Aphasic Speakers Research Articles

Mild Aphasia: Is This the Place for an Argument?

Individuals with mild aphasia often report significant disruption to their communication despite seemingly minor impairment. This study explored this phenomenon through examining conversations of a person with mild aphasia engaging in argumentation--a skill she felt had significantly deteriorated after her stroke. A person with mild aphasia and her husband recorded 4 conversations involving topical issues. The discourse dynamics and lexical-grammatical content were analyzed using systemic functional linguistic (Halliday & Matthiessen, 2004) and conversation analysis (Sacks, Schegloff, & Jefferson, 1974) frameworks. The couple demonstrated similarities in the types of conversational moves, but the language of the person with aphasia was more nonspecific and simplified, manifesting in difficulties developing a logical argument and responding to the partner's line of argument. In addition, the nonaphasic speaker recurrently overlapped the aphasic speaker in order to request clarification of particular points, highlighting the types of behaviors that can occur in this form of higher level language activity. The complex argument task and the multilevel and multi-approach analysis are useful tools for examining persons with mild aphasia, revealing aspects that are often overlooked in standard tests. Treatment could incorporate more complex notions such as evaluative language and the role of overlap in complex conversations.

Combining possibly reciprocally dependent linguistic parameters in the quantitative assessment of aphasic speakers' grammatical output

Background: The grammatical output of aphasic speakers is often quantitatively analysed in order to establish an effect of treatment. In many methods of quantitative analysis both the number of utterances produced and (their) length are calculated. The difficulty is that these parameters may show a trade-off effect (i.e., may be inversely proportional to each other). That is, when the amount of information to be conveyed remains constant, an increase in the number of utterances may be compensated by a decrease in their length (and vice versa). As a result, a lack of increase—or even a decrease—in one of both outcome measures may be incorrectly interpreted as a lack of effect of treatment. Aims: The current study investigated whether combining the possibly reciprocal outcome measures percentage of utterances and (their) length into a single parameter increases the interpretability of the results obtained with a quantitative analysis of aphasic speakers' spontaneous speech. In the current study the procedure of combining two possibly reciprocal linguistic variables into one dependent measure is demonstrated for the elliptical repertoire. Ellipses are grammatically well formed but incomplete utterances (e.g., problem solved). Contrary to sentences, ellipses lack finiteness. As will be argued in this article, the procedure of combining possibly reciprocal outcome measures could be useful in order to investigate both the sentential and elliptical repertoire produced by aphasic speakers. Methods & Procedures: The possibly reciprocal outcome measures percentage of ellipses and mean length of ellipsis, which were used in the study of Ruiter, Kolk, and Rietveld (2010), were combined into a single parameter of elliptical style: percentage of words produced in ellipses (in comparison to words in sentences). The data obtained by Ruiter et al. (2010), who investigated the effect of a compensation therapy on the production of ellipses in 12 chronically agrammatic speakers of Dutch, were re-analysed with the new parameter. Outcomes & Results: The parameter percentage words produced in ellipses was not only able to reproduce the results obtained in the previous study, but also seems to be more sensitive: It could identify significant changes in elliptical style in more participants than the two possibly reciprocal parameters could independently. Conclusions: The data obtained in the current study may be of relevance to aphasia researchers and therapists as the new parameter provides them with a more sensitive measure to establish the effect of therapy on aphasic speakers' grammatical output.

