Time reference decoupled from tense in agrammatic and fluent aphasia

Background: Reference to an event’s time frame can be accomplished through verb inflection. In agrammatic aphasia, a deficit in past time reference has been identified by Bastiaanse and colleagues (2011). In fluent aphasia, specific problems with this time frame (expressed by the past tense) have been found as well (Dragoy & Bastiaanse, 2013; Jonkers & de Bruin, 2009). However, time reference does not always coincide with tense; in languages such as Dutch and English, reference to the past can be established by using past tense (e.g., “he wrote a letter”) or a present tense auxiliary in combination with a participle, i.e., the present perfect (e.g., “he has written a letter”).

Aims: The goal of this study is twofold. First, it aims to untangle tense problems from problems with past time reference through verb morphology in people with aphasia. Second, this study aims to compare the production of time reference inflection by people with agrammatic and fluent aphasia.

Methods & Procedures: A sentence completion task was used to elicit reference to the non-past and past in Dutch. Reference to the past was tested through (1) a simple verb in past tense and (2) a verb complex with an auxiliary in present tense + participle (the present perfect). Reference to the non-past was tested through a simple verb in present tense. Fourteen agrammatic aphasic speakers, sixteen fluent aphasic speakers, and twenty non-brain-damaged speakers (NBDs) took part in this study. Data were analysed quantitatively and qualitatively.

Outcomes & Results: NBDs scored at ceiling and significantly higher than the aphasic participants. Agrammatic speakers performed worse than fluent speakers, but the pattern of performance in both aphasic groups was similar. Reference to the past through past tense and [present tense auxiliary + participle] was more impaired than reference to the non-past. An error analysis revealed differences between the two groups.

Conclusions: People with agrammatic and fluent aphasia experience problems with expressing reference to the past through verb inflection. This past time reference deficit is irrespective of the tense employed. The error patterns between the two groups reveal different underlying problems.     

Listener perceptions of simulated fluent speech in nonfluent aphasia

Background: People with aphasia (PWA) are frequently perceived less favourably by listeners than their peers. These perceptions include incorrect assumptions that can prevent successful social interactions. While communication partner training has been shown to improve social outcomes related to the listener, changing the verbal output of PWA may also yield more favourable listener perceptions about the speech, speaker, and their own affective response. We investigated the effects of artificially altered fluency (i.e., simulated fluency) on listeners’ subjective impressions.

Aims: The purpose of the study was to (1) confirm that listeners perceive PWA less favourably than their neurologically healthy peers and (2) determine the effects of simulated fluency on listener perceptions about PWA.

Methods & Procedures: Thirty-eight listeners heard nine narrative monologue language samples from three conditions (i.e., speakers with nonfluent aphasia, simulated fluent samples from the same speakers, and neurologically healthy speakers). Listeners responded to a nine-item questionnaire that probed perceptions about speech output, speaker attributes, and listener feelings.

Outcomes & Results: Listeners perceived PWA less favourably than their neurologically healthy peers. Simulated fluency yielded more positive listener perceptions for all questionnaire items except speech intelligibility, which was unchanged by simulated fluency.

Conclusions: Simulated fluency improved listener perceptions of PWA significantly, indicating that speech fluency may be a socially valid treatment target in aphasia. Beyond direct training of communication partners, changing the verbal output of aphasic speech can also yield more positive listener perceptions of PWA.     

Investigation of self-monitoring in fluent aphasia with jargon

Background: Some individuals with fluent aphasia produce jargon errors in speech production. Jargon likely results from derailed encoding operations required for language production, although the exact mechanism remains debated. It is also unclear if persons who produce jargon are able to self-monitor; that is, detect the non-word status of their imminent utterance and self-correct the error.

Aims: This study investigated the characteristics of speech monitoring in individuals with fluent aphasia who produce jargon. The association of speech monitoring with amount of jargon produced and success in auditory comprehension was examined. Further, the role of post-articulatory auditory feedback on speech-monitoring success was examined by introducing an auditory masker (white noise). Finally, the influence of task demands on amount of jargon and speech monitoring was examined.

Methods & Procedures: Five individuals with fluent aphasia with jargon participated in the study. Speech monitoring was tested using three production tasks (picture naming, non-word repetition, and word repetition) under two listening conditions (normal listening and masking noise). Speech-monitoring score was derived from self-judgements of production accuracy. Auditory processing was examined in speech discrimination, lexical decision, and single-word identification tasks.

