Morphological processing without semantics: An ERP study with spoken words

Acquisition of orthographic forms via spoken complex word training

This study used a novel word-training paradigm to examine the integration of spoken word knowledge when learning to read morphologically complex novel words. Australian primary school children including Grades 3-5 were taught the oral form of a set of novel morphologically complex words (e.g., (/vɪbɪŋ/, /vɪbd/, /vɪbz/), with a second set serving as untrained items. Following oral training, participants saw the printed form of the novel word stems for the first time (e.g., vib), embedded in sentences, while their eye movements were monitored. Half of the stems were spelled predictably and half were spelled unpredictably. Reading times were shorter for orally trained stems with predictable than unpredictable spellings and this difference was greater for trained than untrained items. These findings suggest that children were able to form robust orthographic expectations of the embedded morphemic stems during spoken word learning, which may have occurred automatically without any explicit control of the applied mappings, despite still being in the early stages of reading development. Following the sentence reading task, children completed a reading-aloud task where they were exposed to the novel orthographic forms for a second time. The findings are discussed in the context of theories of reading acquisition.

The dynamics of reading complex words: evidence from steady-state visual evoked potentials

The present study used steady-state visual evoked potentials (SSVEPs) to examine the spatio-temporal dynamics of reading morphologically complex words and test the neurophysiological activation pattern elicited by stems and suffixes. Three different types of target words were presented to proficient readers in a delayed naming task: truly suffixed words (e.g., farmer), pseudo-suffixed words (e.g., corner), and non-suffixed words (e.g., cashew). Embedded stems and affixes were flickered at two different frequencies (18.75 Hz and 12.50 Hz, respectively). The stem data revealed an earlier SSVEP peak in the truly suffixed and pseudo-suffixed conditions compared to the non-suffixed condition, thus providing evidence for the form-based activation of embedded stems during reading. The suffix data also showed a dissociation in the SSVEP response between suffixes and non-suffixes with an additional activation boost for truly suffixed words. The observed differences are discussed in the context of current models of complex word recognition.

Brain electrical dynamics in speech segmentation depends upon prior experience with the language

It remains unclear whether the process of speech tracking, which facilitates speech segmentation, reflects top-down mechanisms related to prior linguistic models or stimulus-driven mechanisms, or possibly both. To address this, we recorded electroencephalography (EEG) responses from native and non-native speakers of English that had different prior experience with the English language but heard acoustically identical stimuli. Despite a significant difference in the ability to segment and perceive speech, our EEG results showed that theta-band tracking of the speech envelope did not depend significantly on prior experience with language. However, tracking in the theta-band did show changes across repetitions of the same sentence, suggesting a priming effect. Furthermore, native and non-native speakers showed different phase dynamics at word boundaries, suggesting differences in segmentation mechanisms. Finally, we found that the correlation between higher frequency dynamics reflecting phoneme-level processing and perceptual segmentation of words might depend on prior experience with the spoken language.

The dynamics of morphological processing in developing readers: A cross-linguistic masked priming study

Empirical evidence from masked priming research shows that skilled readers can rapidly identify morphological structure in written language. However, comparatively little is known about how and when this skill is acquired in children. The current work investigated the developmental trajectory of morphological processing in a 2-year longitudinal study involving two large cohorts of German and French primary school children. The masked priming paradigm was used within an experimental design that allowed us to dissociate effects of (a) nonmorphological embedded word activation, (b) morpho-orthographic decomposition, and (c) morpho-semantics. Four priming conditions were used: affixed word (farmer-FARM), affixed nonword (farmity-FARM), nonaffixed nonword (farmald-FARM), and unrelated control (workald-FARM). The results revealed robust embedded word priming effects across both languages. However, morpho-orthographic and morpho-semantic effects were evident only in the French sample. These findings are discussed in the context of a theoretical framework that specifies the distinct roles played by embedded words and affixes, their distinct developmental trajectories, and how the intrinsic linguistic properties of a given language may affect morphological processing.

Observed and Performed Error Signals in Auditory Lexical Decisions

This study investigates the error processing components in the EEG signal of Performers and Observers using an auditory lexical decision task, in which participants heard spoken items and decided for each item if it was a real word or not. Pairs of participants were tested in both the role of the Performer and the Observer. In the literature, an Error Related Negativity (ERN)-Error Positivity (Pe) complex has been identified for performed (ERN-Pe) and observed (oERN-oPe) errors. While these effects have been widely studied for performance errors in speeded decision tasks relying on visual input, relatively little is known about the performance monitoring signatures in observed language processing based on auditory input. In the lexical decision task, native Dutch speakers listened to real Dutch Words, Non-Words, and crucially, long Pseudowords that resembled words until the final syllable and were shown to be error-prone in a pilot study, because they were responded to too soon. We hypothesised that the errors in the task would result in a response locked ERN-Pe pattern both for the Performer and for the Observer. Our hypothesis regarding the ERN was not supported, however a Pe-like effect, as well as a P300 were present. Analyses to disentangle lexical and error processing similarly indicated a P300 for errors, and the results furthermore pointed to differences between responses before and after word offset. The findings are interpreted as marking attention during error processing during auditory word recognition.