Semantic transparency and masked morphological priming: the case of prefixed words

Spelling principles matter: An ERP study investigating the processing of different types of pseudohomophones

Spelling in any writing system is governed by fundamental principles. We examined the processing of two types of pseudohomophones constructed from words whose spellings are based on different principles - on the traditional principle of writing, requiring memorization of their spelling, and on the morphological principle, allowing the determination of their spelling from another word with the same morpheme (root) to examine the dependence of the occurrence of orthography-phonology conflict on spelling principles. Event-related potentials were recorded from 22 volunteers during silent reading. Pseudohomophones based on the morphological principle increased the N400 amplitude, emphasizing semantic and morphological processing importance. The P600 component showed significant effects for differentiating words and pseudohomophones based on the traditional principle, predominantly indicating the involvement of memory and reanalysis processes. Source reconstruction demonstrates that both pseudohomophones activate the left inferior frontal gyrus. However, pseudohomophones based on the traditional principle additionally activate the right and left postcentral gyrus, indicating the involvement of additional areas in the differentiation process. The earlier differences for stimuli based on the morphological principle indicate access to smaller units (morphemes), whereas stimuli based on the traditional principle require whole word processing. Our findings underscore the significant role of spelling principles in orthographic processing.

The role of morphemic knowledge during novel word learning

This study used a novel word learning paradigm to investigate the role of morphology in the acquisition of complex words, when participants have no prior lexical knowledge of the embedded morphemic constituents. The influence of morphological family size on novel word learning was examined by comparing novel stems (torb) combined with large morphological families (e.g., torbnel, torbilm, torbla, torbiph) as opposed to small morphological families (e.g., torbilm, torbla). In two online experiments, participants learned complex novel words by associating words with pictures. Following training, participants performed a recognition and a spelling task where they were exposed to novel words that either did or did not contain a trained morpheme. As predicted, items consisting of a trained and an untrained constituent were harder to reject but easier to spell than those that did not contain any trained constituents. Moreover, novel words including trained constituents with large morphological families were harder to reject than those including constituents with small morphological families. The findings suggest that participants acquired novel morphemic constituents without prior knowledge of the constituents and point to the important facilitatory role of morphological family size in novel word learning.

LaDEP: A large database of English pseudo-compounds

The Large Database of English Pseudo-compounds (LaDEP) contains nearly 7500 English words which mimic, but do not truly possess, a compound morphemic structure. These pseudo-compounds can be parsed into two free morpheme constituents (e.g., car-pet), but neither constituent functions as a morpheme within the overall word structure. The items were manually coded as pseudo-compounds, further coded for features related to their morphological structure (e.g., presence of multiple affixes, as in ruler-ship), and summarized using common psycholinguistic variables (e.g., length, frequency). This paper also presents an example analysis comparing the lexical decision response times between compound words, pseudo-compound words, and monomorphemic words. Pseudo-compounds and monomorphemic words did not differ in response time, and both groups had slower response times than compound words. This analysis replicates the facilitatory effect of compound constituents during lexical processing, and demonstrates the need to emphasize the pseudo-constituent structure of pseudo-compounds to parse their effects. Further applications of LaDEP include both psycholinguistic studies investigating the nature of human word processing or production and educational or clinical settings evaluating the impact of linguistic features on language learning and impairments. Overall, the items within LaDEP provide a varied and representative sample of the population of English pseudo-compounds which may be used to facilitate further research related to morphological decomposition, lexical access, meaning construction, orthographical influences, and much more.

Sand, Sandpaper, and Sandwiches: Evidence From a Masked Compound Priming Task in L1 and L2 Speakers of English

This study follows the footsteps of Jonathan Grainger and colleagues by investigating compound processing in English monolinguals and Chinese-English bilinguals using the masked primed lexical decision paradigm. First language (L1) and second language (L2) speakers responded to a semantically transparent compound (e.g., snowball-SNOW), a semantically opaque compound (honeymoon-HONEY), and an orthographic control condition (e.g., sandwich-SAND). Results revealed significantly larger L1 priming effects in transparent and opaque compared to the control condition (Experiment 1A), whereas no significant differences across conditions were observed in L2 speakers (Experiment 1B). We argue that L1 populations are sensitive to morphological structure during the early stages of compound processing, whereas L2 speakers, in particular those with lower levels of language proficiency, employ a form-based type of analysis. Findings are interpreted within the framework of recent monolingual and bilingual models of complex word recognition.

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.

The role of syllables and morphemes in silent reading: An eye-tracking study

German skilled readers have been found to engage in morphological and syllable-based processing in visual word recognition. However, the relative reliance on syllables and morphemes in reading multi-syllabic complex words is still unresolved. This study aimed to unveil which of these sublexical units are the preferred units of reading by employing eye-tracking technology. Participants silently read sentences while their eye-movements were recorded. Words were visually marked using colour alternation (Experiment 1) or hyphenation (Experiment 2)-at syllable boundary (e.g., Kir-schen), at morpheme boundary (e.g., Kirsch-en), or within the units themselves (e.g., Ki-rschen). A control condition without disruptions was used as a baseline (e.g., Kirschen). The results of Experiment 1 showed that eye-movements were not modulated by colour alternations. The results of Experiment 2 indicated that hyphens disrupting syllables had a larger inhibitory effect on reading times than hyphens disrupting morphemes, suggesting that eye-movements in German skilled readers are more influenced by syllabic than morphological structure.

