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Background:The presence/absence of agrammatism is critical for the classification of the different subtypes of primary progressive aphasia (PPA). Its quantitative evaluation is, however, a challenge in clinical practice because there are few brief, reliable, and easy-to-administer tests. Linguistic analysis of connected speech is the gold standard but is impractical outside the research setting. Aims:To tackle the need for brief grammatical tests, we developed the SEntence Comprehension Test (with auditory and visual versions, SECT A and V) and the Make A Sentence Test (MAST). Methods & Procedures:The tests were given to 92 participants (41 PPA patients, 21 Alzheimer’s disease patients, and 30 controls) from the Cambridge Longitudinal Study of PPA. Classification of the different subtypes of PPA was made purely on clinical assessment to avoid circularity from using the tests for diagnostic purposes. In addition, speech samples were recorded during a face-to-face semi-structured interview and all participants completed a standard neuropsychological battery as well as the three new tests. Outcomes & Results:All patients were impaired relative to controls on the SECT A and V. After controlling for semantic impairment, only the mixed variant of PPA (mPPA) and the non-fluent variant of PPA were impaired on the MAST. When controlling for working memory in SECT A, the mPPA only remained impaired. Regression analyses demonstrated that performance on the SECT A and V, and the MAST, was strongly related to measures of the patients’ spontaneous speech, particularly the number of grammatical errors and the percentage of abandoned and elliptical sentences. Performance on the SECT A was also significantly predicted by speech rate. Conclusion:The SECT and the MAST are brief tests capable of reflecting grammatical difficulty in spontaneous speech. [ABSTRACT FROM AUTHOR]

Almost one-third of the participants in a neuropsychological study signed the consent form below the given line. The relationship between a signature position on or below the line and participants’ cognitive function was investigated. Fifty drug-dependent individuals, 50 of their siblings, and 50 unrelated control participants completed a battery of neuropsychological tests using the Cambridge Neuropsychological Test Automated Battery (CANTAB). Individuals signing below, rather than on, the line performed more poorly on tests of visuospatial memory, but no differently on other cognitive tests. Signature positioning may be a soft sign for impairment of the mechanisms involved in visuospatial memory. [ABSTRACT FROM AUTHOR]

Exaggerated effects of word length upon reading-aloud performance define pure alexia, but have also been observed in semantic dementia. Some researchers have proposed a reading-specific account, whereby performance in these two disorders reflects the same cause: impaired orthographic processing. In contrast, according to the primary systems view of acquired reading disorders, pure alexia results from a basic visual processing deficit, whereas degraded semantic knowledge undermines reading performance in semantic dementia. To explore the source of reading deficits in these two disorders, we compared the reading performance of 10 pure alexic and 10 semantic dementia patients, matched in terms of overall severity of reading deficit. The results revealed comparable frequency effects on reading accuracy, but weaker effects of regularity in pure alexia than in semantic dementia. Analysis of error types revealed a higher rate of letter-based errors and a lower rate of regularizaron responses in pure alexia than in semantic dementia. Error responses were most often words in pure alexia but most often nonwords in semantic dementia. Although all patients made some letter substitution errors, these were characterized by visual similarity in pure alexia and phonological similarity in semantic dementia. Overall, the data indicate that the reading deficits in pure alexia and semantic dementia arise from impairments of visual processing and knowledge of word meaning, respectively. The locus and mechanisms of these impairments are placed within the context of current connectionist models of reading. [ABSTRACT FROM AUTHOR]

