Training verb and sentence production in agrammatic Broca's aphasia

Background: Many aphasic speakers have problems producing verbs at both the word and the sentence level. A treatment programme called ACTION (Bastiaanse, Bunge, & Perk, 2004 Bastiaanse, R., Bunge, F. and Perk, Y. 2004. Action: Ein Therapieprogramm mit Verben auf Wort-. und Satzebene, Hofheim, , Germany: NAT-Verlag.  [Google Scholar]; Bastiaanse, Jonkers, Quak, & Varela Put, 1997 Bastiaanse, R., Jonkers, R., Ch, Quak and Varela Put, M. 1997. Werkwoordproductie op Woord- en Zinsniveau (Verb production at the word and sentence level), Lisse, , The Netherlands: Swets Test Publishers.  [Google Scholar]) has been developed to train verb production of both fluent and non-fluent aphasic speakers. It consists of four levels: single verbs, filling in infinitives, filling in finite verbs, and sentence construction. For the present study the efficacy of the programme for agrammatic speakers with Broca's aphasia was tested.

Aims: The aim of the study was to measure the effects of treatment with ACTION on non-trained infinitives and finite verbs, and to analyse the generalisation effects on spontaneous speech and verbal communication in daily life.

Methods & Procedure: ACTION was used to train 11 agrammatic patients with Broca's aphasia, following the multiple baseline across behaviours design. The patients were tested weekly on untreated items. Two follow-up assessments were done, 1 and 3 months post-treatment. Generalisation to related and unrelated materials was measured with subtasks of the Aachen Aphasia Test (AAT). Spontaneous speech was analysed, and verbal communication was measured before and after treatment and 3 months post-treatment by the Amsterdam-Nijmegen Everyday Language Test (ANELT).

Outcomes & Results: There was improvement on the untrained infinitives and finite verbs. The improvement on infinitives was relatively minor; finite verbs, which were more impaired than the infinitives prior to treatment, improved up to the level of the infinitives. The improvement generalised to the related tasks of the AAT, but not to the unrelated task; verbal communication improved significantly. This improvement was reflected in relevant variables of spontaneous speech (mean length of utterances, proportion of finite verbs and verb diversity), but not in an unrelated variable (diversity of nouns).

Conclusions: Treatment with ACTION resulted in better production of finite verbs. The effects generalised to spontaneous speech. Most importantly, it was shown that communication in daily life improved.     

Errorless and errorful therapy for verb and noun naming in aphasia

Background: The aphasiological literature has provided an extensive body of research on verb impairments but many fewer verb therapy studies. Verbs display particular complexity at various levels of linguistic analysis: phonological, morphological, semantic, and syntactic. Verb impairments can arise at any of these processing levels as well as from cognitive sources. Verb-naming therapies may therefore be relatively more vulnerable to errors, which could reduce their effectiveness. Errorless learning has been used with positive results for noun therapies.

Aims: Given the high linguistic and cognitive demands of verb processing, this study investigated whether errorless therapy would be more effective for verb naming than more traditional hierarchical cueing (relatively errorful) therapy.

Methods & Procedures: Nine participants with word-finding difficulties as a part of their chronic aphasia took part in the study.

Outcomes & Results: For the dependent variable of naming accuracy, as in previous studies, we found that errorless therapy was as effective as errorful therapy for both verb and noun naming. Three participants with most severe aphasia showed significantly greater gains in noun as opposed to verb naming. The remaining participants exhibited comparable gains in both nouns and verb naming. There was no lasting generalisation from treated to untreated therapy items. The prediction that errorless therapy would be more effective for verb naming was not upheld; errorless and errorful approaches were as effective as one another.

Conclusions: An errorless-learning approach to verb and noun naming was a time-efficient therapy, and one that was as effective as an errorful/hierarchical cueing method in improving naming accuracy, for a range of participants with varying naming skills and types of aphasia.     

A comparison of word versus sentence cues as therapy for verb naming in aphasia

Background: Improving verb naming in people with aphasia should enable expession of a wider range of sentence types and meanings, and may have wider benefits for connected speech. Estableshing the optimal therapy methods for improving verb naming is, therefore, of substantial clinical importance.

