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Duffy, Joseph R

0000-0001-8206-3432

Mayo Clinic

Department of Neurology, Mayo Clinic, Rochester, MN.

Citations 30

Distinct 11C-ER176 PET Neuroinflammatory Profiles and Tau Colocalization in Progressive Apraxia of Speech With and Without Parkinson-plus Syndrome

Clinical Nuclear Medicine | June 30, 2025 | Volume: 50 | Issue: 8 | Pages: 731-742

10.1097/rlu.0000000000005962 | PMID 40587210

Background: Progressive apraxia of speech (PAOS) is a neurodegenerative disorder most commonly arising from a 4-repeat tauopathy that affects the programming or planning of speech, although many patients develop a Parkinson-plus syndrome. The role of neuroinflammation as a disease mechanism is unknown. We investigated the spatial pattern of neuroinflammation in PAOS using PET and evaluated whether it is associated with disease severity, presence of Parkinson-plus features, and tau PET uptake. Patients and Methods: Twenty-five PAOS patients (13 with Parkinson-plus features) and 30 controls underwent inflammatory 11C-ER176 and tau 18F-flortaucipir PET scans as well as detailed clinical assessments. Multiple linear regression analyses compared the inflammatory standardized uptake value ratio (SUVR) between PAOS and controls and assessed the relationship with clinical test scores. Pearson correlation analysis examined the relationship between inflammatory and tau SUVRs. Results: PAOS had greater neuroinflammatory SUVR than controls in the precentral, supplementary motor area, frontal gyri, putamen, pallidum, subthalamic nucleus, and red nucleus (adjusted P < 0.05). Greater neuroinflammation was associated with worse parkinsonism, and patients who had developed Parkinson-plus features showed a broader pattern of neuroinflammation, extending to prefrontal, temporal and parietal cortices. Neuroinflammation correlated with tau uptake in most (96%) PAOS patients (r > 0.3, P < 0.05). The higher correlation was associated with worse parkinsonism (r = 0.61, P < 0.05) and disease severity (r = 0.54, P < 0.05). Conclusions: 11C-ER176 PET analysis demonstrates neuroinflammation in frontal and subcortical regions in PAOS which is particularly severe and widespread with the development of Parkinson-plus clinical features. The colocalization of neuroinflammation and tau may support a relationship between these disease mechanisms.
Testing Feasibility of a Self-Administered Hearing Test for Patients With Progressive Apraxia of Speech and Aphasia

American Journal of Audiology | February 18, 2025 | Volume: 34 | Issue: 1 | Pages: 220-226

10.1044/2024_aja-24-00197 | PMID 39964359

Background and Objectives: Hearing loss is relatively common in older individuals, and individuals with frontotemporal lobar degeneration (FTLD) are no exception; this can exacerbate communication difficulties stemming from speech-language impairments. The co-occurrence of these symptoms can contribute to increased frustration and isolation for patients and their communication partners. The objective of this study was to evaluate the feasibility of self-administered hearing testing. Ultimately, this could be administered remotely, which would increase access to assessment and inform management for this population. Method: Seventeen patients with underlying FTLD, clinically presenting with progressive apraxia of speech with and without agrammatic aphasia, independently completed the Home Hearing Test supervised while in office. Results: Three patients self-reported hearing loss, but results for 100% recommended formal evaluation. Eleven patients demonstrated good test accuracy. Six patients had “poor” or not computable accuracy; among them, five had evidence of cognitive impairment and/or behavioral changes, and one had known severe hearing loss, although differences between those with good and poor test accuracy were not significant. Patients with poor test accuracy had more difficulty with limb praxis. Conclusions: Most participants independently completed the test, though some had reduced test accuracy that may have been associated with cognitive impairment and/or limb apraxia. This study supports the need for hearing screenings in all patients with progressive apraxia of speech and aphasia and highlights both the feasibility and caution required in implementing self-administered testing protocols. Further work should evaluate the feasibility of in-home hearing screenings in a broader range of FTLD phenotypes and directly compare sensitivity and specificity of hearing loss detection with in-clinic administration. Supplemental Material: https://doi.org/10.23641/asha.28306613
Progression of Motor Speech Function in Speakers With Primary Progressive Apraxia of Speech

Journal of Speech, Language, and Hearing Research | November 15, 2024 | Volume: 67 | Issue: 12 | Pages: 4651-4662

