Word structure tunes electrophysiological and hemodynamic responses in the frontal cortex

As a morphological impoverished language, how does word structure impact Chinese lexical processing in the brain? To address this issue, the current study examined the temporal signatures and localizations in the human brain for morphological priming effect (compound/derivation constitute priming vs. non-morphological priming) and word structure modulation (derivation vs. compound) in light of EEG-fNIRS fusion. Whilst morphological priming effect was manifested in behavioral performance and left prefrontal hemodynamic responses, word structure effect was prominent drawing on behavioral, ERP, and fNIRS data. Chinese derivations elicited greater activation in the frontal cortex and engaged more distributed network than lexicalized compounds. The results were interpreted by the differing connection patterns between constitute morphemes within a given word structure from spreading activation perspective. Together, Chinese word structure effect showed a distinct pattern from the dual-route mechanism in alphabetic languages. Meanwhile, the current study for the first time identified dissociable behavioral and neurophysiological responses of Chinese derivations and coordinate compounds.

Letter transpositions and morphemic boundaries in the second language processing of derived words: An exploratory study of individual differences

Research into nonnative (L2) morphological processing has produced largely conflicting findings. To contribute to the discussions surrounding the contradictory findings in the literature, we examined L2 morphological priming effects along with a transposed-letter (TL) methodology. Critically, we also explored the potential effects of individual differences in the reading networks of L2 speakers using a test battery of reading proficiency. A masked primed lexical decision experiment was carried out in which the same target (e.g., ALLOW) was preceded by a morphological prime (allowable), a TL-within prime (allwoable), an substituted letter (SL)-within prime (allveable), a TL-across prime (alloawble), an SL-across prime (alloimble), or an unrelated prime (believable). The average data yielded morphological priming but no significant TL priming. However, the results of an exploratory analysis of the potential effects of individual differences suggested that individual variability mediated the group-level priming patterns in L2 speakers. TL-within and TL-across priming effects were obtained only when the performance of participants on nonword reading was considered, while the magnitude of the morphological priming effects diminished as the knowledge of vocabulary expanded. The results highlight the importance of considering individual differences while testing L2 populations.

The inflectional morphology representation of individual words in the mental lexicon

Models of complex word recognition can be separated into two wide groups: symbolic and connectionist. Symbolic models presume the existence of an explicit morphological representation of individual words; connectionist models do not and consider morphological effects to be a by-product of interaction between phonological, orthographic and semantic information. This study aimed to test whether there are explicit mental representations of inflected lexical units in the mental lexicon. Accordingly, the method of inflected suffix morphological and semantic priming of nouns in the Serbian language was used. In the morphological priming condition, the prime and the target shared the same inflectional suffix. In Experiment 1 overt priming was used, while in Experiment 2, masked priming. The results showed no significant effects of inflected suffix morphological priming, while significant semantic priming effects were recorded. The results obtained in this research are in line with predictions of the connectionist models.

Morphological processing in nominalizations

A major debate in psycholinguistics concerns the representation of morphological structure in the mental lexicon. We report the results of an auditory primed lexical decision experiment in which we tested whether verbs prime their nominalizations in Dutch. We find morphological priming effects with regular nominalizations (schorsen ‘suspend’ → schorsing ‘suspension’) as well as with irregular nominalizations (schieten ‘shoot’ → schot ‘shot’). On this basis, we claim that, despite the lack of phonological identity between stem and derivation in the case of irregular nominalizations, the morphological relation between the two forms, suffices to evoke a priming effect. However, an alternative explanation, according to which the semantic relation in combination with the phonological overlap accounts for the priming effect, cannot be excluded.

Finding a 'flower' in a 'peanut' is as easy as in a 'garden': towards a lemma-based model of bilingual word recognition

The present study investigates how morphological information is processed and represented in the bilingual lexicon. We employed a masked cross-language morphological priming paradigm to examine morphological decomposition and semantic transparency in bilingual lexical processing. A robust and reliable morphological priming effect was observed for both transparent compounds and opaque compounds, though there was a strong trend for more facilitation in the former than the latter. To account for these results, we propose a lemma-based bilingual model specifying the activation/competition between lemmas during cross-language activation at the morphological level. Our novel findings advance the understanding of interplay between morphology and bilingualism.

Investigating variability in morphological processing with Bayesian distributional models

We investigated the processing of morphologically complex words adopting an approach that goes beyond estimating average effects and allows testing predictions about variability in performance. We tested masked morphological priming effects with English derived (‘printer’) and inflected (‘printed’) forms priming their stems (‘print’) in non-native speakers, a population that is characterized by large variability. We modelled reaction times with a shifted-lognormal distribution using Bayesian distributional models, which allow assessing effects of experimental manipulations on both the mean of the response distribution (‘mu’) and its standard deviation (‘sigma’). Our results show similar effects on mean response times for inflected and derived primes, but a difference between the two on the sigma of the distribution, with inflectional priming increasing response time variability to a significantly larger extent than derivational priming. This is in line with previous research on non-native processing, which shows more variable results across studies for the processing of inflected forms than for derived forms. More generally, our study shows that treating variability in performance as a direct object of investigation can crucially inform models of language processing, by disentangling effects which would otherwise be indistinguishable. We therefore emphasise the importance of looking beyond average performance and testing predictions on other parameters of the distribution rather than just its central tendency.