Neurocase, 2015 Vol. 21, No. 3, 279–288, http://dx.doi.org/10.1080/13554794.2014.892621

Characteristics of dyslexia and dysgraphia in a Chinese patient with semantic dementia Xiao-qin Wua, Xiao-jia Liua*, Zhao-chun Sunb, Lindsay Chromikc and Ya-wei Zhangd a Department of Neurology, Southern Medical University of Nanfang Hospital, Guangzhou, PR China; bDepartment of Linguistics, Guangdong University of Foreign Studies, Guangzhou, PR China; cDepartment of Psychiatry and Behavioral Sciences, Center for Interdisciplinary Brain Sciences Research, School of Medicine, Stanford University, Stanford, CA, USA; dDepartment of Endocrinology, Southern Medical University of The People’s Hospital of Pingxiang, Jiangxi, PR China

(Received 12 May 2013; accepted 28 January 2014) We describe a 44-year-old Chinese-speaking patient with semantic dementia (SD), who demonstrates dyslexia and dysgraphia. The man was administered a series of neuropsychological inspections, including general language tests and reading and writing examinations. The patient demonstrated surface dyslexia when reading single Chinese characters aloud. While most writing errors demonstrated by the patient were orthographically similar errors and noncharacter responses, such as pictograph, logographeme, and stroke errors, rather than phonologically plausible errors that were homophonous or different only in tone from the targets. We suggest that the type of acquired dysgraphia demonstrated by Chinese-speaking SD patients is determined by the unique features of the Chinese writing system. Keywords: semantic dementia; dyslexia; dysgraphia; Chinese characters

Semantic dementia (SD) is a neurodegenerative disease characterized by the gradual deterioration of semantic memory and asymmetric atrophy of the anterior and lateral temporal regions (Hodges, Patterson, Oxbury, Funnell, 1992; Snowden, Goulding, & Neary, 1989; Warrington, 1975). It is understood that loss of semantic memory may result in an impoverished storage of general knowledge, vague conceptualization of items and ideas, and poor comprehension of single words. In the first several years of the disease, SD patients demonstrate obvious progressive aphasia, whereas other cognitive and behavioral functions remain relatively preserved (Kazui & Takeda, 2011). To understand language impairments in Chinesespeaking SD patients, it is essential to introduce the features of Chinese writing script. In mainland China, Putonghua is spoken universally. The Chinese writing system is considered logographic. Each character (e.g., 爸, father) maps to a syllable of sound (/ba4/). Number assigned to syllables represents tone mark. There are four tone marks, “1” for the high tone, “2” for the rising tone, “3” for the falling–rising tone, and “4” for the falling tone. Unlike alphabetic scripts, where phonemes are associated with letters, some scholars hold no phoneme corresponds to any target grapheme (Law & Or, 2001; Siok, Perfetti, Jin, & Tan, 2004; Weekes, Chen, & Gang, 1997; Yin, He, & Weekes, 2005). In other words, the visual–sound-correspondence that resembles the grapheme to phoneme conversion (GPC) used in alphabetic scripts doesn’t exist in

Putonghua, though some scholars may disagree with this assertion. In addition, homophones are very common. It is said that a syllable maps to an average of 15 homophonic characters on average (i.e., characters that have identical pronunciations but different meanings) (Standards Press of China, 1994). The structure of the Modern Chinese characters can be differentiated as either simple or compound. Simple characters are made up of spatial arrangements of strokes, which can combine to form logographemes (constituents) /radicals. The logographemes may be combined to create compound characters. A logographeme, a term coined by Law (also called a constituent) (Law & Leung, 2000), is the smallest unit in a character that is spatially separated. For example, the three parts (钅, 几, and 口) in 铅 are spatially separate from each other and are thus regarded as three different logographemes. Simple characters like 木 (wood)/mu4/ make up about 5% of the total characters in Modern Chinese and compound characters constitute about 95% of all Chinese characters (Yin & Rohsenow, 1994). Note that a small portion of simple Chinese characters are pictographic and represent a concrete object (e.g., 伞 (umbrella) /san3/). Of all compound characters, 84% of characters are so-called phonetic compounds, which contain a semantic radical and a phonetic radical (Yin & Rohsenow, 1994). The semantic radical, somewhat comparable to morphemes (e.g., “un-”) in English, indicates the meaning of the character, while the phonetic radical indicates how the character is pronounced