Outcomes & Results: Results indicated that severity of self-monitoring impairment is: (1) strongly correlated with severity of jargon production, (2) poorly correlated with auditory processing abilities, (3) worse under masking noise, and (4) worse for naming compared to repetition.

Conclusions: Overall, all five participants with jargon demonstrated severely impaired speech monitoring under both listening conditions across all three production tasks, suggesting that the role of speech-monitoring impairment in jargon cannot be disregarded. The increase in amount of jargon and severity of speech-monitoring failure with increased linguistic demands of the production task (as in picture naming and non-word repetition) raises the possibility of a post-semantic deficit in accessing phonological codes. This possible locus of deficit, and implications for understanding production of jargon, are discussed.     

Primary progressive aphasia: a comparative study of progressive nonfluent aphasia and semantic dementia

Primary progressive aphasia (PPA), a degenerative disorder, is often misdiagnosed as Alzheimer's disease. Its subtypes, semantic dementia (SD), and progressive nonfluent aphasia (PNFA), are often difficult to differentiate from each other. Our objective was to highlight the differences in the language profiles of patients with SD and PNFA. To bring out these differences, we report two patients with PPA, one with SD and the other with PNFA. They were administered the Western aphasia battery (WAB) and a semantic battery, which assesses semantic memory. The profiles of language impairment on the WAB indicated that the patient with PNFA had syntactic errors in expressive speech but relatively preserved semantics and comprehension, whereas the patient with SD had preserved syntax but made semantic errors in expressive speech, and had impaired comprehension. There were differences in their performance on the semantic battery too. The patient with SD made relatively less errors on confrontation naming, although on the pointing task he failed to point to those line drawings, which he was unable to name on confrontation. In contrast, the finding of the PNFA patient was the reverse of this. Supplementing conventional neuropsychological tests with formal tests for assessment of language functions is useful in the early diagnosis of PPA. The performance of PPA patients on a detailed assessment of language that includes use of formal tests such as the semantic battery helps to differentiate PNFA from SD.     

Emergence of artistic talent in progressive nonfluent aphasia: a case report

Some patients with frontotemporal lobar degeneration have developed artistic skills after the onset mainly in painting and music. Most of these cases have semantic dementia (SD), one of the frontotemporal lobar degeneration subtypes. In previously reported cases, the paintings made by patients with SD were usually hyper realistic, without a significant symbolic or abstract component. Here, we report on a patient with progressive nonfluent aphasia (PNFA), another frontotemporal lobar degeneration subtype, who started making creative bamboo crafts after PNFA onset. His techniques were completely his original; he devised the shapes of the crafts and made them without samples. His work did not become an obsessive preoccupation. The artistic style expressed by patients with PNFA differs from that expressed by patients with SD. Therefore, the underlying mechanisms for the emergence of artistic talent might differ between SD and PNFA.     

Use of co-verbal gestures during word-finding difficulty among Cantonese speakers with fluent aphasia and unimpaired controls

Background: Co-verbal gestures refer to hand or arm movements made during speaking. Spoken language and gestures have been shown to be tightly integrated in human communication.

Aims: The present study investigated whether co-verbal gesture use was associated with lexical retrieval in connected speech in unimpaired speakers and persons with aphasia (PWA).

Methods & Procedures: Narrative samples of 58 fluent PWA and 58 control speakers were extracted from Cantonese AphasiaBank. Based on the indicators of word-finding difficulty (WFD) in connected speech adapted from previous research and a gesture annotation system with independent coding of gesture forms and functions, all WFD instances were identified. The presence and type of gestures accompanying each incident of WFD were then annotated. Finally, whether the use of gesture was accompanied by resolution of WFD (i.e., the corresponding target word could be retrieved) was examined.

Outcomes & Results: Employment of co-verbal gesture did not seem to be related to the success of word retrieval. PWA’s naming ability at single-word level and their overall language ability (as reflected by the aphasia quotient of the Cantonese version of the Western Aphasia Battery) were found to be the two strongest predictors of success rate of resolving WFD.

Conclusions: The Lexical Retrieval Hypothesis highlighting the facilitative functions of iconic and metaphoric gestures in lexical retrieval was not supported. Challenges in conducting research related to WFD, and the clinical implications in gesture-based language intervention for PWA were discussed.     