Why reference to the past is difficult for agrammatic speakers

Many studies have shown that verb inflections are difficult to produce for agrammatic aphasic speakers: they are frequently omitted and substituted. The present article gives an overview of our search to understanding why this is the case. The hypothesis is that grammatical morphology referring to the past is selectively impaired in agrammatic aphasia. That is, verb inflections for past tense and perfect aspect are hard to produce. Furthermore, verb clusters that refer to the past will be affected as well, even if the auxiliary is in present tense, as in he has been writing a letter. It will be argued that all these verb forms referring to the past require discourse linking [Zagona, K. (2003). Tense and anaphora: Is there a tense-specific theory of coreference. In A. Barrs (Ed.), Anaphora: A reference guide (pp. 140–171). Oxford: Blackwell Publishing] and discourse linking is affected in agrammatic aphasia [Avrutin, S. (2006). Weak syntax. In K. Amunts, & Y. Grodzinsky (Eds.), Broca's region (pp. 49–62). New York: Oxford Press]. This hypothesis has been coined the PAst DIscourse LInking Hypothesis (PADILIH) [Bastiaanse, R., Bamyaci, E., Hsu, C.-J., Lee, J., Yarbay Duman, T., & Thompson, C.K. (2011). Time reference in agrammatic aphasia: A cross-linguistic study. Journal of Neurolinguistics, 24, 652–673]. The PADILIH has been tested in several languages and populations that have hardly been studied before in aphasiology: languages such as Turkish, Swahili and Indonesian were included, as well as monolingual and bilingual populations. In all these populations, the same test has been used: the Test for Assessing Reference of Time [Bastiaanse, R., Jonkers, R., & Thompson, C.K. (2008). Test for assessing reference of time (TART). Groningen: University of Groningen] to enable reliable comparisons between the languages. The results show that the PADILIH predicts the performance of agrammatic speakers very well: discourse-linked grammatical morphemes expressing time reference to the past are hard to produce for agrammatic speakers, whereas non-discourse-linked verb inflections (for present and future) are relatively spared. In languages that use aspectual adverbs (free-standing and optional time reference markers), such as Chinese and Indonesian, time reference to all time frames is impaired, since all aspectual adverbs, regardless of the time frame they refer to, require discourse linking. Remarkably, the problems are not restricted to grammatical morphemes: the production of temporal lexical adverbs is impaired as well.

Choosing Not to Repair: Sorry as a Warrant for Interactional Progress

Problems in conversation with those who suffer from aphasia often result in long sequences of repair, hindering progress. This article identifies an aphasic speaker's creative adaptation of a familiar linguistic resource to try and get around the problem. He uses the lexical apology sorry as a resource to close down collaborative word searching and to move the conversation forward. The analysis shows how he mobilizes the linguistic properties of the word to render it interpretable by the coparticipant in the interaction. We also see how his use of sorry to move the conversation on depends for its effect on epistemic authority—what both parties to the interaction know about the topic under discussion.

Linguistic encoding of motion events in English and French

Languages show differences in how they encode motion in discourse: Verb-framed languages lexicalize Path in the verb, leaving Manner peripheral or implicit; Satellite-framed languages lexicalize Manner together with Path adjuncts. The present study investigates: 1) the extent to which such typological constraints affect the verbalizations of second language learners (English learners of French) and of aphasic speakers (English and French speakers with agrammatism) — who typically show dissociations between lexical and syntactic knowledge — in comparison to controls (English and French native speakers); as well as 2) the role of language-independent factors (level of acquisition, syndrome type). Despite some similarities between learners and speakers with aphasia due to language-independent factors, the findings suggest typologically constrained verbalizations in all groups, as well as diverging strategies that may reflect distinct underlying conceptualization processes.

Aspects of time: Time reference and aspect production in Russian aphasic speakers

Cross-linguistic data suggest that the grammatical categories of tense and aspect are not generally impaired in individuals with aphasia (see Bastiaanse et al., 2011 for a review). Rather, and more specifically, verb forms expressing reference to the past or conveying perfective semantics are more impaired than verb forms expressing reference to the non-past (present or future) or conveying imperfective semantics, both in comprehension and production. The present study used some structural properties of Russian to systematically test the interaction of time reference and aspect in non-fluent and fluent aphasia. The Test for Assessment of Reference of Time (TART; Bastiaanse, Jonkers, & Thompson, 2008; Russian version Dragoy & Bastiaanse, 2010) was used to elicit production of four verb forms in sentence context: past perfective, non-past perfective, past imperfective and non-past imperfective. The results showed that non-past time reference had a general advantage over past time reference, all aspectual forms being collapsed. However, an interaction between time reference and aspect was found: imperfective verbs were better produced in the non-past, whereas production of perfective verbs was better preserved in the past time frame. Non-fluent and fluent aphasic speakers showed largely overlapping performance. These results demonstrated that the advantage of a particular time reference depends on aspectual characteristics of the verb. The performance of both non-fluent and fluent aphasic speakers can be