Is There an Early Morphological Decomposition during L2 Lexical Access? A Meta-Analysis on the Morphological Priming Effect

A considerable body of experimental data currently exists on the representation and processing of derived words. However, no theoretical account has led to a consensus so far, due in part to inconsistencies in empirical results which show either the presence or the absence of signs of early morphological decomposition during lexical access. In this paper, we present the results of a meta-analysis that sought to examine the robustness of the masked morphological priming effect (MMP) in native and non-native speakers. This effect is indexed by faster responses to targets preceded by morphologically related primes vs. unrelated primes (e.g., fighter-FIGHT < needle-FIGHT), and is perhaps the most widespread effect used to test whether speakers of a given language are sensitive to the morphological components of words at early stages of lexical access. To this end, we selected 10 masked priming lexical decision studies (16 experiments) conducted with native and non-native speakers. Variables such as prime duration and level of L2 proficiency were considered in the analyses to assess their impact on the MMP effect. Results showed significant MMP effects, which were restricted to native speakers. No modulations were found for the prime duration. Results are interpreted in light of prevalent models of complex word processing.

Morphological processing in written word production is based on orthography rather than semantics

Written word production is influenced by central and peripheral processes. Evidence suggests that the activation of morphological units in the lexicon influences the dynamics of handwriting. In this study, we designed two priming experiments to examine the representation level of morphological information in the lexicon during written word production in the French language. In both experiments, target words (e.g., chanteur, "singer") were primed by a derived (e.g., chanter, "to sing"), a pseudo-derived (e.g., chantier, "work site"), or an unrelated (e.g., baleine, "whale") prime. We used the pseudo-derivation condition to disentangle two distinct levels of representation: the sublexical (also known as morpho-orthographic) and the supralexical (morpho-semantic). In Experiment 1 (learning-recall task), we measured the writing latency and writing duration of the target words. In Experiment 2 (word pair copying task), we measured the inter-word duration and writing duration of the target words. We observed morphological priming effects in both experiments: The processing of a derived prime influenced target writing compared to an unrelated prime, but the effect was observed on latencies in Experiment 1 and on target writing duration in Experiment 2. We found similar patterns of priming in the derived and pseudo-derived conditions in both experiments. The findings revealed that morphemes are processed at the morpho-orthographic representation level in written word production. Morphemes serve as grouping units during handwriting, a process that operates independently of their meaning.

From decomposition to distributed theories of morphological processing in reading

The morphological structure of complex words impacts how they are processed during visual word recognition. This impact varies over the course of reading acquisition and for different languages and writing systems. Many theories of morphological processing rely on a decomposition mechanism, in which words are decomposed into explicit representations of their constituent morphemes. In distributed accounts, in contrast, morphological sensitivity arises from the tuning of finer-grained representations to useful statistical regularities in the form-to-meaning mapping, without the need for explicit morpheme representations. In this theoretically guided review, we summarize research into the mechanisms of morphological processing, and discuss findings within the context of decomposition and distributed accounts. Although many findings fit within a decomposition model of morphological processing, we suggest that the full range of results is more naturally explained by a distributed approach, and discuss additional benefits of adopting this perspective.

Coarse or fine? Grain size and morpho-orthographic segmentation in struggling readers

Morpho-orthographic segmentation, rapid parsing of complex written words into their morphological components, is a potential source of difference in word recognition between struggling and typical readers. Although typical readers use morpho-semantic representations and morpho-orthographic segmentation in processing morphologically complex words, struggling readers typically rely on morpho-semantic processes involving coarse-grained processing of whole-word units rather than morpho-orthographic segmentation involving fine-grained letter processing. We tested this limitation in struggling readers, examining reading-ability differences among chronological-age, reading-age, and adult groups in morpho-orthographic segmentation in a primed lexical decision task. We transposed letter order across the morphological boundary of complex-word primes, focusing on disruption in priming effects of morphological and pseudo-orthographic primes that involved only orthographic overlap with target words. Morpho-semantic (coarse-grained) processing in Grade 2 typical readers was indicated by no moderation of priming effects by suffix types and letter transposition. By Grade 6, evidence of emerging fine grained analysis was found in both groups, with clear evidence of both coarse and fine grained analysis in adults. Grade 6 struggling readers showed comparable patterns of coarse and fine grained analysis as Grade 6 typical readers. Although they experienced generalized priming effects, struggling readers did experience response time disruption with transposed primes, indicating that they, like Grade 6 typical readers, adopt fine-grained processing perhaps as a precursor of emerging morpho-orthographic segmentation.

EXPRESS: Are there Task-specific Effects in Morphological Processing? Examining Semantic Transparency Effects in Semantic Categorization and Lexical Decision

Current theories of morphological processing include form-then-meaning accounts, form-with-meaning accounts, and connectionist theories. Form-then meaning accounts argue that the morphological decomposition of complex words is based purely on orthographic structure, while form-with meaning accounts argue that decomposition is influenced by the semantic properties of the stem. Connectionist theories, on the other hand, argue that morphemes are encoded as statistical patterns of occurrences between form and meaning. The weight of evidence from the literature thus far suggests that morphological decomposition is best explained by form-then-meaning accounts. That said, conflicting empirical findings exist, and more importantly, semantic transparency effects in morphological processing have been examined almost exclusively with the lexical decision task, in which participants discriminate between words and nonwords. Consequently, the extent to which observed results reflect the specific demands of the lexical decision task remains unclear. The present study extends previous work by testing if the processing dynamics of early morphological processing are moderated by task requirements. Using the masked morphological priming paradigm, this hypothesis was tested by examining semantic transparency effects for a common set of words across semantic categorization and lexical decision. In both tasks, priming was stronger for transparent (e.g., painter-PAINT) than opaque (e.g., corner-CORN) prime-target pairs; these results speak against form-then-meaning accounts. These findings further inform theories of morphological processing and underscore the importance of examining the interplay between task-general and task-specific mechanisms.