*Corresponding author. Email: [email protected] Present affiliation for Xiao-qin Wu is Department of Endocrinology, Southern Medical University of The People’s Hospital of Pingxiang, Jiangxi, PR China © 2014 Taylor & Francis

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(e.g., the composite character “清 (clear) /qing1/” is composed of two parts: the semantic radical “氵 (a logographeme)”on the left, meaning water, and the phonetic radical “青 /qing1/ (a radical composed by two logographemes)” on the right, meaning cyan). Upon examination, only 36% of phonetic radicals completely represent the characters’ sound, and 48% of them only partially represent the sound (Yin, 1991). Sixteen percent of compound characters are called associative compounds, whose forms indicate only meaning rather than pronunciation. In previous studies, two variables – regularity and consistency – were used to describe how reliably the pronunciation of a compound character can be predicted by the sound of its phonetic radical. If a character component has the same pronunciation as that of the character, then the whole character is considered regular; if not, the whole character is considered irregular (Weekes & Chen, 1999). A character is considered consistent only when it is a homophone with its phonetic radical and when all characters containing the same phonetic radical are also homophones (Bi, Han, Weekes, & Shu, 2007). For example, the radical “青/ qing1/” has the derivative “清 (clear) /qing1/” that is regular–inconsistent and has the derivative “猜 (guess) /cai1/” that is irregular–inconsistent. Mispronouncing the irregular compounds “猜/cai1/” as “青/qing1/” is considered to be a regularization error. Considerable evidence shows that reading ability is impaired in SD patients using alphabetic languages. Generally, patients with SD show a pattern of reading deficit named surface dyslexia (Funnell, 1996; Graham, Patterson, & Hodges, 2000; McKay, Castles, Davis, & Savage, 2007; Parkin, 1993; Patterson, 2007; Woollams, Ralph, Plaut, & Patterson, 2007). This pattern has difficulties in reading irregular words aloud, while relatively intact on regular words. For alphabetic writing systems like English, the theory of dual-route modeling has been suggested to interpret the performance of SD patients with

(a)

Figure 1.

acquired dyslexia (Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001). The framework of the information processing model in alphabetic language is depicted in Figure 1a. According to the model, two distinct but interactive procedures, which are referred to as the lexical (semantic and nonsemantic) and nonlexical routes, are used in processing written language. The lexical route allows reading of whole words which are stored in the input lexicon and the nonlexical route (orthographic-phonemic conversion (OPC)) allows accurate reading of regular words and unknown regular words like “plunt”. For irregular words like “pint”, OPC generates a regularization error. While there is no GPC rule in nonalphabetic scripts, typical regularization error, a critical feature of surface dyslexia, has been demonstrated. Researchers call this error as Legitimate Alternative Reading of Components (LARC), in which the new pronunciation of the component is inappropriate for the target word, but is nonetheless a legitimate and more typical pronunciation (Patterson, Suzuki, Wydell, & Sasanuma, 1995). In Chinese, if the character “猜/cai1/” is read aloud as /qing1/, a LARC error is being committed. Several studies on the features of reading in nonalphabetic SD patients have been conducted in Japanese and Korean languages (Fushimi, Komori, Ikeda, Lambon Ralph, & Patterson, 2009; Fushimi, Komori, Ikeda, Patterson, Ijuin, & Tanabe, 2003; Nakamura et al., 2000; Patterson et al., 1995; Suh et al., 2010). Japanese and Korean languages incorporate two different types of writing systems, phonographic Kana and logographic kanji for Japanese word, and Hanja (ideogram, Chinese letters) and Hangul (phonogram, Korean letters) for Korean words. All Japanese patients demonstrated impaired oral reading of logographic kanji characters and demonstrated a pattern of surface dyslexia on tests of reading, while oral reading of phonographic Kana was unaffected. Oral reading of lower-frequency kanji words with atypical orthography to phoneme mapping was most

(b)

(a) A functional model of reading in alphabetic languages. (b) A functional model of reading in Chinese.