Dynamic aphasia in progressive supranuclear palsy: a deficit in generating a fluent sequence of novel thought

We report a patient (KAS) who presented with pure dynamic aphasia in the context of progressive supranuclear palsy (PSP). KAS had the hallmark propositional language impairment in the context of preserved naming, reading, repetition and comprehension skills. The severity of KAS's propositional language deficit was demonstrated to be comparable to other dynamic aphasic patients. Remarkably, despite virtually abolished propositional speech, KAS was unimpaired on word and sentence level generation tasks that required a single response. This dissociation was further investigated on two discourse level generation tasks that required the generation of multiple connected sentences. Quantitative production analysis and novelty measures demonstrated that her performance was extremely reduced and characterised by a lack of novel words and sentences and a tendency to perseverate. This pattern of performance suggests that there may be two subtypes of dynamic aphasia. Patients with the more documented first subtype have language-specific deficits, fail word and sentence level generation tests and have left inferior frontal gyrus lesions. Patients with the second subtype, like KAS, pass word and sentence level generation tests and fail discourse level generation tests. They have a verbal and non-verbal generation deficit and bilateral frontal and subcortical damage. Our findings are discussed with reference to executive functioning accounts of dynamic aphasia and models of speech production. We interpret our patients' impairment as being underpinned by a deficit in one set of mechanisms involved in discourse generation; namely the generation of a fluent sequence of novel thought.     

Verbs and time reference in Standard Indonesian agrammatic speech

Background: It has been shown for a number of languages that verb retrieval and verb inflection are impaired in agrammatic speech. Several studies showed that, while some agrammatic speakers are relatively good in verb retrieval but poor in verb inflection, others show the inverse pattern (Dutch: Bastiaanse & Jonkers, 1998 Bastiaanse, R. and Jonkers, R. 1998. Verb retrieval in action naming and spontaneous speech in agrammatic and anomic aphasia. Aphasiology, 12: 951–969. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]; Italian: Rossi & Bastiaanse, 2008 Rossi, E. and Bastiaanse, R. 2008. Spontaneous speech in Italian agrammatic aphasia. A focus on verb production. Aphasiology, 22: 347–362. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar], among others). However, not all languages use verb inflection to express sentence internal and external relationships, such as agreement, tense, and aspect; some use free-standing grammatical morphemes instead. Standard Indonesian (SI) is such a language.

Aims: The aim of the current study is to find out whether the production of free-standing grammatical morphemes—which specify time frame and are thus comparable to tense and aspect inflection in other languages—is impaired in SI agrammatic spontaneous speech, and whether there is a similar inverse relationship between verb retrieval and the use of these morphemes, as suggested by findings on verb inflection in other languages.

Methods & Procedures: A total of 21 adult speakers of SI (6 with Broca's aphasia with mild to moderate agrammatic speech and 15 without history of neurological problems) participated in the study. From the speech of each participant 300 words were extracted, and the occurrence of verbal predicates, aspectual adverbs, and lexical adverbs of time was counted. Type-token ratios (TTR) were used to express the diversity of lexical verbs produced, and the proportion of aspectual and temporal lexical adverbs per verbal predicate was calculated for all participants.

Outcomes & Results: An inverse relationship was observed between the verb variability and the proportion of aspectual adverbs. The agrammatic participants who used a low proportion of aspectual adverbs did not compensate with over-production of lexical adverbs.

Conclusions: Based on the results of the current study we propose that the inverse relationship between lexical diversity of the verbs and the use of aspectual adverbs reflects the same underlying deficit as the inverse relationship between lexical diversity of verbs and verb inflection observed in Dutch and Italian. Apparently it is difficult for agrammatic speakers to simultaneously retrieve verbs (names of the events) and specify the time frame in which the events take place. This has some important clinical implications.     

Concurrent validity of Zimbardo Time Perspective Inventory profiles: A secondary analysis of data from the United Kingdom

This paper examined the association between membership in profiles based on a shortened form of the Zimbardo Time Perspective Inventory (ZTPI-S; McKay, Andretta, McGee, & Worrell, 2014) and other temporal and psychosocial variables. Participants consisted of 1620 adolescents attending high school in Northern Ireland. ZTPI-S scores had correlations with other temporal and psychosocial variables that were similar to those reported for ZTPI scores in previous studies. Four ZTPI-S profiles were identified—Balanced, Past Negative, Present Hedonistic, and Future—and results indicated that these profiles had theoretically meaningful relationships with self-esteem, self-efficacy, aggression, parental attachment, consideration of future consequences, and future temporal focus. Unlike studies of college students where the Balanced profile was related to more adaptive functioning, the Future profile was related to more adaptive functioning. Future studies are needed to establish the generalizability of these profiles and to determine if there are developmental differences in which profiles are more adaptive.     