What Language Disorders Reveal About the Mechanisms of Morphological Processing

We addressed an understudied topic in the literature of language disorders, that is, processing of derivational morphology, a domain which requires integration of semantic and syntactic knowledge. Current psycholinguistic literature suggests that word processing involves morpheme recognition, which occurs immediately upon encountering a complex word. Subsequent processes take place in order to interpret the combination of stem and affix. We investigated the abilities of individuals with agrammatic (PPA-G) and logopenic (PPA-L) variants of primary progressive aphasia (PPA) and individuals with stroke-induced agrammatic aphasia (StrAg) to process pseudowords which violate either the syntactic (word class) rules (*reheavy) or the semantic compatibility (argument structure specifications of the base form) rules (*reswim). To this end, we quantified aspects of word knowledge and explored how the distinct deficits of the populations under investigation affect their performance. Thirty brain-damaged individuals and 10 healthy controls participated in a lexical decision task. We hypothesized that the two agrammatic groups (PPA-G and StrAg) would have difficulties detecting syntactic violations, while no difficulties were expected for PPA-L. Accuracy and Reaction Time (RT) patterns indicated: the PPA-L group made fewer errors but yielded slower RTs compared to the two agrammatic groups which did not differ from one another. Accuracy rates suggest that individuals with PPA-L distinguish *reheavy from *reswim, reflecting access to and differential processing of syntactic vs. semantic violations. In contrast, the two agrammatic groups do not distinguish between *reheavy and *reswim. The lack of difference stems from a particularly impaired performance in detecting syntactic violations, as they were equally unsuccessful at detecting *reheavy and *reswim. Reduced grammatical abilities assessed through language measures are a significant predictor for this performance, suggesting that the "hardware" to process syntactic information is impaired. Therefore, they can only judge violations semantically where both *reheavy and *reswim fail to pass as semantically ill-formed. This finding further suggests that impaired grammatical knowledge can affect word level processing as well. Results are in line with the psycholinguistic literature which postulates the existence of various stages in accessing complex pseudowords, highlighting the contribution of syntactic/grammatical knowledge. Further, it points to the worth of studying impaired language performance for informing normal language processes.

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.

Neural correlates of confusability in recognition of morphologically complex Korean words

When people confuse and reject a non-word that is created by switching two adjacent letters from an actual word, is called the transposition confusability effect (TCE). The TCE is known to occur at the very early stages of visual word recognition with such unit exchange as letters or syllables, but little is known about the brain mechanisms of TCE. In this study, we examined the neural correlates of TCE and the effect of a morpheme boundary placement on TCE. We manipulated the placement of a morpheme boundary by exchanging places of two syllables embedded in Korean morphologically complex words made up of lexical morpheme and grammatical morpheme. In the two experimental conditions, the transposition syllable within-boundary condition (TSW) involved exchanging two syllables within the same morpheme, whereas the across-boundary condition (TSA) involved the exchange of syllables across the stem and grammatical morpheme boundary. During fMRI, participants performed the lexical decision task. Behavioral results revealed that the TCE was found in TSW condition, and the morpheme boundary, which is manipulated in TSA, modulated the TCE. In the fMRI results, TCE induced activation in the left inferior parietal lobe (IPL) and intraparietal sulcus (IPS). The IPS activation was specific to a TCE and its strength of activation was associated with task performance. Furthermore, two functional networks were involved in the TCE: the central executive network and the dorsal attention network. Morpheme boundary modulation suppressed the TCE by recruiting the prefrontal and temporal regions, which are the key regions involved in semantic processing. Our findings propose the role of the dorsal visual pathway in syllable position processing and that its interaction with other higher cognitive systems is modulated by the morphological boundary in the early phases of visual word recognition.

Derivational Morphology in Agrammatic Aphasia: A Comparison Between Prefixed and Suffixed Words

Although a relatively large number of studies on acquired language impairments have tested the case of derivational morphology, none of these have specifically investigated whether there are differences in how prefixed and suffixed derived words are impaired. Based on linguistic and psycholinguistic considerations on prefixed and suffixed derived words, differences in how these two types of derivations are processed, and consequently impaired, are predicted. In the present study, we investigated the errors produced in reading aloud simple, prefixed, and suffixed words by three German individuals with agrammatic aphasia (NN, LG, SA). We found that, while NN and LG produced similar numbers of errors with prefixed and suffixed words, SA showed a selective impairment for prefixed words. Furthermore, NN and SA produced more errors specifically involving the affix with prefixed words than with suffixed words. We discuss our findings in terms of relative position of stem and affix in prefixed and suffixed words, as well as in terms of specific properties of prefixes and suffixes.