Aims: This study investigated whether cueing sentence production would improve verb‐naming accuracy to a greater extent than the more typical, single‐word verb‐cueing therapies. A second aim was to examine the extent to which verb picture naming improvements would generalise to naming of the same items in dynamic videos.

Methods & Procedures: Seven participants with chronic aphasia including word retrieval impairment took part in a case‐series study. Decreasing cues were used to devise two therapies to improve verb naming: word cue therapy and sentence cue therapy. A total of 60 verbs that had not been named accurately in baseline testing on three presentations were collated for each participant. These were split into three sets of 20 verbs: set A was used in word cue therapy, set B in sentence cue therapy, and set C served as control items undergoing no therapy. The sets were matched for significant psycholinguistic variables such as word frequency, imageability, length, and number of noun arguments. Therapy consisted of 10 sessions over 5 weeks. Post‐therapy assessments consisted of an immediate naming assessment (1 week following therapy) and a follow‐up assessment 5 weeks later. Naming of the target verbs in set A for each participant was also assessed using a dynamic video presentation.

Outcomes & Results: Both therapies resulted in highly significant gains in naming accuracy for treated verbs with little, if any, carry‐over to untreated verbs. There were no significant differences between the therapies for individual participants. At the group level there was a significantly greater benefit for word cue over sentence cue therapy at the follow‐up naming assessment. The gains in verb naming post therapy generalised from the static depictions used in therapy to naming of the same items in the dynamic video presentation format.

Conclusions: Both word and sentence cue therapy for verb naming were effective in improving naming accuracy. Gains from word cue therapy can generalise to naming of very different exemplars of the same verb targets. Word cue therapy resulted in significantly greater gains than sentence cues at the level of the group, but the difference was not substantial enough to be significant at the individual participant level. Generalisation, as an effect following intervention, can be examined in terms of naming different exemplars of a word, as well as its more typical meaning of generalisation from treated to untreated items in therapy.     

Retrieval of instrumental verbs in aphasia: An explorative study

Retrieval of instrumental verbs in two conditions in two Broca and two anomic patients was studied. The instrumental verbs were divided into two classes, viz. instrumental verbs that are related in name with the instrument (e.g. to saw-a saw) and those that are not related in name (e.g. to write-a pen). The actions had to be named (a) in isolation and (b) in a sentence. Two Broca and two anomic patients were examined on both subtests. Although the raw scores on the two subtests do not reveal large differences between the four aphasic subjects, distinguishing the two classes of instrumental verbs and performing an error analysis shows that a different deficit underlies the difficulties of Broca's and anomic aphasics.     

Verbal memory and sentence comprehension in aphasia: A case series

ABSTRACT

This case series explores the relationship between verbal memory capacity and sentence comprehension in four patients with aphasia. Two sentence comprehension tasks showed that two patients, P1 and P2, had impaired syntactic comprehension, whereas P3 and P4’s sentence comprehension was intact. The memory assessment tasks showed that P1 and P2 had severely impaired short-term memory, whereas P3 and P4 performed within the normal range in the short-term memory tasks. This finding suggests an association between short-term memory deficit and sentence comprehension difficulties. P1 and P3 exhibited impaired comparable working memory deficits, suggesting a dissociation between working memory and sentence comprehension.     

