Ruth Herbert

Phonological therapy for word-finding difficulties: A re-evaluation

Background: Treatments for word-finding difficulties in aphasia using semantic techniques have been shown to be effective (e.g., Marshall, Pound, White-Thomson, & Pring, 1990). The evidence with regard to phonological treatment is more equivocal, however, with some studies reporting only short-term improvement in word retrieval (e.g., Howard, Patterson, Franklin, Orchard-Lisle, & Morton, 1985a) and other studies reporting lasting effects (e.g., Miceli, Amitrano, Capasso, & Caramazza, 1996). There is also little in the literature on the use of orthographic cues in treatment (Howard & Harding, 1998). Additionally, whereas several studies have reported the results of using cues in facilitation of word-finding difficulties (e.g., Patterson, Purrell, & Morton, 1983), none so far has attempted to relate response to facilitation and response to treatment using similar techniques in the same individuals. Aims: This study set out to investigate whether the use of phonological and orthographic cues in the treatment of word-finding difficulties could produce lasting improvements in word retrieval. The response of the participants to phonological and orthographic cues in a facilitation study was also related to their response to treatment using similar cues. Methods & Procedures: The study used a case series design. The participants were eight people with acquired aphasia who were all at least 1 year post-onset, had a single left CVA, and had word-finding difficulties as a significant aspect of their aphasia. Detailed assessment of each participant was carried out to identify the nature of their word-finding difficulties and this was related to response to treatment. Outcomes & Results: Results are given for the eight participants, seven of whom benefited overall from treatment. Both phonological and orthographic cues were effective in improving word retrieval. For the group as a whole there was a significant correlation between the overall outcome of facilitation and response to treatment.

Do picture‐naming tests provide a valid assessment of lexical retrieval in conversation in aphasia?

Background: Word‐finding problems commonly occur in aphasia and can significantly affect communication. Assessment of this deficit typically involves naming pictures. However, this method has been criticised as lacking ecological validity. Alternative methods include the measurement of lexical retrieval in narration or conversation, although few published studies have quantified word finding in the latter. Aims: We aimed to identify a reliable and valid assessment of lexical retrieval in conversation, and to elucidate the nature of the relationship between lexical retrieval in picture naming and in conversation. Methods and Procedures: We developed a quantitative measure of word finding in conversation in aphasia and established the reliability and stability of the method. We compared the scores of a group of people with aphasia on this measure with their scores on a picture‐naming test. Outcomes and Results: We found significant relationships between picture‐naming scores and a number of key variables analysed in the conversation measure. We propose that scores on picture naming relate to the ability to retrieve nouns in everyday conversation for the people with aphasia who took part in this study. Conclusions: The use of picture‐naming tasks is justified, providing a valid and rich means of assessment of lexical retrieval. Further research is required to replicate these results with more people with aphasia. We offer the quantitative assessment of conversation developed here for use in research and clinical spheres.

Phonological and orthographic facilitation of word-retrieval in aphasia: Immediate and delayed effects

In the literature on repetition priming of word-production in normal participants, long-lasting effects can be found from a single prime. This contrasts with the findings with adults with anomia (as part of their aphasia) where phonological cues, such as first sound or rhyme, have been shown to have very short-lasting effects on word retrieval (Patterson, Purell, & Morton, 1983). In addition, the research into treatment of anomia suggests that semantic techniques produce longer-lasting effects than phonological techniques (Howard et al., 1985b). One difference between phonological and semantic techniques is in the element of choice available. Typically phonological cues are simply provided. This contrasts with semantic techniques where a choice is available, for example selecting from a set of pictures to match a word. This study, using a case series design, set out to replicate the finding, that phonological techniques have only short-lasting effects on word retrieval in aphasia and to investigate the influence of providing a choice of cues. Items that participants with aphasia were unable to name after 5 seconds were allocated to one of three conditions: extra time (control condition), single cue, and choice of two cues. Naming was assessed immediately and at a delay (over 10 minutes later). Four different cue types were used: whole word, spoken CV, written CV, and rime. The results were surprising. The cues influenced immediate naming, as predicted. However, this effect was still significant a delayed naming. Additionally, the benefits from a choice of cues were generally similar to those from a single cue. Different patterns of cue effectiveness were found for different participants. Further investigations shed some light on the mechanisms of cueing, orthographic cueing in particular.