Pause acceptability indicates word-internal structure in Wubuy

Words in polysynthetic languages, such as the Australian language Wubuy, can be semantically complex and translate into whole phrases in analytic languages such as English. This raises questions about whether such words are like words in English, or whether they are more like phrases. In the following, we examine Wubuy speakers' knowledge of word-internal morphological complexity in a word-preference task, in which we test the acceptability of complex words into which artificial pauses have been embedded at a range of morphological junctures. The results show that participants prefer unmodified words and words with pauses inserted at semantically transparent morphological junctures over words with pauses at other junctures. There is no preference for unmodified words over words with pauses at transparent junctures. These results suggest that speakers have access to some word-internal morphological information, and that complex words may share characteristics of both words and phrases in, for instance, English.

Opacity, Transparency, and Morphological Priming: A Study of Prefixed Verbs in Dutch

A basic question for the study of the mental lexicon is whether there are morphological representations and processes that are independent of phonology and semantics. According to a prominent tradition, morphological relatedness requires semantic transparency: semantically transparent words are related in meaning to their stems, while semantically opaque words are not. This study examines the question of morphological relatedness using intra-modal auditory priming by Dutch prefixed verbs. The key conditions involve semantically transparent prefixed primes (e.g., aanbieden 'offer', with the stem bieden, also 'offer') and opaque primes (e.g., verbieden 'forbid'). Results show robust facilitation for both transparent and opaque pairs; phonological (Experiment 1) and semantic (Experiment 2) controls rule out the possibility that these other types of relatedness are responsible for the observed priming effects. The finding of facilitation with opaque primes suggests that morphological processing is independent of semantic and phonological representations. Accordingly, the results are incompatible with theories that make semantic overlap a necessary condition for relatedness, and favor theories in which words may be related in ways that do not require shared meaning. The general discussion considers several specific proposals along these lines, and compares and contrasts questions about morphological relatedness of the type found here with the different but related question of whether there is morphological decomposition of complex forms or not.

Prefix Stripping Re-Re-Revisited: MEG Investigations of Morphological Decomposition and Recomposition

We revisit a long-standing question in the psycholinguistic and neurolinguistic literature on comprehending morphologically complex words: are prefixes and suffixes processed using the same cognitive mechanisms? Recent work using Magnetoencephalography (MEG) to uncover the dynamic temporal and spatial responses evoked by visually presented complex suffixed single words provide us with a comprehensive picture of morphological processing in the brain, from early, form-based decomposition, through lexical access, grammatically constrained recomposition, and semantic interpretation. In the present study, we find that MEG responses to prefixed words reveal interesting early differences in the lateralization of the form-based decomposition response compared to the effects reported in the literature for suffixed words, but a very similar post-decomposition profile. These results not only address a question stretching back to the earliest days of modern psycholinguistics, but also add critical support and nuance to our much newer emerging understanding of spatial organization and temporal dynamics of morphological processing in the human brain.

Embedded stems as a bootstrapping mechanism for morphological parsing during reading development

The aim of the current research was to test the hypothesis that the activation of embedded words (e.g., the farm in farmhouse) is the starting point for the development of an abstract morphological parsing system in children's reading. To test this hypothesis, we examined the developmental trajectory of compound priming effects in third- and fifth-grade primary school children, high school students, and adults. Both children and adults participated in a masked priming lexical decision study comparing transparent compound (farmhouse-farm), opaque compound (butterfly-butter), and noncompound (sandwich-sand) word priming effects measured relative to an unrelated control. The results showed significant and equal priming effects in the two compound conditions but not in the noncompound priming condition. This robust pattern was clearly and unequivocally observed across all groups of participants. Our data suggest that even the youngest readers have already acquired the ability to rapidly and automatically identify embedded stems and are sensitive to the overall structure of compound words (full decomposition). We conclude that the activation of embedded stems provides a critical starting point in children's use of morphological information when learning to read.

Statistical models of morphology predict eye-tracking measures during visual word recognition

We studied how statistical models of morphology that are built on different kinds of representational units, i.e., models emphasizing either holistic units or decomposition, perform in predicting human word recognition. More specifically, we studied the predictive power of such models at early vs. late stages of word recognition by using eye-tracking during two tasks. The tasks included a standard lexical decision task and a word recognition task that assumedly places less emphasis on postlexical reanalysis and decision processes. The lexical decision results showed good performance of Morfessor models based on the Minimum Description Length optimization principle. Models which segment words at some morpheme boundaries and keep other boundaries unsegmented performed well both at early and late stages of word recognition, supporting dual- or multiple-route cognitive models of morphological processing. Statistical models based on full forms fared better in late than early measures. The results of the second, multi-word recognition task showed that early and late stages of processing often involve accessing morphological constituents, with the exception of short complex words. Late stages of word recognition additionally involve predicting upcoming morphemes on the basis of previous ones in multimorphemic words. The statistical models based fully on whole words did not fare well in this task. Thus, we assume that the good performance of such models in global measures such as gaze durations or reaction times in lexical decision largely stems from postlexical reanalysis or decision processes. This finding highlights the importance of considering task demands in the study of morphological processing.

A Word on Words in Words: How Do Embedded Words Affect Reading?

A surprisingly small portion of reading research has been dedicated to investigating how the visual word recognition process is influenced by embedded words (e.g., 'arm' in 'charm'), and no research has yet investigated embedded words in a natural reading setting. Covering this issue, the present work reports analyses of eye-tracking data from the GECO bilingual book reading corpus. Word viewing times were analyzed as a function of the number, frequency and proportional length of embedded words. We anticipated two scenarios: embedded words would either facilitate processing due to increased word-letter feedback, or inhibit processing due to increased lexical competition. A main facilitatory effect of embedded words on the recognition process was established, with an increasing number of embedded words resulting in shorter word viewing times and fewer fixations. This pattern was depicted by readers of Dutch as well as readers of English. Long, high-frequency embedded words formed an exception however, as these led to inhibition (Dutch participants) or a null-effect (English participants). The present results indicate that both scenarios outlined above are at play, but with a theoretical constraint on the role of word-to-word inhibitory connections. Specifically, such connections may predominantly exist among words of similar length. Hence, embedded words generally facilitate processing through word-letter feedback, but this facilitatory effect is countered by word-to-word inhibition if the embedded word's length approximates that of its superset.

