Takao Fushimi

The Functional Unit in Phonological Encoding: Evidence for Moraic Representation in Native Japanese Speakers.

Speech production studies have shown that the phonological form of a word is made up of phonemic segments in stress-timed languages (e.g., Dutch) and of syllables in syllable-timed languages (e.g., Chinese). To clarify the functional unit of mora-timed languages, the authors asked native Japanese speakers to perform an implicit priming task (A. S. Meyer, 1990, 1991). In Experiment 1, participants could speed up their production latencies when initial consonant and vowel (CV) of a target word were known in advance but failed to do so when the vowel was unknown. In Experiment 2, prior knowledge of the consonant and glide (Cj) produced no significant priming effect. However, in Experiment 3, significant effects were found for the consonant-vowel coupled with a nasal coda (CVN) and the consonant with a diphthong (CVV), compared with the consonant-vowel alone (CV). These results suggest that the implicit priming effects for Japanese are closely related to the CV-C and CV-V structure, called the mora. The authors discuss cross-linguistic differences in the phonological representation involved in phonological encoding, within current theories of word production.

Surface dyslexia in a Japanese patient with semantic dementia: evidence for similarity-based orthography-to-phonology translation.

We studied the reading performance of a Japanese-speaking patient, TI, with bilateral but asymmetrical (left more than right) temporal-lobe atrophy, severe anomia, and poor word comprehension. Most Japanese kanji characters correspond to several different legitimate pronunciations in different contexts, with varying degrees of correspondence consistency. TI made many errors in reading aloud words that violate statistically typical character-sound correspondences, especially for less common words, but had relatively preserved ability to read aloud strings in which the assignment of the typical pronunciation for each component character yields the correct pronunciation for the whole word. The degree of consistency of character-sound correspondences affected his performance on both words and nonwords in a graded manner. One interpretation is that TIs surface dyslexic reading reflects intact direct computation of phonology from orthography, but without the additional constraint from word meaning that is, in this framework, considered critical for correct pronunciation of lower-frequency words with atypical character-sound correspondences. Another interpretation is that TIs performance reflects partially damaged lexical knowledge of whole-word orthography and phonology, coupled with spared sublexcal knowledge of character-sound correspondence rules. Whichever of these interpretations is preferred, this study offers the most detailed information yet available on the characteristics of surface dyslexia in Japanese.

Verb Generation in Japanese—A Multicenter PET Activation Study

Cerebral blood flow (CBF) during silent verb generation was measured at four Japanese PET centers. To minimize the variance of the measurement, speakers of a single language (Japanese) served as subjects and experimental conditions at the four PET centers were controlled as much as possible. Two types of activation patterns were observed: activations in the left dorsolateral prefrontal cortices and the medial frontal cortex (at the two centers with a 2D PET scanner) and additional activation in the left posterior temporal cortex (at the two centers with a 3D scanner). This suggests either a difference in the sensitivity of the two types of PET scanners (viz., a 3D scanner is generally more sensitive than a 2D scanner) and/or subject bias due to the small number of subjects at the individual centers. The pooled activation pattern was fundamentally similar to activation patterns obtained in the previous studies for verb generation in English and other European languages, suggesting that regions for verb generation are independent of particular languages. Regions relevant to verb generation are discussed.

Deep dyslexia for kanji and phonological dyslexia for kana: Different manifestations from a common source

A Japanese-speaking stroke patient with disrupted phonology but relatively good semantics was severely impaired in nonword reading, with better preserved and imageability-modulated word-reading in both kanji and kana. This basic similarity of reading in the two Japanese scripts was accompanied by the following differences: (i) distinct error patterns (prominent semantic errors for kanji vs. phonological errors for kana); (ii) a more pronounced imageability effect for kanji; and (iii) a remarkable pseudohomophone advantage for kana. The combination of deep dyslexia for kanji and phonological dyslexia for kana in a single patient suggests that these are not two distinct reading disorders.

Organisation of language in the brain: does it matter what language you speak?

Abstract Brain disease or injury is a terrible thing, but the fact that the same kinds of brain diseases occur the world over offers researchers the opportunity to address the question posed by the title to this review. In the research described here, we assessed the reading skills of adult neurological patients (who had been normal speakers and readers prior to the onset of their brain damage) in both England and Japan. We chose patients in the two countries with the same causes and neuroanatomical locations of brain damage. The writing systems of English and Japanese differ fundamentally in the manner in which written words represent the sounds and meanings of the words in their respective languages. If the organisation of language in a persons brain is determined by the characteristics of the language he or she has learned, it follows that there should be little or no commonality in the patterns of reading deficit across these two languages. On the other hand, if the same principles of brain organisation apply across different cultures and languages, then we should be able to predict the nature of the reading impairments from one language to another when the same part of the brain is malfunctioning. The results discussed strongly suggest that the brains organisation of language is in fact the same no matter which language you speak.

The Eye Movements of Japanese Pure Alexic Patients During Single Word and Nonword Reading

Abstract Two Japanese patients with pure alexia, SH and YH, who showed right homonymous hemianopia following a left occipital lobe lesion, demonstrated letter-by-letter (LBL) reading in pronouncing Japanese kana words and nonwords. In contrast to alphabetic letters, each Japanese kana character has an invariant and identical pronunciation whether it appears in isolation or as a component of any word and nonword string. It is important to investigate the eye movements as well as reading latency and duration in Japanese-speaking LBL readers. Relative to normal controls, these patients demonstrated a more robust string-length effect, which was characterized by larger increases in reading latency and duration as well as in the number of fixations as the string length increased. We propose that in pure alexia, parallel activation of orthographic representations is abnormally delayed but not completely abolished.