Expressing Opinions and Feelings in a Conversational Setting

This article examines the ways in which individuals with aphasia communicate opinions and feelings using evaluative language during conversation in an aphasia group. Evaluative language refers to semantic resources conveying emotions, judgments, and valuations and includes emotive adjectives, nouns, verbs, and adverbs as well as metaphor. Although individuals with aphasia are known to be able to use evaluative language in a monologic context, little is known about how people with aphasia use evaluative language in conversation, or about the role of co-construction in such usage. The data for this study were collected during a conversation group consisting of five participants with aphasia and a facilitator. The analysis used is based on Appraisal theory (Martin and White 2005) and examined the evaluation categories of Affect, Appreciation, Judgment, and Graduation. Regardless of severity, all aphasic speakers contributed an equal amount of evaluation to the interaction and demonstrated some usage of all types of evaluation. However, those with more severe aphasia relied heavily on their conversational partners to scaffold their opinions and used a range of resources including lexical items, such as exactly, and repetition (e.g., "yeah yeah yeah") to agree emphatically with opinions expressed. Lexical variety was notably less in the aphasic speakers than the non-brain-damaged group facilitator. The article discusses the patterns of skills observed together with the clinical implications for working with people with aphasia on emotional meanings.

Objective automated analysis of natural language: The Fluency Profiling System as a measure of the efficiency of dynamic language networks.

Event Abstract Back to Event Objective automated analysis of natural language: The Fluency Profiling System as a measure of the efficiency of dynamic language networks. Kathryn M. Hird1, 2*, Kim Kirsner1, 2, Daniel Little3, Raoul Oehmen1, 2 and John Dunn4 1 University of Notre Dame, Australia 2 University of Western Australia, Australia 3 University of Melbourne, Australia 4 University of Adelaide, Australia Recent advances in neuro-imaging have provided biological confirmation of the presence of large-scale networks underpinning language processing (Thompson & den Ouden, 2008). Fluent effortless speech production is thought to reflect optimum network function. Hird and Kirsner (2010) demonstrated in three diverse aphasic speakers that the Fluency Profiling System (Little, Oehmen, Dunn, Hird & Kirsner (2012) provides a powerful, objective and sensitive profile of fluency in natural speech samples. Discourse samples from the Cinderella story were selected from the AphasiaBank repository (McWhinney et al., 2011) if they met an empirically defined Signal: Noise ratio. To date a total of 28 cases have been analysed: 18 with a diagnosis of Broca’s aphasia and 10 controls. Dependent measures of long pauses, short pauses and speech segment durations (ln) for each aphasic were converted to z scores by comparison with the control group. All of the Broca’s aphasics showed shorter mean speech segment durations than the control group. Nine cases produced significantly longer mean short pause durations. The results demonstrate that the FPS is a sensitive tool for characterisation of cognitive and motor processes associated with the impact of brain impairment on spontaneous speaking. It provides inferential statistics that quantify function across cognitive and motor domains beyond those provided by traditional categorical or model based diagnostic tools. References Hird K, Kirsner K (2010) Objective measurement of fluency in natural language production: A dynamic systems approach. Journal of Neurolinguistics. 23 (5): Special Issue: 518-530. Little, D., Oehmen, R., Dunn, J, Hird, K & Kirsner, K. (2012) Fluency Profiling System: An automated system for analyzing the temporal properties of speech. Behavioural Research. DOI 10.3758/s13428-012-0222-0 MacWhinney, B., Fromm, D., Forbes, M & Holland, A. (2011). AphasiaBank: Methods for studying discourse. Aphasiology, 25, 1286-1307 Thompson, C. K., & den Ouden, D. B. (2008). Neuroimaging and recovery of language in aphasia. Current Neurology and Neuroscience, 8(6), 475–483. Keywords: language measurement, fluency, Aphasia, speech science, validation of methods, natural language Conference: ACNS-2012 Australasian Cognitive Neuroscience Conference, Brisbane, Australia, 29 Nov - 2 Dec, 2012. Presentation Type: Poster Presentation Topic: Language Citation: Hird KM, Kirsner K, Little D, Oehmen R and Dunn J (2012). Objective automated analysis of natural language: The Fluency Profiling System as a measure of the efficiency of dynamic language networks.. Conference Abstract: ACNS-2012 Australasian Cognitive Neuroscience Conference. doi: 10.3389/conf.fnhum.2012.208.00045 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 25 Oct 2012; Published Online: 07 Nov 2012. * Correspondence: Prof. Kathryn M Hird, University of Notre Dame, Fremantle, WA, Australia, Kathryn.Hird@nd.edu.au Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Kathryn M Hird Kim Kirsner Daniel Little Raoul Oehmen John Dunn Google Kathryn M Hird Kim Kirsner Daniel Little Raoul Oehmen John Dunn Google Scholar Kathryn M Hird Kim Kirsner Daniel Little Raoul Oehmen John Dunn PubMed Kathryn M Hird Kim Kirsner Daniel Little Raoul Oehmen John Dunn Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Rehabilitation Targeted at Everyday Communication: Can We Change the Talk of People With Aphasia and Their Significant Others Within Conversation?