Morphological representations are extrapolated from morpho-syntactic rules

The field of psycho- and neuro-linguistics has long-debated the decompositional model of visual word processing: Are written words processed via the visual forms of stem and affix morphemes, or as complex wholes? Although many have now settled upon a decompositional view, it is unclear what heuristic the brain uses to generate these visual morpheme-forms in the first place. Here we conduct a magneto-encephalography study to test two hypotheses for how this may be done: i) the brain encodes representations of the morphemes that follow the morpho-syntactic rules governing constituents: A stem morpheme will be represented if the word obeys the grammatical behaviour associated with its suffix; ii) the brain only encodes stem morphemes that occur with multiple suffixes or as words in isolation. Our results indicate that words with morpho-syntactic wellformedness as stem-suffix combinations are decomposed by the system, thus supporting the former hypothesis. This suggests that knowledge of morpho-syntactic rules can be used to form morphological representations of written words, in absence of independent experience with all of their constituent morphemes. Possible mechanisms supporting this computation are discussed.

Taking the Book from the Bookshelf: Masked Constituent Priming Effects from Compound Words and Nonwords

Recent evidence from visual word recognition points to the important role of embedded words, suggesting that embedded words are activated independently of whether they are accompanied by an affix or a non-affix. The goal of the present research was to more closely examine the mechanisms involved in embedded word activation, particularly with respect to the “edge-alignedness” of the embedded word. We conducted two experiments that used masked priming in combination with lexical decision. In Experiment 1, monomorphemic target words were either preceded by a compound word prime (e.g., textbook-BOOK/textbook-TEXT), a compound-nonword prime (e.g., pilebook-BOOK/textpile-TEXT), a non-compound nonword prime (e.g., pimebook-BOOK/textpime-TEXT) or an unrelated prime (e.g., textjail-BOOK/jailbook-TEXT). The results revealed significant priming effects, not only in the compound word and compound-nonword conditions, but also in the non-compound nonword condition, suggesting that embedded words (e.g., book) were activated independently of whether they occurred in combination with a real morpheme (e.g., pilebook) or a non-morphemic constituent (e.g., pimebook). Priming in the compound word condition was greater than in the two nonword conditions, indicating that participants benefited from the whole-word representation of real compound words. Constituent priming occurred independently of whether the target word was the first or the second embedded constituent of the prime (e.g., textbook-BOOK vs. textbook-TEXT). In Experiment 2, significant priming effects were found for edge-aligned embedded constituents (e.g., pimebook-BOOK), but not for mid-embedded (e.g., pibookme-BOOK) or the outer-embedded constituents (e.g., bopimeok-BOOK), suggesting that edge-alignedness is a key factor determining the activation of embedded words.

Do 'blacheap' and 'subcheap' both prime 'cheap'? An investigation of morphemic status and position in early visual word processing

Much research suggests that words comprising more than one morpheme are decomposed into morphemes in the early stages of visual word recognition. In the present masked primed lexical decision study, we investigated whether or not decomposition occurs for both prefixed and suffixed nonwords and for nonwords which comprise a stem and a non-morphemic ending. Prime-target relatedness was manipulated in three ways: (1) primes shared a semantically transparent morphological relationship with the target (e.g., subcheap-CHEAP, cheapize-CHEAP); (2) primes comprised targets and non-affixal letter strings (e.g., blacheap-CHEAP, cheapstry-CHEAP); and (3) primes were real, complex words unrelated to the target (e.g., miscall-CHEAP, idealism-CHEAP). Both affixed and non-affixed nonwords significantly facilitated the recognition of their stem targets, suggesting that embedded stems are activated independently of whether they are accompanied by a real affix or a non-affix. There was no difference in priming between stems being embedded in initial and final string positions, indicating that embedded stem activation is position-independent. Finally, more priming was observed in the semantically interpretable affixed condition than in the non-affixed condition, which points to a semantic licensing mechanism during complex novel word processing.

Transposed-Letter Priming Across Inflectional Morpheme Boundaries

This study reports findings from two experiments testing whether a transposed-letter (TL) priming effect can be obtained when the transposition occurs across morphological boundaries. Previous studies have primarily tested derivationally complex words or compound words, but have not examined a more rule-based and productive morphological structure, i.e., inflectionally complex words, using masked priming. Experiment 1 tested TL priming with nonword primes and inflected targets (FOCUSING). Nonword primes were formed by transposing letters either within the root morpheme (fcousing) or across two morphemes (focuisng). Experiment 2 used the same nonword primes, but had the root words as targets (FOCUS). Both experiments showed similar TL priming effects for within-morpheme and across-boundary positions, indicating that morphological decomposition takes place only after letter positions in a word have been assigned. This finding provides additional evidence to previous research testing derived and compound words showing TL priming regardless of the position of transposition.

The Salience of Complex Words and Their Parts: Which Comes First?

