Cross-modal morphological priming in French

We investigated the lexical representation of morphologically complex words in French using a cross-modal priming experiment. We asked if the lexical representation for derivationally suffixed and prefixed words is morphologically structured and how this relates to the phonological transparency of the surface relationship between stem and affix. Overall we observed a clear effect of the morphological structure for derived words, an effect that is not explicable by a formal effect. Prefixed words prime their stems, even when they have a phonologically opaque relationship, and a prefixed word primes another prefixed word derived from the same stem. However, suffixed words prime their stems only if their relationship is phonologically transparent. Two suffixed words derived from the same stem prime each other. These two latter results differ from those observed in English by Marslen-Wilson, Tyler, Waksler, and Older (1994). We argue that it is the specific properties of the language, such as rhythm, that could explain the differences between the results observed for the two languages and we propose a model where prefixed and suffixed words are decomposed at different stages during their identification process.     

New evidence for morphological errors in deep dyslexia

Morphological errors in reading aloud (e.g., sexist-->sexy) are a central feature of the symptom-complex known as deep dyslexia, and have historically been viewed as evidence that representations at some level of the reading system are morphologically structured. However, it has been proposed (Funnell, 1987) that morphological errors in deep dyslexia are not morphological in nature but are actually a type of visual error that arises when a target word that cannot be read aloud (by virtue of its low imageability and/or frequency) is modified to form a visually similar word that can be read aloud (by virtue of its higher imageability and/or frequency). In the work reported here, the deep dyslexic patient DE read aloud lists of genuinely suffixed words (e.g., killer), pseudosuffixed words (e.g., corner), and words with non-morphological embeddings (e.g., cornea). Results revealed that the morphological status of a word had a significant influence on the production of stem errors (i.e., errors that include the stem or pseudostem of the target): genuinely suffixed words yielded more stem errors than pseudosuffixed words or words with non-morphological embeddings. This effect of morphological status could not be attributed to the relative levels of target and stem imageability and/or frequency. We argue that this pattern of data indicates that apparent morphological errors in deep dyslexic reading are genuinely morphological, and discuss the implications of these errors for theories of deep dyslexia.     

Do transposed-letter similarity effects occur at a morpheme level? Evidence for morpho-orthographic decomposition

When does morphological decomposition occur in visual word recognition? An increasing body of evidence suggests the presence of early morphological processing. The present work investigates this issue via an orthographic similarity manipulation. Three masked priming lexical decision experiments were conducted to examine the transposed-letter similarity effect (e.g., jugde facilitates JUDGE more than the control jupbe) in polymorphemic and monomorphemic words. If morphological decomposition occurs at early stages of visual word recognition, we would expect an interaction with transposed-letter effects. Experiment 1 was carried out in Basque, which is an agglutinative language. The nonword primes were created by transposing two letters that either crossed the morphological boundaries of suffixes or did not. Results showed a transposed-letter effect for non-affixed words, whereas there were no signs of a transposed-letter effect across morpheme boundaries for affixed words. In Experiment 2, this issue was revisited in a non-agglutinative language (Spanish), with prefixed and suffixed word pairs. Again, results showed a significant transposed-letter effect for non-affixed words, whereas there were no signs of a transposed-letter effect across morpheme boundaries for affixed words (both prefixed words and suffixed words). Experiment 3 replicated the previous findings, and also revealed that, for polymorphemic words, transposed-letter priming effects occurred for within-morpheme transpositions. Taken together, these findings support the view that morphological decomposition operates at an early stage of visual word recognition.     

Compound word effects differ in reading,on-line naming,and delayed naming tasks

Bimorphemic compound words (e.g.,blueberry), bimorphemic suffixed words (e.g.,ceaseless), and monomorphemic controls (e.g.,arthritis) were read in neutral sentence contexts in Experiment 1. The main result revealed longer first fixation durations on compound words than on control and suffixed words. Different effects emerged when naming tasks were used. An on-line naming task revealed substantially shorter naming latencies for compound words than for control and suffixed words. Naming latencies for compound and control words were equivalent in a delayed naming task. These results indicate that on-line naming latencies and word-viewing durations may yield diverging results. They also suggest that activation of constituent words of compound words occurs independently from the specification of conventional word meanings.     