Background: The importance of connected speech analysis in the diagnosis and further classification of primary progressive aphasia (PPA) is becoming apparent. However, methodological inconsistencies in elicitation and analysis of speech samples hinder comparison of different laboratories' results. The recent recommendations for further classification of PPA have characterised three main variants, but we have demonstrated that a considerable proportion of patients do not conform to any of these, as their language deficits extend beyond those of a single syndromic variant (mixed PPA). This report is an attempt to characterise the language profiles of different non-semantic variants of PPA using a combination of connected speech analysis and standard neuropsychological tests. Aims: Our aims were (a) to assess the relative efficacy of semi-structured interviews and picture description tasks in revealing the important aspects of language deficit in our patient groups, (b) to document the language profile of a mixed PPA group for the first time, (c) to compare the patterns of speech abnormality in non-fluent variant and mixed PPA, relative to each other and to normal control participants, and (d) to identify those features of spontaneous speech decline that are frequent and tangible enough to be detected during clinical consultations. Methods & Procedures: Connected speech samples obtained from picture description and semi-structured interviews were analysed quantitatively and the outcomes were contrasted between the elicitation methods and among the participant groups. Due to a very small number of cases fulfilling criteria for logopaenic PPA, the speech of these patients was scrutinised individually. Outcomes & Results: Pair-wise comparisons of the two speech elicitation methods at a group level revealed only a partial concordance and greater sensitivity of semi-structured interviews in detecting different aspects of speech abnormality. At a group level there was a significant impairment in the morpho-syntactic aspects of connected speech in both non-fluent and mixed PPA. A statistically significant difference from controls was observed in the semantic measures of discourse only in the mixed PPA group. Clinically useful features that differentiate both non-fluent and mixed PPA groups from healthy volunteers were decreased speech rate, shorter utterances, fewer complex grammatical structures, lack of spontaneity, more non-sentential speech units (elliptical and abandoned units), more hesitation markers, and, to a lesser extent, more phonological errors and editing breaks. Conclusions: The combination of the present results with those from our previous report on semantic dementia that used the same methodology offers a quantitative detailed assessment of connected speech across the spectrum of PPA. [ABSTRACT FROM AUTHOR]

Background: Neurodegenerative syndromes are associated with varying degrees of language impairment. Connected speech analysis provides the most realistic measure of language function but its use has been restricted by operational constraints. Aims: In this prospective study we assessed the relative utility of a picture description task and a semi-structured interview in exposing the language decline in semantic dementia (SD) and typical mild Alzheimer's disease (AD), compared to each other and to healthy volunteers. Methods & Procedures: Our cohort comprised 16 patients with a clinical diagnosis of SD, 20 with mild typical AD, and 30 healthy participants. All speech samples were recorded during a face-to-face interview and were subjected to a well-controlled quantitative analysis. Outcomes & Results: Our results suggest that (a) the picture description task is more sensitive to abnormalities in the semantic measures, whereas the interviews are better at exposing morpho-syntactic deficits; (b) circumlocution is not, as has sometimes been claimed, a salient feature of speech in SD; (c) increases in the frequency of hesitation markers and of phonological and syntactic errors are prominent features of language decline in mild AD; and (d) a 150-word interview sample is adequate to provide a realistic reflection of language impairment. Conclusions: This study compared, for the first time, the two most commonly used methods of eliciting connected speech and documented many similarities in results from the two but also some salient differences in their sensitivity to specific aspects of language deficit. In addition, although replicating some aspects such as anomia, of what is already known about the language impairments in these two conditions, the study provides novel findings for both that could help clinicians in syndromic classification of anomic speech. [ABSTRACT FROM AUTHOR]

In this commentary, though acknowledging that a case-series approach in neuropsychology is not always possible, we set out a series of considerations that in our view make this approach generally superior to single-case study. We argue that case-series designs are crucial for theory-testing, assessment of computational models, evaluation of inter-patient variation (including selection criteria, patient homogeneity/heterogeneity, premorbid individual differences, etc.) and to establish solid foundations for the interpretation of behavioural dissociations and associations. We conclude by suggesting that, alongside other neuroscience techniques, case-series cognitive neuropsychology provides a crucial contribution to the future of clinical and cognitive neuroscience. [ABSTRACT FROM AUTHOR]

