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.
Abstract: Morphology is a major organising principle of English and other alphabetic languages, but has been largely neglected in theories of reading acquisition. In this article, I develop 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. I show that morphology provides an important degree of regularity across this mapping in English, and suggest that this regularity is directly associated with irregularity in the mapping between spelling and sound. I further show that while children in primary school display explicit knowledge of morphological relationships, there is scant evidence they show the rapid morphological analysis of printed words that skilled readers exhibit. These findings suggest that the acquisition of long-term morphological knowledge may be associated with the ongoing development of reading expertise. Implications for reading instruction are discussed.
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.
Abstract: There is much evidence that visual recognition of morphologically complex words (e.g., teacher) proceeds via a decompositional route, first involving recognition of their component morphemes (teach + -er). According to the Full Decomposition model, after the visual decomposition stage, followed by morpheme lookup, there is a final "recombination" stage, in which the decomposed morphemes are combined and the well-formedness of the complex form is evaluated. Here, we use MEG to provide evidence for the temporally-differentiated stages of this model. First, we demonstrate an early effect of derivational family entropy, corresponding to the stem lookup stage; this is followed by a surface frequency effect, corresponding to the later recombination stage. We also demonstrate a late effect of a novel statistical measure, semantic coherence, which quantifies the gradient semantic well-formedness of complex words. Our findings illustrate the usefulness of corpus measures in investigating the component processes within visual word recognition.
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: A new general theory of acquired similarity and knowledge representation, latent semantic analysis (LSA), is presented and used to successfully simulate such learning and several other psycholinguistic phenomena.
Abstract: How do people know as much as they do with as little information as they get? The problem takes many forms; learning vocabulary from text is an especially dramatic and convenient case for research. A new general theory of acquired similarity and knowledge representation, latent semantic analysis (LSA), is presented and used to successfully simulate such learning and several other psycholinguistic phenomena. By inducing global knowledge indirectly from local co-occurrence data in a large body of representative text, LSA acquired knowledge about the full vocabulary of English at a comparable rate to schoolchildren. LSA uses no prior linguistic or perceptual similarity knowledge; it is based solely on a general mathematical learning method that achieves powerful inductive effects by extracting the right number of dimensions (e.g., 300) to represent objects and contexts. Relations to other theories, phenomena, and problems are sketched.
6,014 citations
"Evidence for early morphological de..." refers background in this paper
...According to semantic relatedness values (Latent Semantic Analysis; Landauer & Dumais, 1997), the prime–target pairs in the transparent condition were significantly more related semantically than in the opaque and orthographic conditions, which, in turn, did not differ from each other in terms of the semantic relatedness (see Rastle et al., 2004, for a statistical summary of the stimulus characteristics)....
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...According to semantic relatedness values (Latent Semantic Analysis; Landauer & Dumais, 1997), the prime–target pairs in the transparent condition were significantly more related semantically than in the opaque and orthographic conditions, which, in turn, did not differ from each other in terms of…...
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TL;DR: DMDX is a Windows-based program designed primarily for language-processing experiments that uses the features of Pentium class CPUs and the library routines provided in DirectX to provide accurate timing and synchronization of visual and audio output.
Abstract: DMDX is a Windows-based program designed primarily for language-processing experiments. It uses the features of Pentium class CPUs and the library routines provided in DirectX to provide accurate timing and synchronization of visual and audio output. A brief overview of the design of the program is provided, together with the results of tests of the accuracy of timing. The Web site for downloading the software is given, but the source code is not available.
2,541 citations
"Evidence for early morphological de..." refers methods in this paper
...The stimuli were presented using DMDX (Forster & Forster, 2003)....
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TL;DR: It is concluded that connectionists' claims about the dispensability of rules in explanations in the psychology of language must be rejected, and that, on the contrary, the linguistic and developmental facts provide good evidence for such rules.