This paper deals with the impact of the salience of complex words and their constituent parts on lexical access. While almost 40 years of psycholinguistic studies have focused on the relevance of morphological structure for word recognition, little attention has been devoted to the relationship between the word as a whole unit and its constituent morphemes. Depending on the theoretical approach adopted, complex words have been seen either in the light of their paradigmatic environment (i.e., from a paradigmatic view), or in terms of their internal structure (i.e., from a syntagmatic view). These two competing views have strongly determined the choice of experimental factors manipulated in studies on morphological processing (mainly different lexical frequencies, word/non-word structure, and morphological family size). Moreover, work on various kinds of more or less segmentable items (from genuinely morphologically complex words like hunter to words exhibiting only a surface morphological structure like corner and irregular forms like thieves) has given rise to two competing hypotheses on the cognitive role of morphology. The first hypothesis claims that morphology organizes whole words into morphological families and series, while the second sets morphology at a pre-lexical level, with morphemes standing as access units to the mental lexicon. The present paper examines more deeply the notion of morphological salience and its implications for theories and models of morphological processing.

Not Everybody Sees the Ness in the Darkness: Individual Differences in Masked Suffix Priming

The present study explores the role of individual differences in polymorphemic word recognition. Participants completed a masked priming lexical decision experiment on suffixed words in which targets could be preceded by suffix-related words (words sharing the same suffix) or by affixed primes with a different suffix. Participants also completed a monomorphemic word lexical decision and were divided in two groups (fast and slow readers) according to their performance in this task. When the suffix priming data were analyzed taking into consideration participants' reading speed as a proxy for their greater reliance on orthography or on semantics, a significant interaction between reading speed and the magnitude of the masked suffix priming effects emerged. Only slow participants showed significant priming effects, whereas faster participants showed negligible masked suffix priming effects. These results demonstrate that different reading profiles modulate the access to morphological information in a qualitatively different manner and that individual differences in reading determine the manner in which polymorphemic words are processed.

Do Morphemes Matter when Reading Compound Words with Transposed Letters? Evidence from Eye-Tracking and Event-Related Potentials

The current study investigates the online processing consequences of encountering compound words with transposed letters (TLs), to determine if TLs that cross morpheme boundaries are more disruptive to reading than those within a single morpheme, as would be predicted by accounts of obligatory morpho-orthopgrahic decomposition. Two measures of online processing, eye movements and event-related potentials (ERPs), were collected in separate experiments. Participants read sentences containing correctly spelled compound words (cupcake), or compounds with TLs occurring either across morpheme boundaries (cucpake) or within one morpheme (cupacke). Results showed that between- and within-morpheme transpositions produced equal processing costs in both measures, in the form of longer reading times (Experiment 1) and a late posterior positivity (Experiment 2) that did not differ between conditions. Findings converge to suggest that within- and between-morpheme TLs are equally disruptive to recognition, providing evidence against obligatory morpho-orthographic processing and in favor of whole-word access of English compound words during sentence reading.

Spatiotemporal Dynamics of Morphological Processing in Visual Word Recognition

The spatiotemporal dynamics of morphological, orthographic, and semantic processing were investigated in a primed lexical decision task in French using magnetoencephalography (MEG). The goal was to investigate orthographic and semantic contributions to morphological priming and compare these effects with pure orthographic and semantic priming. The time course of these effects was analyzed in anatomically defined ROIs that were selected according to previous MEG and fMRI findings. The results showed that morphological processing was not localized in one specific area but distributed over a vast network that involved left inferior temporal gyrus, left superior temporal gyrus, left inferior frontal gyrus, and left orbitofrontal gyrus. Second, all morphological effects were specific, that is, in none of the ROIs could morphology effects be explained by pure orthographic or pure semantic overlap. Third, the ventral route was sensitive to both the orthographic and semantic “part” of the morphological priming effect in the M350 time window. Fourth, the earliest effects of morphology occurred in left superior temporal gyrus around 250 msec and reflected the semantic contribution to morphological facilitation. Together then, the present results show that morphological processing is not just an emergent property of processing form or meaning and that semantic contributions to morphological facilitation can occur as early as 250 msec in the left superior temporal gyrus.

Masked Morphological Priming in German-Speaking Adults and Children: Evidence from Response Time Distributions

In this study, we looked at masked morphological priming effects in German children and adults beyond mean response times by taking into account response time distributions. We conducted an experiment comparing suffixed word primes (kleidchen-KLEID), suffixed nonword primes (kleidtum-KLEID), nonsuffixed nonword primes (kleidekt-KLEID), and unrelated controls (träumerei-KLEID). The pattern of priming in adults showed facilitation from suffixed words, suffixed nonwords, and nonsuffixed nonwords relative to unrelated controls, and from both suffixed conditions relative to nonsuffixed nonwords, thus providing evidence for morpho-orthographic and embedded stem priming. Children also showed facilitation from real suffixed words, suffixed nonwords, and nonsuffixed nonwords compared to unrelated words, but no difference between the suffixed and nonsuffixed conditions, thus suggesting that German elementary school children do not make use of morpho-orthographic segmentation. Interestingly, for all priming effects, a shift of the response time distribution was observed. Consequences for theories of morphological processing are discussed.