Lexicality effects in word and nonword recall of semantic dementia and progressive nonfluent aphasia

Background: Verbal working memory is an essential component of many language functions, including sentence comprehension and word learning. As such, working memory has emerged as a domain of intense research interest both in aphasiology and in the broader field of cognitive neuroscience. The integrity of verbal working memory encoding relies on a fluid interaction between semantic and phonological processes. That is, we encode verbal detail using many cues related to both the sound and meaning of words. Lesion models can provide an effective means of parsing the contributions of phonological or semantic impairment to recall performance.

Methods & Procedures: We employed the lesion model approach here by contrasting the nature of lexicality errors incurred during recall of word and nonword sequences by three individuals with progressive nonfluent aphasia (a phonological dominant impairment) compared to that of two individuals with semantic dementia (a semantic dominant impairment). We focused on psycholinguistic attributes of correctly recalled stimuli relative to those that elicited a lexicality error (i.e., nonword → word OR word → nonword).

Outcomes & Results: Patients with semantic dementia showed greater sensitivity to phonological attributes (e.g., phoneme length, wordlikeness) of the target items relative to semantic attributes (e.g., familiarity). Patients with PNFA showed the opposite pattern, marked by sensitivity to word frequency, age of acquisition, familiarity, and imageability.

Conclusions: We interpret these results in favour of a processing strategy such that in the context of a focal phonological impairment patients revert to an over-reliance on preserved semantic processing abilities. In contrast, a focal semantic impairment forces both reliance on and hypersensitivity to phonological attributes of target words. We relate this interpretation to previous hypotheses about the nature of verbal short-term memory in progressive aphasia.     

Treatment of word-finding deficits in fluent aphasia through the manipulation of spatial attention: Preliminary findings

BACKGROUND: Attention, the processing of one source of information to the exclusion of others, is important for most cognitive processes, including language. Evidence suggests not only that dysfunctional attention mechanisms contribute to language deficits after stroke, but also that orienting attention to a patient's ipsilesional hemispace recruits attention mechanisms in the intact hemisphere and improves language functions in some persons with aphasia. AIMS: The aim of the current research was to offer proof of concept for the strategy of improving picture-naming performance in fluent aphasia by moving stimuli into the left hemispace. It was hypothesised that repeated orientation of attention to the ipsilesional hemispace during picture naming would lead to improved naming accuracy for participants with fluent aphasia. METHODS #ENTITYSTARTX00026; PROCEDURES: Three participants with stable fluent aphasia received daily treatment sessions that consisted of naming simple line drawings presented 45 degrees to the left of body midline on a computer monitor. Naming probes were administered before initiation of the treatment protocol to establish a baseline, and before each treatment session to measure change during treatment. The C statistic was used to establish the stability of baseline performance and to determine whether the slope of the treatment phases differed significantly from the slope of the baseline. OUTCOMES #ENTITYSTARTX00026; RESULTS: Two of the three participants showed significant improvement over baseline performance in the percent correct of naming probes. One participant showed no improvement over baseline accuracy. CONCLUSIONS: Results suggest that engaging right-hemisphere attention mechanisms may improve naming accuracy in some people with fluent aphasia. Findings justify further investigation of this treatment in a larger controlled study.     

Voice onset time in aphasia,apraxia of speech and dysarthria: a review

Voice onset time (VOT) is an objective temporal acoustic parameter defined as the time between the release of the oral constriction for plosive production and the onset of vocal fold vibrations. Many researchers consider VOT to be the most reliable acoustic cue for the distinction between voiced and voiceless stops. Previous studies have explored the physiological and linguistic factors underlying VOT production in normal speakers across several languages. A major clinical goal of acoustic analysis in speech disorder is to establish a correlation between the acoustic abnormalities and the phonetic perturbations. VOT could thus be used as an acoustic parameter that indicates the phonetic contrast between voiced and voiceless stops. This paper includes a critical review of the measurement of VOT, factors of VOT variability and the effect of neurogenic communication disorders on VOT. We review the VOT data from subjects who exhibit aphasia, apraxia of speech and dysarthria. These studies reveal that VOT perturbations in aphasia have been interpreted as phonemic or phonetic errors, while VOT abnormalities in apraxia of speech and dysarthria grossly reflect loss of motor control.     