The aims of this study were (a) to explore the utility of, and make more widely available, an updated and extended version of the Cambridge Semantic Memory test battery, and (b) to use this battery in conjunction with other tests to characterise the profile of several different forms of progressive cognitive impairment: semantic dementia (SD, n = 15), mild cognitive impairment (MCI, n = 7), established Alzheimer's disease (AD) (n = 8), all in comparison to normal controls (n = 45). The semantic battery is useful in a variety of ways for exploring the nature of semantic deficits; on its own, however, it does not provide sensitive differentiation between patients with AD and SD. An assessment including measures of episodic memory and visuospatial abilities as well as the semantic battery is recommended for good characterisation of the cognitive profiles associated with SD and AD. [ABSTRACT FROM AUTHOR]

Semantic memory impairment, from either non-progressive or neurodegenerative brain injury, has a significant impact on day-to-day functioning. Few studies have investigated the best methods for supporting relearning of new semantic knowledge in semantically-impaired individuals, even though these investigations also provide an opportunity to explore how the hippocampal and temporal neocortical systems interact in the acquisition of semantic facts. In the current study, four participants (three who had suffered from herpes simplex viral encephalitis and one with a diagnosis of semantic dementia) were asked to learn new facts about famous people using mnemonic and errorless learning paradigms. Home practice was also encouraged. Training resulted in significant improvements to all participants' naming of the individual and recall of a semantic fact about the famous person. Learning was maintained when home practice ceased. Learning also generalised to naming of a different photograph in three individuals, although generalisation of naming to a different semantic fact was less robust. This study confirms that errorless learning paradigms can be used to help boost naming and semantic knowledge in semantically-impaired individuals. This finding supports theoretical accounts in which different temporal structures are capable of supporting acquisition of new semantic facts independently, albeit less efficiently than when both systems are available. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this study, we explored capacities for three different aspects of short-term verbal memory in patients with semantic dementia. As expected, the two patients had poor recall for lexico-semantic item information, as assessed by immediate serial recall of word lists. In contrast, their short-term memory for phonological information was preserved, as evidenced by normal performance for immediate serial recall of nonword lists, with normal or increased nonword phonotactic-frequency effects, and increased sensitivity to phonological lures in a delayed probe recognition task. Furthermore, the patients appeared to have excellent memory for the serial order of the words in a list. These data provide further support for the proposal that language knowledge is a major determining factor of verbal STM capacity, but they also highlight the necessary distinction of processes involved in item and order recall, as proposed by recent models of STM. [ABSTRACT FROM AUTHOR]

In pure alexia (PA)—an acquired reading disorder consequent on posterior left-hemisphere stroke—the hallmark is a pronounced and abnormal impact of word length on reading speed. Some patients with semantic dementia (SD)—a neurodegenerative condition affecting semantic memory—have also been reported to show an abnormal word length effect (AWLE) in reading, even though they are not thought to have the basic visual-processing deficits hypothesized to underlie this phenomenon in PA. In the current study, an AWLE in reading was consistently observed in both PA and SD patients, but further manipulations demonstrated marked differences between the groups in the conditions that produce the length effect, its specific manifestation, and the pattern of other deficits accompanying it. All of the results are compatible with the twin hypotheses that the AWLE in reading arises from a visual-processing deficit in PA but from reduced top-down lexical/semantic support for word identification in SD. In other words, the AWLE in the two patient groups appears to be a common symptom arising from different underlying deficits: one bird with two stones. [ABSTRACT FROM AUTHOR]

Background : The speech of patients with progressive non‐fluent aphasia (PNFA) has been described as similar to that in non‐fluent aphasia (NFA) consequent on stroke. There are, however, few direct empirical comparisons of these two patient populations in the literature. Aims : To test the hypotheses that PNFA cases differ from NFA (a) in the extent to which their speech production deficit varies as a function of speaking task, and (b) in the nature of their phonological deficit. Methods & Procedures : Groups of PNFA and NFA patients ( N = 10 each), matched on scores in a picture‐naming test, were assessed on tasks of narrative picture description, reading aloud of text and single words, and phonological abilities such as rhyme judgement and rhyme production. Outcomes & Results : (a) The NFA cases showed equivalent speech rates in self‐generated speech and reading text aloud, and equivalent error rates when reading text or isolated single words. In contrast, the PNFA cases spoke more rapidly when reading aloud than when producing narrative speech, and achieved higher accuracy when reading single words aloud than when reading words in text. (b) Variation in success rate for reading different types of words (e.g., content words, function words, and nonsense words), error types in reading, and performance on phonological tasks all indicated a different and better quality of phonological processing in PNFA than NFA. Conclusions : Despite some surface similarities, there are telling differences between the speech impairments in PNFA and NFA. The deficit in PNFA particularly compromises self‐generated connected speech. [ABSTRACT FROM AUTHOR]

