The Effect of Word Retrieval Therapy in Primary Progressive Aphasia: A Single-Case Study

Abstract

Background: Anomia is a common symptom that can be detrimental to the everyday communication of patients with primary progressive aphasia (PPA). Studies on the anomia treatment in PPA demonstrate that re-learning is possible, but the maintenance and generalization of improvements are limited. The treatment of word retrieval in PPA has typically centered on the retrieval of single lexical items. Little is known about the effects of word-finding treatments in discourse tasks on lexical retrieval. Objectives: The purpose of this study was to introduce a combined semantic/phonological cueing treatment in the context of narrative discourse as a novel method for the treatment of word retrieval difficulty in a PPA patient and compare its effects with the effect of cueing treatment in the context of single words. Methods: One individual with PPA (FK) participated in this single-subject interventional study. FK was a 56-year-old woman with a one-year history of word finding difficulties following Frontotemporal dementia. She received 16 sessions of naming treatment over an eight-week period. The participant completed three baselines prior to treatment. The treatment used a semantic and phonological cueing hierarchy (four weeks, two times a week), followed by a cueing in a story-retelling context (four weeks, two times a week). The main outcome was the naming ability assessment score administered 10 times in order to examine the effectiveness of the therapy through statistical analysis. Results: The participant showed a significant improvement in the word retrieval ability in all stimuli and each set separately related to the therapies phases (P < 0.001). Nevertheless, no significant differences were observed between the therapies (P = 0.26). Following the integrated therapy, FK showed a slightly significant improvement in untreated words. Conclusions: Generally, without considering the type of therapy during this study, in spite of the progressive nature of the disease, word retrieval ability of the patient improved via both treatment programs. Furthermore, the generalization of untreated items and maintenance of treated items also were occurred to some extents. However, there was no evidence of integrated discourse context in cueing hierarchy protocol to make it elaborated and cause a greater effect in people with PPA. As the first known study to trial this issue in the context of PPA, its findings may warrant further investigations.

Language training for oral and written naming impairment in primary progressive aphasia: a review

“…Specifically, all studies have reported significant immediate gains in oral and/or written naming for trained items regardless of the grammatical class treated. However, most studies, except a few [66,77,79,80,83,84], have failed to show larger generalization effects of a particular lexical retrieval treatment technique for untrained items when applied to a specific variant of PPA. Studies that examined this aspect have also reported effects on language tasks such as syntactic generation tasks [76] and discourse measures [79] after lexical retrieval cueing hierarchy treatment in nf/avPPA and svPPA subjects, respectively.…”

“…As already described, naming impairment in PPA may reflect breakdown at one or more stages of the naming process [33][34][35]. In line with these considerations, several studies have investigated the effectiveness of naming treatments, including semantic, lexical-phonological and lexical-orthographic interventions and/or the combination of them, in patients with progressive wordfinding difficulties [21,25,60], but only a few studies have compared the effects of different approaches in the same PPA-subtype patients [65][66][67][68][69][70][71][72][73][74].…”

“…In this case, patients are requested to read a target story in order to be familiar with it and a question with minimal semantic information is asked in order to retrieve the target word. If the patient gives an incorrect answer, semantic and phonological cues and sentence completion cues will be provided [66]. In RRIPP, participants are required to name the picture presented on a computer screen, using the written and/or the spoken form as model before the picture disappear [18,82].…”

“…Specifically, two studies have reported evidence of lexical retrieval treatment only in subjects with a diagnosis of nf/avPPA [66,76], three only in patients with svPPA [65,75,78] and two only in patients with l/ phvPPA [80,81]. The other six studies included participants with different variants of PPA, such as nf/avPPA, svPPA, l/phvPPA and mixed PPA [18,77,79,[82][83][84] and aimed to examine the effects of lexical retrieval treatment on oral and/or written naming abilities by comparing different subtypes of PPA.…”

“…However, in the shortened version in the study of Kim [ 81 ], questions on the autobiographical information in the semantic cue category are included without the semantic plausibility judgment step. The cueing hierarchy treatments have also been used for word retrieval in a discourse context [ 66 , 81 ]. In this case, patients are requested to read a target story in order to be familiar with it and a question with minimal semantic information is asked in order to retrieve the target word.…”