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Aphasiology 2022 5;36(5):618-647. Epub 2021 Apr 5.

Department of Neurology, Johns Hopkins University School of Medicine, Phipps 446, 600 N. Wolfe Street, Baltimore, MD 21287.

Background: A clinical diagnosis of primary progressive aphasia relies on behavioral characteristics and patterns of atrophy to determine a variant: logopenic; nonfluent/agrammatic; or semantic. The dual stream model (Hickok & Poeppel, 2000; 2004; 2007; 2015) is a contemporary paradigm that has been applied widely to understand brain-behavior relationships; however, applications to neurodegenerative diseases like primary progressive aphasia are limited.

Aims: The primary aim of this study is to determine if the dual stream model can be applied to a neurodegenerative disease, such as primary progressive aphasia, using both behavioral and neuroimaging data. Read More

Aphasiology 2022 25;36(2):170-197. Epub 2021 Jan 25.

Department of Speech and Hearing Sciences, University of Washington.

Background: Stimulus selection is important to anomia treatment because similarity between trained and untrained words in the mental lexicon may influence treatment generalization. We focused on phonological similarity between trained and untrained words from a clinical trial of Phonomotor Treatment (PMT) that showed gains in confrontation naming accuracy of untrained words post-treatment. One way to capture the amount of similarity between the trained and untrained words is to consider the phonological network path distance between words. Read More

Aphasiology 2021 16;35(12):1-12. Epub 2021 Mar 16.

Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287.

Background: Progressive neurodegenerative impairment with central language features, primary progressive aphasia (PPA), can be further distinguished for many individuals into one of three variants: semantic, non-fluent/agrammatic, and logopenic variant PPA. Variants differ in their relative preservation and deficits of language skills, particularly in word finding and grammar. The majority of elicited language assessments used in this population focus on single noun and verb production, while modifiers and inflectional morphemes are far less commonly examined. Read More

Aphasiology 2021 22;35(4):518-538. Epub 2019 Nov 22.

Department of Neurology, Georgetown University Medical Center, and MedStar National Rehabilitation Hospital, Washington, DC, USA.

Purpose: There is persistent uncertainty about whether sound error consistency is a valid criterion for differentiating between apraxia of speech (AOS) and aphasia with phonemic paraphasia. The purpose of this study was to determine whether speakers with a profile of aphasia and AOS differ in error consistency from speakers with aphasia who do not have AOS. By accounting for differences in overall severity and using a sample size well over three times that of the largest study on the topic to date, our ambition was to resolve the existing controversy. Read More

Aphasiology 2021 22;35(10):1318-1333. Epub 2020 Jul 22.

College of Health Solutions, Arizona State University, Tempe, AZ USA.

Background: Attention deficits frequently accompany language impairments in aphasia. Most research on attention in aphasia focuses on selective attention measured by executive control tasks such as the color-word Stroop or Erickson flanker. This is despite ample evidence in neurotypical adults indicating the existence of multiple, distinct attention subtypes. Read More

Aphasiology 2021 7;35(4):560-591. Epub 2020 Jul 7.

Departments of Neurology, Mayo Clinic, Rochester, MN, USA.

Background: Apraxia of speech (AOS) can be caused by neurodegenerative disease and sometimes is its presenting sign (i.e., primary progressive apraxia of speech, PPAOS). Read More

Aphasiology 2021 18;35(4):424-441. Epub 2020 May 18.

Department of Speech, Language, & Hearing Sciences, Boston University, Boston, MA.

Background: The Directions Into Velocities of Articulators (DIVA) model and its partner, the Gradient Order DIVA (GODIVA) model, provide neurobiologically grounded, computational accounts of speech motor control and motor sequencing, with applications for the study and treatment of neurological motor speech disorders.

Aims: In this review, we provide an overview of the DIVA and GODIVA models and how they explain the interface between phonological and motor planning systems to build on previous models and provide a mechanistic accounting of apraxia of speech (AOS), a disorder of speech motor programming.

Main Contribution: Combined, the DIVA and GODIVA models account for both the segmental and suprasegmental features that define AOS via damage to (i) a speech sound map, hypothesized to reside in left ventral premotor cortex, (ii) a phonological content buffer hypothesized to reside in left posterior inferior frontal sulcus, and/or (iii) the axonal projections between these regions. Read More

Aphasiology 2021 11;35(3):334-356. Epub 2020 Jan 11.