Relatively little is known about the neuropsychological profile of late-stage semantic dementia. This article provides a detailed assessment of patient MK who, despite her very severe semantic impairments, remained cooperative to testing and, unusually, did not show additional behavioral/personality changes. Although MK’s initial presentation was typical of semantic dementia (SD), her performance began to deviate from the normal pattern. She developed impairments of single word repetition and regular word reading, and began to produce phonological errors in picture naming and spontaneous speech. These deficits might suggest that late-stage SD includes an independent disorder of phonology. An alternative possibility, however, is that phonological processing cannot proceed normally in the face of profound semantic degradation. A series of experiments supported the latter explanation of MK’s deficits. In picture naming, MK showed little effect of progressive phonological cueing, did not reveal an increased sensitivity to word length or phonological complexity and continued to show a high degree of item-specific consistency in both accuracy and errors: she tended to produce the same erroneous phonemes for each item. She remained sensitive to the effects of phonological similarity in immediate serial recall. Letter substitution errors in regular word reading were more common for lower frequency letters (e.g., Q, Z). These letters also produced more item errors in immediate serial recall, suggesting that a frequency-graded loss of letter knowledge, rather than separate orthographic and phonological deficits, accounted for the deficits in both of these tasks. These findings are discussed in terms of theories that posit strong interactivity between phonology and semantics. [ABSTRACT FROM AUTHOR]

This article describes a 52-month longitudinal study of a patient, ILJ, whose semantic profile fits the criteria for a classical case of semantic dementia (SD). As in all such cases, it was the semantic aspects of receptive and expressive language processing—essentially vocabulary—that were most dramatically affected. The novel observation from this study is ILJ’s performance on a comprehensive language examination. Results from this assessment, even early in the course of his disease, are compatible with the hypothesis that phonological, morphological and/or syntactic aspects of language processing may be disrupted by their interaction with degraded information from the semantic system. [ABSTRACT FROM AUTHOR]

This article describes a 52-month longitudinal study of a patient, ILJ, whose semantic profile fits the criteria for a classical case of semantic dementia (SD). As in all such cases, it was the semantic aspects of receptive and expressive language processing--essentially vocabulary--that were most dramatically affected. The novel observation from this study is ILJ's performance on a comprehensive language examination. Results from this assessment, even early in the course of his disease, are compatible with the hypothesis that phonological, morphological and/or syntactic aspects of language processing may be disrupted by their interaction with degraded information from the semantic system. [ABSTRACT FROM AUTHOR]

