

In addition to the standard linguistic features used in previous studies on connected speech data during neuropsychological tests, we extracted novel features related to atypical repetition of words and topics reported by previous observational and descriptive studies as one of the prominent characteristics in everyday conversations of AD patients.

Methods: We analyzed daily conversational data of seniors with and without AD obtained from longitudinal follow-up in a regular monitoring service (from n=15 individuals including 2 AD patients at an average follow-up period of 16.1 months 1032 conversational data items obtained during phone calls and approximately 221 person-hours). Objective: The objective of this study was to explore the linguistic features that can be used for differentiating AD patients from daily conversations. However, whether and how we can quantify language dysfunction in daily conversation remains unexplored.

Previous studies have succeeded in quantifying language dysfunctions and identifying AD from speech data collected during neuropsychological tests.