Temple University.

Background: Verbal short-term memory (STM) and the related ability, working memory (WM), are widely understood to be integral components of language production and comprehension. However, assessment of these abilities in people with aphasia is hampered by a lack of valid, standardized measures that are clinically appropriate. Focusing primarily on verbal STM, we held a series of five focus groups with speech-language pathologists (SLPs) to understand better their current clinical practices and their beliefs and attitudes regarding assessment of verbal STM in aphasia. Read More

Aphasiology 2021 19;35(2):186-199. Epub 2019 Dec 19.

Department of Speech Pathology and Audiology, University of South Alabama.

Background: Visual functioning is often affected in persons with aphasia following stroke and other brain injuries. Characterizing the visual functioning of persons with aphasia is imperative in both clinical and research domains; however, visual functioning of persons with aphasia is infrequently assessed or described in either domain.

Aims: This study aims to examine the utility of various visual screening measures as indicated by Hallowell (2008) and document the results of the screening tools for a cohort of persons with aphasia. Read More

Aphasiology 2021 30;35(2):200-221. Epub 2020 Jun 30.

Department of Speech Pathology and Audiology, Miami University, Oxford, United States.

Background: Many people with aphasia have a strong desire to participate in reading activities despite persistent reading challenges. Digital reading devices and text-to-speech (TTS) technology are increasing in popularity and have the potential to help people with aphasia. Systematic investigation of modifiable TTS features provides a means of exploring this potential. Read More

Aphasiology 2021 4;35(3):357-371. Epub 2019 Dec 4.

Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287.

Background: Characterizing productive language deficits following lesions to the right (RH) or left hemispheres (LH) is valuable in identifying appropriate therapeutic goals. While damage to the LH classically is associated with deficits in language, RH lesions also result in changed communication beyond prosody due to cognitive-linguistic effects. Cohesion, reference to introduced content across sentences within discourse, relies on a listener's clear and unambiguous understanding that a reference has occurred. Read More

Aphasiology 2021 21;35(7):984-994. Epub 2020 Apr 21.

University of Arizona.

Aphasiology 2020 23;34(12):1456-1470. Epub 2019 Sep 23.

Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287.

Background: Individuals with primary progressive aphasia (PPA) develop visuospatial deficits over time, and those with logopenic variant (lvPPA) are at greatest risk of developing such deficits. However, not all previous studies of visuospatial deficits in PPA have ensured equivalent duration of disease across variants and few have measured deficits longitudinally.

Aims: The aims of our study were to: 1) investigate differences in baseline visuomotor figure construction, visual figure delayed recall, and figure recognition in PPA variants with similar symptom duration at baseline, and 2) explore patterns of decline in these areas. Read More

Aphasiology 2020 13;34(10):1223-1240. Epub 2019 Sep 13.

Aphasia Research Laboratory, Department of Speech, Language, and Hearing Sciences, Boston University, Boston, MA 02215, USA.

Background: Bilingual persons with aphasia (BWA) may present different degrees and patterns of impairment in their two languages. Previous research suggests that prestroke proficiency may be amongst the factors determining poststroke language impairment in BWA, however this relationship is not well understood.

Aims: The purpose of this study was to examine the relationship between prestroke proficiency and poststroke lexical-semantic performance in BWA and to identify common patterns of language impairment in this population. Read More

Aphasiology 2020 22;34(2):235-253. Epub 2019 Mar 22.

Department of Communication Sciences and Disorders, Temple University.

Background: Perceptual span refers to the field of effective vision during reading comprehension. It is determined by many factors, including reading proficiency. No studies have investigated the perceptual span in people with reading comprehension impairments due to aphasia. Read More

Aphasiology 2020 4;34(7):865-885. Epub 2019 Sep 4.

Memory and Aging Center, Department of Neurology, University of California San Francisco, San Francisco, CA 94158, USA.

Background: Semantic variant primary progressive aphasia (svPPA), a clinical syndrome characterized by loss of semantic knowledge, is associated with neurodegeneration that starts in the anterior temporal lobe (ATL) and gradually spreads towards posterior temporal and medial frontal areas. At the earliest stages, atrophy may be predominantly lateralized to either the left or right ATL, leading to different clinical profiles with greatest impairment of word comprehension or visual/social semantics, respectively.