This study addressed the question of exactly which aspects of spelling-sound consistency influence accuracy of reading aloud in surface dyslexic patients with semantic dementia. Oral reading data were obtained from twelve patients on three sets of words that varied in regularity (defined according to grapheme-phoneme correspondences) and consistency (defined according to the pronunciation of word body neighbours). The patients were less accurate for irregular/inconsistent words, which they commonly pronounced in line with sound-spelling regularities, as expected in surface dyslexia. They produced plausible but incorrect responses for some regular as well as many irregular words, suggesting that their reading performance was influenced by sound-spelling relationships not captured by grapheme-phoneme correspondences. On a set of items that varied consistency and regularity independently, the patients showed a large effect of regularity and a smaller but significant effect of consistency in reading aloud. In addition, there was a correlation between degree of semantic impairment and level of reading accuracy for inconsistent items. These findings are discussed in terms of two influential models of reading: the dual-route-cascaded model (Coltheartet al., 2001) and the triangle model (Plautet al., 1996). It is argued that the triangle model provides a more straightforward account of the relationship between word comprehension and consistency effects in reading. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the ability of a patient with semantic dementia to relearn to use objects that had, through the process of disease, become alien to her. Following only a brief demonstration of their use, JH achieved nearly perfect scores on the overall use of 10 previously familiar objects. This dramatic boost in performance did decline steadily over time without any practice. Even five weeks after the initial training, however, JH was still able to achieve an average score of around 60%, which was significantly greater than at baseline assessment and sufficient to enable partially correct use of the objects. The results of this study demonstrate that it is possible for a patient in the advanced stages of semantic dementia, with severely degraded conceptual knowledge, to relearn to manipulate objects through observation of their use. With continual reinforcement, in the form of more frequent training and practice sessions, it is likely that this improved performance could be maintained over time. A rehabilitation programme based on this research may provide a rare opportunity for improvement in the face of this progressive disease: a glimmer of hope while many other cognitive functions are deteriorating. [ABSTRACT FROM AUTHOR]

Fourteen patients with nonfluent progressive aphasia (NFPA) performed a picture description task in both spoken-and written-output conditions, as well as tests of confrontation naming, spelling to dictation and reading aloud of single words and text. Relative to controls, the patients' spoken and written picture descriptions were reduced in length, speed and amount of information. Of particular interest, and accounting for the first part of the article's title, was a pervasive pattern of poorer spoken and written output associated with the requirement to produce more; this was true when 'more' meant either (a) longer vs. shorter single words or (b) connected language vs. single words. Deficits in spoken and written naming were largely parallel, and modality-specific output impairments (such as dysarthria in speech or letter-formation problems in writing) seemed to account for the minority of cases who exhibited a discrepancy. Most patients showed no evidence of agrammatism or of reduced verb production in their speech, which typically had normal proportions of content and function words as well as nouns and verbs. By contrast, some degree of telegraphic output was observed in the written narratives of a number of the patients. Our results argue against several candidates for the main functional locus of impairment in NFPA, but it is likely that deficits in grammatical processing, working memory, planning/executive skills, speech motor abilities and phonological processing all play a role. [ABSTRACT FROM AUTHOR]

This study was designed to investigate the impact of semantic deficits on the recognition of words and objects as real/familiar. Two-alternative forced-choice tasks of lexical decision and object decision were each administered to a case series of patients with semantic dementia. In both tasks, the critical manipulation was whether the real word or object was more or less "natural" (i.e., typical of its domain) than the nonword or nonobject with which it was paired. For lexical decision, typicality of the words and nonwords was manipulated in terms of bigram and trigram frequencies of the letter strings. For object decision, high typicality in real and chimeric objects consisted in having only or mainly visual features that are standard for objects in that category. This manipulation of relative typicality of real and made-up stimuli exerted a dramatic influence on the patients' success in both lexical and object decision. The patients' strong tendency towards "natural selection" was further modulated by both the frequency/familiarity of the real words/objects and the degree of semantic degradation of the individual patients. This outcome is in line with the authors' model of semantic knowledge and the impact of its degradation on a wide range of cognitive behaviour. [ABSTRACT FROM AUTHOR]

Although patients with semantic deficits can sometimes show good performance on tests of object decision, we present evidence that this pattern applies when nonsense-objects do not respect the regularities of the domain. In a newly designed test of object-decision, 20 patients with semantic dementia viewed line drawings of a real and chimeric animal side-by-side, and were asked to decide which was real. The real animal was either more typical (real > nonreal) or less typical (nonreal > real) than the chimera. Performance was significantly better in the real > nonreal condition, and success in both conditions was modulated by patients' degree of semantic impairment. A similar effect of item typicality was revealed in a subset of items selected from a standard test battery. Object-decision scores were highly correlated with other pictorial and verbal assessments of conceptual knowledge, suggesting that impaired performance on all tasks resulted from the degradation of a unitary underlying system. [ABSTRACT FROM AUTHOR]