Neurocase impaired and provided evidence for “character–sound correspondences”, which was similar to orthography to phonology translation (Fushimi et al., 2003, 2009). Korean SD patients show Hanja (ideogram, Chinese letters) alexia, whereas Hangul (phonogram, Korean letters) reading ability is well preserved (Suh et al., 2010). Although Guo and Zhang mentioned impaired reading in Chinese SD patients, yet a detailed study has not been reported (Guo, Hong, Fu, Yu, & Lu, 2003; Zhang et al., 2008). It has been suggested that the reading in Chinese always relies on the lexical route because there is no GPC rule (Law & Or, 2001; Law, Wong, & Chiu, 2005; Weekes et al., 1997; Yin et al., 2005). Weekes hypothesized a lexical processing model for normal oral reading of Chinese script from print to phonological output. As is shown in Figure 1b (Weekes et al., 1997), the model assumes a lexical semantic procedure, which allows reading for meaning, and a lexically mediated nonsemantic procedure, which directly connects all orthographic representations (i.e., strokes, radicals, and characters) to all phonological representations (i.e., syllables, rhymes, and tones). On the basis of this model, Weekes predicted that surface dyslexia is attributable to selective damage to the lexical semantic pathway, causing LARC errors in reading. Less research has been published on writing than on reading. Several papers report spelling impairment in SD patients, but systematic studies to support this finding are still lacking. Graham presented the first detailed study of spelling and made a fine-grained analysis of spelling performance using formal and strict writing-to-dictation, which is often considered as the counterpart of reading in 14 SD patients whose native language had an alphabetic-writing system (Graham et al., 2000). He found that SD patients were better at spelling regular sound-to-spelling corresponding words than irregular words, and most errors were phonologically plausible renderings of the target words (i.e., phonologically plausible errors, PPEs), e.g., “flood”→ “flud”. This type of error is called surface dysgraphia. The dual-route model, mentioned above (Figure 1a) as a cognitive architecture of the information processing system, could also explain seven SD patients’ acquired dysgraphia, as the mapping between visual orthographic analysis and phoneme system is bidirectional (Rapcsak, Henry, Teague, Carnahan, & Beeson, 2007). In nonalphabetic writing systems like Chinese, Korean Hanja, and Japanese Kanji, detailed and systematic studies are absent. Suh found all SD patients had Hanja (ideogram), agraphia while their Hangul (phonogram) writing ability remained relatively preserved (Suh et al., 2010). Fushimi reported that a Japanese SD patient suffered from selective impairment in spelling with morphographic kanji characters, but intact dictation of phonographic kana characters (Fushimi et al., 2003). Some Chinese researchers proposed that with no phonology to orthography conversion (POC) correspondence, the model shown in Figure 1b can explain writing-to-dictation via a semantic

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and a lexically mediated nonsemantic pathway, if the mapping between orthography and phonology is supposed to be bidirectional (Law & Or, 2001; Reich, Chou, & Patterson, 2003; Yin et al., 2005). Theoretically, a damaged nonsemantic pathway cannot inhibit the semantically related writing responses generated by the lexical–semantic pathway, and a damaged lexical–semantic pathway cannot inhibit the phonologically plausible responses (i.e., homophonic) generated by the nonsemantic pathway. Then what performances does a Chinese-speaking SD patient have in reading and writing, including whether errors are similar to SD patients who speak English and whether the above models are useful in understanding the errors made.

Case report Subject L, a right-handed 44-year-old man with 12 years of education, was a bank clerk. During the Spring Festival, in February 2011, distant relatives found his reaction time was slow during card games and that he spoke less and appeared to struggle to find words. From then on, Mrs. L often observed him making mistakes when speaking. L appeared to be unaware of these mistakes. Due to these concerns, Mrs. L accompanied Mr. L to visit Nanfang Hospital, the Southern Medical University, Guangzhou. L complained of being unable to comprehend what others said when making phone calls, as well as being unable to understand what he read in a newspaper or heard on television. No deterioration was observed in episodic memory and self-care. He was able to complete simple daily tasks of living, but was no longer able to work and struggled to have discussions about things such as the news. At the end of April 2011, general cerebral magnetic resonance imaging (MRI) (Figure 2a) showed circumscribed atrophy in the left temporal and bilateral frontal lobes. In the early May of 2011, a SPECT (single photon emission computed tomography) scan (Figure 2b) revealed cortical thinning of the left lateral temporal lobe and the inferior cortex presented hypoperfusion. Positron emission tomography (PET) maps displayed reduced metabolism in the bilateral frontal, left partial temporal, and parietal lobes (Figure 2c) in mid-May of 2011. L had no history of drug and alcohol abuse, cerebral trauma, stroke, or other significant disease in the past. After his initial hospital visit, overall blood biochemistry examinations were performed and were normal. Therefore, dementia resulting from hypothyroidism, syphilis, and other diseases was excluded. The patient’s younger age and no sign of severe recent amnesia and visuo-spatial impairment also made Alzheimer’s Disease less likely. In addition, the behavioral variant of frontotemporal dementia and progressive nonfluent aphasia were not considered because of their