Wilkinson R, Wielaert S. Rehabilitation targeted at everyday communication: can we change the talk of people with aphasia and their significant others within conversation? Objective To investigate whether aphasia therapy can change the talk of speakers with aphasia and/or their significant others within conversation. Design Small number of intervention studies targeting conversations involving speakers with aphasia are reviewed. All are single case studies. Setting Key assessment in the studies was an audio or video recording of 1 or more conversations between the dyad, usually made in the home setting. Intervention in these studies took place in the participants' home or another setting, such as a therapy room. Participants In all of the studies reviewed, the participants consisted of a person with aphasia (PWA) and a significant other, usually the PWA's spouse. Interventions In all studies, therapy took the form of a behavioral intervention involving the provision of feedback to the significant other and/or PWA on their conversational behaviors uncovered by a conversation analysis assessment. Handouts, transcripts, discussion, and video feedback were used. Suggestions to permit participants to cope better with the effects of aphasia within conversation were given, and opportunities for practicing these strategies within conversation were provided. Main Outcome Measures Postintervention, 1 or more conversations involving the PWA and significant other were recorded in the same manner as the preintervention. Conversations were analyzed in relation to changes in the behaviors targeted in intervention, such as those involved in topic initiation or repair of linguistic errors. Results Each of the studies reviewed presented evidence that the talk of people with aphasia and/or their significant others can be changed in conversation. In some studies the evidence is primarily qualitative, in the form of observed changes to conversational behaviors postintervention. Some studies produce stronger evidence by combining qualitative and quantitative analyses of change. Conclusions There is evidence that intervention targeting conversations involving an aphasic speaker can achieve change. Future studies should move beyond single case designs, include more robust, quantifiable evidence of change, and provide evidence of maintenance of change.