Morphological Decomposition in Reading Hebrew Homographs

The present work investigates whether and how morphological decomposition processes bias the reading of Hebrew heterophonic homographs, i.e., unique orthographic patterns that are associated with two separate phonological, semantic entities depicted by means of two morphological structures (linear and nonlinear). In order to reveal the nature of morphological processes involved in the reading of Hebrew homographs, we tested 146 university students with three computerized experiments, each experiment focusing on a different level of processing. Participants were divided into three experimental groups given that the three experiments used the same stimulus lists. Evidence obtained from the analysis of the participants' processing time and processing accuracy points to a propensity to process heterophonic homographs by default as morpho-syntactically simple rather than complex words. Findings are discussed with reference to assumptions made by Dual-Route models regarding the importance of morphological knowledge in fast and accurate access of written words' representations which mediate the retrieval of their meanings with direct reference to the context in which they occur.

Morphological Decomposition in Japanese De-adjectival Nominals: Masked and Overt Priming Evidence

Whether morpheme-based processing extends to relatively unproductive derived words remains a matter of debate. Although whole-word storage and access has been proposed for some derived words, such as Japanese de-adjectival nominals with the unproductive (-mi) suffix (e.g., Hagiwara et al. in Language 75:739-763, 1999), Clahsen and Ikemoto (Ment Lex 7:147-182, 2012) found masked priming from de-adjectival nominals with productive (-sa) and unproductive (-mi) suffixes to their adjectivally-inflected base morpheme. Using masked and unmasked priming, we examine whether adjectivally-inflected base morpheme primes facilitate the processing of Japanese de-adjectival nominal targets with a productive or unproductive affix, including an orthographic-overlap condition and semantic relatedness measure that Clahsen and Ikemoto (2012) did not include. Our results replicate and extend Clahsen and Ikemoto (2012), revealing significant, statistically-equivalent morphological priming effects for -sa and -mi affixed targets, independent of orthographic and semantic relatednesss, suggesting that the processing of derived words with the unproductive -mi affix makes recourse to morpheme-level representations.

Evidence from neglect dyslexia for morphological decomposition at the early stages of orthographic-visual analysis

This study examined whether and how the morphological structure of written words affects reading in word-based neglect dyslexia (neglexia), and what can be learned about morphological decomposition in reading from the effect of morphology on neglexia. The oral reading of 7 Hebrew-speaking participants with acquired neglexia at the word level-6 with left neglexia and 1 with right neglexia-was evaluated. The main finding was that the morphological role of the letters on the neglected side of the word affected neglect errors: When an affix appeared on the neglected side, it was neglected significantly more often than when the neglected side was part of the root; root letters on the neglected side were never omitted, whereas affixes were. Perceptual effects of length and final letter form were found for words with an affix on the neglected side, but not for words in which a root letter appeared in the neglected side. Semantic and lexical factors did not affect the participants' reading and error pattern, and neglect errors did not preserve the morpho-lexical characteristics of the target words. These findings indicate that an early morphological decomposition of words to their root and affixes occurs before access to the lexicon and to semantics, at the orthographic-visual analysis stage, and that the effects did not result from lexical feedback. The same effects of morphological structure on reading were manifested by the participants with left- and right-sided neglexia. Since neglexia is a deficit at the orthographic-visual analysis level, the effect of morphology on reading patterns in neglexia further supports that morphological decomposition occurs in the orthographic-visual analysis stage, prelexically, and that the search for the three letters of the root in Hebrew is a trigger for attention shift in neglexia.

Insights from letter position dyslexia on morphological decomposition in reading

We explored morphological decomposition in reading, the locus in the reading process in which it takes place and its nature, comparing different types of morphemes. We assessed these questions through the analysis of letter position errors in readers with letter position dyslexia (LPD). LPD is a selective impairment to letter position encoding in the early stage of word reading, which results in letter migrations (such as reading "cloud" for "could"). We used the fact that migrations in LPD occur mainly in word-interior letters, whereas exterior letters rarely migrate. The rationale was that if morphological decomposition occurs prior to letter position encoding and strips off affixes, word-interior letters adjacent to an affix (e.g., signs-signs) would become exterior following affix-stripping and hence exhibit fewer migrations. We tested 11 Hebrew readers with developmental LPD and 1 with acquired LPD in 6 experiments of reading aloud, lexical decision, and comprehension, at the single word and sentence levels (compared with 25 age-matched control participants). The LPD participants read a total of 12,496 migratable words. We examined migrations next to inflectional, derivational, or bound function morphemes compared with migrations of exterior letters. The results were that root letters adjacent to inflectional and derivational morphemes were treated like middle letters, and migrated frequently, whereas root letters adjacent to bound function morphemes patterned with exterior letters, and almost never migrated. Given that LPD is a pre-lexical deficit, these results indicate that morphological decomposition takes place in an early, pre-lexical stage. The finding that morphologically complex nonwords showed the same patterns indicates that this decomposition is structurally, rather than lexically, driven. We suggest that letter position encoding takes place before morphological analysis, but in some cases, as with bound function morphemes, the complex word is re-analyzed as two separate words. In this reanalysis, letter positions in each constituent word are encoded separately, and hence the exterior letters of the root are treated as exterior and do not migrate.