Combining lexical and interactional approaches to therapy for word finding deficits in aphasia

Background: There are two distinct theoretical positions underlying approaches to aphasia therapy. The first addresses the language impairment directly through tasks designed to improve performance in that language function. This form of therapy was employed in a related study involving the participants reported here (Hickin et al., 2002a). The second seeks to bypass the language impairment by, for example promoting alternative forms of communication, and stressing the importance of successful rather than normal communication. There are few studies that combine the structured principled methods of the first with the ecologically valid basis of the second approach. Aims: Our aim was to investigate the effectiveness of combining a lexical therapy, targeting a discrete set of items and using cues to prompt name retrieval, with communicative use of those items, in tasks ranging from naming to definition through to structured conversation. We investigated the effects of the therapy in terms of gains in picture naming, and performance in a task simulating communication situations (production of nouns in everyday communication). Methods & Procedures: The study is a case series design involving six people with aphasia. All were adult English speakers aged 39 and upwards who were aphasic following a single left hemisphere stroke. Picture naming and production of nouns in everyday communication was assessed prior to and after therapy. Outcomes & Results: The combined therapy described here was effective for five of the six participants in terms of gains in picture naming, and an increase in communicatively effective responses in the noun production task. One person, for whom the lexical therapy described in Hickin et al. (2002a) was not effective, did however respond to the therapy reported here. For one of the six participants, the therapy was not effective. Conclusions: Therapy that targets a specific set of words, and encourages their use in tasks approaching everyday communication, can be effective in improving word finding in picture naming and in a functional speech task. As therapy effects are restricted to items undergoing therapy on the whole it is essential that words are selected for therapy on the basis of their functional use to the participant. This therapy was effective for most of the six participants and we are unable at this stage to identify exclusion criteria for undergoing this therapy.

Aphasia rehabilitation: Does generalisation from anomia therapy occur and is it predictable? A case series study

INTRODUCTION The majority of adults with acquired aphasia have anomia which can respond to rehabilitation with cues. However, the literature and clinical consensus suggest change is usually limited to treated items. We investigated the effect of an experimentally controlled intervention using progressive cues in the rehabilitation of noun retrieval/production in 16 participants with chronic aphasia. METHOD Participants were sub-divided relative to the group according to performance on semantic tasks (spoken/written word to picture matching) and phonological output processing (presence/absence of word length effect and proportion of phonological errors in picture naming) in order to investigate outcome in relation to language profile. Cueing therapy took place weekly for 8 weeks. RESULTS Intervention resulted in significant improvement on naming treated items for 15/16 participants, with stable performance on control tasks. Change occurred at the point of intervention and not during pre-therapy assessments. We predicted particular patterns of generalisation which were upheld. Only participants classified as having relatively less of a semantic difficulty and more of a phonological output deficit demonstrated generalisation to untreated items. Outcome did not relate to traditional aphasia classification. CONCLUSION A cueing hierarchy can improve word retrieval/production for adults with aphasia. In some cases generalisation to untreated items also occurs. The study demonstrates that the results of behavioural testing can be used to guide predictions of recovery with intervention.