Background: How similar is the "architecture" of language function in different languages? In the domain of reading and writing, the relationship between orthographic and phonological units of the language differs dramatically between alphabetic and logographic writing systems. It is therefore appropriate to ask whether an architecture assumption, such as direct links between word pronunciations and their written forms, developed in the course of research on English and other alphabetic writing systems, applies to logographic Chinese. Aims: We describe a native Cantonese speaker, TUA, with an acquired dysgraphia following a right hemisphere stroke. The study was designed to identify the conditions under which TUA succeeded or failed to produce the correct orthographic form of words in his native language, and thereby to draw inferences about his impaired and intact writing procedures with further implications for normal writing. Methods & Procedures: Nine different single-word tests were administered to TUA, mainly of writing to dictation but also of written picture naming and other relevant skills. Almost all monosyllabic words in Cantonese are homophones and, in the majority of our tests, the target words were lower-frequency homophones, with the intended alternative disambiguated by a semantic cue. Outcomes & Results: TUA made few errors in writing high-frequency words to dictation, but had error rates as high as 60-70% on lower-frequency homophonic target words. The majority of his errors were homophones of or at least closely phonologically related to, the target item. This deficit in writing to dictation co-existed with adequate ability to define the correct lower-frequency homophonic alternative, and with the unusual pattern of more correct responses in written picture naming than in writing to dictation of the same target items. Although TUA's poor performance in writing was accompanied by several nonlinguistic impairments (e.g., in visual memory,... [ABSTRACT FROM AUTHOR]

Patients with semantic dementia, the temporal variant of frontotemporal dementia, are relevant to both the neuroanatomical and neuropsychological debates in the category-specific literature. These patients present with a selective and progressive semantic deficit consequent on circumscribed atrophy of the inferolateral polar temporal lobes bilaterally, including the inferotemporal gyrus. In this study, a patient KH with a significant advantage for artefacts over living things was compared to five other semantic dementia patients with commensurate levels of semantic impairment. KH demonstrated a consistent category difference in favour of artefacts across all the expressive and receptive semantic tests. This difference was reliable even when familiarity, frequency, and other potential confounding factors were controlled. While KH demonstrated an association between poor knowledge of sensory attributes and a consistently greater impairment on living things than artefacts, the other patients did not. As observed in a number of previous studies, all five of the patients, contrasted to KH, exhibited an advantage for functional/associative over sensory attributes but without demonstrating the category-specific deficit that the sensory-functional theory (and the locus of their atrophy) might predict. The results of this and other studies are discussed in relation to four accounts of category specificity: the sensory-functional theory, domain-specific knowledge systems, intercorrelated features, and individual differences. [ABSTRACT FROM AUTHOR]

Presents a study on patients with semantic dementia in cognitive neuropsychology. Drawings of concrete concepts made by semantic dementia patients from dictation of their names; Importance of semantic memory in humans; Use of feature analysis to evaluate the drawings made by the patients.

The predominant, and most socially isolating, symptom typically seen in semantic dementia is anomia—word-finding difficulties—in conjunction with a deteriorating central semantic system. In this paper, we demonstrate that repeated rehearsal of the names of concepts paired with pictures of them and/or real items resulted in a dramatic improvement in the ability of a patient (DM) with semantic dementia to produce previously "difficult-to-retrieve" words on tests of word production. Although the substantial improvement shown by DM suggests that home rehearsal with pictorial and verbal stimuli could be a useful rehabilitative strategy for word-finding difficulties in semantic dementia, the experiment also revealed that constant exposure to items was necessary in order to prevent the observed decline in performance once DM's daily drill was stopped. The results are discussed with respect to the underlying neuroanatomical structures thought to be important for the acquisition and storage of long-term memory, and to techniques for facilitating word-finding in patients with aphasia. [ABSTRACT FROM AUTHOR]

