Does prime modality influence morphological processing?

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.

A study of base frequency in Spanish skilled and reading-disabled children: all children benefit from morphological processing in defining complex pseudowords

In this study, the base frequency (BF) effect is explored in reading-disabled and skilled readers of Spanish. A pseudoword definition task was completed by two groups of children. The pseudowords were composed from existing stems and affixes. The results show a facilitatory BF effect, suggesting that all children benefited from this aspect of morphology. A significant effect of group was also observed, showing that skilled readers scored better than reading-disabled children. The interaction between these variables was not significant. The overall pattern of data suggests that all children benefited from morphological processing to perform the definition task but that phonological difficulties in reading-disabled children prevented them from benefitting from the BF effect as much as their skilled peers.

Graded Effects of Regularity in Language Revealed by N400 Indices of Morphological Priming

Differential electrophysiological effects for regular and irregular linguistic forms have been used to support the theory that grammatical rules are encoded using a dedicated cognitive mechanism. The alternative hypothesis is that language systematicities are encoded probabilistically in a way that does not categorically distinguish rule-like and irregular forms. In the present study, this matter was investigated more closely by focusing specifically on whether the regular–irregular distinction in English past tenses is categorical or graded. We compared the ERP priming effects of regulars (baked–bake), vowel-change irregulars (sang–sing), and “suffixed” irregulars that display a partial regularity (suffixed irregular verbs, e.g., slept–sleep), as well as forms that are related strictly along formal or semantic dimensions. Participants performed a visual lexical decision task with either visual (Experiment 1) or auditory prime (Experiment 2). Stronger N400 priming effects were observed for regular than vowel-change irregular verbs, whereas suffixed irregulars tended to group with regular verbs. Subsequent analyses decomposed early versus late-going N400 priming, and suggested that differences among forms can be attributed to the orthographic similarity of prime and target. Effects of morphological relatedness were observed in the later-going time period, however, we failed to observe true regular–irregular dissociations in either experiment. The results indicate that morphological effects emerge from the interaction of orthographic, phonological, and semantic overlap between words.

Morphological facilitation for regular and irregular verb formations in native and non-native speakers: Little evidence for two distinct mechanisms

The authors compared performance on two variants of the primed lexical decision task to investigate morphological processing in native and non-native speakers of English. They examined patterns of facilitation on present tense targets. Primes were regular (billed-bill) past tense formations and two types of irregular past tense forms that varied on preservation of target length (fell-fall; taught-teach). When a forward mask preceded the prime (Exp. 1), language and prime type interacted. Native speakers showed reliable regular and irregular length preserved facilitation relative to orthographic controls. Non-native speakers' latencies after morphological and orthographic primes did not differ reliably except for regulars. Under cross-modal conditions (Exp. 2), language and prime type interacted. Native but not non-native speakers showed inhibition following orthographically similar primes. Collectively, reliable facilitation for regulars and patterns across verb type and task provided little support for a processing dichotomy (decomposition, non-combinatorial association) based on inflectional regularity in either native or non-native speakers of English.

Multiple dimensions of relatedness among words: Conjoint effects of form and meaning in word recognition

Words can be similar with respect to form (viz., spelling, pronunciation), meaning, or both form and meaning. In three lexical decision experiments (48 ms forward masked, 116 ms, and 250 ms SOAs), targets (e.g., FLOAT) followed prime words related by form only (e.g., COAT), meaning only (e.g., SWIM), or form and meaning (e.g., BOAT). BOAT-FLOAT and SWIM-FLOAT type pairs showed reduced target decision latencies relative to unrelated controls when primes were unmasked, but not when they were masked, and the magnitude of facilitation increased with increasing prime duration. By contrast, COAT-FLOAT type pairs produced significant inhibition at the shorter two prime durations. In all three experiments, including at the shortest SOA, (BOAT-FLOAT) pairs that shared form and meaning differed from COAT-FLOAT type pairs that shared only form. We discuss the similarity of the BOAT-FLOAT pattern to that of morphological facilitation and argue that if the same mechanism underlies both outcomes then activation of a shared morphemic representation need not underlie morphological facilitation.