A controlled study of changes in conversation following aphasia therapy for anomia

This paper investigates the relationship between change in picture naming with anomia therapy and changes in word retrieval in conversations between adults with aphasia and a regular conversational partner. We present data from two therapy projects (Hickin et al. [1] and Best et al. [2]). In each study, therapy involved cueing with the aim of improving retrieval of a set of nouns. Naming of the experimental items was assessed twice prior to therapy and again immediately afterwards. There was a significant change in word finding, as measured by picture naming, for the group and for 11 of the 13 participants. At the same time points, we collected conversations between the person with aphasia and a regular conversational partner. We analysed these using Profile of Word Errors and Retrieval in Speech (Herbert et al. [3]) and investigated a set of conversational variables predicted to change with therapy. Unsurprisingly, the conversation data is not straightforward. There is no significant change on the conversation measures for the group but some changes for individuals. We predicted change in word retrieval after therapy would relate to change in everyday conversations and tested this by correlating the change (post-therapy minus mean pre-therapy) in picture naming with the change in conversation variables. There was a significant positive relationship between the change in picture naming and change in some conversation measures including the number of nouns produced in 5 min of conversation (r = 0.50, p < 0.05, one-tailed) and the number of nouns produced per substantive turn (r = 0.55, p < 0.05, one-tailed). The findings suggest changes in word finding following therapy for aphasia can be reflected in changes in conversation. The clinical implications of the complex results are explored.

The role of noun syntax in spoken word production: Evidence from aphasia

We describe MH who presents with agrammatic aphasia and anomia, and who produces semantic errors in the absence of a central semantic impairment. This pattern of performance implies damage to syntactic processes operating between semantics and phonological output. Damage here may lead to lexical selection errors and a deficit in combining words to form phrases. We investigated MHs knowledge and processing of noun syntax in mass and count nouns. She produced more count nouns than mass nouns. She showed impaired knowledge of noun syntax in judgement tasks and production tasks, with mass noun syntax being more impaired than count. We interpret these results in terms of a two-stage model of lexical retrieval. We propose that syntactic information represented at the lemma level is activated even in bare noun production, and can be differentially impaired across noun categories. That same damage can lead to semantic errors in production. For MH limited syntactic options are available to support production, and these favour count noun production. The data provide a new account of output semantic errors.

Treatment of word retrieval in aphasia: generalisation to conversational speech.

The question of whether treatment gains in picture naming generalise to conversation remains relatively unexplored. Several difficulties surround data collection and analysis. A quantitative measure of word retrieval in aphasia is presented along with relevant details relating to the reliability of the measure, and the relationship between word retrieval in picture naming and noun retrieval in conversation. We discuss the clinical application of the measure and its applicability outside the field of aphasia.

PHONOLOGICAL AND ORTHOGRAPHIC APPROACHES TO THE TREATMENT OF WORD RETRIEVAL IN APHASIA

We present a preliminary report on a study of the treatment of word finding difficulties in aphasia using phonological and orthographic cues. These techniques although often used to cue word finding in the immediate term have been little evaluated in terms of therapy designed to improve word retrieval in the long term. The first phase using cued word retrieval in a picture naming task was followed by a second phase designed to facilitate use of treated words in real-life contexts. The results from both phases were encouraging with improved word retrieval for three out of the four participants. The implications for clinical practice are discussed.

A Normative Database and Determinants of Lexical Retrieval for 186 Arabic Nouns: Effects of Psycholinguistic and Morpho-Syntactic Variables on Naming Latency.

Research into lexical retrieval requires pictorial stimuli standardised for key psycholinguistic variables. Such databases exist in a number of languages but not in Arabic. In addition there are few studies of the effects of psycholinguistic and morpho-syntactic variables on Arabic lexical retrieval. The current study identified a set of culturally and linguistically appropriate concept labels, and corresponding photographic representations for Levantine Arabic. The set included masculine and feminine nouns, nouns from both types of plural formation (sound and broken), and both rational and irrational nouns. Levantine Arabic speakers provided norms for visual complexity, imageability, age of acquisition, naming latency and name agreement. This delivered a normative database for a set of 186 Arabic nouns. The effects of the morpho-syntactic and the psycholinguistic variables on lexical retrieval were explored using the database. Imageability and age of acquisition were the only significant determinants of successful lexical retrieval in Arabic. None of the other variables, including all the linguistic variables, had any effect on production time. The normative database is available for the use of clinicians and researchers in the Arab world in the domains of speech and language pathology, neurolinguistics and psycholinguistics. The database and the photographic representations will be soon available for free download from the first author’s personal webpage or via email.