Computer-mediated assessment of intelligibility in aphasia and apraxia of speech

Background: Previous work indicates that single-word intelligibility tests developed for dysarthria are sensitive to segmental production errors in aphasic individuals with and without apraxia of speech. However, potential listener learning effects and difficulties in adapting elicitation procedures to coexisting language impairments limit their applicability to left hemisphere stroke survivors. Aims: The main purpose of this study was to examine basic psychometric properties for a new monosyllabic intelligibility test developed for individuals with aphasia and/or AOS. A related purpose was to examine clinical feasibility and potential to standardise a computer-mediated administration approach. Methods & Procedures: A 600-item monosyllabic single-word intelligibility test was constructed by assembling sets of phonetically similar words. Custom software was used to select 50 target words from this test in a pseudo-random fashion, and to elicit and record production of these words by 23 speakers with aphasia and 20 neurologically healthy participants. To evaluate test–retest reliability, two identical sets of 50-word lists were elicited by requesting repetition after a live speaker model. To examine the effect of a different word set and auditory model, an additional set of 50 different words was elicited with a pre-recorded model. The recorded words were presented to normal-hearing listeners for identification via orthographic and multiple-choice response formats. To examine construct validity, production accuracy for each speaker was estimated via phonetic transcription and rating of overall articulation. Outcomes & Results: Recording and listening tasks were completed in less than 6 minutes for all speakers and listeners. Aphasic speakers were significantly less intelligible than neurologically healthy speakers and displayed a wide range of intelligibility scores. Test–retest and inter-listener reliability estimates were strong. No significant difference was found in scores based on recordings from a live model versus a pre-recorded model, but some individual speakers favoured the live model. Intelligibility test scores correlated highly with segmental accuracy derived from broad phonetic transcription of the same speech sample and a motor speech evaluation. Scores correlated moderately with rated articulation difficulty. Conclusions: We describe a computerised, single-word intelligibility test that yields clinically feasible, reliable, and valid measures of segmental speech production in adults with aphasia. This tool can be used in clinical research to facilitate appropriate participant selection and to establish matching across comparison groups. For a majority of speakers, elicitation procedures can be standardised by using a pre-recorded auditory model for repetition. This assessment tool has potential utility for both clinical assessment and outcomes research.

Real-time production of arguments and adjuncts in normal and agrammatic speakers

Two eyetracking experiments examined the real-time production of verb arguments and adjuncts in healthy and agrammatic aphasic speakers. Verb argument structure has been suggested to play an important role during grammatical encoding (Bock & Levelt, 1994) and in speech deficits of agrammatic aphasic speakers (Thompson, 2003). However, little is known about how adjuncts are processed during sentence production. The present experiments measured eye movements while speakers were producing sentences with a goal argument (e.g., the mother is applying lotion to the baby ) and a beneficiary adjunct phrase (e.g., the mother is choosing lotion for the baby ) using a set of computer-displayed written words. Results showed that the sentence production system experiences greater processing cost for producing adjuncts than verb arguments and this distinction is preserved even after brain-damage. In Experiment 1, healthy young speakers showed greater gaze durations and gaze shifts for adjuncts as compared to arguments. The same patterns were found in agrammatic and older speakers in Experiment 2. Interestingly, the three groups of speakers showed different time courses for encoding adjuncts: young speakers showed greater processing cost for adjuncts during speech, consistent with incremental production (Kempen & Hoenkamp, 1987). Older speakers showed this difference both before speech onset and during speech, while aphasic speakers appeared to preplan adjuncts before speech onset. These findings suggest that the degree of incrementality may be affected by speakers’ linguistic capacity.

Time reference in agrammatic aphasia: A cross-linguistic study

It has been shown across several languages that verb inflection is difficult for agrammatic aphasic speakers. In particular, Tense inflection is vulnerable. Several theoretical accounts for this have been posed, for example, a pure syntactic one suggesting that the Tense node is unavailable due to its position in the syntactic tree ( Friedmann & Grodzinsky, 1997); one suggesting that the interpretable features of the Tense node are underspecified ( Burchert, Swoboda-Moll, & De Bleser, 2005; Wenzlaff & Clahsen, 2004, 2005); and a morphosemantic one, arguing that the diacritic Tense features are affected in agrammatism ( Faroqi–Shah & Dickey, 2009; Lee, Milman, & Thompson, 2008). However recent findings ( Bastiaanse, 2008) and a reanalysis of some oral production studies (e.g. Lee et al., 2008; Nanousi, Masterson, Druks, & Atkinson, 2006) suggest that both Tense and Aspect are impaired and, most importantly, reference to the past is selectively impaired, both through simple verb forms (such as simple past in English) and through periphrastic verb forms (such as the present perfect, ‘has V-ed’, in English). It will be argued that reference to the past is discourse linked and reference to the present and future is not ( Zagona, 2003, in press). In-line with Avrutin’s (2000) theory that suggests discourse linking is impaired in Broca’s aphasia, the PAst DIscourse LInking Hypothesis (PADILIH) has been formulated. Three predictions were tested: (1) patients with agrammatic aphasia are selectively impaired in use of grammatical morphology associated with reference to the past, whereas, inflected forms which refer to the present and future are relatively spared; (2) this impairment is language-independent; and (3) this impairment will occur in both production and comprehension. Agrammatic Chinese, English and Turkish speakers were tested with the Test for Assessing Reference of Time (TART; Bastiaanse, Jonkers, & Thompson, unpublished). Results showed that both the English and Turkish agrammatic speakers performed as hypothesized, showing a selective deficit for production of inflected forms referring to the past, despite the typological difference between the languages. The Chinese agrammatic speakers were poor in reference to the past as well, but reference to the present and future also was severely impaired. For comprehension, the results were strikingly similar for the three languages: reference to the past was impaired for all. These results confirmed our hypothesis that reference to the past is discourse linked and, therefore, grammatical morphology used for reference to the past is impaired in agrammatic aphasia, whether this is done through Tense and/or Aspect markers.