10.1044/2024_jslhr-24-00283 | PMID 39546410

Purpose: Speakers with primary progressive apraxia of speech (PPAOS) have an insidious onset of motor speech planning/programming difficulties. As the disease progresses, the apraxia of speech (AOS) becomes more severe and a co-occurring dysarthria often emerges. Here, longitudinal data from speakers with phonetic- and prosodic-predominant PPAOS are used to characterize the progression of their motor speech impairment, including the development of dysarthria and mutism. Method: Data are presented from 52 speakers who had PPAOS at enrollment (i.e., progressive AOS in the absence of aphasia, cognitive, or other neurologic symptoms). Twenty-one had predominantly phonetic features, whereas 31 had primarily prosodic features. All participants underwent a comprehensive motor speech evaluation at their enrollment visit and each annual return visit, with a median of three visits per participant. Results: Almost 25% of the speakers with PPAOS presented with dysarthria at their enrollment visit (median disease duration of 3.65 years), whereas more than 70% of them had developed dysarthria by their last visit (median disease duration of 6.85 years). Neither the likelihood to develop dysarthria nor the disease duration at which it was detected differed significantly between the phonetic and prosodic groups. However, muteness emerged sooner for speakers with phonetic-predominant PPAOS; the median disease duration at which they became mute was 1.5 years shorter than for their prosodic counterparts. Conclusions: Clinically, these results facilitate more accurate prognostication of motor speech symptoms in speakers with PPAOS, allowing for timely introduction of alternative means of communication. The results also support the differentiation between progressive AOS and dysarthria as distinct motor speech disorders that often co-occur in these individuals.
Progressive Apraxia of Speech as a Manifestation of Spinocerebellar Ataxia 2

Neurology Genetics | November 1, 2024 | Volume: 10 | Issue: 6 | Pages: No page available

10.1212/nxg.0000000000200202 | PMID 39512795

Primary Progressive Aphasia Lacking Core Features of Nonfluent and Semantic Variants

Neurology | October 8, 2024 | Volume: 103 | Issue: 9 | Pages: No page available

10.1212/wnl.0000000000209924 | PMID 39656512

Automatic Speech Recognition in Primary Progressive Apraxia of Speech

Journal of Speech, Language, and Hearing Research | August 6, 2024 | Volume: 67 | Issue: 9 | Pages: 2964-2976

10.1044/2024_jslhr-24-00049 | PMID 39265154

Introduction: Transcribing disordered speech can be useful when diagnosing motor speech disorders such as primary progressive apraxia of speech (PPAOS), who have sound additions, deletions, and substitutions, or distortions and/or slow, segmented speech. Since transcribing speech can be a laborious process and requires an experienced listener, using automatic speech recognition (ASR) systems for diagnosis and treatment monitoring is appealing. This study evaluated the efficacy of a readily available ASR system (wav2vec 2.0) in transcribing speech of PPAOS patients to determine if the word error rate (WER) output by the ASR can differentiate between healthy speech and PPAOS and/or among its subtypes, whether WER correlates with AOS severity, and how the ASR's errors compare to those noted in manual transcriptions. Method: Forty-five patients with PPAOS and 22 healthy controls were recorded repeating 13 words, 3 times each, which were transcribed manually and using wav2vec 2.0. The WER and phonetic and prosodic speech errors were compared between groups, and ASR results were compared against manual transcriptions. Results: Mean overall WER was 0.88 for patients and 0.33 for controls. WER significantly correlated with AOS severity and accurately distinguished between patients and controls but not between AOS subtypes. The phonetic and prosodic errors from the ASR transcriptions were also unable to distinguish between subtypes, whereas errors calculated from human transcriptions were. There was poor agreement in the number of phonetic and prosodic errors between the ASR and human transcriptions. Conclusions: This study demonstrates that ASR can be useful in differentiating healthy from disordered speech and evaluating PPAOS severity but does not distinguish PPAOS subtypes. ASR transcriptions showed weak agreement with human transcriptions; thus, ASR may be a useful tool for the transcription of speech in PPAOS, but the research questions posed must be carefully considered within the context of its limitations. Supplemental Material: https://doi.org/10.23641/asha.26359417
Clinicopathologic and Neuroimaging Correlations of Nonverbal Oral Apraxia in Patients With Neurodegenerative Disease

