Neural mechanisms and brain structures underlying individual differences in acquisition of vocabulary and grammar of an artificial language. A neurolinguistic study of language aptitude.

There are large differences in the way individual human brains work and are
built and although there is some debate as to whether parameters such as the
size of different brain structures, the number of neurons used to perform
certain functions and the integrity of white matter influence information
processing, recent studies show that some of these inter-individual differences
correlate with specific cognitive tasks, such as language learning. People
differ substantially in their ability to learn languages, especially when it
comes to second language acquisition and this universally observable fact may
be linked with the diversity of human brains. Thus, the main question posed in
this study is whether language aptitude, as measured by standardized test
instruments, corresponds to particular localization patterns of brain activity
during learning and to inter-individual differences in the white matter
structure.

Primary Objective: The main objective is to gain insight into the functional
and structural neural correlates of success in foreign language learning. To
this end, fMRI and DTI data will be acquired together with behavioral responses
from healthy adults while conducting (1) a grammar acquisition task and (2) a
vocabulary acquisition task.
Secondary Objective(s): The secondary objective of this study is to examine the
neural network mediating the acquisition of novel grammatical rules and
vocabulary. To this end, imaging data gathered in two tasks will be analyzed
and the time course of activity changes during both tasks compared with each
other.

The participants will perform a grammar acquisition task or a vocabulary
acquisition task while fMRI data and manual responses are acquired. Memory
performance will be assessed on a separate occasion, after the scanning. The
experiment will be carried out using a 3T fMRI scanner at the LUMC. Before
experimental session starts, subjects will take part in a behavioral training
session outside the scanner to become familiar with the task.
Half of the participants will perform the grammar acquisition task, another
half the vocabulary acquisition task. The participants will be placed
comfortably in the scanner, total scanning time is approximately one hour.
Participants will spend a total of approximately 1,5 hours in the lab,
performing behavioral practice testing and filling out questionnaires in
addition to performing tasks in the scanner.

Participating in an fMRI and DTI study has not been associated to any known
risks. This non-invasive techniques involve no catheterizations or introduction
of exogenous tracers. Numerous children and adults have undergone magnetic
resonance studies without apparent harmful consequences. Some people become
claustrophobic while inside the magnet and in these cases the study will be
terminated immediately at the subject's request. The only absolute
contraindications to MRI studies are the presence of intracranial or
intraocular metal, or a pacemaker. Relative contraindications include pregnancy
and claustrophobia. Participants who may be pregnant, who may have metallic
foreign bodies in the eyes or head, or who have cardiac pacemakers will be
excluded because of potential contraindications of MRI in such subjects.
Although there is no direct benefit to the participants from this proposed
research, there are greater benefits to society from the potential knowledge
gained from this study. Insights in the neural basis of success in foreign
language learning has implications for understanding the neural organization of
the language system which in turn might help in developing strategies for
relearning a language in patients with aphasia.