Early morphological decomposition during visual word recognition: Evidence from masked transposed-letter priming

The present experiments were designed to explore the theory of early morpho-orthographic segmentation (Rastle, Davis, & New, Psychonomic Bulletin & Review 11,1090–1098, 2004), which postulates that written words with a true morphologically complex structure (cleaner) and those with a morphological pseudostructure (corner) are both decomposed into affix and stem morphemes. We used masked complex transposed-letter (TL) nonword primes in a lexical decision task. Experiment 1 replicated the well-known masked TL-priming effect using monomorphemic nonword primes (e.g., wran–WARN). Experiment 2 used the same nonword TL stems as in Experiment 1, but combined them with real suffixes (e.g., ish as in wranish–WARN). Priming was compared with that from nonsuffixed primes in which the real suffixes were replaced with nonmorphemic endings (e.g., el as in wranel–WARN). Significant priming was found in the suffixed but not in the nonsuffixed condition, suggesting that affix-stripping occurs at prelexical stages in visual word recognition and operates over early letter-position encoding mechanisms.     

Does prime modality influence morphological processing?

Facilitation among morphologically related words generally is impervious to the prefixed or suffixed structure of primes and targets. A notable exception arises, however, when both primes and targets are suffixed. More specifically, when primes are auditory and targets are visual, facilitation for a suffixed target (e.g., payment) is absent when it follows a prime (e.g., payable) that is morphologically related and suffixed (Marslen-Wilson, Tyler, Waksler, & Older, 1994). To account for null facilitation (viz., the "suffix-suffix" effect), Marslen-Wilson and his colleagues posit inhibitory links between suffixes of morphological relatives. The present study assesses the generality of the "suffix-suffix" effect. When morphological facilitation is assessed relative to an orthographically related baseline, suffixed primes facilitate derivationally as well as inflectionally related morphological targets when primes are visual as well as auditory in both the lexical decision and naming tasks. The present findings call into question lexical models that posit inhibitory links between suffixes of morphological relatives.     

Parallel processing of whole words and morphemes in visual word recognition

Models of morphological processing make different predictions about whether morphologically complex written words are initially decomposed and recognized on the basis of their morphemic subunits or whether they can directly be accessed as whole words and at what point semantics begin to influence morphological processing. In this study, we used unprimed and masked primed lexical decision to compare truly suffixed (darkest) and pseudosuffixed words (glossary) with within-boundary (d ra kest/g ol ssary) to across-boundary (dar ek st/glos as ry) letter transpositions. Significant transposed-letter similarity effects were found independently of the morphological position of the letter transposition, demonstrating that, in English, morphologically complex whole-word representations can be directly accessed at initial word processing stages. In a third masked primed lexical decision experiment, the same materials were used in the context of stem target priming, and it was found that truly suffixed primes facilitate the recognition of their stem-target (darkest-DARK) to the same extent as pseudosuffixed primes (glossary-GLOSS), which is consistent with theories of early morpho-orthographic decomposition. Taken together, our findings provide evidence for both whole-word access and morphological decomposition at initial stages of visual word recognition and are discussed in the context of a hybrid account.     

Completion norms for 40 three-letter word stems

This is a report of the completion responses for 40 three-letter word stems (e.g., ABO) produced by 100 undergraduate students at the University of California at San Diego. The report includes a list of the different words that were written as stem completions, their frequency of occurrence as completions, and their frequency of occurrence in English according to published norms. This list of materials is useful for the construction of completion tests for future investigations of direct priming phenomena, and it may provide an important covariate in the analysis of performance on completion tests. Preliminary analyses of the results reveal three primary factors that determine overall performance on a stem-completion test: word frequency, word length, and meanings per word. Analyses of the completions produced for each individual word stem, however, reveal that usually only one of these factors makes a significant contribution to performance.     

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.     

Interference in implicit memory caused by processing of interpolated material

This study addresses the susceptibility of implicit memory to interference. Interference is manipulated by presenting interpolated lists of words that do or do not have word stems in common with previously studied target words (e.g., target word paragraph followed by interpolated words such as paradise or vicinity). Interference in a word stem completion task occurred only when words had similar word stems (Experiment 1). Increasing the number of interpolated words with corresponding word stems (e.g., not only paradise but also parking, pardon, and parliament) produced increasing amounts of interference (Experiment 2). Interference in implicit memory appears to be a simple response competition phenomenon that occurs when cues simultaneously activate primed targets and primed competing responses. The amount of interference can be explained by a quantitative model of the relative strengths of target and competing responses.     

Word frequency and root-morpheme frequency effects on processing of Korean particle-suffixed words

Two experiments investigated the roles of the frequency of the root morpheme and the frequency of the whole word for a particular type of suffixed word in Korean in which the suffixed word can be thought of as a phrase (e.g., grandson-with). In both experiments, sentence frames were constructed so that they could have one of two target words that varied on frequency characteristics in the same location in the sentence. In Experiment 1, the frequency of the root morpheme was varied with the frequency of the word controlled, and in Experiment 2, the frequency of the word was varied with the frequency of the root morpheme controlled. Word frequency had a significant effect on fixation times, whereas root morpheme frequency did not. The results were surprising as native Korean speakers view the root morpheme as the “word” (analogous to how English readers would view a noun followed by a prepositional phrase).     