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Figure 2. Neuroimagings from L with SD. (a) T1-weighted MRI scans (the left temporal and bilateral frontal lobes). (b) SPECT scanning (the left lateral temporal lobe). (c) PET maps (the bilateral frontal, left partial temporal and parietal lobes). [To view this figure in color, please see the online version of this Journal.]

respective characteristics. The patient was diagnosed with SD based on both his clinical presentation and the neuroradiological findings. A series of neuropsychological assessments, mostly related to the function of language, were administered from June 5, 2011 to June 7, 2011. Four months later, L returned to the hospital presenting with a sharp decline in language comprehension and expression. Mrs. L complained that his poor language interfered with his daily life. L could no longer make purchases at stores, because he was unable to name the items he wanted and he could not comprehend what was said to him by salespeople. His daily living skills, including bathing, grooming, and using transportation, were still preserved.

Materials and procedure The Mini-Mental State Examination, Montreal Cognitive Assessment, Clinical Dementia Rating Scale, Wechsler Adult Intelligence Scale–Revised, and Wechsler Memory Scale–Revised were administered on June 5, 2011 after informed consent was obtained from Mr. L and his wife. General Language Tests, including the Aphasia Battery of Chinese (ABC) (Gao, 1996) and the Western Aphasia Battery (WAB) (Wang, 1997a, 1997b), each consisting of six main subsets assigned to evaluate spontaneous speech, comprehension of speaking, repetition, naming, reading, and writing, were administered to evaluate L’s language functioning on June 6, 2011. As his reading performance was intact, as measured by the ABC and WAB scales, no further tests were initially administered to assess his reading ability. However, on November 7, he presented with difficulty in reading simple items. In order to explore the type of alexia L demonstrated, a reading examination of Chinese characters developed by Jinan Medical College was administered (Wu & Lin, 1999). The examination has been demonstrated to have good reliability and validity in

distinguishing between normal and abnormal readings in normal subjects and subjects with dyslexia. We adopted a part of the reading examination consisting of 17 simple characters (nine phonetic radicals and eight semantic radicals), 33 component inconsistent characters (9 regular– inconsistent and 24 irregular–inconsistent), and 10 “readable” pseudo-words (semantic and phonetic radicals were combined together in legal positions to create pseudowords, e.g., “木 (wood) /mu4/” as a signific on the left and “青 (blue) /qing1/” as a phonetics on the right). Each real character selected from the General Characters List of Modern Chinese is common to daily life. The average word frequency is 0.1676 ± 0.5493 and the average frequency of utilization is 14282.1 ± 51345.2. A total of 60 characters (both real and pseudo) on cards were randomly placed in a stack. The subject was required to read the cards aloud, explain its meaning by gestures and by making up a phrase or a sentence with the character he had just read, and finally he was asked to choose the correct picture from four options. The cards showing phonetic radicals are not for option because they are not matched to pictures as these characters typically convey no meaning. The distracters might be pictures corresponding to semantic radicals or phonetic radicals, pictures corresponding to characters similar in shape or pronunciation to target characters, or semantically irrelevant pictures. Take the character “晴 (sunshine)”, for example, the similar shape of it is “睛 (eye)”, thus, one of the distracters is a picture of an eye. The ABC, coupled with the Chinese agraphia battery (CAB) (Liu, Liang, Lu, Li, & Lin, 1996), was administered to L and a healthy control matched for education, age, and gender. The CAB includes (1) spontaneous writing of digits, (2) direct copying of written words (semantic radicals, two-character words, and sentences), (3) writing-todictation (semantic radicals, digits, single-character, twocharacter words, and short sentences), (4) writing-to-

Neurocase pictures (semantic radicals adding, written word naming of objects/color/geometric shapes/actions, and written sentences), and (5) writing sentences to convey meaning. These tasks were administrated on June 7 and again on November 7 to track changes in his writing performance. Given the existence of homophony at the level of monosyllabic words in the Chinese writing system, all dictation tasks used a word context (two-character words) so that the meaning of the particular character being dictated was clear. All assessments were administered according to standardized protocol in a quiet neuropsychological assessment room. The normal control completed the special reading and writing tasks.