What do graded effects of semantic transparency reveal about morphological processing?

We examined the influence of semantic transparency on morphological facilitation in English in three lexical decision experiments. Decision latencies to visual targets (e.g., CASUALNESS) were faster after semantically transparent (e.g., CASUALLY) than semantically opaque (e.g., CASUALTY) primes whether primes were auditory and presented immediately before onset of the target (Experiment 1a) or visual with an stimulus onset asynchrony (SOA) of 250 ms (Experiment 1b). Latencies did not differ at an SOA of 48 ms (Experiment 2) or with a forward mask at an SOA of 83 ms (Experiment 3). Generally, effects of semantic transparency among morphological relatives were evident at long but not at short SOAs with visual targets, regardless of prime modality. Moreover, the difference in facilitation after opaque and transparent primes was graded and increased with family size of the base morpheme.

Morphological processing: a comparison between free and bound stem facilitation

Linguists distinguish between words formed from free stems (e.g., actor: act) and those formed from bound stems (e.g., spectator: spect). In a forward masked priming task, we observed significant morphological facilitation for prime-target pairs that shared either a free (e.g., deform-CONFORM) or a bound (e.g., revive-SURVIVE) stem. Relative to an unrelated baseline, magnitudes of facilitation for free (e.g., form) and bound (e.g., vive) stems were significant and comparable, but relative to an orthographic baseline free stem facilitation was greater than bound stem facilitation. In addition, the magnitude of bound (but not free) stem morphological facilitation correlated with the number of morphological relatives.

Neural correlates of the effects of morphological family frequency and family size: an MEG study

Schreuder and Baayen (Schreuder. R., & Baayen, R. H. (1997). How complex simplex words can be. Journal of Memory and Language 37, 118-139) report that lexical decision times to nouns are not sensitive to the cumulative frequency of the noun's morphological derivatives in its "morphological family", even though such a cumulative frequency effect is obtained in the domain of inflection. Under a decomposition view of derivational morphology, this constitutes a puzzling exception to the robust finding that lexical frequency is one of the major determinants of behavioral response latencies. If morphologically complex words are decomposed, each occurrence of a member of a noun's morphological family should add to its root-frequency. We investigated the effects of morphological family frequency on the magnetoencephalographic response component M350, which shows sensitivity to factors affecting early stages of lexical processing, including lexical frequency. We hypothesized that high morphological family frequency should have a facilitory effect on the M350, even though no such effect can be seen in response time, presumably due to competition among possible root-affix combinations. Contrary to this hypothesis, we found that high family frequency elicits an M350 inhibition, suggesting that competition among morphological family members occurs at the M350. The result is significant, since there is evidence that competition among phonologically similar words occurs after, not at, the M350. Thus, our results suggest that competition within a morphological family precedes competition within a phonological similarity neighborhood.

Semantic aspects of morphological processing: transparency effects in Serbian

We examined the contribution of semantics to morphological facilitation in the visual lexical decision task at two stimulus onset asynchronies (SOAs) with Serbian materials. Primes appeared in Roman or Cyrillic characters. Targets always were printed in Roman. When primes were presented at an SOA of 250 msec, decision latencies to verbal targets (e.g., VOLIM) showed greatest facilitation after inflectionally (e.g., VOLE) related primes, significantly less after semantically transparent derived primes (e.g., ZAVOLE), and less again after semantically opaque derived primes (e.g., PREVOLE). Latencies after semantically transparent and opaque derived target words did not differ at an SOA of 48 msec. Both were slower than after inflectionally related primes. Stated generally, effects of semantic transparency among derivationally related verb forms were evident at long SOAs, but not at short ones. Under alphabet-alternating conditions, magnitudes of facilitation were greater overall, but the pattern was similar. The outcome suggests that restricted processing time for the prime limits the contribution of semantics to morphological processing and calls into question accounts that posit a task-invariant semantic criterion for morphological decomposition within the lexicon.