Noun and verb differences in picture naming: Past studies and new evidence

We re-examine the double dissociation view of noun-verb differences by critically reviewing past lesion studies reporting selective noun or verb deficits in picture naming, and reporting the results of a new picture naming study carried out with aphasic patients and comparison participants.Since there are theoretical arguments and empirical evidence that verb processing is more demanding than noun processing, in the review we distinguished between cases that presented with large and small differences between nouns and verbs. We argued that the latter cases may be accounted for in terms of greater difficulty in processing verbs than nouns. For the cases reporting large differences between nouns and verbs we assessed consistency in lesion localization and consistency in diagnostic classification. More variability both in terms of diagnostic category and lesion sites was found among the verb impaired than the noun impaired patients.In the experimental study, nine aphasic patients and nine age matched neurologically unimpaired individuals carried out a picture naming study that used a large set of materials matched for age of acquisition and in addition to accuracy measures, latencies were also recorded. Despite the patients' variable language deficits, diagnostic category and the matched materials, all patients performed faster and more accurately in naming the object than the action pictures. The comparison participants performed similarly. We also carried out a qualitative analysis of the errors patients made and showed that different types of errors were made in response to object and action pictures. We concluded that action naming places more and different demands on the language processor than object naming.The conclusions of the literature review and the results of the experimental study are discussed in relation to claims previous studies have made on the basis of the double dissociation found between nouns and verbs. We argue that these claims are only justified when it can be shown that the impairments to the two categories occur for the same underlying reason and that the differences between the two categories are large.     

What goes wrong during passive sentence production in agrammatic aphasia: An eyetracking study

Background: Production of passive sentences is often impaired in agrammatic aphasia and has been attributed both to an underlying structural impairment (e.g., Schwartz, Saffran, Fink, Myers, & Martin, 1994 Schwartz, M. F., Saffran, E. M., Fink, R. B., Myers, J. L. and Martin, N. 1994. Mapping therapy: A treatment program for agrammatism. Aphasiology, 8: 19–54. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) and to a morphological deficit (e.g., Caplan & Hanna, 1998 Caplan, D. and Hanna, J. 1998. Sentence production by aphasic patients in a constrained task. Brain and Language, 63: 184–218. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]; Faroqi-Shah & Thompson, 2003 Faroqi-Shah, Y. and Thompson, C. K. 2003. Effect of lexical cues on the production of active and passive sentences in Broca's and Wernicke's aphasia. Brain and Language, 85: 409–426. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). However, the nature of the deficit in passive sentence production is not clear due to methodological issues present in previous studies.

Aims: This study examined active and passive sentence production in nine agrammatic aphasic speakers under conditions of structural priming using eyetracking to test whether structural impairments occur independently of morphological impairments and whether the underlying nature of error types is reflected in on-line measures, i.e., eye movements and speech onset latencies.

Methods & Procedures: Nine participants viewed and listened to a prime sentence in either active or passive voice, and then repeated it aloud. Next, a target picture appeared on the computer monitor and participants were instructed to describe it using the primed sentence structure.

Outcomes & Results: Participants made substantial errors in sentence structure, i.e., passives with role reversals (RRs) and actives-for-passives, but few errors in passive morphology. Longer gaze durations to the first-produced noun for passives with RRs as compared to correct passives were found before and during speech. For actives-for-passives, however, this pattern was found during speech, but not before speech.

Conclusions: The deficit in passive sentence production does not solely arise from a morphological deficit, rather it stems, at least in part, from a structural level impairment. The underlying nature of passives with RRs is qualitatively different from that of actives-for-passives, which cannot be clearly differentiated with off-line testing methodology.     

Positive effects of a computerised working memory and executive function training on sentence comprehension in aphasia

Aphasia, the language disorder following brain damage, is frequently accompanied by deficits of working memory (WM) and executive functions (EFs). Recent studies suggest that WM, together with certain EFs, can play a role in sentence comprehension in individuals with aphasia (IWA), and that WM can be enhanced with intensive practice. Our aim was to investigate whether a combined WM and EF training improves the understanding of spoken sentences in IWA. We used a pre–post-test case control design. Three individuals with chronic aphasia practised an adaptive training task (a modified n-back task) three to four times a week for a month. Their performance was assessed before and after the training on outcome measures related to WM and spoken sentence comprehension. One participant showed significant improvement on the training task, another showed a tendency for improvement, and both of them improved significantly in spoken sentence comprehension. The third participant did not improve on the training task, however, she showed improvement on one measure of spoken sentence comprehension. Compared to controls, two individuals improved at least in one condition of the WM outcome measures. Thus, our results suggest that a combined WM and EF training can be beneficial for IWA.     