Recognition of affixed words and the word frequency effect

Three experiments are reported in which the word frequency effect is used as a diagnostic for determining whether affixed words coming from the same stem are stored together or separately in the lexicon. Prefixed words are examined in the first experiment, inflected words in the second and third. In the first two experiments, two types of word are compared where the words in each condition are matched on surface or presented frequency but are varied on the frequency of their stems or base frequency. It is found that lexical decision times are influenced by base frequency, thus indicating that words related by affixation are stored together in the lexicon. The third experiment, however, demonstrates that when base frequency is held constant and surface frequency is varied, lexical decision times are influenced by surface frequency. The results are accounted for by a model of word recognition whereby frequency has its effect at two different stages of the recognition process.     

The role of memory consolidation in generalisation of new linguistic information

Accounts of memory that postulate complementary learning systems (CLS) have become increasingly influential in the field of language learning. These accounts predict that generalisation of newly learnt linguistic information to untrained contexts requires offline memory consolidation. Such generalisation should not be observed immediately after training, as these accounts claim unconsolidated representations are context and hippocampus-dependent and gain contextual and hippocampal independence only after consolidation. We trained participants on new affixes (e.g., -nule) attached to familiar word stems (e.g., buildnule), testing them immediately or 2days later. Participants showed an immediate advantage for trained affixes in a speeded shadowing task as long as these affixes occurred in the stem contexts in which they were learnt (e.g., buildnule). This learning effect generalised to words with untrained stems (e.g., sailnule) only in the delayed test condition. By contrast, a non-speeded definition selection task showed immediate generalisation. We propose that generalisation can be supported by initial context-dependent memories given sufficient processing time, but that context-independent lexical representations emerge only following consolidation, as predicted by CLS accounts.     

Semantic similarity influences early morphological priming in Serbian: A challenge to form-then-meaning accounts of word recognition

Semantically similar (e.g., coolant-COOL) primes have produced greater facilitation than have form-similar but semantically dissimilar (e.g., rampant-RAMP) primes when English words have appeared in the forward-masked primed lexical decision task (Feldman, O'Connor, & Moscoso del Prado Martín, Psychonomic Bulletin & Review 16: 684-691, 2009). These results challenge claims that form-based, semantically blind activation underlies early morphological facilitation. Some have argued that the English materials in previous studies were not ideally constructed, insofar as the types of spelling changes to affixed stems differed in the semantically similar and dissimilar pairs. The present study exploited Serbian's bialphabetism, rich morphology, and homographic (form-identical) stems to replicate early effects of semantic similarity. Furthermore, it incorporated within-target manipulations of prime type and of alphabet, such that the alphabets of the prime-target pairs matched in Experiment 1a and alternated in Experiment 1b. Importantly, no letter or phoneme changes occurred between the stems of the primes and targets. These results revealed significant effects of semantic similarity that are comparable with and without alphabet alternation. The semantic effects in Serbian replicated almost exactly those in English (Feldman et al., Psychonomic Bulletin & Review 16: 684-691, 2009), which suggests that even early in the course of processing, morphemes are units of meaning as well as of form. The results failed to support models of lexical processing that postulate sequential access, first to the morphological form, and then to the semantic aspects of words.     

In what sense is implicit memory "episodic"? The effect of reinstating environmental context

We consider three aspects of the term episodic. Previous literature shows implicit memory does not make conscious autobiographical reference but does code an item's intrinsic context (e.g., perceptual detail). Here, we consider extrinsic context--namely, that not directly processed as part of item identification and not overtly relevant to the task. Study-test mismatch in environmental context (outdoors vs. indoors) reduced memory in an explicit stem-cued recall task but had no effect on repetition priming in an implicit stem completion task. This was true even for very low frequency words. We support the view that implicit memory reflects traces within perceptual (or semantic) knowledge-based systems that are instance specific but do not code the full spatiotemporal context information necessary to support conscious recollection. We also interpret our results as consistent with differences in environmental context specificity between free recall and recognition.     