Finding Levels of Abstraction in Speech Production

A widely held view in linguistics and psycholinguistics is that there are distinct levels of processing for context-independent and context-specific representations of sound structure. Recently, this view has been disputed, in part because of the absence of clear evidence that there are abstract mental representations of discrete sound-structure units. Here, we present novel evidence that separate context-independent and context-specific representations of sound structure are supported by distinct brain mechanisms that can be selectively impaired in individuals with acquired brain deficits. Acoustic data from /s/-deletion errors of 2 aphasic speakers suggest both a phonological level of processing at which sound representations (e.g., /p/) do not specify context-specific detail (e.g., aspirated or unaspirated) and a distinct level at which context-specific information is represented. These data help constrain accounts of sound-structure processing in word production and crucially support the claim that context-independent linguistic information affects language production.

Monologues and dialogues in aphasia: Some initial comparisons

Background: In recent years, there has been a shift in aphasia research interest from analysis of monologues to conversational dialogues. However, where monologic research has focused primarily on aspects such as language structure and quantity, conversational research has mainly focused on pragmatic aspects of discourse such as turn taking and repair. While there is some acknowledgement of the differences between language use in monologues and dialogues in aphasia, few comparisons have been made that cover a broad range of both syntactic and semantic aspects. Aims: This study aims to compare the discourse of aphasic speakers and non-brain-damaged control speakers in monologues and dialogues by using a range of syntactic and semantic analyses. In so doing, it aims to explore whether or not it is necessary for researchers and clinicians to sample both contexts in order to gain a full picture of a person's linguistic skills. Methods & Procedures: Two individuals with aphasia of varying severity provided monologues about their stroke experience, then participated in dialogues with a “significant other” on the same topic. Two control speakers, matched as closely as possible with the speakers with aphasia, undertook the same tasks, however they discussed a serious illness they had experienced. The SALT program (Miller & Iglesias, 2008) analysed the resulting data for syntactic productivity and complexity, and semantic analyses from a Systemic Functional Linguistic framework (Halliday & Matthiessen, 2004) were used to explore ideational, interpersonal, and textual meanings. Outcomes & Results: The syntactic measures demonstrated greater consistency across contexts, with the participants with aphasia using more and longer C-units in the monologue, although demonstrating more mazes in this context. The control speakers demonstrated slightly more variation but, like the speakers with aphasia, tended to use more words per C-unit in the monologue. Semantic measures demonstrated more variable patterns although some similarities also existed. Conclusions: The variation noted in the study supports the notion that clinicians and researchers should sample a variety of contexts in order to gain an overall picture of a person's language skills. Factors such as personality, topic, and conversation partner influence all seem to play a role in discourse production, particularly from the perspective of meanings conveyed. This study raises questions as to the actual effects of these factors on language structure and function and provides direction for future research in the area.

