Since I started working in the field of brain injury rehabilitation twenty seven years ago I have noticed several developments and these are almost certainly for the better. Not all are new developments as Poppelreuter was describing some of them as long ago as 1917. Indeed, the rehabilitation programmes set up for the German soldiers who survived gun shot wounds to the head in the first world war are better than many rehabilitation programmes in existence today. Nevertheless, the early twenty first century is an exciting time to be working in rehabilitation and the future looks promising. To my mind, the most important and influential developments in the past decade are those I list below.
     1. Rehabilitation is now seen as a partnership between people with brain injury, their families and health service staff.
     2. Goal planning is becoming increasingly established as one of the major methods for designing rehabilitation programmes.
     3. Cognitive, emotional and psychosocial deficits are interlinked and all should be addressed in neuropsychological treatment programmes.
     4. Technology is playing (and will continue to play) an increasing part in the understanding of brain injury and in enabling brain injured people to compensate for their difficulties.
     5. Rehabilitation is beginning to take place in intensive care, it is not solely for those people who are medically stable.
     6. There is a growing belief that neuropsychological rehabilitation is a field that needs a broad theoretical base incorporating frameworks, models and methodologies from a number of different fields.

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  Traditional view of language hypothesizes two distinct mechanisms, the mental grammar and lexicon. In pasttense generation of English regular verbs, for instnace, morpheme ⁄-t⁄, ⁄-d⁄ or ⁄-Id⁄ is added to the verb stem depending on the word final consonant (e.g., ⁄luk⁄-⁄lukt⁄). The same is true for Japanese although it has dozens of verb inflectional endings. On the other hand, there are verbs to which rules are not applicable, viz., irregular verbs. For these rule-violating verbs the lexicon is referred to retrieve their past-tense forms(e.g., ⁄giv⁄-⁄geiv⁄). Damage to the grammar or lexicon is assumed to produce impairment in past-tense generation of regular or irregular verbs, respectively. Similarly, the traditional view hypothesizes the rule and lexicon in word reading aloud.
  Connectionist has a different view. They construct neural networks with phonological, semantic and orthographic layers but without the grammar and lexicon, and demonstrate that such a neural network can generate past-tense forms of both regular and irregular verbs. Disturbance in phonology or semantics produces deficit in past-tense inflection of regular or irregular verbs, respectively. It was shown that the network with a similar structure can read words with regular and irregular spellings.
  In this article, I will describe details of the two major neuropsychological theories, and how these work in Japanese verb inflection and word reading.

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  The ability to read or write is not biologically prepared but can be acquired only through instruction and adequate learning. Different neuronal networks may be organized according to the characteristics of different script systems. This cultural effect should be taken into account in order to analyze the symptoms of acquired dyslexia. Therefore, the theoretical framework of cognitive neuropsychology on reading disorders in Western language, as it stands, should not be applied to the symptomatology of acquired dyslexia in Japanese patients who employ unique writing systems. The most important difference between English and Japanese is the type of basic visual units in written language ; words in English vs letters in Japanese. The another striking feature is that Japanese speakers usually imagine letters when they communicate trough spoken language. Kana (syllabogram) letters represent abstract and highly categorized phonological symbols.
  Two patients with aphasic alexia were reported, who produced a large number of semantic paralexias in reading aloud Kana words, as well as in Kanji (morphogram) words. The examination of 4 phonological dyslexics led us to conclude that underlying factors responsible for the impairment of oral reading of Kana nonwords are a disturbance in literal-to-phonological transcoding and a disorder in sequential processing, in addition to a general phonological impairment. A patient with word meaning deafness who could understand orthographically unfamiliar Kana words was reported. A hypothesis is presented that the refinement of phonological representation, from lower level to higher one, is disrupted in word meaning deafness.

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  Issues concerning repetition, especially input processing and echoic memory, which is crucial for short-term verbal retention, were discussed from the psychophysiological standpoint. First, a cognitive neuropsychological model of input processing of repetition was shown. Based on the model, the author focused on the four levels of processing—word sound analysis, input phonological identification, input lexical identification and semantic decoding—and echoic memory. For each level, symptoms when typically disturbed and the underlying mechanisms thought to be behind the symptoms were discussed based on the clinical data. In addition, electroencephalographical methods for verifying the underlying mechanisms were suggested.