Abstract: Does knowledge of language consist of mentally-represented rules? Rumelhart and McClelland have described a connectionist (parallel distributed processing) model of the acquisition of the past tense in English which successfully maps many stems onto their past tense forms, both regular (walk/walked) and irregular (go/went), and which mimics some of the errors and sequences of development of children. Yet the model contains no explicit rules, only a set of neuronstyle units which stand for trigrams of phonetic features of the stem, a set of units which stand for trigrams of phonetic features of the past form, and an array of connections between the two sets of units whose strengths are modified during learning. Rumelhart and McClelland conclude that linguistic rules may be merely convenient approximate fictions and that the real causal processes in language use and acquisition must be characterized as the transfer of activation levels among units and the modification of the weights of their connections. We analyze both the linguistic and the developmental assumptions of the model in detail and discover that (1) it cannot represent certain words, (2) it cannot learn many rules, (3) it can learn rules found in no human language, (4) it cannot explain morphological and phonological regularities, (5) it cannot explain the differences between irregular and regular forms, (6) it fails at its assigned task of mastering the past tense of English, (7) it gives an incorrect explanation for two developmental phenomena: stages of overregularization of irregular forms such as bringed, and the appearance of doubly-marked forms such as ated and (8) it gives accounts of two others (infrequent overregularization of verbs ending in t/d, and the order of acquisition of different irregular subclasses) that are indistinguishable from those of rule-based theories. In addition, we show how many failures of the model can be attributed to its connectionist architecture. We conclude that connectionists' claims about the dispensability of rules in explanations in the psychology of language must be rejected, and that, on the contrary, the linguistic and developmental facts provide good evidence for such rules.
1,439 citations
TL;DR: The authors showed that the frequency attenuation effect is a product of the involvement of the episodic memory system in the lexical decision process, which is supported by the demonstration of constant repetition effects for high and low-frequency words when the priming stimulus is masked; the masking is assumed to minimize the influence of any possible episodic trace of the prime.
Abstract: Repetition priming effects in lexical decision tasks are stronger for low-frequency words than for high-frequency words. This frequency attenuation effect creates problems for frequency-ordered search models that assume a relatively stable frequency effect. The suggestion is made that frequency attenuation is a product of the involvement of the episodic memory system in the lexical decision process. This hypothesis is supported by the demonstration of constant repetition effects for high- and low-frequency words when the priming stimulus is masked; the masking is assumed to minimize the influence of any possible episodic trace of the prime. It is further shown that long-term repetition effects are much less reliable when the subject is not required to make a lexical decision response to the prime. When a response is required, the expected frequency attenuation effect is restored. It is concluded that normal repetition effects consist of two components: a very brief lexical effect that is independent of frequency and a long-term episodic effect that is sensitive to frequency. There has been much recent interest in the fact that in a lexical decision experiment, where subjects are required to classify letter strings as words or nonwords, there is a substantial increase in both the speed and the accuracy of classificatio n for words that are presented more than once during the experiment, even though considerable time may have elapsed between successive presen
1,324 citations
"Evidence for early morphological de..." refers background in this paper
...Masked priming has proven to be a powerful psycholinguistic tool in assessing lexical processes and representation (Forster, 1998; Forster & Davis, 1984)....
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Book•
03 Jan 1986
TL;DR: The authors presented an alternative to the standard rule-based account of a child's acquisition of the past tense in English by dispensing with the assumption that the child learns rules and substituting in its place a simple homogeneous learning procedure.
Abstract: : This paper presents an alternative to the standard rule based account of a child's acquisition of the past tense in English. Children are typically said to pass through a three-phase acquisition process in which they first learn past tense by rote, then learn the past tense rule and over regularize, and then finally learn the exceptions to the rule. We show that the acquisition data can be accounted for in more detail by dispensing with the assumption that the child learns rules and substituting in its place a simple homogeneous learning procedure. We show how rule-like behavior can emerge from the interactions among a network of units encoding the root form to past tense mapping. A large computer simulation of the learning process demonstrates the operating principles of our alternative account, shows how details of the acquisition process not captured by the rule account emerge, and makes predictions about other details of the acquisition process not yet observed. Keywords: Learning; networks; Language; Verbs; Perceptions; Morphology.
1,210 citations