Remembering my friends: Medial prefrontal and hippocampal contributions to the self‐reference effect on face memories in a social context

Memories associated with the self are remembered more accurately than those associated with others. The memory enhancement related to the self is known as the self‐reference effect (SRE). However, little is known regarding the neural mechanisms underlying the SRE in a social context modulated by social relationships. In the present fMRI study, we investigated encoding‐related activation of face memories encoded with the self‐referential process in a social context that was manipulated by imagining a person‐to‐person relationship. Healthy young adults participated in the present study. During encoding, participants encoded unfamiliar target faces by imagining a future friendship with themselves (Self), their friends (Friend), or strangers (Other). During retrieval, participants were presented with target and distracter faces one by one, and they judged whether each face had been previously learned. In the behavioral results, target faces encoded in the Self condition were remembered more accurately than those encoded in the Other condition. fMRI results demonstrated that encoding‐related activation in the medial prefrontal cortex (mPFC) was significantly greater in the Self condition than in the Friend or Other conditions. In addition, the generalized psycho‐physiological interaction (gPPI) analysis showed that functional connectivity between activation in the hippocampus and the cortical midline structures (CMSs), including the mPFC and precuneus, was significant in the Self but not in the Other condition. These findings suggest that the SRE in a social context could be involved in the interaction between the CMS regions, which are related to the self‐referential process, and the hippocampus related to the memory process. Hum Brain Mapp 38:4256–4269, 2017. © 2017 Wiley Periodicals, Inc.     

Significance of speech production errors on cross-linguistic processing in Sepedi-English individuals with bilingual aphasia: a case series analysis

Background: Bilingual aphasia forms a significant part of speech-language pathologists’ (SLP) caseload, globally, and specifically in South Africa. Few tools supporting clinical decision-making are available due to limited understanding of typical and disordered cross-linguistic processing (how the languages interact). Speech errors may provide insight about “hidden” bilingual mechanisms.

Objectives: To determine what speech errors can impart about cross-linguistic processing, as well as, associated language and impairment variables in Sepedi-English individuals with aphasia.

Method: The case series included six participants, purposively selected from three rehabilitation sites in South Africa. Detailed language and clinical profiles were obtained. Participants performed a confrontation naming task in their most dominant (MDL) and less dominant language (LDL). Responses were audio recorded, transcribed, and analyzed for overall accuracy and error type in MDL and LDL; verified by a Sepedi-speaking linguist and a qualified SLP.

Results: (1) No statistically significant differences in MDL-LDL naming accuracy were found, supporting recent literature of simultaneous inter-activation of both languages and shared word retrieval mechanisms. All types of speech errors occurred, and semantic errors were produced most frequently and consistently in each participant’s MDL and LDL. (2) Language proficiency, language recovery patterns, and aphasia type (Broca’s and Anomic) and severity (mild and/or moderate) appeared to be more strongly linked to cross-linguistic processing than Sepedi-English linguistic differences and age of acquisition of both languages.

Conclusions: Participants with bilingual aphasia may use typical cross-linguistic and word retrieval mechanisms, concurring with current theories of bilingualism. Findings are preliminary, warranting investigations of other language tasks, modalities, pairs, and related variables.     

Treatment of naming in nonfluent aphasia through manipulation of intention and attention: a phase 1 comparison of two novel treatments.

Twenty-three chronic nonfluent aphasia patients with moderate or severe word-finding impairments and 11 with profound word-finding impairments received two novel picture-naming treatments. The intention treatment initiated picture-naming trials with a complex left-hand movement and was designed to enhance right frontal participation during word retrieval. The attention treatment required patients to view visual stimuli for picture-naming trials in their left hemispace and was designed to enhance right posterior perisylvian participation during word retrieval. Because the intention treatment addressed action mechanisms and nonfluent aphasia reflects difficulty initiating or maintaining action (i.e., language output), it was hypothesized that intention component of the treatment would enhance re-acquisition of picture naming more than the attention component. Patients with moderate and severe word-finding impairment showed gains with both treatments but greater incremental improvement from one treatment phase to the next with the intention than the attention treatment. Thus, the hypothesis that intention component would be a more active constituent than the attention component was confirmed for these patients. Patients with profound word-finding impairment showed some improvement with both treatments but no differential effects for the intention treatment. Almost all patients who showed treatment gains on either treatment also demonstrated generalization from trained to untrained items.