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  Writing and typing abilities of a 57-year-old, right-handed Japanese patient with aphasia due to cerebral infarction were investigated. Writing was comparatively preserved when the patient used kanji. In kana, however, he showed a salient deficit in writing a single kana and a non-existent, two-mola kana word to dictation even though a substantial number of kana words could be produced both spontaneously and to dictation. Similarly a number of phonetic values for kanji were written in kana correctly. Semantic paragraphias were observed in writing both kana and kanji words to dictation. Unsuitably selected phonetic values for kanji were also produced in kana without orthographic errors. It was suggested that his abilities to write kana were dependent on the semantic processor and that kinesthetic images of characters were recruited by way of the semantic-visuomorphographic-kinesthetic route and⁄or the semantic-kinesthetic route. Although writing single kana and Roman characters to dictation as well as reading them aloud showed poor performance, written conversion from kana to Roman characters and vice versa was preserved. Such written conversion was presumed to be processed within the visuomorphographic processor of characters. We concluded that the non-phonological kana writing system was based on the predominance of the semantic, visuomorphographic and kinesthetic processors rather than the route via the phonological processor. Furthermore, it was suggested that such non-phonological processors played an important role in his typing of Roman characters as well.

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  A case of aphasia with cognitive dysfunctions was studied with respect to the process of managing diabetes mellitus (DM) with self-injections of insulin. The patient, a 73-year-old, right-handed woman who had left her DM untreated for 10 years, suffered from a cerebral infarction immediately after an operation for aortic dissection. Self-management of DM was initiated three months after her stroke. Problems were poor understanding of her disease and severe communication disorder affiliated with higher brain dysfunctions including aphasia. Education concerning DM and technical guidance in insulin self-injections over a period of about one month resulted in her returning home with successful acquisition of insulin self-injection capability. This study indicates that in order to obtain independent management of insulin injections by patients with cognitive dysfunctions, medical treatment providers need to deal with patients according to their individual abilities relying on shared knowledge about higher brain dysfunctions.

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  Phonological dyslexia in Japanese-speaking patients has been described as a selective impairment of reading kana nonwords in contrast to preserved ability to read both kana words and kanji words. In the framework of the classical dual-route model, this dyslexic pattern is interpreted as arising from a disruption of the non-lexical route in which a kana string is converted to phonology based on kana-mora correspondence rules, coupled with the preserved lexical route for whole-word translation from orthography to phonology. To understand the mechanisms underlying phonological dyslexia, we conducted a series of experiments involving both reading and non-reading tasks in a right-handed 64-year-old Japanese female patient, AC, with moderate non-fluent aphasia after cerebro-vascular injury in the left insula, the frontal operculum, the precentral gyrus, the postcentral gyrus, and the supramarginal gyrus. In reading aloud kana strings, AC demonstrated good performance with real words and pseudohomophones but moderate difficulty with non-homophonic nonwords. In reading aloud kanji strings, she again showed preserved performance with real words but a disruption with nonwords. Among a variety of phonological tasks in which written materials were not employed, she exhibited marked impairment in mora deletion (e.g., donaki → naki) and mora reversal (e.g., kodohi → hidoko) of words and nonwords. In lexical decision tasks with spoken and kana stimuli, her accuracy deteriorated for kana strings when nonwords were similar to their word counterparts. In comprehension tasks with kanji words when they are presented in kanji, kana(hence pseudohomophones), or spoken forms, her score was significantly lower with kana than with kanji or a spoken form. These results indicate that phonological dyslexia is neither a selective impairment in reading aloud kana nonwords nor a selective disorder of reading aloud. The symptoms observed in AC are assumed to derive from a disruption of the phonological system in the dual-route cascaded model, or from an impairment in phonology in the triangle model.

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  A case with so-called discourse problem by Ponsford is reported.
  An unemployed man aged 37 yrs showed the characteristic symptoms besides attention disturbance, memory impairment, and executive dysfunction as sequelae of traumatic brain injury.
  The brain lesions were found in both dorsomedial part of prefrontal area, lateral part of right temporal lobe and right amygdale. The characteristic symptoms observed in this case are as follows : round-about speech ; unsuitable topics of conversation; disregard of unpleasantness of listeners. It appeared that his interpersonal relation ship disorder was attributable to the symptoms. We assumed that executive dysfunction, difficulty in perception of non-verbal message from others, and control loss of speech manner contributed to the symptoms.

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