The curious case of processing unaccusative verbs in aphasia

Background: Individuals with agrammatic Broca’s aphasia (IWBA) exhibit a delay in lexical activation in S-V-O word order sentences and delayed lexical reactivation in sentences that contain syntactic dependencies. This pattern is in contrast to neurologically unimpaired individuals who immediately evince lexical reactivation at the gap in sentences that contain syntactic dependencies. However, in the case of sentences that contain unaccusative verbs, neurologically unimpaired individuals also exhibit a delay in lexical reactivation. This delay provides a unique opportunity to further examine lexical delays in IWBA.

Aim: The purpose of the current studies is to investigate the online comprehension of sentences that contain unaccusative verbs in IWBA and in a group of age-matched control (AMC) individuals.

Methods and Procedures: Cross-modal picture priming was used to test for priming of a displaced lexical item (direct object noun) immediately after the unaccusative verb (at the gap) during the ongoing auditory stream and at three additional time points downstream from the verb (500 ms, 750 ms, and 1,250 ms).

Outcomes and Results: Delayed reactivation of the displaced lexical item downstream from the gap (similar to prior reports of delayed reactivation with younger unimpaired listeners) for both the AMCs and the IWBA was found.

Conclusion: These results provide support that IWBA do not evince a delayed time course of lexical reactivation for unaccusative verbs compared to neurologically unimpaired individuals.     

Context effects on verb production in specific language impairment (SLI): Confrontation naming versus connected speech

A handful of studies have shown that verbs are more vulnerable than nouns to retrieval deficits on picture-based naming tasks for children with specific language impairment (SLI). The aim of this study was to examine if the disproportionate verb as opposed to noun production deficit reported for naming is also found in connected speech. Sixteen children participated in the study: eight children diagnosed with SLI (mean age: 6:3 years) and eight typically language developing (TLD, mean age: 5:9 years) controls. Verb and noun production was measured in connected speech and compared to picture confrontation naming. Both groups of children showed a significant difficulty naming verbs compared to nouns. In contrast, they did not differ on the total number of both verb tokens and verb types produced in connected speech. The findings indicate that the previously reported verb retrieval difficulties in SLI are a product of the confrontation naming task demands rather than a true verb deficit.     

Training verb argument structure production in agrammatic aphasia: Behavioral and neural recovery patterns

Introduction

Neuroimaging and lesion studies indicate a left hemisphere network for verb and verb argument structure processing, involving both frontal and temporoparietal brain regions. Although their verb comprehension is generally unimpaired, it is well known that individuals with agrammatic aphasia often present with verb production deficits, characterized by an argument structure complexity hierarchy, indicating faulty access to argument structure representations for production and integration into syntactic contexts. Recovery of verb processing in agrammatism, however, has received little attention and no studies have examined the neural mechanisms associated with improved verb and argument structure processing. In the present study we trained agrammatic individuals on verbs with complex argument structure in sentence contexts and examined generalization to verbs with less complex argument structure. The neural substrates of improved verb production were examined using functional magnetic resonance imaging (fMRI).

Methods

Eight individuals with chronic agrammatic aphasia participated in the study (four experimental and four control participants). Production of three-argument verbs in active sentences was trained using a sentence generation task emphasizing the verb's argument structure and the thematic roles of sentential noun phrases. Before and after training, production of trained and untrained verbs was tested in naming and sentence production and fMRI scans were obtained, using an action naming task.

Results

Significant pre- to post-training improvement in trained and untrained (one- and two-argument) verbs was found for treated, but not control, participants, with between-group differences found for verb naming, production of verbs in sentences, and production of argument structure. fMRI activation derived from post-treatment compared to pre-treatment scans revealed upregulation in cortical regions implicated for verb and argument structure processing in healthy controls.

Conclusions

Training verb deficits emphasizing argument structure and thematic role mapping is effective for improving verb and sentence production and results in recruitment of neural networks engaged for verb and argument structure processing in healthy individuals.     

