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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 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 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 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 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

Aphasiology 2019 1;33(4):382-404. Epub 2017 Dec 1.

Department of Neurology, University of Iowa Carver College of Medicine, 2155 RCP, Iowa City, Iowa, USA.

Background: Previous work has investigated extensively the neuroanatomical correlates of lexical retrieval for words for concrete entities. Musical entities, such as musical instruments, are often included in studies of category-specific naming deficits, but have rarely been the focus of such work.

Aims: This article reviews a program of research investigating the neuroanatomical basis for lexical retrieval of words for unique (i. Read More

Aphasiology 2019 4;33(2):125-139. Epub 2018 Sep 4.

VA Puget Sound Health Care System, Seattle, and University of Washington, Seattle.

Background: Aphasia is an acquired language disorder that makes it difficult for people to produce and comprehend language, with every person with aphasia (PWA) demonstrating difficulty accessing and selecting words (anomia). While aphasia treatments typically focus on a single aspect of language, such as word retrieval, the ultimate goal of aphasia therapy is to improve communication, which is best seen at the level of discourse.

Aims: This retrospective study investigated the effects of one effective anomia therapy, Phonomotor Treatment, on discourse production. Read More

Aphasiology 2019 16;33(2):216-233. Epub 2018 Apr 16.

Division of Speech and Hearing Sciences, University of Hong Kong, Hong Kong.

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). Read More

Aphasiology 2018 28;32(9):1010-1030. Epub 2018 Jun 28.

Department of Neurology, Johns Hopkins University School of Medicine, Phipps 446, 600 N. Wolfe Street, Baltimore, Maryland 21287 USA; Telephone (410) 614-2381;

Background: Individuals with primary progressive aphasia (PPA) and their caregivers want to know what to expect so that they can plan support appropriately. The ability to predict decline in naming and semantic knowledge, and advise individuals with PPA and their caregivers regarding future planning, would be invaluable clinically.

Aims: The aims of this study were to investigate patterns of decline in naming and semantic knowledge in each of the clinical variants of PPA (logopenic variant PPA, lvPPA; nonfluent agrammatic PPA, nfaPPA; and semantic variant PPA, svPPA) and to examine the effects of other variables on rate of decline. Read More

Aphasiology 2019 21;33(1):1-30. Epub 2018 Mar 21.

Department of Cognitive Science, Johns Hopkins University, Baltimore, MD, USA.

Background: Advances in statistical methods and computing power have led to a renewed interest in addressing the statistical analysis challenges posed by Small-N Designs (SND). Linear mixed-effects modeling (LMEM) is a multiple regression technique that is flexible and suitable for SND and can provide standardized effect sizes and measures of statistical significance.

Aims: Our primary goals are to: 1) explain LMEM at the conceptual level, situating it in the context of treatment studies, and 2) provide practical guidance for implementing LMEM in repeated measures SND. Read More

Aphasiology 2018 2;32(8):902-921. Epub 2017 Oct 2.

Dept. of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina.

Background: Apraxia of Speech (AOS) has been associated with deviations in consonantal voice-onset-time (VOT), but studies of vowel acoustics have yielded conflicting results. However, a speech motor planning disorder that is not bound by phonological categories is expected to affect vowel as well as consonant articulations.

Aims: We measured consonant VOTs and vowel formants produced by a large sample of stroke survivors, and assessed to what extent these variables and their dispersion are predictive of AOS presence and severity, based on a scale that uses clinical observations to rate gradient presence of AOS, aphasia, and dysarthria. Read More

Aphasiology 2018 18;32(7):839-854. Epub 2017 Dec 18.

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

Background: Functional neuroimaging techniques can provide a unique window into the neural basis of language recovery after a stroke. The functional neuroimaging literature on post-stroke language recovery is complex; multiple factors such as the time post-stroke, degree of initial impairment, nature of the task, and lesion location and size, influence recovery patterns. Some of these factors may not be applicable across different stroke participants, and therefore, influence recovery trajectories in vastly different manners across patients. Read More

Aphasiology 2018 9;32(6):693-719. Epub 2018 Mar 9.

University of Alabama at Birmingham.

Aims: The purpose of this study is twofold: (1) to examine the feasibility of providing high-tech augmentative and alternative communication (AAC) treatment to people with chronic aphasia, with the goal of evoking changes in spoken language; and (2) to identify evidence of AAC-induced changes in brain activation.

Method & Procedures: We employed a pre- post-treatment design with a control (usual care) group to observe the impact of an AAC treatment on aphasia severity and spoken discourse. Further, we used functional magnetic resonance imaging (fMRI) to examine associated neural reorganization. Read More

Aphasiology 2018 14;32(Suppl 1):45-46. Epub 2018 Aug 14.

Shirley Ryan AbilityLab, Chicago, IL.

Aphasiology 2018 14;32(1 Suppl):115-116. Epub 2018 Aug 14.

Department of Communication Sciences and Disorders St Johns University.

Aphasiology 2018 14;32(Suppl 1):93-95. Epub 2018 Aug 14.

Dept Communication Sciences and Disorders, Temple University, Philadelphia, PA.

Aphasiology 2018 6;32(4):475-478. Epub 2017 Nov 6.

University of Massachusetts Amherst, Department of Communication Disorders.