Results L scored 20 on the Mini-Mental State Examination, 19 on the Montreal Cognitive Assessment, and 1 on the Clinical Dementia Rating Scale, indicating probable dementia. Missing scores were mainly in execution, language, and abstract thinking. His intelligence was in the below average range on the Chinese version of the Wechsler Adult Intelligence Scale–Revised. He exhibited more marked deterioration in verbal IQ than performance IQ. Due to his verbal deficit, he performed poorly on information, vocabulary, comprehension, and similarities subsets, with raw scores of 3, 1, 0, and 0, respectively. On the nonverbal assessments, he had raw scores of 7, 5, 4, 4, and 4 on digit span, picture completion, block design, object assembly, and picture arrangement, respectively. On the Wechsler Memory Scale–Revised, he demonstrated a marked comprehensive Table 1.

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and visual memory discrepancy. His logical memory raw score was 1.5, while his design memory raw score was 11 and his memory recognition raw score was 14. L’s Aphasia Quotient (AQ) on the WAB was 67.6 on June 6, but dropped dramatically to 35.4 on November 7. Table 1 shows his performance on subsets of the ABC and WAB. It is noteworthy that his score on the object-naming subset of the WAB was 51/60 on June 6, 2011, but 4 months later, he received a score of 12/60. Half of L’s November responses to 20 different objects from the naming subset of the WAB were either “火柴 (match) /huo3chai2/” or “铅笔 (pencil) /qian1bi3/”. The majority of the remaining errors were semantic coordinate errors. The testing performed in November revealed deteriorated performance on almost all subsets. However, L had nearperfect performance on the repetition subset both for single words and short sentences. On the ABC, he initially performed highly on spoken word–picture matching (50/ 50), a measure of word recognition, and committed only one error on written word–picture matching (19/20). All materials in word–picture matching subsets are of extremely high familiarity, rendering them insensitive to mild degrees of semantic impairment. However, in November, his scores on these two tasks predictably declined, with performances of 20/50 and 8/20, respectively. Mr. L showed severe anomia and poor comprehension of sentences and commands, typical characteristics of patients with SD. Therefore, these results suggest a rapid decline in semantic processing. Woollams claimed that anomia is a defining feature of SD (Woollams, Cooper-Pye, Hodges, & Patterson, 2008). Thus, the patient’s presence of a mild

L’s scores on subsets of WAB and ABC.

Language production Scene description (WAB) Speech fluency (WAB) Object naming (WAB) Semantic fluency (animals within 1min in WAB) Semantic fluency (vegetables within 1min in ABC) Word repetition (WAB) (ABC) Sentence repetition (WAB) (ABC) Reading aloud irregular words Language comprehension Word comprehension (WAB) (ABC) Sequential commands (WAB) (ABC) Lexical decision task (ABC) Written word-to-picture (ABC) Written command comprehension (ABC) Black filling (WAB) (ABC)

June 2011

November 2011

Total Possible

9 6 51 4 2 34 24 40 61 9

5 4 12 0 0 32 24 28 11 3

10 9 60

37 74 19 14 7 19 6 14 4

22 38 2 6 3 8 1 6 2

60 90 80 80 10 20 10 40 30

Note: WAB, The Western Aphasia Battery; ABC, The Aphasia Battery of Chinese.

34 24 66 76 10

284 Table 2.

X.-Q. Wu et al. Analysis of responses in the reading task in November 2011.

Chinese character classification Phonetic radicals Semantic radicals

Regular characters Irregular characters

Print characters Example Example Example Example Example Example Example Example Example Example Example Example Example Example

1 青/qing1/ cyan 2 勺/shao2/ spoon 3 木/mu4/ wood 4 贝/bei4/ shell 5 目/mu4/ eye 6 睬/cai3/ pay attention to 7 沟/gou1/ gully 8 鞋/xie2/ shoe 9 海/hai3/ ocean 10 猜/cai1/ guess 11 菜/cai4/ vegetable 12 豹/bao4/ leopard 13 旱/han4/ drought 14 池/chi2/ pond

