Older people with mild cognitive impairment exhibit lower semantic noise after six months of frequent social conversations

Abstract

AbstractBackgroundSemantic noise (SN) is a linguistic measurement that quantifies how well the conversation focuses on topics they are discussing. We hypothesized that by engaging in high frequent conversation which aimed to enhance cognitive reserve, the SN observed in older people’s conversations with mild cognitive impairment (MCI) would resemble those with normal cognition (NC).MethodWe analyzed transcriptions from a behavioral intervention randomized controlled trial, I‐CONECT (NCT02871921), which involved semi‐structured conversations between facilitators and participants. In the project, the experimental group engaged in 30‐minute semi‐structured conversations (four times per week for 6 months) via video‐chats. Every video‐chat is oriented to a predefined topic which was provided in a standardized order (e.g., dancing is the 1st conversation topic in the 2nd week). Out of 186 subjects randomized into the trial, 64 participants were randomized into the experimental group. Among them, 52 participants (26 MCI and 26 normal based on NACC D1) with sufficient recording quality during the 2nd week of the intervention (baseline) and during the last week (i.e., 24th) before the month 6 (M6) post‐intervention assessments (post‐trial assessments at M6) were used in this analysis. We utilized an automatic speech recognition (ASR) system to transcribe these recordings and measured each transcription’s SN. We analyzed the statistical difference of MSN (mean SN) between participants with MCI and those with NC at baseline (2nd week) and M6 (24th week).ResultsUsing two‐tailed t‐test, we found that at the baseline, MSN in MCI group was significantly higher than NC group (MCI: 2.09(0.34), NC: 1.87(0.35), p‐value: 0.024). After six months of social interaction, MCI and NC group were not significantly different (MCI: 1.81(0.47), NC: 1.95(0.47), p‐value: 0.280). Moreover, in MCI group, baseline’s MSN was significantly higher than M6’ (p‐value: 0.017), while, in NC group, there was no significant difference between baseline and M6 (p‐value: 0.465).ConclusionsWe showed that, through six months of social interaction, MCI group’s MSN reduces from significantly higher than NC group at the baseline to not significantly different from NC group at M6. This indicates that the high dosage of interactive conversations reduces MSN in the MCI group.