Number of solutions effects in stem decision: support for the distinction between identification and production processes in priming

Three experiments explored the distinction between identification and production processes (e.g., Gabrieli et al., 1999). A stem decision test was introduced, in which participants were asked to state whether there were any English words that began with the presented three-letter stems. In Experiment 1, stem decision priming was robust for single-solution stems, but much reduced for many-solution stems. In Experiment 2, the solutions effect in stem decision was replicated in a within-subjects design, as was the contrast between the presence of priming in a many-solution stem completion test and the absence of priming in a many-solution stem decision test. In Experiment 3, for each critical many-solution stem in the stem decision test, participants studied three words that began with those three letters. Again, priming was not observed. These results were consistent with the notions that (a) many-solution stem completion relies on production processes, (b) the stem decision test eliminates production processes, and (c) single-solution priming relies on identification processes, regardless of whether the test is stem completion or stem decision.     

Number of solutions effects in stem decision: Support for the distinction between identification and production processes in priming

Three experiments explored the distinction between identification and production processes (e.g., Gabrieli et al., 1999). A stem decision test was introduced, in which participants were asked to state whether there were any English words that began with the presented three-letter stems. In Experiment 1, stem decision priming was robust for single-solution stems, but much reduced for many-solution stems. In Experiment 2, the solutions effect in stem decision was replicated in a within-subjects design, as was the contrast between the presence of priming in a many-solution stem completion test and the absence of priming in a many-solution stem decision test. In Experiment 3, for each critical many-solution stem in the stem decision test, participants studied three words that began with those three letters. Again, priming was not observed. These results were consistent with the notions that (a) many-solution stem completion relies on production processes, (b) the stem decision test eliminates production processes, and (c) single-solution priming relies on identification processes, regardless of whether the test is stem completion or stem decision.     

The broth in my brother’s brothel: Morpho-orthographic segmentation in visual word recognition

Much research suggests that words comprising more than one morpheme are represented in a “decomposed” manner in the visual word recognition system. In the research presented here, we investigate what information is used to segment a word into its morphemic constituents and, in particular, whether semantic information plays a role in that segmentation. Participants made visual lexical decisions to stem targets preceded by masked primes sharing (1) a semantically transparent morphological relationship with the target (e.g.,cleaner-CLEAN), (2) an apparent morphological relationship but no semantic relationship with the target (e.g.,corner-CORN), and (3) a nonmorphological form relationship with the target (e.g.,brothel-BROTH). Results showed significant and equivalent masked priming effects in cases in which primes and targets appeared to be morphologically related, and priming in these conditions could be distinguished from nonmorphological form priming. We argue that these findings suggest a level of representation at which apparently complex words are decomposed on the basis of their morpho-orthographic properties. Implications of these findings for computational models of reading are discussed.     

Emotion words affect eye fixations during reading

Emotion words are generally characterized as possessing high arousal and extreme valence and have typically been investigated in paradigms in which they are presented and measured as single words. This study examined whether a word's emotional qualities influenced the time spent viewing that word in the context of normal reading. Eye movements were monitored as participants read sentences containing an emotionally positive (e.g., lucky), negative (e.g., angry), or neutral (e.g., plain) word. Target word frequency (high or low) was additionally varied to help determine the temporal locus of emotion effects, with interactive results suggesting an early lexical locus of emotion processing. In general, measures of target fixation time demonstrated significant effects of emotion and frequency as well as an interaction. The interaction arose from differential effects with negative words that were dependent on word frequency. Fixation times on emotion words (positive or negative) were consistently faster than those on neutral words with one exception-high-frequency negative words were read no faster than their neutral counterparts. These effects emerged in the earliest eye movement measures, namely, first and single fixation duration, suggesting that emotionality, as defined by arousal and valence, modulates lexical processing. Possible mechanisms involved in processing emotion words are discussed, including automatic vigilance and desensitization, both of which imply a key role for word frequency. Finally, it is important that early lexical effects of emotion processing can be established within the ecologically valid context of fluent reading.     

How to drastically reduce priming in word stem completion—and still present the words

This paper describes a series of experiments in which we demonstrated that "dysphonemic" word stems, which are likely not pronounced in isolation as they are within a word (e.g., MUS in MUSHROOM or LEG in LEGEND), showed less priming than did "phonemic stems" (e.g., MUS in MUSTARD or LEG in LEGACY). Furthermore, words with either dysphonemic or phonemic three-letter stems gave rise to equivalent levels of priming when test cues were four-letter stems (LEGE) or word fragments (L_G_ND). Moreover, the difference between phonemic and dysphonemic stems persisted when nonpresented completion rates were matched. A final cued-recall experiment revealed that performance was greater for phonemic stems than for dysphonemic stems and that this difference was greater for older participants than for younger ones. These results are not readily accounted for by extant theoretical approaches and point to important methodological issues regarding stem completion.