Evidence for early morphological decomposition: Combining masked priming with magnetoencephalography
TL;DR: Data regarding the transitional probability from stem to affix in a post hoc comparison is presented, which suggests that this factor may modulate early morphological decomposition, particularly for opaque words.
Abstract: Are words stored as morphologically structured representations? If so, when during word recognition are morphological pieces accessed? Recent masked priming studies support models that assume early decomposition of (potentially) morphologically complex words. The electrophysiological evidence, however, is inconsistent. We combined masked morphological priming with magneto-encephalography (MEG), a technique particularly adept at indexing processes involved in lexical access. The latency of an MEG component peaking, on average, 220 msec post-onset of the target in left occipito-temporal brain regions was found to be sensitive to the morphological prime-target relationship under masked priming conditions in a visual lexical decision task. Shorter latencies for related than unrelated conditions were observed both for semantically transparent (cleaner-CLEAN) and opaque (corner-CORN) prime-target pairs, but not for prime-target pairs with only an orthographic relationship (brothel-BROTH). These effects are likely to reflect a prelexical level of processing where form-based representations of stems and affixes are represented and are in contrast to models positing no morphological structure in lexical representations. Moreover, we present data regarding the transitional probability from stem to affix in a post hoc comparison, which suggests that this factor may modulate early morphological decomposition, particularly for opaque words. The timing of a robust MEG component sensitive to the morphological relatedness of prime-target pairs can be used to further understand the neural substrates and the time course of lexical processing.
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01 Jan 1985
TL;DR: This paper discusses one aspect of the lexicon, namely its morphological organization, and describes this kind of lexicon system as most suited for describing suffixing languages with a comparatively high degree of agglutination.
Abstract: 1. In trod u otion In this paper, I w ill discuss one aspect of the lexicon, namely its morphological organization. For about two years I have been working with Koakenniemi's twolevel model (Koakenniemi 1983)i on a Polish two-level description. In this work, I have become more and more Interested in the formalism it s e l f , something that has tended to push work on the language description into the background. It seems to be the case that in moat concrete two-level descriptions, the rule component is forced to carry too heavy a burden in comparison with the lexicon, perhaps because the lexicon is very simple as to its implementation. Like many other lexical systems in computer applications i t is implemented as a tree, with a root node and leaves, from which the lexical entries eire retrieved when the analysts routine has traversed the tree. The twolevel lexicon la a bit more sophisticated than th is , however, in that there la not only one, but several lexicon trees, the so called minilexicons. The user links the mlnilexicona into a whole, moat often into a root lexicon and a number of su ffix lexicons. In Hockett'a terminology, we could apeak of an Itern-and-Arrangement (lA) model (Hockett 1958, pp 386ff). Elsewhere I have characterized this kind of lexicon system as most suited for describing suffixing languages with a comparatively high degree of agglutination (Borin 1985f p 35); This is mainly due to the fact that the system works according to what Blåberg (1984, p 6 l) aptly has termed the "forget-where-you-came-from"
261 citations
TL;DR: The data support a model of word recognition in which decomposition is attempted, and possibly utilized, for complex words containing bound roots as well as free word-stems, and find evidence of decomposition for both free stems and bound roots at the M170 stage in processing.
Abstract: We employ a single-trial correlational MEG analysis technique to investigate early processing in the visual recognition of morphologically complex words. Three classes of affixed words were presented in a lexical decision task: free stems (e.g., taxable), bound roots (e.g., tolerable), and unique root words (e.g., vulnerable, the root of which does not appear elsewhere). Analysis was focused on brain responses within 100-200 msec poststimulus onset in the previously identified letter string and visual word-form areas. MEG data were analyzed using cortically constrained minimum-norm estimation. Correlations were computed between activity at functionally defined ROIs and continuous measures of the words' morphological properties. ROIs were identified across subjects on a reference brain and then morphed back onto each individual subject's brain (n = 9). We find evidence of decomposition for both free stems and bound roots at the M170 stage in processing. The M170 response is shown to be sensitive to morphological properties such as affix frequency and the conditional probability of encountering each word given its stem. These morphological properties are contrasted with orthographic form features (letter string frequency, transition probability from one string to the next), which exert effects on earlier stages in processing (â¼130 msec). We find that effects of decomposition at the M170 can, in fact, be attributed to morphological properties of complex words, rather than to purely orthographic and form-related properties. Our data support a model of word recognition in which decomposition is attempted, and possibly utilized, for complex words containing bound roots as well as free word-stems.
129 citations
TL;DR: The view that learning to appreciate morphological relationships may be a vital part of acquiring a direct mapping between printed words and their meanings, represented in the ventral brain pathway of the reading network is developed.
91 citations
TL;DR: This work uses MEG to provide evidence for the temporally-differentiated stages of the Full Decomposition model, and demonstrates an early effect of derivational family entropy, corresponding to the stem lookup stage, and a late effect of a novel statistical measure, semantic coherence, which quantifies the gradient semantic well-formedness of complex words.
68 citations
Cites background from "Evidence for early morphological de..."
...Taking advantage of the temporal resolution of MEG, here we separately examine both the hypothesized earlier derivational family entropy effect on lexical access for a stem, as well as the hypothesized later surface frequency effect on recombination of stem and affix....
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...Using MEG, Lehtonen, Monahan, and Poeppel (2011) found similar effects for regular derived words at a latency of !...
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References
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TL;DR: Results indicated priming effects associated with the mere appearance of morphological structure (cornerCORN) provided a neurobiological basis for a purely structural morphemic segmentation mechanism operating at early stages of visual word recognition.
