Learning to preserve: foreign language training as a cognitive ‘vaccine’ to prevent old-age disorders?

Bilinguals constantly need to mentally juggle multiple languages. This is thought to increase cognitive flexibility, a skill needed to separate numerous languages in one mind but also to, among other things, adaptively respond to environmental demands. Learning a new language impacts first language processing and storage. It is for this unique interfering effect that foreign language training is expected to boost cognitive flexibility more than other cognitive training programs. Although there is a wealth of observational studies into bilingual advantages, experimental studies remain scarce. The primary objective of this study is to determine whether a bilingual experience affects cognitive flexibility and its neural underpinnings in elderly with subjective, but not objective, cognitive decline. We assess the unique role of foreign language training (n=66) compared to a music training (n=66) and social intervention (n=66). For three to six months, participants practise the language or musical skills at home five days a week for 45 minutes, and attend real-life classes every fortnight. Participants in the social intervention group will only meet every fortnight for some creative activities. Cognitive flexibility is assessed using, amongst others, a colour-shape switching task while measuring brain activity using combined fNIRS/EEG methods. We expect an increase in cognitive flexibility and positive effects on health (i.e. vulnerability for depression, subjective cognitive decline and quality of life) as a result of both language and music training, but more for the language training. In addition, we expect increased power in the theta band network and less hypo-activity in the lateral and medial PFC during switching measured through EEG and fNIRS, respectively. If effective, foreign language learning could serve as an important tool towards healthy aging: it could slow down cognitive aging and reduce vulnerability for depression.

Amendments 12-jan-2019:
- Additional questions are asked about family history of dementia.
- The ‘auditory elevator task (ANT subtest) will not be performed.
- The International English Language Testing System (IELTS) is used to measure English language proficiency in the language group after the training.

Addendum May 2021:
Due to the changing measures surrounding the corona crisis, it will not always be possible to receive research participants in the lab. Because we work with elderly people, who, according to the RIVM, fall into a risk category for the COVID-19 virus, receiving participants in the lab at the UMCG will be even more risky and often impossible. If the measures do not permit a visit to the lab, the research is conducted online where possible.

Amendments 1-7-2021:
- 113 participants instead of 198

This means that measurements that would take place in the lab are done online. Questionnaires will be completed online, interventions will be offered online and interviews will be conducted via an online video connection. Classes for the intervention are also online via video connection.

the foreign language training boosts cognitive flexibility and affects its neural underpinnings, which adds to cognitive reserve. The increase in cognitive flexibility is hypothesized to influence the experience of subjective cognitive decline. Besides that, the boost in cognitive flexibility is hypothesized to positively influence emotion regulation and thereby reduce depressive symptomatology.

T0: baseline (0 months): Geriatric Depression Scale (GDS), emotion regulation questionnaire (ERQ), Leuven Adaptation of Rumination on Sadness Scale (LARSS), Apathy Evaluation Scale (AES), Cognitive Failures Questionnaire (CFQ), Montreal Cognitive Assessment (MoCA), Cognitive Reserve Index questionnaire (CRIq), Ten Item personality Questionnaire (TIPI), World Health Organisation Quality of Life – abbreviated (WHOQOL-bref), loneliness scale, Trail Making Test (TMT), Digit Symbol Substitution Test (DSST), Digit span, verbal fluency tasks in L1 and L2, Peabody Picture Vocabulary Test (PPVT), colour-shape switching task, modified Wisconsin Card Sorting Task (mWCST), fNIRS/EEG measures.

T1: post-intervention (3 months): Geriatric Depression Scale (GDS), emotion regulation questionnaire (ERQ), Leuven Adaptation of Rumination on Sadness Scale (LARSS), Apathy Evaluation Scale (AES), Cognitive Failures Questionnaire (CFQ), Montreal Cognitive Assessment (MoCA), Ten Item personality Questionnaire (TIPI), World Health Organisation Quality of Life – abbreviated (WHOQOL-bref), loneliness scale, Trail Making Test (TMT), Digit Symbol Substitution Test (DSST), Digit span, verbal fluency tasks in L1 and L2, Peabody Picture Vocabulary Test (PPVT), colour-shape switching task, modified Wisconsin Card Sorting Task (mWCST), fNIRS/EEG measures.

T2: Geriatric Depression Scale (GDS), emotion regulation questionnaire (ERQ), Leuven Adaptation of Rumination on Sadness Scale (LARSS), Apathy Evaluation Scale (AES), Cognitive Failures Questionnaire (CFQ), Montreal Cognitive Assessment (MoCA), Ten Item personality Questionnaire (TIPI), World Health Organisation Quality of Life – abbreviated (WHOQOL-bref), loneliness scale, Trail Making Test (TMT), Digit Symbol Substitution Test (DSST), Digit span, verbal fluency tasks in L1 and L2, Peabody Picture Vocabulary Test (PPVT), colour-shape switching task, modified Wisconsin Card Sorting Task (mWCST), fNIRS/EEG measures.

T3: follow-up (12 months): Geriatric Depression Scale (GDS), emotion regulation questionnaire (ERQ), Leuven Adaptation of Rumination on Sadness Scale (LARSS), Apathy Evaluation Scale (AES), Cognitive Failures Questionnaire (CFQ), Montreal Cognitive Assessment (MoCA), Cognitive Reserve Index questionnaire (CRIq), World Health Organisation Quality of Life – abbreviated (WHOQOL-bref), loneliness scale, Trail Making Test (TMT), Digit Symbol Substitution Test (DSST), Digit span, verbal fluency tasks in L1 and L2, Peabody Picture Vocabulary Test (PPVT), colour-shape switching task, modified Wisconsin Card Sorting Task (mWCST).

foreign language training