Methods & Procedures: We report the in-depth longitudinal investigation of cognitive and neuroanatomical features of JB, an unusual case of ATL neurodegeneration with relative sparing of left lateral ATL regions. Read More

Aphasiology 2020 17;34(4):391-410. Epub 2019 Sep 17.

Department of Speech, Language, and Hearing Sciences, Purdue University.

Purpose: Healthy speakers use both word-level and structure-level information to ease sentence production processes. Structural priming facilitates message-structure mapping in aphasia. However, it remains unclear if and how word-level information affects off-line and on-line sentence production in persons with aphasia (PWA). Read More

Aphasiology 2020 31;34(8):943-969. Epub 2019 May 31.

Johns Hopkins University, USA.

Background: In the recent years there has been increasing interest in the effects of attentional control on syntactic comprehension, as measured in garden path sentence resolution. Persons with aphasia (PWA) experience greater penalties in garden path sentences compared to language-unimpaired adults but the origin of this deficit remains a controversial issue. One of the possible deficits has been claimed to be disambiguation of lexical cues in the sentence. Read More

Aphasiology 2020 26;34(2):214-234. Epub 2019 Jul 26.

University of Florida.

Background: Global coherence rating scales have been used by a number of researchers to examine spoken discourse in populations with and without acquired neurogenic communication disorders. The 4-point global coherence (GC) scale in the current study has demonstrated reliability and convergent validity. However, we have not yet established how a global coherence rating corresponds to functional communication. Read More

Aphasiology 2020 6;34(1):119-136. Epub 2019 Jan 6.

University of New Mexico, MSC 01 1195, Albuquerque, NM 87131, (470) 281-0470.

Background: Proposition analysis of the discourse of persons with aphasia has a long history, yielding important advancements in our understanding of communication impairments in this population. Recently, discourse measures have been considered primary outcome measures, and multiple calls have been made for improved psychometric properties of discourse measures.

Aims: To advance the use of discourse analysis in persons with aphasia by providing Main Concept Analysis checklists and descriptive statistics for healthy control performance on the analysis for the Cat in the Tree and Refused Umbrella narrative tasks utilized in the AphasiaBank database protocol. Read More

Aphasiology 2021 1;35(8):1067-1083. Epub 2020 Jun 1.

School of Medical and Health Sciences, Edith Cowan University, Perth, Australia.

: The impact of stroke and aphasia has been recognised as a family problem for many years with studies highlighting spouses' need for information at different times along the recovery journey, for practical and emotional support, recognition, and respite. In particular, the decision-making around discharge from hospital, or planning for rehabilitation, is not always collaborative even though family involvement assists family members to plan and adjust to their new caring role. : This study aims to explore how the wife of a man with aphasia managed his discharge from hospital in the acute phase post-stroke. Read More

Aphasiology 2020 23;34(3):365-375. Epub 2019 Mar 23.

Department of Neurology, Johns Hopkins University School of Medicine.

Background: The rate of decline in language in Primary Progressive Aphasia (PPA) is highly variable and difficult to predict at baseline. The severity of diffuse white matter disease (leukoaraiosis), a marker of overall brain health, may substantially influence the rate of decline.

Aims: To test the hypothesis that leukoaraiosis is associated with a steeper decline in naming in PPA. Read More

Aphasiology 2020 14;34(11):1341-1362. Epub 2020 May 14.

Aphasia Research Laboratory, Department of Speech, Language, and Hearing Sciences, Boston University, Boston, MA, 02215, USA.

Background: Lexical access in bilinguals can be influenced by the demands that different interactional contexts pose on cognitive control processes (Green & Abutalebi, 2013: Adaptive Control Hypothesis; Green, 1998: Inhibitory Control Model). However, how varying cognitive control demands impact lexical access in bilingual persons with aphasia (BPWA) remains unclear. Verbal fluency tasks may provide valuable insights into the interplay between cognitive control and lexical access in BPWA by addressing word generation abilities in language contexts that exert varying degrees of cognitive control effort. Read More

Aphasiology 2020 23;35(4):592-613. Epub 2020 Oct 23.