naming impairment in June tells us that the patient was in an early stage of the disease at the time of his first assessment. On error analysis of the reading task, Mr. L read aloud 17/50 (34%) Chinese characters incorrectly. See Table 2. He produced two errors in reading aloud phonetic and semantic radicals. One was phonetic radical “勺 (spoon) /shao2/” – example 2, which was mispronounced in line with a similar shape “勾 (hook) /gou1/” and the other was failing to respond for semantic radical “目 (eye) /mu4/” – example 5. The subject made 15/33 (45.45%) errors when reading compounds, of which 0/9 (0%) were regular characters and 15/24 (62.5%) were irregular characters. It showed that L performed substantially better at reading regular characters, as opposed to irregular characters. He was prone to read high-frequency irregular characters like “鞋 (shoe)/xie2/” – example 8 accurately, while he typically failed to do so with low-frequency characters like “豹 (leopard)/bao4/” – example 12. Distribution of remaining errors of the irregular characters was categorized as follows. The first main category was LARC errors (10/24, 41.67%), e.g., “猜 (guess) /cai1/”→“青 (blue) /qing1/” – example 10, and “菜 (vegetable) /cai4/”→“采 (pick) /cai3/” – example 11. The second category of errors was visually related errors, meaning the output corresponded to a character that was orthographically similar to the target, e.g., “旱 (drought) /han4/”→“早 (morning) /zao3” – example 13. He made 4/24 (16.67%) errors of the second category. The remaining error was nonresponse (1/ 24, 4.17%): “池 (pool) /chi2/” – example 14. Two irregular characters which require additional explanation are “豹 (leopard) /bao4/” – example 12 and “钓 (fish) /diao4/”. L misread both as “/gou1/”. As previously mentioned, he mispronounced the phonetic radical character “勺 (spoon) /shao2/” as “勾 (hook) /gou1/”. Thus, we interpreted them as the LARC of the irregular characters and assigned them to the first error category. The classification

Phonology output

Response of matching picture

/qing1/→right /gou1/→wrong /mu4/→right /bei4/→right say don’t know /cai3/→right /gou1/→right /xie2/→right /hai3/→right /qing1/→wrong /cai3/→wrong /gou1/→wrong /zao3/→wrong Say don’t know

Right Wrong Right Wrong Wrong Right Wrong Right Wrong Right Right Wrong Wrong Wrong

of all kinds of production on the reading task is illustrated in Table 2. Although the irregular characters in this reading task are very common in daily life, he made 62.5% errors, of which LARC errors constituted the largest proportion. For the pronounceable nonexisting characters, he was able to read aloud all of them quickly, based on the phonetic radical instead of recognizing that they were not real characters. In summary, our patient exhibited typical features of surface dyslexia. Due to severe semantic deficit, L was only able to generate sentences to explain the meaning of two of the characters he was presented. He made 25/41 errors (61% incorrect) in matching characters with the appropriate pictures. More than half of his incorrect choices were pictures corresponding to phonetic radicals (9/25) and semantic radicals (4/25). Nine of 25 errors were semantically unrelated pictures and three were pictures of items phonologically similar to the target characters. For 14 of the 18 characters that he read correctly, the patient couldn’t choose the correct pictures. This suggests that the patient was able to read characters correctly without comprehending the meaning. For instance, he could read aloud “海 (ocean)/hai3/” – example 9 correctly, but selected a semantically irrelevant picture. From his 10 pseudo-character tasks, we found that he selected eight pictures relevant to the shape of the characters. The control was able to read aloud all real characters, explain their meanings correctly, and match them to the pictures successfully. As for 10 pseudo-characters, he pointed out that 9 of them does not exist except one which he also read aloud using its phonetic radical. On analysis of the writing tasks, it was found that L’s performance was substantially poorer compared to reading tasks. His scores on the CAB on June 7 were: writing-topictures (6/40, 15% correct), writing sentences to convey meaning (2/10, 20% correct), writing-to-dictation (11/40, 27.5% correct), writing his own name, age, and address (9/ 10, 90% correct), spontaneous writing from 1 to 23 (19/20,

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Figure 3. L’s direct copying performances on June 7, 2011 (the second line) and November 7, 2011 (the third line, with erroneous characters squared). The first line is the target. Note: A, semantic radicals. B, two-character words (paraphrases: idea/ reunion/far and near/ sun and moon). C, sentence (paraphrase: Beijing is the capital of China).

