Lexical and acoustic speech features relating to Alzheimer’s disease pathology

INTRODUCTION In this study, we compared digital speech features of AD and lvPPA patients in a biologically confirmed cohort and related them to specific neuropsychiatric test scores and CSF proteins. METHODS We extracted language variables with automated lexical and acoustic pipelines from oral picture descriptions of 44 AD and 21 lvPPA patients with autopsy or CSF confirmation of AD pathology. We correlated distinct speech features with MMSE and BNT test scores and CSF p-tau levels. RESULTS LvPPA patients produced fewer verbs, adjectives, and more fillers with lower lexical diversity and higher pause rate than AD. Both groups showed some shared language impairments compared with normal speakers. DISCUSSION Our speech measures captured differences in speech between the two phenotypes. Also, shared speech markers were linked to the common underlying pathology. This work demonstrates the potential of natural speech analysis in detecting underlying AD pathology. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study was funded by grants from the National Institute of Health (AG066597, AG054519, NS109260, P30 AG072979), Alzheimer's Association (AACSF-18-567131, AARF-D-619473, AARF-D-619473-RAPID), Department of Defense (PR192041). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The Institutional Review Board of the Hospital of the University of Pennsylvania approved the study of human subjects, and all participants agreed to participate in the study by written consent. All digital data was stored in secured HIPAA-compliant servers and handled by personnel trained in PPI protection. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes Data will be available upon request from appropriate research groups.