This paper presents a long-term follow-up study of a dysgraphic patient reported in an earlier paper (Graham, Patterson, & Hodges, 1997). FM developed "jargon dysgraphia": In writing to dictation, she fluently produced well-formed written output consisting of pronounceable neologisms which, over time, bore a progressively weaker resemblance to the target words (e.g., scribe → SCRIPE, January 1992; → SRIME, November, 1994; → BRINCE, August, 1996; → MEATH, November, 1997). Although this spelling disorder has been (rarely) reported in patients with stable brain lesions, this is the first time that it has been documented in the context of progressive disease, a situation that provided a unique opportunity to document its characteristics at different stages. Longitudinal results from a spelling-to-dictation task showed that FM was, for a time, able to activate at least partial orthographic information, even after her overall accuracy (assessed in terms of the number of words spelled completely correctly) had reached the floor. For example, her error responses were correlated in length with the targets, and contained a larger than chance number of letters that overlapped between target and response. Ultimately, FM's spelling responses had no detectable similarity with the targets, although they remained word-like in that they were pronounceable and contained few illegal letter combinations. [ABSTRACT FROM AUTHOR]

Many cognitive psychological, computational, and neuropsychological approaches to the organisation of semantic memory have incorporated the idea that concepts are, at least partly, represented in terms of their fine-grained features. We asked 20 normal volunteers to provide properties of 64 concrete items, drawn from living and nonliving categories, by completing simple sentence stems (e.g., an owl is __, has __, can__). At a later date, the same participants rated the same concepts for prototypicality and familiarity. The features generated were classified as to type of knowledge (sensory, functional, or encyclopaedic), and also quantified with regard to both dominance (the number of participants specifying that property for that concept) and distinctiveness (the proportion of exemplars within a conceptual category of which that feature was considered characteristic). The results demonstrate that rated prototypicality is related to both the familiarity of the concept and its distance from the average of the exemplars within the same category (the category centroid). The feature database was also used to replicate, resolve, and extend a variety of previous observations on the structure of semantic representations. Specifically, the results of our analyses (1) resolve two conflicting claims regarding the relative ratio of sensory to other kinds of attributes in living vs. nonliving concepts; (2) offer new information regarding the types of features—across different domains—that distinguish concepts from their category coordinates; and (3) corroborate some previous claims of higher intercorrelations between features of living things than those of artefacts. [ABSTRACT FROM AUTHOR]

We present a longitudinal investigation of the language deficits of RB and CB, two brothers with primary progressive aphasia. Experiments 1 to 5 assessed word production in picture naming, naming with progressive phonemic cueing, reading, immediate and delayed repetition of single words, and repetition of two-word strings. Experiment 6 investigated receptive word processing using a picture-name judgement task with phonologically related, semantically related, and unrelated distractors. RB was less successful in naming than CB, and made most errors to semantically related distractors in the input task, whereas CB was more impaired than RB in repetition tasks and in detecting phonological distractors at input. The brothers are considered to have different processing deficits with reference to an interactive spreading activation model of speech production (Dell, 1986; Martin & Saffran, 1992). [ABSTRACT FROM AUTHOR]

We present evidence from a fluent aphasic subject with intact comprehension but moderate word-finding difficulties. Despite her anomia in picture naming, MOS displayed normal performance in reading aloud, even when tested on lower-frequency words with atypical spelling-to-sound correspondences. We argue that, contrary to some recent interpretations of preserved reading with impaired naming, this pattern does not demonstrate separate task-specific speech lexicons, but rather reflects inherent differences between the processes of naming and reading. In support of this hypothesis, when given appropriate assistance (in this case multi-phonemic cueing), MOS achieved picture naming scores within normal limits. [ABSTRACT FROM AUTHOR]