A method for studying the evolution of naming error types in the recovery of acute aphasia: a single-patient and single-stimulus approach

In this study, we present a method for analysing the evolution of picture naming errors in the follow-up of single patients affected by acute aphasia. In particular, we have based our analysis on the presence of response type inconsistency, as patients often fail to give the same type of response to the same stimulus at a task repetition attempted after a short time. Due to the uncertain definition of the type of response associated to a given stimulus for each stage of the clinical course, the investigation of the factors underlying the transition between different types of response is a serious methodological challenge. The solution presented here is based on a multiple presentation of the same naming battery at different stages of the clinical course, on the estimation of the probability associated with each response type at each stage, and on the estimation of the transition probability between different response types from one clinical stage to another. The basic idea was to use the set of probabilities referred to above as single stimuli weights in the study of linear models; these permit to compare different types of responses and different types of transitions. We present the application of this method to the study of a single case, a woman affected by fluent aphasia examined twice in the first 2 weeks following stroke. Besides discussing empirical findings, we comment on the usefulness of this method for wider fields of inquiry.     

The comprehension of sentences with unaccusative verbs in aphasia: a test of the intervener hypothesis

Background: It is well accepted that individuals with agrammatic Broca’s aphasia have difficulty comprehending some sentences with filler-gap dependencies. While investigations of these difficulties have been conducted with several different sentence types (e.g., object relatives, Wh-questions), we explore sentences containing unaccusative verbs, which arguably have a single noun phrase (NP) that is base-generated in object position but then is displaced to surface subject position. Unaccusative verbs provide an ideal test case for a particular hypothesis about the comprehension disorder—the Intervener Hypothesis—that posits that the difficulty individuals with agrammatic Broca’s aphasia have comprehending sentences containing filler-gap dependencies results from similarity-based interference caused by the presence of an intervening NP between the two elements of a syntactic chain.

Aim: To assess a particular account of the comprehension deficit in agrammatic Broca’s aphasia—the Intervener Hypothesis.

Methods & Procedures: We used a sentence–picture matching task to determine if listeners with agrammatic Broca’s aphasia (LWBA) and age-matched neurologically unimpaired controls (AMC) have difficulty comprehending unaccusative verbs when placed in subject relative and complement phrase (CP) constructions.

Outcomes & Results: We found above-chance comprehension of both sentence constructions with the AMC participants. In contrast, we found above-chance comprehension of CP sentences containing unaccusative verbs but poor comprehension of subject relative sentences containing unaccusative verbs for the LWBA.

Conclusions: These results provide support for the Intervener Hypothesis, wherein the presence of an intervening NP between two elements of a filler-gap dependency adversely affects sentence comprehension.     

Treatment of written verb and written sentence production in an individual with aphasia: A clinical study

Background: Although the efficacy of treatments for spoken verb and sentence production deficits in aphasia has been documented widely, less is known about interventions for written verb and written sentence production deficits.

Aims: This study documents a treatment aiming to improve production of (a) written subject-verb sentences (involving intransitive verbs) and (b) written subject-verb-object sentences (involving transitive verbs).

Methods & Procedures: The participant, a 63-year-old female aphasic speaker, had a marked language comprehension deficit, apraxia of speech, relatively good spelling abilities, and no hemiplegia. The treatment involved intransitive verbs producing subject-verb active sentences and transitive verbs producing subject-verb-object active non-reversible sentences. The treatment was undertaken in the context of current UK clinical practice.

Outcomes & Results: Statistical improvements were noted for the trained sets of verbs and sentences. Other improvements were also noted in LW's ability to retrieve some non-treated verbs and construct written sentences. Treatment did not generalise to sentence comprehension and letter spelling to dictation.

Conclusions: Our participant's ability to write verbs and sentences improved as a result of the treatment.     

A comparison of drawing and writing on facilitating word retrieval in individuals with aphasia

ABSTRACT

Background: Drawing has long been a focus in aphasia research as a compensatory strategy for improving functional communication in individuals with aphasia, but fewer studies have addressed drawing as a facilitative tool to improve their verbal output.

