Abstract
In this thesis I explore two strands of research: in the first half I explore the effects
of language learning on brain structure and cognitive function. In the second half
I study to what extent educational attainment alter the rate of cognitive decline
in old age. These different strands of research are united through the concept of
brain plasticity, which is the brain’s ability to change its structural configuration
in response to new experiences.
In Study I we charted the neural underpinning of foreign language learning in a
sample of younger adults. A total of 56 younger adults were randomized to either
a 10-week beginner’s course in Italian or a control condition. For those studying
Italian we found that grey-matter change in the right hippocampus was associated
with how much time they spent practicing, rather than with how good they
became suggesting that effort, rather than achieved proficiency, is what drives
neuroplastic change.
Study II presents the largest (to date) randomized trial looking into the causal effects
of language learning as cognitive engagement in older age, specifically foreign
language learning. 160 people between ages 65 and 75 were randomized to either
an 11-week beginner’s course in Italian, or an 11-week relaxation training course.
While we predicted that language learning would improve cognitive function,
specifically associative memory, we found no evidence to support this hypothesis.
Study III and IV address the question of whether or not educational attainment
affects the rate of cognitive decline in old age. While it is clear that educational
attainment is associated with level of cognitive function, we find no evidence
that it alters the rate of decline in old age. Study III address this question using a
novel statistical approach while Study IV presents a meta-analysis on the subject,
arriving at similar conclusions.