95% correct), and direct copying (40/40, 100% correct). During the copying task, the patient correctly produced all written characters with the appropriate order of strokes. Four months later, he made repetition, insertion, and deletion errors when performing the spontaneous number task (9/20, 45% correct). The kinds of errors seen in direct copying are illustrated in Figure 3. Logographeme errors and stroke errors are easily identifiable. For instance, target logographemes or strokes were deleted, added, substituted, and transposed, thus resulting in the creation of other existing characters or noncharacters. His performance on direct copying in November declined (32/40, 80% correct) from his previous performance. His scores on other

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subsets also declined, with scores of 0, 2, and 2 in writing sentences, writing-to-pictures, and writing-to-dictation, respectively. He demonstrated extremely poor writing ability at the second testing. His writing included a large number of repeated characters, noncharacters, and nonresponses. He presented with agraphia with significant presence of noncharacter responses, incorrect character responses, and impaired grammatical abilities. We classified his writing errors as follows: (1) The noncharacter responses were divided into pictograph errors, logographeme errors, stroke errors, and combinations of logographeme and stroke errors. (2) The incorrect character responses referred to characters that were not the target character, but were real characters in the Modern Chinese dictionary. This error type comprised PPEs (the response is orthographically dissimilar to the target, but is homophonous or differed only in tone from the target), in which L made 4 mistakes out of 34 Chinese characters in the writing-to-dictation task (i.e., “童 (child)/tong2/”→“同 (like) /tong2/), orthographically similar errors (the output and the target have one or more character constituents in common), semantic errors, and unrelated errors. (3) The grammatical impairments (e.g., chaotic sequence) were manifested in subsets involving writing sentences based on pictures and spontaneous writing. Table 3 shows some specific examples of error analysis of writing. Each subset,

Table 3. Some specific samples of errors in the written task. Because there are so many Chinese characters in this table, thus using a pure Microsoft Word to make it is very difficult. We guarantee it is an original work. Written subtests

Writing-to-dictation

Writing-to-pictures

Writing sentences to convey meaning

Noncharacter responses

Miswriting character responses

Grammatical impairments

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except the copying task, contained many characters, of which the patient could not produce any part, especially at the second testing. Nonresponses were the most common type of errors on the second administration. His scores on the CAB on November 7 were: writing sentences to convey meaning (0/10, 0% correct), writing-topictures (2/40, 5% correct), writing-to-dictation (2/40, 5% correct), spontaneous writing from 1 to 23 (9/20, 45% correct), writing his own name, age, and address (5/10, 50% correct), and direct copying (33/40, 82.5% correct). He failed to dictate semantic radicals correctly both in June and November. He also made mistakes when dictating digits (42→24, 1860→100080). By contrast, the control had no difficulty on all writing tasks. Discussion The aim of this study was to explore reading and writing impairments in an SD patient whose native language is Chinese, a nonalphabetic script. The performance of L on reading aloud regular–inconsistent characters (100%) was superior to his reading of irregular–inconsistent characters (37.5%). Pseudo-characters were all read aloud according to the pronunciations of phonetic radicals. He was prone to making LARC errors and could orally pronounce 100% of the pseudocharacters, a typical feature of surface dyslexia in reading. This is in line with results from studies on Japanese-speaking SD patients (Fushimi et al., 2003, 2009). Yin first reported an association between the production of LARC errors and semantic impairment when reading irregular characters (Yin & Butterworth, 1992). He reasoned that lexical–semantic knowledge might impact the ability to read irregular characters. Weekes presented a hypothesis that correct reading of low-familiarity, abstract Chinese characters requires support from semantic memory, and damage to the lexical–semantic pathway would result in LARC errors (Weekes & Chen, 1999). Through induction and summarizing previous literatures, Yin insisted that in the absence of sufficient semantic knowledge, more common pronunciations of components would dominate computation of phonology from orthography through the lexically mediated nonsemantic pathway (Yin et al., 2005). That is to say, it is plausible that when a component character is read, its pronunciation competes with the phonetic component. Because the latter’s frequency of occurrence is usually higher than that of the phonogram, activation of the pronunciation of the phonetic component is easier than that of character (Zhou & Marslen-Wilson, 1999). For example, “干 (dry)” is a phonetic radical and “杆 (stick), 竿 (stick), and 汗 (sweat)” are all its derivatives. Thus, it is easier to settle on the phonetic radical’s pronunciation than the pronunciation of the target. Because of this, irregular words may be incorrectly pronounced according to the phonetic radical. There is no