Taboo: A Novel Paradigm to Elicit Aphasia-Like Trouble-Indicating Behaviour in Normally Speaking Individuals

Two important research lines in neuro- and psycholinguistics are studying natural or experimentally induced slips of the tongue and investigating the symptom patterns of aphasic individuals. Only few studies have focused on explaining aphasic symptoms by provoking aphasic symptoms in healthy speakers. While all experimental techniques have so far dealt with the single word or the sentence level, the current study intended to provoke aphasia-like trouble-indicating behaviour (i.e. prepairs and repairs) in the spontaneous language production of unimpaired speakers. In their descriptions of complex pictures, the participants were requested to avoid particular words terming central elements of the pictures. The results show that the error pattern provoked by the novel "taboo" paradigm resembled substantially the pattern of aphasic individuals. Consequently, the paradigm is applicable for further studies, e.g. for bringing forward the understanding of spontaneous language production or for comparing the neurofunctional basis of errors in healthy and aphasic speakers.

Towards a quantitative measure of verbal effectiveness and efficiency in the Amsterdam-Nijmegen Everyday Language Test (ANELT)

Background: A well-known test for measuring verbal adequacy (i.e., verbal effectiveness) in mildly impaired aphasic speakers is the Amsterdam-Nijmegen Everyday Language Test (ANELT; Blomert, Koster, & Kean, 1995). Aphasia therapy practitioners score verbal adequacy qualitatively when they administer the ANELT to their aphasic clients in clinical practice. Aims: The current study investigated whether the construct validity of the ANELT could be further improved by substituting the qualitative score by a quantitative one, which takes the number of essential information units into account. The new quantitative measure could have the following advantages: the ability to derive a quantitative score of verbal efficiency, as well as improved sensitivity to detect changes in functional communication over time. Methods & Procedures: The current study systematically compared a new quantitative measure of verbal effectiveness with the current ANELT Comprehensibility scale, which is based on qualitative judgements. A total of 30 speakers of Dutch participated: 20 non-aphasic speakers and 10 aphasic patients with predominantly expressive disturbances. Outcomes & Results: Although our findings need to be replicated in a larger group of aphasic speakers, the main results suggest that the new quantitative measure of verbal effectiveness is more sensitive to detect change in verbal effectiveness over time. What is more, it can be used to derive a measure of verbal efficiency. Conclusions: The fact that both verbal effectiveness and verbal efficiency can be reliably as well as validly measured in the ANELT is of relevance to clinicians. It allows them to obtain a more complete picture of aphasic speakers' functional communication skills.

Comparison of machine learning methods for classifying aphasic and non-aphasic speakers

Abstract The performance of eight machine learning classifiers were compared with three aphasia related classification problems. The first problem contained naming data of aphasic and non-aphasic speakers tested with the Philadelphia Naming Test. The second problem included the naming data of Alzheimer and vascular disease patients tested with Finnish version of the Boston Naming Test. The third problem included aphasia test data of patients suffering from four different aphasic syndromes tested with the Aachen Aphasia Test. The first two data sets were small. Therefore, the data used in the tests were artificially generated from the original confrontation naming data of 23 and 22 subjects, respectively. The third set contained aphasia test data of 146 aphasic speakers and was used as such in the experiments. With the first and the third data set the classifiers could successfully be used for the task, while the results with the second data set were less encouraging. However, based on the results, no single classifier performed exceptionally well with all data sets, suggesting that the selection of the classifier used for classification of aphasic data should be based on the experiments performed with the data set at hand.

Halting Aphasic Interaction. Creation of Intersubjectivity and Spousal Relationship in Situ

This article discusses a communicative phenomenon that is relatively less studied: getting stuck in an aphasic conversation. Although aphasia as a medical and linguistic condition has been widely examined, the more social and participatory aspects of the symptom are not so well-known. Aphasia forms a threat to the emergence of a shared understanding, as well as to the experience of being in the shared, i.e., in the intersubjective, social world. In our analysis, we closely explore how understanding is constructed in the sequential organization of conversation. We use two data corpora when analysing the halting interaction. In our data, we detected two kinds of interactive halts that emerged in connection with aphasic word searching. First, 'real halts' were caused by the aphasic person's inability to find correct words and the co-participants were also not able to resolve the problem. Second, 'exam halts' occurred when the co-participant did not provide the missing words despite knowing what the aphasic speaker was trying to say. We discuss how this halting phenomenon is linked with the notions of intersubjectivity and face-work and conclude that real halts are more directly caused by the aphasic condition, whereas exam halts reflect the spousal relationship in the form of face-work.