We studied two patients with a novel focal neurodegenerative syndrome: a progressive dysgraphia in which both central (linguistic) and peripheral aspects of the writing process were affected. In one patient the dysgraphia was remarkably pure. Longitudinal testing over roughly 4 years showed that the dysgraphia evolved in a broadly similar pattern for both patients. At presentation, SC and FM exhibited (central) surface dysgraphia on both oral and written spelling. Over time, nonphonologically plausible spelling errors increased, and eventually became the dominant response type for both patients in both response modes. The peripheral dysgraphia consisted of difficulty with producing letters, particularly in lower case, without a model to copy. Examination of a further 28 dysgraphic patients with cortical dementia revealed a strong concordance between spelling and letter production problems, indicating that the association is more common than previously recognised. Although this association may simply reflectpathological involvementof functionally and anatomically closely related brain regions, we also sketch a proposal for a principled relationship amongst the disorders observed in these cases. Damage to an interactive system with wordand letter-based levels of representation could plausibly result in initial surface dysgraphia, together with the progressive emergence of nonphonologically plausible spelling errors, and a deficit in letter production. [ABSTRACT FROM AUTHOR]

Two case studies are presented of the short-term memory performance of patients with semantic dementia. The first case showed a pervasive pattern of semantic effects in his auditory verbal short-term memory performance, in particular a marked superiority in serial recall for sequences of ''know n" words over ''unknown" w ords- words w hich he no longer comprehended. His performance in serial recall tasks was characterised by abundant phonemic errors, which occurred w ith a frequency show n to be related to semantic factors. These errors were often migrations of phonemes from one word in the list to another, suggesting that impaired semantic processing reduces the ''glue" or ''binding" that helps to maintain a structured sequence of phonemes in short-term memory. The second patient also showed some semantic effects in serial recall, and a significant but less marked pattern of phonological errors. The differing performance of the two patients is interpreted w ithin an interactive activation model of word production (Saffran & Martin, 1990; Martin, Saffran, & Dell, 1996). [ABSTRACT FROM AUTHOR]

A Japanese patient displayed a striking phonological alexia after a lefthemisphere CVA: KT's accuracy in reading real kanji or kana words was essentially normal; but asked to read simple 2-3-character kana strings with orthographically and phonologically unfamiliar form (nonwords), on which normal Japanese readers easily score 100% , he consistently failed to produce a single correct response. The introduction of phonological familiarity (i.e. creating nonwords homophonic with real words) produced a dramatic facilitation of KT's nonword reading, and this marked "pseudohomophone" effect furthermore interacted with both frequency and concreteness of the words whose pronunciations were mimicked in the nonwords. KT also showed prominent deficits and lexicality effects in phonological tasks such as segmentation and blending that involve no orthographic processing. His pattern of language and reading performance is interpreted as a deficit in which pathologically reduced activation of phonological representations has differential consequences for word and nonword production. [ABSTRACT FROM AUTHOR]

A pattern of highly selective impairment in reading nonwords is described in a Japanese patient, TY, who achieved essentially normal performance on most of a range of other language abilities tested. Other prominent features of TY's reading were: (1) almost flawless reading of all types of familiar words in both kanji and kana; (2) differential performance, both quantitative and qualitative, on three types of nonwords constructed by altering real words in various ways; (3) dramatic improvement in pronunciation of orthographic nonwords with phonologically familiar pronunciations (pseudohomophones); and (4) from near-normal to impaired performance on different types of mora-based phonological manipulation tasks. With reference to the so-called "triangle" framework of reading (Plaut, McClelland, Seidenberg, & Patterson, 1996; Seidenberg & McClelland, 1989), these characteristics are interpreted to arise from an impaired phonological production system in which activation tends to fall into familiar patterns corresponding to real words. An alternative account of TY's performance in terms of the recent dual-route cascaded model (Coltheart, Curtis, Atkins, & Haller, 1993) is also discussed. [ABSTRACT FROM AUTHOR]

Introduces a section or articles on connected speech disorders as part of a special issue in tribute to language researcher Eleanor Saffran. Her development of Quantitative Production Analysis, a quantitative analysis technique for assessing speech production; Her work with agrammaticism; Her research with aphasic patients on the relationship between language and verbal short-term memory; Results of her studies of patients with semantic impairments.

There is no abstract with this paper [ABSTRACT FROM AUTHOR]