Effects of reading proficiency on embedded stem priming in primary school children

Prior evidence from masked morphological priming has revealed conflicting findings regarding the acquisition of morpho-orthographic segmentation mechanisms in developing readers. Here, we examined changes in masked morphological priming across grade within a large sample of French primary school children (n = 191, Grades 2-5) and how these effects are modulated by individual differences in reading proficiency, spelling proficiency, and morphological awareness. Target words were preceded by either (a) a suffixed word prime (e.g., tristesse-TRISTE), (b) a suffixed nonword prime (e.g., tristerie-TRISTE), (c) a non-suffixed nonword prime (e.g., tristald-TRISTE), or (d) an unrelated prime (e.g., direction-TRISTE) using very short prime durations (50 ms). Moreover, a frequency manipulation was included for suffixes and non-suffixes. The results revealed robust suffixed word priming across all children independent of grade and proficiency. On the other hand, priming in the suffixed and non-suffixed nonword conditions was modulated by reading proficiency, with high-proficiency children showing facilitation and low-proficiency children showing inhibition. The effects of suffix and non-suffix frequency were modulated by grade, with decreasing effects as grade increased. None of the observed priming effects were modulated by grade, spelling proficiency, or morphological awareness. The results suggest that reading proficiency is an important predictor for embedded stem activation mechanisms in primary school children, which we discuss in the context of recent theories of morphological processing.

Differential recall of derived and inflected word forms in working memory: examining the role of morphological information in simple and complex working memory tasks

Working memory (WM) has been described as an interface between cognition and action, or a system for access to a limited amount of information needed in complex cognition. Access to morphological information is needed for comprehending and producing sentences. The present study probed WM for morphologically complex word forms in Finnish, a morphologically rich language. We studied monomorphemic (boy), inflected (boy+'s), and derived (boy+hood) words in three tasks. Simple span, immediate serial recall of words, in Experiment 1, is assumed to mainly rely on information in the focus of attention. Sentence span, a dual task combining sentence reading with recall of the last word (Experiment 2) or of a word not included in the sentence (Experiment 3) is assumed to involve establishment of a search set in long-term memory for fast activation into the focus of attention. Recall was best for monomorphemic and worst for inflected word forms with performance on derived words in between. However, there was an interaction between word type and experiment, suggesting that complex span is more sensitive to morphological complexity in derivations than simple span. This was explored in a within-subjects Experiment 4 combining all three tasks. An interaction between morphological complexity and task was replicated. Both inflected and derived forms increased load in WM. In simple span, recall of inflectional forms resulted in form errors. Complex span tasks were more sensitive to morphological load in derived words, possibly resulting from interference from morphological neighbors in the mental lexicon. The results are best understood as involving competition among inflectional forms when binding words from input into an output structure, and competition from morphological neighbors in secondary memory during cumulative retrieval-encoding cycles. Models of verbal recall need to be able to represent morphological as well as phonological and semantic information.

A neuronal gamma oscillatory signature during morphological unification in the left occipitotemporal junction

Morphology is the aspect of language concerned with the internal structure of words. In the past decades, a large body of masked priming (behavioral and neuroimaging) data has suggested that the visual word recognition system automatically decomposes any morphologically complex word into a stem and its constituent morphemes. Yet the reliance of morphology on other reading processes (e.g., orthography and semantics), as well as its underlying neuronal mechanisms are yet to be determined. In the current magnetoencephalography study, we addressed morphology from the perspective of the unification framework, that is, by applying the Hold/Release paradigm, morphological unification was simulated via the assembly of internal morphemic units into a whole word. Trials representing real words were divided into words with a transparent (true) or a nontransparent (pseudo) morphological relationship. Morphological unification of truly suffixed words was faster and more accurate and additionally enhanced induced oscillations in the narrow gamma band (60-85 Hz, 260-440 ms) in the left posterior occipitotemporal junction. This neural signature could not be explained by a mere automatic lexical processing (i.e., stem perception), but more likely it related to a semantic access step during the morphological unification process. By demonstrating the validity of unification at the morphological level, this study contributes to the vast empirical evidence on unification across other language processes. Furthermore, we point out that morphological unification relies on the retrieval of lexical semantic associations via induced gamma band oscillations in a cerebral hub region for visual word form processing.

Testing the stem dominance hypothesis: meaning analysis of inflected words and prepositional phrases

We tested the hypothesis that lexical-semantic access of inflected words is governed by the word stem. Object drawings overlaid with a dot/arrow marking position/movement were matched with corresponding linguistic expressions like “from the house”. To test whether the stem dominates lexical-semantic access irrespective of its position, we used Swedish prepositional phrases (locative information via preposition immediately preceding the stem) or Finnish case-inflected words (locative information via suffix immediately following the stem). Both in monolingual Swedish and in bilingual Finnish-Swedish speakers, correct stems with incorrect prepositions/case-endings were hardest to reject. This finding supports the view that the stem is indeed the dominant unit in meaning access of inflected words.

Real-time Functional Architecture of Visual Word Recognition

Despite a century of research into visual word recognition, basic questions remain unresolved about the functional architecture of the process that maps visual inputs from orthographic analysis onto lexical form and meaning and about the units of analysis in terms of which these processes are conducted. Here we use magnetoencephalography, supported by a masked priming behavioral study, to address these questions using contrasting sets of simple (walk), complex (swimmer), and pseudo-complex (corner) forms. Early analyses of orthographic structure, detectable in bilateral posterior temporal regions within a 150–230 msec time frame, are shown to segment the visual input into linguistic substrings (words and morphemes) that trigger lexical access in left middle temporal locations from 300 msec. These are primarily feedforward processes and are not initially constrained by lexical-level variables. Lexical constraints become significant from 390 msec, in both simple and complex words, with increased processing of pseudowords and pseudo-complex forms. These results, consistent with morpho-orthographic models based on masked priming data, map out the real-time functional architecture of visual word recognition, establishing basic feedforward processing relationships between orthographic form, morphological structure, and lexical meaning.