Neurology | July 30, 2024 | Volume: 103 | Issue: 4 | Pages: No page available

10.1212/wnl.0000000000209717 | PMID 39079070

Incidence of Primary Progressive Apraxia of Speech and Primary Progressive Aphasia in Olmsted County, MN, 2011–2022

Neurology | July 30, 2024 | Volume: 103 | Issue: 4 | Pages: No page available

10.1212/wnl.0000000000209693 | PMID 39079073

Identifying and Addressing Functional Communication Challenges in Patients With Behavioral Variant Frontotemporal Dementia

American Journal of Speech-Language Pathology | June 6, 2024 | Volume: 33 | Issue: 4 | Pages: 1573-1589

10.1044/2024_ajslp-24-00013 | PMID 38843453

Purpose: We describe the communication challenges of four patients with a neurodegenerative disorder consistent with behavioral variant frontotemporal dementia (bvFTD), characterized by early behavioral and personality changes. By describing their clinical profiles, we identify common barriers to functional communication in this population and provide recommendations for how speech-language pathologists (SLPs) might contribute to minimizing them. Method: Four patients with bvFTD were selected from a cohort of patients with progressive communication impairments. Three of them returned for at least one follow-up visit. Case histories are presented along with the results of comprehensive speech and language, neuropsychological, and neurological testing. Results: At the time of initial evaluation, patients were between the ages of 54 and 66 years and had been experiencing symptoms for 1.5–6 years. Consistent with their bvFTD diagnoses, all patients had prominent behavioral and personality changes that impacted communication. Patients 1 and 2 also had mild aphasia at enrollment, primarily characterized by anomia and loss of word meaning. Patients 3 and 4 both had apraxia of speech and moderate-to-severe aphasia at enrollment with prominent anomia and agrammatism. All four patients had impaired executive functioning and relative sparing of visuospatial skills; episodic memory was also impaired for Patients 2 and 4. Even though functional communication was progressively limited for all patients, none of them received regular support from an SLP. Conclusions: This case series adds to a scant, but growing, literature demonstrating that patients with bvFTD have communication impairments. SLPs are uniquely positioned to identify barriers to functional communication and to provide tailored strategy training to the patients and their care partners over the course of their disease. Systematic evaluation of the efficacy of treatment in this population would be valuable. Supplemental Material: https://doi.org/10.23641/asha.25933762
Rehabilitation Treatment Specification System: Content and Criterion Validity Across Evidence-Based Voice Therapies for Muscle Tension Dysphonia

American Journal of Speech-Language Pathology | April 10, 2024 | Volume: 33 | Issue: 4 | Pages: 1774-1791

10.1044/2024_ajslp-23-00362 | PMID 38597797

Purpose: Systematically improving voice therapy outcomes is challenging as the clinician actions (i.e., active ingredients) responsible for improved patient functioning (i.e., targets) are relatively unknown. The theory-driven Rehabilitation Treatment Specification System (RTSS) and standard, voice-specific terminology based on the RTSS (RTSS-Voice) may help address this problem. This qualitative study evaluated if the RTSS and RTSS-Voice can describe four evidence-based voice therapies for muscle tension dysphonia without missing critical aspects (content validity) and identify commonalities and differences across them (criterion validity). Method: Qualitative interviews were completed between the clinicians (protocol experts) who developed and/or popularized the vocal function exercises, laryngeal reposturing, circumlaryngeal massage, and conversation training therapies as well as RTSS experts to produce RTSS specifications that met two consensus criteria: (a) The protocol expert agreed that the specification represented their treatment theory, and (b) the RTSS experts agreed that the specifications correctly adhered to both the RTSS framework and the RTSS-Voice's standard terminology. Results: The RTSS and RTSS-Voice comprehensively described voice therapy variations across and within the four diverse treatment programs, needing only the addition of one new target: overall auditory-perceptual severity. Conclusions: The RTSS and RTSS-Voice exhibited strong content validity. The standard RTSS-Voice terminology helped identify, for the first time, commonalities and differences in treatment ingredients, targets, and mechanisms of action across four treatments developed for the same patient population. In the long term, the RTSS and RTSS-Voice could provide the framework for an ever-growing collection of clinically meaningful and evidence-based therapy algorithms with potential to improve research, education, and clinical care. Supplemental Material: https://doi.org/10.23641/asha.25537624