Abstract: Considerable behavioral research has demonstrated that the visual word recognition system is sensitive to morphological structure. It has typically been assumed that analysis of morphologically complex words occurs only when the meaning of these words can be derived from the meanings of their constituents (e.g., hunter = hunt + er). However, results from recent behavioral research using the masked priming technique have demonstrated that morphological analysis can occur at an earlier orthographic level, in cases in which the meanings of complex words cannot be derived from their constituents (e.g., corner = corn + er). Here, we combine the logic of behavioral masked priming with the neurophysiological phenomenon of functional magnetic resonance imaging priming suppression to look for evidence of nonsemantic morphological priming at the neural level. Both behavioral and functional magnetic resonance imaging results indicated priming effects associated with the mere appearance of morphological structure (corner---CORN). In addition, these effects were distinguishable from lexical-semantic effects (bucket---PAIL) and orthographic effects (brothel---BROTH). Three left-lateralized occipito-temporal regions showed sensitivity to early morphological components of visual word recognition. Two of these regions also showed orthographic priming (∼BA 37, peak: -48 -60 -17; ∼BA 19, peak: -40 -77 -1), whereas one was sensitive only to morphological similarity between primes and targets (∼BA 19, peak: ∼37 ∼67 ∼7). These findings provide a neurobiological basis for a purely structural morphemic segmentation mechanism operating at early stages of visual word recognition.
105 citations
"Evidence for early morphological de..." refers background in this paper
...…to left (or bilateral) posterior occipital and temporal regions, similar to the sources that have been found for the M170 component (see, e.g., Pylkkänen & Okano, 2010; Harris et al., 2008; Pylkkänen et al., 2006; see also Gold & Rastle, 2007, for an fMRI study onmaskedmorphological priming)....
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TL;DR: This article investigated the neural bases of morphological decomposition with magnetoencephalography (MEG) and found that morphologically complex forms display larger amplitudes in the M170, the same component that has been implicated for letterstring and face effects.
Abstract: Recent masked priming studies on visual word recognition have suggested that morphological decomposition is performed prelexically, purely on the basis of the orthographic properties of the word form. Given this, one might expect morphological complexity to modulate early visual evoked activity in electromagnetic measures. We investigated the neural bases of morphological decomposition with magnetoencephalography (MEG). In two experiments, we manipulated morphological complexity in single word lexical decision without priming, once using suffixed words and once using prefixed words. We found that morphologically complex forms display larger amplitudes in the M170, the same component that has been implicated for letterstring and face effects in previous MEG studies. Although letterstring effects have been reported to be left-lateral, we found a right-lateral effect of morphological complexity, suggesting that both hemispheres may be involved in early analysis of word forms.
83 citations
"Evidence for early morphological de..." refers background in this paper
...Apart from Zweig and Pylkkänen (2009), direct contrasts between visually presented morphologically complex and simple words in the standard visual lexical decision (without priming or other manipulations) have not usually found robust effects that could directly be attributed to early visual…...
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...Using MEG, Zweig and Pylkkänen (2009) investigated the influence of morphology on early word recognition by contrasting morphologically complex (derived) words (e.g., farmer, refill) directly with monomorphemic words (e.g., switch) and orthographic control words (e.g.,winter, reckon) in a lexical decision task....
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...The aim of the present study was to investigate the nature of early morphological decomposition by combining masked priming with MEG, an electrophysiological technique that has been found to be useful in probing different levels of lexical processing....
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...Using MEG, Zweig and Pylkkänen (2009) investigated the influence of morphology on early word recognition by contrasting morphologically complex (derived) words (e.g., farmer, refill) directly with monomorphemic words (e.g., switch) and orthographic control words (e.g.,winter, reckon) in a lexical…...
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...We investigate whether more clear-cut electrophysiological evidence for internally structured early representations can be found using MEG, a technique that has not yet been employed in studying effects of masked morphological priming....
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TL;DR: This article used whole-head magnetoencephalography to measure the spatio-temporal dynamics of brain responses, and investigated their sensitivity to lexicality (defined here as the difference between words and consonant strings), word length, and variation in letter position.
Abstract: Neuroimaging and lesion studies suggest that occipito-temporal brain areas play a necessary role in recognizing a wide variety of objects, be they faces, letters, numbers, or household items. However, many questions remain regarding the details of exactly what kinds of information are processed by the occipito-temporal cortex. Here, we address this question with respect to reading. Ten healthy adult subjects performed a single word reading task. We used whole-head magnetoencephalography to measure the spatio-temporal dynamics of brain responses, and investigated their sensitivity to: (1) lexicality (defined here as the difference between words and consonant strings), (2) word length, and (3) variation in letter position. Analysis revealed that midline occipital activity around 100 msec, consistent with low-level visual feature analysis, was insensitive to lexicality and variation in letter position, but was slightly affected by string length. Bilateral occipito-temporal activations around 150 msec were insensitive to lexicality and reacted to word length only in the timing (and not strength) of activation. However, vertical shifts in letter position revealed a hemispheric imbalance: The right hemisphere activation increased with the shifts, whereas the opposite pattern was evident in the left hemisphere. The results are discussed in the light of Caramazza and Hillis's (1990) model of early reading.
77 citations
TL;DR: An MEG study of pseudo-affixed words like brother, which masked priming studies have shown are decomposed in recognition, which confirms the position that the IT does represent the visual word forms of morphemes and performs morphological decomposition modulated by the statistical relations between morphhemes by 170 ms post presentation.
76 citations
"Evidence for early morphological de..." refers result in this paper
...…the complex word form and its stem has been suggested to affect the ease or difficulty of decomposition (Hay, 2001), and recent MEG studies by Lewis, Solomyak, and Marantz (2011) and Solomyak and Marantz (2010) found that the left hemisphere M170 component, which may be related to the…...
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TL;DR: Generally, effects of semantic transparency among morphological relatives were evident at long but not at short SOAs with visual targets, regardless of prime modality.
74 citations