Temple University, Philadelphia, PA.

Background: The speculation that apraxia of speech (AOS) is not a unitary diagnosis, but consists of different subtypes instead, has been around for decades. However, attempts to empirically substantiate such a notion remain few and far between.

Aims: The primary objective of this article is to consider the different bases for identifying subtypes of AOS, review existing evidence regarding subtypes under each classification basis, and provide discussion and implications for future research. Read More

Aphasiology 2020 3;34(6):664-674. Epub 2020 Mar 3.

Center for Aphasia Research and Rehabilitation, Georgetown University Medical Center.

Background: Findings from several studies have indicated that participants with nfvPPA and participants with svPPA exhibit different patterns on action and object naming tasks, while other recent studies have found that neither participants with nfvPPA nor participants with svPPA show a significant difference in accuracy between object naming and action naming.

Aims: The goal of this study was to test the hypothesis that relative action naming impairment is associated with grammatical ability in PPA, rather than a specific subtype of PPA.

Methods & Procedures: Thirty-four participants with PPA completed the Boston Naming Test, the Action Naming subtest of the Boston Diagnostic Aphasia Examination, and the Northwestern Anagram Test, which was used to measure grammatical ability. Read More

Aphasiology 2019 1;33(7):780-802. Epub 2019 Mar 1.

University of Edinburgh, Edinburgh, Scotland.

Purpose: Impaired message-structure mapping results in deficits in both sentence production and comprehension in aphasia. Structural priming has been shown to facilitate syntactic production for persons with aphasia (PWA). However, it remains unknown if structural priming is also effective in sentence comprehension. Read More

Aphasiology 2019 16;33(11):1410-1417. Epub 2018 Nov 16.

Department of Neurology, Mayo Clinic, Rochester, MN.

Background: Past research has demonstrated that electroencephalography (EEG) is sensitive to what we now know as Primary Progressive Aphasia (PPA); however, the EEG profiles of patients with Primary Progressive Apraxia of Speech (PPAOS) and PPA, in the context of current consensus criteria, have not been studied.

Aims: The primary goal of this study was to explore the EEG profiles of patients of the nonfluent/ agrammatic variant of PPA (agPPA) and PPAOS.

Methods And Procedures: Three patients with agPPA and five patients with PPAOS (two with aphasia) completed a head MRI scan and clinical EEG recording. Read More

Aphasiology 2019 16;33(9):1137-1153. Epub 2018 Nov 16.

Department of Speech-Language-Hearing Sciences, Graduate Center, City University of New York, NY, USA.

Background: Language mixing in bilingual speakers with aphasia has been reported in a number of research studies, but the reasons for the mixing and whether it reflects typical or atypical behaviour has been a matter of debate.

Aims: In this study we tested the hypothesis that language mixing behaviour in bilingual aphasia reflects lexical retrieval difficulty.

Methods & Procedures: We recruited a Hebrew-English bilingual participant with mild-moderate non-fluent agrammatic aphasia and assessed his languages at three timepoints. Read More

Aphasiology 2019 23;33(6):667-688. Epub 2018 Aug 23.

Department of Psychology, University of Alabama, Birmingham, AL, 35294, USA, ;

Background: Deficits in fluent language production are a hallmark of aphasia and may arise from impairments at different levels in the language system. It has been proposed that difficulty resolving lexical competition contributes to fluency deficits.

Aims: The present study tested this hypothesis in a novel way: by examining whether narrative speech production fluency is associated with difficulty resolving lexical competition in spoken word recognition as measured by sensitivity to phonological neighborhood density. Read More

Aphasiology 2019 23;33(6):689-709. Epub 2018 Jul 23.

VA Pittsburgh Healthcare System and University of Pittsburgh, Pittsburgh, PA.

Background: Item response theory (IRT; Lord & Novick, 1968) is a psychometric framework that can be used to model the likelihood that an individual will respond correctly to an item. Using archival data (Mirman et al., 2010), Fergadiotis, Kellough, and Hula (2015) estimated difficulty parameters for the Philadelphia Naming Test (PNT; Roach, Schwartz, Martin, Grewal, & Brecher, 1996) using the 1-parameter logistic IRT model. Read More