competition between component character and phonetic radical in regular words (Luo, Zhao, Wang, Xu, & Weng, 2007). These ideas are based on the classic theory, according to Figure 1b conveying an assumption that the nature of surface dyslexia in reading Chinese may not be the same as in alphabetic reading. Above all, damaged semantic memory processing is closely related to surface dyslexia, which is a known feature of SD in Japanese- and English-speaking patients and which the patient in our study also demonstrated. The patient’s assessment results indicate that the semantic route was not functioning properly. This requires the existence of a direct lexical nonsemantic pathway linking the orthographic lexicon and the phonological lexicon, while bypassing the semantic system to account for his pattern of responses. L demonstrated typical Chinese agraphia resulting from impaired language functioning. As shown in Figure 3, the patient’s copying ability was initially unaffected. His writing conformed to normal stroke order. This suggests that literacy in Chinese allows for the retention of procedural memory of stroke extraction in the early stage of SD. In addition, in spite of the patient’s impaired copying ability during later testing, he still produced figures that maintained the overall configuration of the target with some altered strokes or components. Character skeleton was also retained in other parts of the writing. For example, for the target “间 (room) /jian1/” or “采 (pick)/cai3/”, L would produce similar-shaped characters like “问 (ask) /wen4/” with the same semi-surrounded configuration or “伞 (umbrella) /san3/” with the same top-bottom configuration. This can be explained by the fact that the focus lesion selectively damages identity information on some of the constituents while leaving structural information intact (Law, 2004). For example, if the information about a constituent cannot be accessed, language network may fill the gap using another constituent. In this way, the overall makeup of the character is preserved. As the disease progresses, impairments in writing ability become more global. This deterioration affects not only complicated tasks, such as diction, but also simpler tasks such as copying. A comparison (Figure 3) of L’s copying productions at two different time points shows that the procedural memory of stroke extraction was affected in the later stage of SD. L made 4 PPEs out of 34 Chinese characters in the writing-to-dictation task. His PPEs are similar, though not identical, to the pattern of surface dysgraphic errors produced by the phoneme to grapheme conversion rules when spelling irregular characters in SD patients who speak alphabetic languages. The appearance of orthographic output homophonic with the target in writing-to-dictation supports the Chinese cognitive framework mentioned above (Figure 1b), supporting the evidence that this type of error is associated with a preserved lexically mediated nonsemantic pathway (Law & Leung, 2000; Law & Or,

Neurocase 2001; Yin et al., 2005). With impairment in the lexical– semantic pathway, there is not a sufficient constraint on the production of those homophonic responses. Writing-todictation, the process of producing orthographic output when given a sound, is often viewed as the counterpart of reading. Our patient made more orthographically similar errors and noncharacter responses such as pictograph, logographeme, or stroke errors. In contrast, when spelling of words with exceptional sound-to-spelling correspondences, SD patients from alphabetic-writing systems also committed errors, but most were PPE (e.g., “flood”→ “flud”) (Graham et al., 2000). The type and distribution of errors on writing tests differ for Chinese SD patients and other SD patients from alphabetic-writing systems. Possibly, this difference can be attributed to the nature of the two writing systems as follows: (1) The logographic system maps graphic forms (characters) onto morphemes (meanings) and the phonological system serves as a mark used for subsidiary of learning Chinese characters, as opposed to the alphabetic writing system, whose morphological structures of words are linear strings of letters that independently convey no meaning and whose spelling relies on pronunciation and the mapping of phonemes onto graphemes. Actually, in ancient times, there was no pinyin. With the development of society, the phonological/ pinyin system used for the phonetic transcript of Chinese characters has been adopted gradually, but it was not widespread in the last few decades. It is a fact that quite a few elder Chinese people can write the target character correctly but was not able to produce corresponding Chinese phonetic alphabet (pinyin). Thus, we see that the recognition and memory of the orthographic representations are particularly important during character learning, while the phonological system plays the role just as a kind of auxiliary tool. That is why SD patients from alphabeticwriting systems committed most PPEs, while Chinese SD patients committed more orthographically similar errors, logographeme, or stroke errors; and (2) Many of the ancient Chinese characters were pictographic, which means the written character portrayed the form of the object it symbolized and a small part of these characters are still used today. So it is not strange that our patient made some pictograph errors like “伞 (umbrella)”. See Table 3. In summary, this is a preliminary study of SD in Chinese patients and is primarily descriptive in nature. Further studies should be done with larger sample sizes so that statistical analyses may be performed.

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