Silent Pauses and Speech Indices as Biomarkers for Primary Progressive Aphasia
Constantin Potagas,
Zoi Nikitopoulou,
Georgia Angelopoulou,
Dimitrios Kasselimis,
Nikolaos Laskaris,
Evie Kourtidou,
Vasilios C. Constantinides,
Anastasia Bougea,
George P. Paraskevas,
Georgios Papageorgiou,
Dimitrios Tsolakopoulos,
Sokratis G. Papageorgiou,
Elisabeth Kapaki
Affiliations
Constantin Potagas
Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Zoi Nikitopoulou
Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Georgia Angelopoulou
Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Dimitrios Kasselimis
Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Nikolaos Laskaris
Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Evie Kourtidou
Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Vasilios C. Constantinides
1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Anastasia Bougea
1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
George P. Paraskevas
1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Georgios Papageorgiou
Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Dimitrios Tsolakopoulos
Neuropsychology and Language Disorders Unit, 1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Sokratis G. Papageorgiou
1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Elisabeth Kapaki
1st Department of Neurology, Eginitio Hospital, National and Kapodistrian University of Athens, 115 28 Athens, Greece
Background and Objectives: Recent studies highlight the importance of investigating biomarkers for diagnosing and classifying patients with primary progressive aphasia (PPA). Even though there is ongoing research on pathophysiological indices in this field, the use of behavioral variables, and especially speech-derived factors, has drawn little attention in the relevant literature. The present study aims to investigate the possible utility of speech-derived indices, particularly silent pauses, as biomarkers for primary progressive aphasia (PPA). Materials and Methods: We recruited 22 PPA patients and 17 healthy controls, from whom we obtained speech samples based on two elicitation tasks, i.e., cookie theft picture description (CTP) and the patients’ personal narration of the disease onset and course. Results: Four main indices were derived from these speech samples: speech rate, articulation rate, pause frequency, and pause duration. In order to investigate whether these indices could be used to discriminate between the four groups of participants (healthy individuals and the three patient subgroups corresponding to the three variants of PPA), we conducted three sets of analyses: a series of ANOVAs, two principal component analyses (PCAs), and two hierarchical cluster analyses (HCAs). The ANOVAs revealed significant differences between the four subgroups for all four variables, with the CTP results being more robust. The subsequent PCAs and HCAs were in accordance with the initial statistical comparisons, revealing that the speech-derived indices for CTP provided a clearer classification and were especially useful for distinguishing the non-fluent variant from healthy participants as well as from the two other PPA taxonomic categories. Conclusions: In sum, we argue that speech-derived indices, and especially silent pauses, could be used as complementary biomarkers to efficiently discriminate between PPA and healthy speakers, as well as between the three variants of the disease.
