Background and Objectives
Bilingualism has been suggested to protect older adults from cognitive aging and delay the onset of dementia. However, no studies have systematically explored bilingual usage as a tool to mitigate age-related cognitive decline. We developed the Dual-Language Intervention in Semantic memory – Computerized (DISC), a novel cognitive training program with three training tasks (object categorization, verbal fluency, and utility of things) designed specifically for older adults that featured two modes: single-language (SL) exposure mode and dual-language (DL) exposure mode.
Research Design and Methods
The final sample included 50 cognitively healthy (CH; 33 female, Mage=72.93 years, range=53.08 – 87.43 years) and 48 cognitively impaired (CI; 35 female, Mage=80.93 years, range=62.31 – 96.67 years) older adults, randomly assigned them into one of three groups: SL group, DL group, and control group (no training). Participants in SL and DL groups used DISC in either SL mode (i.e., training instructions were spoken in only one language throughout the entire training) or DL mode (i.e., training instructions alternated between two languages) respectively over 24 sessions. Participants in the control group were asked to continue with their normal daily activities (e.g., playing bingo, reading newspapers).
Results
For CH older adults, we found significant improvements in the Rey Auditory Verbal Learning Test (RAVLT) Trial 5 score, and the Clock Drawing Test score, in the DL group but not in the SL and control groups post-training compared to pre-training. For CI older adults, there was a delayed improvement in the RAVLT Trial 1, 6 months later.
Discussion and Implications
Our findings provided novel evidence that implementing DL cognitive training benefits CH older adult’s late verbal learning and visuospatial construction skills, and a delayed improvement in CI older adults’ early verbal learning abilities.