Aims: The purpose of the current study was to investigate differences in naming accuracy in individuals with aphasia during a drawing versus a writing condition. Two research questions were formed to examine the role of drawing in facilitating naming: 1) Will participants perform better when naming with drawing compared to confrontation naming only or when naming with writing? and 2) Is the quality of the picture drawn related to the naming accuracy?

Methods & Procedures: Across three separate one-hour sessions, fifteen individuals with aphasia (n = 15) aged 44–81 years (M = 61.47, SD = 13.27) were evaluated using two standardized language assessments, the Western Aphasia Battery-Revised and Pyramid and Palm Tree Test, and three naming tasks designed to assess the effect of writing and drawing on naming performance. The three naming conditions consisted of confrontation naming only, naming with drawing, and naming with writing.

Outcomes & Results: A one-way, repeated measures analysis of variance (ANOVA) was computed to analyze the impact of naming conditions on the participants’ naming accuracy. The main effect of naming conditions was statistically significant, F (1, 14) = 5.87, p < 0.05, and Bonferroni correction revealed that the participants performed significantly better in the naming with drawing condition than with writing condition. In addition, no correlation between the quality of the pictures drawn and the participants’ naming performance was found which suggested that the quality of drawing did not affect the accuracy of naming.

Conclusions: When attempting to name a picture along with drawing its representation, the act of drawing may facilitate word retrieval by stimulating the semantic network associated with the word and involving the right cerebral hemisphere in the word retrieval process. Through drawing, these semantic features of the target word are more strongly activated than other related words. When the semantic features are more strongly activated, the probabilities of retrieving the target word may increase. In contrast, writing heavily relies on the left hemisphere and linguistic systems. Thus, naming when attempting to write the associated word may be a more cognitively and linguistically demanding task for individuals with aphasia.     

Effects of verb bias and syntactic ambiguity on reading in people with aphasia

Background: The Lexical Bias Hypothesis claims that people with aphasia (PWA) have difficulty understanding sentences when the verb’s argument structure bias conflicts with the sentence structure. This hypothesis can account for comprehension deficits that affect simple sentences, but the role of verb bias has not been clearly demonstrated in temporarily ambiguous sentences.

Aims: This study examined how verb bias affects comprehension of temporarily ambiguous and unambiguous sentences using self-paced reading.

Methods & Procedures: PWA and controls read sentences that contained sentential complements (e.g., The talented photographer accepted (that) the fire could not have been prevented). The main verb was biased to take a direct object (e.g., accepted) or a sentential complement (e.g., admitted). In addition, the sentential complement was either introduced by the complementiser that (i.e., unambiguous) or unmarked (i.e., ambiguous).

Results: The reading times of PWA were affected more by verb bias than by the presence of the complementiser, whereas the control group’s reading times were more affected by the presence or absence of the complementiser.

Conclusions: The results were generally consistent with the Lexical Bias Hypothesis, and showed that a mismatch between verb bias and sentence structure affected the processing of unambiguous and temporarily ambiguous sentences in PWA.     

Effects of impairment-based individual and socially oriented group therapies on verb production in aphasia

Purpose: Two philosophies of intervention exist in aphasia rehabilitation: impairment-based approaches and socially oriented approaches. Both approaches have been shown to improve communication in persons with aphasia, but no studies have directly compared the effects of each approach or a combined approach on a targeted linguistic skill. This article explores the effects of individual and group therapies used both in isolation and in combination on verb production in aphasia.

Methods: Twelve individuals with chronic aphasia were trained on transitive verbs under three conditions—individual, group and combined—over a 6-week interval. Treatment was counterbalanced across subject and training groups. A delayed-treatment, within-participant design was used. Verb probe data were collected at 10 points throughout the study. Language measures were taken at two intervals pre- and two intervals post-treatment. Functional, narrative and quality-of-life measures were taken once pre- and once post-treatment.

Results: Significant change was observed on linguistic, functional communication and quality-of-life measures. There was no significant effect of treatment condition.

Conclusions: The results provide evidence of linguistic and psychosocial change in individuals with chronic aphasia following this treatment. Results failed to find that one treatment condition was superior to others.