The production and comprehension of verbs with alternating transitivity by patients with non-fluent aphasia

Background: Recent studies revealed that aphasic speakers have difficulties with the production of the intransitive (unaccusative) variant of verbs entering transitivity alternations. A key point of the current interpretations of these difficulties concerns the movement operations taking place at surface syntax, namely, the A-movement operation (Bastiaanse & van Zonneveld, 2005; Bastiaanse, 2008; Thompson, 2003). Aim: The present study revisits the issue of processing verbs with alternating transitivity in non-fluent aphasia in Greek, a language with rich morphology and relatively free word order, which lacks A-movement. In addition, in Greek, unaccusative verbs appear with different voice morphology: One class of intransitive variants of alternating verbs bears active morphology, another one non-active morphology and a third one can surface with both. The presence of non-active voice has been argued to correspond to the presence of a voice projection in syntax of these variants, while the variants that bear active morphology are not associated with a voice projection at the level of syntax. This study investigates the ability of non-fluent aphasic speakers to produce and comprehend verbs entering transitivity alterations and explores the role of active vs. non-active morphology and word order in the performance of aphasic speakers. Methods & Procedures: We tested five non-fluent patients and fifteen control participants. We used two tasks supported by pictures: an elicited production task and a comprehension task. The experimental material consisted of fifteen transitive and fifteen unaccusative verbs (marked for active, and/or non-active voice morphology) in sentence contexts. Outcomes & Results: The results indicated that (i) the aphasic speakers performed better on the production and comprehension of transitives than of unaccusatives, (ii) they showed significantly lower performance on the comprehension of unaccusatives with active morphology than on unaccusatives with non-active morphology, and finally (iii) they produced transitive (S)VO structures instead of the unaccusative ones. Conclusion: We suggest, in agreement with other researchers (for example, Schwartz, Linebarger, Saffran, & Pate, 1987) that aphasic individuals overuse a mapping strategy that associates the theta roles of agent and theme with syntactic subject and object respectively, as they produce transitive (S)VO structures, to a large extent, instead of unaccusatives. In addition, as they had difficulties with unaccusative verbs marked for active voice, we suggest that they could not successfully interpret unaccusative verbs with active voice morphology as non-agentive structures.

ERP Correlates of Word Production before and after Stroke in an Aphasic Patient

Changes in brain activity characterizing impaired speech production after brain damage have usually been investigated by comparing aphasic speakers with healthy subjects because prestroke data are normally not available. However, when interpreting the results of studies of stroke patients versus healthy controls, there is an inherent difficulty in disentangling the contribution of neuropathology from other sources of between-subject variability. In the present work, we had an unusual opportunity to study an aphasic patient with severe anomia who had incidentally performed a picture naming task in an ERP study as a control subject one year before suffering a left hemisphere stroke. The fortuitous recording of this patient's brain activity before his stroke allows direct comparison of his pre- and poststroke brain activity in the same language production task. The subject did not differ from other healthy subjects before his stroke, but presented major electrophysiological differences after stroke, both in comparison to himself before stroke and to the control group. ERP changes consistently appeared after stroke in a specific time window starting about 250 msec after picture onset, characterized by a single divergent but stable topographic configuration of the scalp electric field associated with a cortical generator abnormally limited to left temporal posterior perilesional areas. The patient's pattern of anomia revealed a severe lexical-phonological impairment and his ERP responses diverged from those of healthy controls in the time window that has previously been associated with lexical-phonological processes during picture naming. Given that his prestroke ERPs were indistinguishable from those of healthy controls, it seems highly likely that the change in his poststroke ERPs is due to changes in language production processes as a consequence of stroke. The patient's neurolinguistic deficits, combined with the ERPs results, provide unique evidence for the role of left temporal cortex in lexical-phonological processing from about 250 to 450 msec during word production.