articulatory constraints and the risk of sounding foreign accented.

How right is left? Handedness modulates neural responses during morphosyntactic processing.

Most neurocognitive models of language processing generally assume population-wide homogeneity in the neural mechanisms used during language comprehension, yet individual differences are known to influence these neural mechanisms. In this study, we focus on handedness as an individual difference hypothesized to affect language comprehension. Left-handers and right-handers with a left-handed blood relative, or familial sinistrals, are hypothesized to process language differently than right-handers with no left-handed relatives (Hancock and Bever, 2013; Ullman, 2004). Yet, left-handers are often excluded from neurocognitive language research, and familial sinistrality in right-handers is often not taken into account. In the current study we used event-related potentials to test morphosyntactic processing in three groups that differed in their handedness profiles: left-handers (LH), right-handers with a left-handed blood relative (RH FS+), and right-handers with no reported left-handed blood relative (RH FS-; both right-handed groups were previously tested by Tanner and Van Hell, 2014). Results indicated that the RH FS- group showed only P600 responses during morphosyntactic processing whereas the LH and RH FS+ groups showed biphasic N400-P600 patterns. N400s in LH and RH FS+ groups are consistent with theories that associate left-handedness (self or familial) with increased reliance on lexical/semantic mechanisms during language processing. Inspection of individual-level results illustrated that variability in RH FS- individuals' morphosyntactic processing was remarkably low: most individuals were P600-dominant. In contrast, LH and RH FS+ individuals showed marked variability in brain responses, which was similar for both groups: half of individuals were N400-dominant and half were P600-dominant. Our findings have implications for neurocognitive models of language that have been largely formulated around data from only right-handers without accounting for familial sinistrality or including left-handers, and moreover highlight that there is systematic - and often ignored - variability in language processing outcomes in neurologically healthy populations.

Switching direction affects switching costs: Behavioral, ERP and time-frequency analyses of intra-sentential codeswitching.

Bilinguals have the unique ability to produce utterances that switch between languages. Most language switching research has focused on isolated, unrelated items, which emphasizes separation of the languages. Fewer studies examined the cognitive and neural mechanisms of switching languages in natural discourse. The present study examined the effect of codeswitching direction on the comprehension of intra-sentential codeswitching in Spanish-English bilinguals, using self-paced reading behavioral measurements (Experiment 1) and electroencephalography (EEG) measurements (Experiment 2), analyzed via both event-related potentials (ERPs) and time-frequency analysis (TFR). Reading times showed a significant switching cost for codeswitched sentences in both codeswitching directions, though switching costs were somewhat higher into the dominant language than into the weaker language. ERPs showed that codeswitched as compared to non-switched words elicited a late positivity, but only when switching from the dominant into the weaker language, not in the reverse direction. TFRs showed complementary and converging results: switches into the weaker language resulted in a power decrease in lower beta band while switches into the dominant language resulted in a power increase in theta band. These multi-method findings provide novel insights into neurocognitive resources engaged in the comprehension of intra-sentential codeswitches related to sentence-level restructuring processes to activate and access the weaker language.

Interaction between episodic and semantic memory networks in the acquisition and consolidation of novel spoken words.

When a novel word is learned, its memory representation is thought to undergo a process of consolidation and integration. In this study, we tested whether the neural representations of novel words change as a function of consolidation by observing brain activation patterns just after learning and again after a delay of one week. Words learned with meanings were remembered better than those learned without meanings. Both episodic (hippocampus-dependent) and semantic (dependent on distributed neocortical areas) memory systems were utilised during recognition of the novel words. The extent to which the two systems were involved changed as a function of time and the amount of associated information, with more involvement of both systems for the meaningful words than for the form-only words after the one-week delay. These results suggest that the reason the meaningful words were remembered better is that their retrieval can benefit more from these two complementary memory systems.